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    A Study on the Quality Stability of Wheat Grains at Designated Locations Across Multiple Years
    ZHAO BoHui, ZHANG YingQuan, JING DongLin, LIU BaoHua, CHENG YuanYuan, SU YuHuan, TANG Na, ZHANG Bo, GUO BoLi, WEI YiMin
    Scientia Agricultura Sinica    2024, 57 (9): 1833-1844.   DOI: 10.3864/j.issn.0578-1752.2024.09.016
    Abstract71)   HTML12)    PDF (2211KB)(46)       Save

    【Objective】The stable quality of wheat raw grain can keep the processing technology and its parameters basically unchanged, reduce human intervention in the processing process and the loss of process adjustment, and ensure the stability of the quality of flour products. The evaluation of variety quality stability could provide the reference for processing enterprises to purchase stable quality raw grain.【Method】In this experiment, seven wheat varieties, including Shiluan 02-1, Jimai 22, Liangxing 99, Han 6172, Yingbo 700, Luyuan 502, and Gaoyou 2018, were planted in Xingtai and Handan cities from 2013 to 2019 and selected as trial samples. The coefficient of variation was used to quantitatively characterize the quality stability of varieties over multiple years and locations. The product of test weight, crude protein in grains, wet gluten content, and dough stability time was calculated, and its coefficient of variation was used as a comprehensive statistical measure of quality stability. Pairwise analysis of varieties in the same year and location was conducted to analyze the stability of their quality indicators.【Result】The fluctuation ranges of test weight, crude protein in grains, wet gluten content, dough stability time, and the coefficient of variation of the product of quality indicators were 0.06%-5.50%, 0.01%-12.21%, 0.03%-10.02%, 0.4%-138.69%, and 0.32%-140.01%, respectively. Pairwise analysis showed that the stability of test weight from high to low was Gaoyou 2018, Luyuan 502, Han 6172, Liangxing 99, Yingbo 700, Jimai 22, and Shiluan 02-1. The stability of crude protein in grains from high to low was Gaoyou2018, Han 6172, Yingbo 700, Luyuan 502, Liangxing 99, Jimai 22, and Shiluan 02-1. The stability of wet gluten content from high to low was Gaoyou 2018, Han 6172, Luyuan 502, Yingbo 700, Liangxing 99, Shiluan 02-1, and Jimai 22. The stability of dough stability time from high to low was Yingbo 700, Jimai 22, Gaoyou 2018, Luyuan 502, Han 6172, Liangxing 99, and Shiluan 02-1. The stability of the product of the above quality indicators from high to low was Yingbo 700, Gaoyou 2018, Luyuan 502, Liangxing 99, Han 6172, Jimai 22, and Shiluan 02-1. 【Conclusion】Among the tested quality indicators, test weight showed higher stability, while dough stability time exhibited lower stability. The stability of crude protein in grains and wet gluten content fell between the two. By using the coefficient of variation of the product of four quality indicators as the evaluation criterion, Yingbo 700 demonstrated higher quality stability among the trial varieties.

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    Characteristics of Good Taste and High Yield Type Japonica Rice in the Lower Reaches of the Yangtze River
    ZHU TianCi, MA TianFeng, KE Jian, ZHU TieZhong, HE HaiBing, YOU CuiCui, WU ChenYang, WANG GuanJun, WU LiQuan
    Scientia Agricultura Sinica    2024, 57 (4): 820-830.   DOI: 10.3864/j.issn.0578-1752.2024.04.015
    Abstract101)   HTML12)    PDF (1590KB)(50)       Save

    【Objective】In order to explore the common agronomic and physiological characteristics of good taste and high yield type japonica rice in the lower reaches of the Yangtze River, the study could provide theoretical basis and technical support for realizing synergistic improvement of rice yield and quality in this region. 【Method】The cultivar screening tests were conducted in 2018 and 2022 using 14 and 13 conventional japonica rice cultivars, respectively, to systematically compare the yield and composition, taste quality and textural characteristics, as well as agronomic and physiological indicators such as biomass, stem non-structural carbohydrates (NSC), and leaf area duration (LAD) among the different cultivars.【Result】The taste value and yield varied across the different cultivars, so through clustering by taste value and yield, they can be further divided into three types: medium taste and low yield (ML), medium taste and high yield (MH), good taste and high yield (GH). The average taste value and yield of GH in two years were 68.5 and 10.2 t·hm-2, respectively, which were 6.8% higher in taste value and 14.6% higher in yield than MH and ML. In terms of performance for yield and quality traits, GH showed the highest grain filling percentage and taste scores compared to MH and ML. In terms of the dry matter accumulation, GH increased the proportion of dry matter accumulation at the early stage of grain filling stage, and showed the highest dry matter accumulation from heading stage to 15 days after heading stage. Further analysis of the causes of dry matter accumulation at this stage revealed that GH significantly increased the NSC remobilization rate while steadily increasing LAD. Correlation analyses showed highly significant positive correlations between grain filling percentage and taste, dry matter accumulation and LAD from heading stage to 15 days after heading stage, and NSC remobilization rate.【Conclusion】 While maintaining a high LAD from heading stage to 15 days after heading stage (100.4 m2·m-2·d), further increasing NSC remobilization rate during grain filling stage (79.9%) to promote the initiation of grain filling, increasing the dry matter accumulation from heading stage to 15 days after heading stage (3.6 t·hm-2), then improving the grain filling percentage (95.4%), and taste (9.6), which are the common characteristics of good taste and high yield type japonica rice in this region. In addition, the development of water and fertilizer management techniques targeting the enhancement of NSC remobilization at the grain filling stage and NSC accumulation at heading stage is expected to further exploit the yield and taste quality potential of the above good taste and high yield type japonica rice.

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    Comparison of Heat Tolerance of Maize Hybrids and Their Parental Inbreds with Different Genotypes
    XU TianJun, LÜ TianFang, LI ZiHao, ZHANG Yong, LIU HongWei, LIU YueE, CAI WanTao, ZHANG RuYang, SONG Wei, XING JinFeng, ZHAO JiuRan, WANG RongHuan
    Scientia Agricultura Sinica    2024, 57 (2): 403-415.   DOI: 10.3864/j.issn.0578-1752.2024.02.014
    Abstract129)   HTML12)    PDF (4552KB)(107)       Save

    【Objective】 In recent years, the adverse weather of high temperature and heat damage in the Huang-Huai-Hai maize region of China occurred frequently, which has become an important adverse factor threatening maize production. Study and clarify the effects of high temperature stress on male and female ear characteristics and yield of maize can provide useful guidance for the cultivation and selection of high temperature tolerant maize varieties. 【Method】 The variety of Zhengdan958 (Zheng58×Chang7-2), Xianyu335 (PH6WC×PH4CV), Jingnongke728 (JingMC01×Jing2416), MC812 (JingB547×Jing2416), and their parents were used as the test materials. High temperature stress before and after flowering (from V12 stage to 7 d after silking) were conducted. The effects of high temperature stress on the growth and development of male and female panicles, ASI, pollen activity, yield and yield components of different genotypes of maize hybrids and their parents were studied. 【Result】 High temperature stress before and after anthesis significantly reduced the ear length, rows per ear and grains per row of the tested maize varieties and their parents, and then resulted significant decrease in yield. Compared with the control, the grain number per spike of Zhengdan958, Xianyu335, Jingnongke728 and MC812 decreased by 22.28%, 47.69%, 6.13% and 8.11% respectively under high temperature stress, resulting yield decrease of 9.50%, 50.61%, 3.17% and 5.00% respectively. Among the parental materials, the decrease of rows per panicle, grains per row and yield of Jing2416 under high temperature treatment was the smallest and not significant, while the decrease of PH6WC was the largest. Under high temperature stress, the total number of tassel branches, the length of tassel, the total amount of loose pollen and pollen activity decreased significantly, the silking period of loose pollen was prolonged, and the duration of loose pollen was shortened. Among them, Jingnongke728 had the smallest decline, followed by MC812, showing good heat resistance, while Zhengdan958 had the largest decline in the length of tassel, but the amount of pollen was the largest due to the large number of tassel branches. Xianyu335 has fewer male panicle branches, a large decrease in male panicle length, the least amount of pollen and low activity. Among the parental materials, Jing2416 had a large amount of total loose pollen and strong pollen vitality under high temperature treatment, with the smallest decline, only 4.50 and 3.98 percentage points. Compared with the control, the interval of loose pollen silking (ASI) was prolonged by 1.6d under high temperature stress. The decrease in male spike length is manifested as Zhengdan958>Xianyu335>MC812>Jingnongke728. Zhengdan958 had the largest decrease in male spike length, but had more branches and the largest pollen yield; Xianyu335 has fewer branches of male spikes, a significant decrease in male spike length, the least pollen quantity, and the lowest activity; Jing 2416 has a large amount of loose pollen and strong pollen vitality, with the smallest decrease (only 4.50% and 3.98%). 【Conclusion】 High temperature stress before and after anthesis has a significant impact on the grain yield, male and female ear development process, pollen activity and filament microstructure of the tested maize varieties. Under high temperature stress at this stage, the decline of yield and pollen activity of Jingnongke728 and MC812 is significantly less than Xianyu335, showing higher single ear yield and heat tolerance. By comparing the heat resistance of the parental inbred lines of the tested maize hybrids, it was found that the heat resistance of the paternal inbred lines was better than that of the maternal inbred lines. The male panicle branch and length of the parent material Jing2416 decreased slightly, the amount of pollen was large, the pollen activity was high, the filaments were hairy, the ability to capture pollen was strong, the single panicle yield was high, and the heat resistance was the best. Therefore, in the planting area with frequent high temperature and heat damage, selecting maize varieties such as Jingnongke728 can achieve stable and high yield; and during the maize breeding process, we should pay more attention to the utilizing of the higher temperature resistant inbred such an Jing2416 and then combination higher temperature maize varieties.

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    Characteristics of Endophytic Microbial Community Structures in Stems Between Hylocereus undatus and H. polyrhizus
    ZHOU XinYan, CHEN SiYu, WEI YuFei, ZHU Yu, FENG JunQian, DING DianCao, LU GuiFeng, YANG ShangDong
    Scientia Agricultura Sinica    2024, 57 (2): 416-428.   DOI: 10.3864/j.issn.0578-1752.2024.02.015
    Abstract95)   HTML6)    PDF (4336KB)(107)       Save

    【Objective】 The differences of the endophytic microbial community structures between Hylocereus undatus and H. polyrhizus were analyzed, so as so to explore the correlation between the pulp color of H. polyrhizus and the endophytic microbial community composition and their functional microorganisms. 【Method】 Based on high-throughput sequencing technology, the diversity and richness of endophytic microorganisms (bacteria and fungi) in stems between H. undatus and H. polyrhizus were analyzed. Meanwhile, based on LEfSe analysis, the differences of endophytic microorganisms in stems between H. undatus and H. polyrhizus were also investigated.【Result】 The significant differences of the endophytic microbial community structures were found in stems between H. undatus and H. polyrhizus. Meanwhile, the numbers of specific bacterial and fungal OTUs in stems of H. polyrhizus were all higher than those of H. undatus. At the phylum level, the relative abundance ratio of Ascomycota in stems of H. polyrhizus was 1.15 times higher than that of H. undatus. At the genus level, Streptomyces and Penicillium were the highest abundant dominant bacterial and fungal genera in stems of H. polyrhizus, which were 1.24 and 4.27 times higher than those of H. undatus, respectively. In addition, some bacterial genera, such as Lechevalieria, Glycomyces, unclassified_f__Enterobacteriaceae, Actinomadura, and some fungal gerera, such as Talaromyces, unclassified_f__Serendipitaceae, unclassified_c__GS13, unclassified_o__Atractiellales, unclassified_o__Auriculariales were enriched in stems of H. polyrhizus. LEfSe analysis also showed that Promicromonospora and Xylomyces were significant enriched in stems of H. polyrhizus. 【Conclusion】 All above results suggested that the formation of pigment was closely related to the compositions of endophytic microbial community in stems of H. polyrhizus. The bacterial genera, such as Streptomyces, unclassified_f__Enterobacteriaceae, Promicromonospora, and the fungal phylum and genera, such as Ascomycota, Penicillium, Talaromyces and Xylomyces, were all the potential microorganisms in relating to pigment synthesis and metabolic accumulation in stems of H. polyrhizus.

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    Changes of Endogenous Hormones and Polyamines During Ovule Development of Stenospermocarpic Seedless Grape
    ZHU PeiPei, QIN HaoXiang, ZHANG JianXia
    Scientia Agricultura Sinica    2023, 56 (23): 4789-4800.   DOI: 10.3864/j.issn.0578-1752.2023.23.018
    Abstract105)   HTML9)    PDF (536KB)(214)       Save

    【Objective】By exploring the effects of endogenous hormones and polyamines on embryo development during the ovule development of seedless grape, this study provided a theoretical basis for promoting embryo development by spraying exogenous hormones before anthesis and adding exogenous hormones into the medium in vitro culture of ovule.【Method】In this study, the European grape (Vitis vinifera L.) variety Jingxiu and its F1 generation stenospermocarpic seedless variety Qinxiu were used as test materials. The content of endogenous hormones and polyamines in ovule of fruit at different developmental stages were compared by high performance liquid chromatography mass spectrometry (HPLCMS) and ultra performance liquid chromatography (UPLC).【Result】The content of IAA, ZT, ZR, and iPAS reached their highest values at 39 DAF (days after flowering) for Jingxiu and 42 DAF for Qinxiu, and the highest values of the former were higher than those of the latter (more than 1.5 times). For the content of JA and SA, Jingxiu started to rise sharply at 36 DAF (2 000 ng∙g-1 and 6 500 ng∙g-1, respectively), and reached the highest values at 39 DAF (6 500 ng∙g-1 and 10 000 ng∙g-1, respectively), and then, which were declining and remaining at a high level at 42-45 DAF, while Qinxiu was declining and remaining at a low level from 36 DAF (3 500 ng∙g-1 and 3 000 ng∙g-1, respectively). The ACC content of Jingxiu was almost 0 ng∙g-1 at 39 DAF, then increased rapidly and reached its highest value (1 200 ng∙g-1) at 45 DAF, while Qinxiu reached its highest value (900 ng∙g-1) at 39 DAF, then declined to 0 ng∙g-1 at 42 DAF, and remained at a very low level. The ABA content of Jingxiu was almost 0 ng∙g-1 from 36 to 45 DAF, while that of Qinxiu rose sharply from 0 ng∙g-1 at 39 DAF to the highest value (900 ng∙g-1) at 42 DAF. The trends of Put (putrescine), Spm (spermine), and Spd (spermidine) were similar for the two varieties, but Jingxiu was consistently higher than Qinxiu. The highest values of Put and Spd were 42 DAF for Jingxiu and 39 DAF for Qinxiu, except for the highest values of Spm, which were all found at 42 DAF. 【Conclusion】 The lower content of growth promoting substances (IAA, CTK, GA3, ACC, JA, SA, Put, Spd, and Spm) and the higher content of growth inhibiting substances (ABA), and lower ratios of (IAA+GA3)/ABA, (IAA+ZT+GA3)/ABA, Spm/PAs, (Spd+Spm)/PAs, and (Spd+Spm)/Put in the ovules of the seedless variety Qinxiu compared with the seeded variety Jingxiu might be one of the main reasons for seedless grape embryo abortion. Therefore, in the process of seedless grape embryo rescue, the embryo abortion could be inhibited by spraying before flowering or adding to media a certain concentration of growth promoting substances.

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    The Modification of Gene Editing Vector for Efficient GFPuv Fluorescence Screening and Its Application in Potato Genetic Transformation
    DU JingYa, CHEN KaiYuan, PU Jin, ZHOU HuiYing, ZHU GuangTao, ZHANG ChunZhi, DU Hui
    Scientia Agricultura Sinica    2023, 56 (11): 2223-2236.   DOI: 10.3864/j.issn.0578-1752.2023.11.015
    Abstract257)   HTML27)    PDF (3831KB)(806)       Save

    【Objective】The improvement and innovation of screening markers contributes to the development of transgenic technology, among which the visual screening markers are widely modified for better effect. Recent studies revealed that an enhanced Yellow Green Fluorescent like Protein (eYGFPuv (GFPuv)) obtained by mutation can emit strong and stable green fluorescence under 365 nm UV light irradiation and be easily observed. Constructing the gene editing vector with GFPuv fluorescence screening marker and carrying out experiment application and verifications in potato genetic transformation will provide technical support for the screening of positive transgenic plants in potato transformation, and lay the foundation for using genome editing technology to create potato male sterile lines in the future. 【Method】By using homologous recombination, the GFPuv expression framework and gene editing element Cas9_sgRNA were successively recombined into pCAMBIA2300 vector, and then with this new designed vector the Agrobacterium-mediated transient expression assay was conducted in tobacco plants. Six editing vectors with potato anther development conservative genes were constructed using this modified vector. The A. rhizogenes strains Ar qual and MSU440 harbouring these vectors were transformed into the potato stem segments respectively, and then the A. rhizogenes-induced hairy roots with green fluorescence were observed and counted under the portable UV lamp. The transformation efficiency and editing efficiency of these vectors were analyzed using hairy root transformation system in two different potato genotypes. In the end, the modified vectors were applied to produce transformed potato plants with modifications on target genes. 【Result】A novel gene editing vector pCAMBIA2300MGFPuv-sgRNACas harbouring a GFPuv fluorescence marker was successfully constructed, and the transient transformation in tobacco plants confirmed that the GFPuv expression framework was expressed successfully. The hairy roots with green fluorescence were screened after the transformation with two kinds of A. rhizogenes, and an additional supplement of kanamycin (Kan) significantly increased the proportion of positive fluorescent roots. Although the transformation rates of the two strains were not significantly different, the hairy roots of MSU440 formed faster. Furthermore, the transformation rates and editing rates of editing vectors for six potato anther development conservative genes in two different potato genotypes were the same, but the editing rates of six target sites differed significantly. Potato genetic transformation using the modified vector confirmed that GFPuv fluorescence could be used for the screening of transgenic callus and plants in potato. 【Conclusion】The hairy root transformation system mediated by A. rhizogenes is an essential approach to verifying the efficiency of gene editing, and GFPuv fluorescence can be used in the screening of transgenic plants in potato transformation.

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    Curcumin Alleviates Zearalenone-Induced Oxidative Damage in Porcine Renal Epithelial Cells via SIRT1/FOXO1 Pathway
    CUI HongJie, LU ChunTing, PAN LiQin, HU Hui, ZHONG PeiYun, ZHU JieYing, ZHANG KaiZhao, HUANG XiaoHong
    Scientia Agricultura Sinica    2023, 56 (5): 1007-1018.   DOI: 10.3864/j.issn.0578-1752.2023.05.015
    Abstract269)   HTML29)    PDF (2402KB)(108)       Save

    【Objective】 The purpose of this study was to investigate the protective effect of curcumin (Cur) on zearalenone (ZEA)-induced oxidative damage in porcine renal epithelial cells (PK-15), and to elucidate the protective mechanism based on SIRT1/FOXO1 signaling pathway. 【Method】 The experiment was divided into 5 groups: control group, ZEA group (36.55 μg·mL-1 ZEA), Cur6.25 group (36.55 μg·mL-1 ZEA+6.25 μmol·L-1 Cur), Cur12.5 group (36.55 μg·mL-1 ZEA+12.5 μmol·L-1 Cur), and Cur25 group (36.55 μg·mL-1 ZEA +25 μmol·L-1 Cur). MTT assay was used to determine the half inhibitory concentration of ZEA and the maximum safe concentration of Cur on PK-15 cells. The morphological changes were observed by inverted microscope. The levels of intracellular reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) were detected by the reagent kits. Real-time quantitative PCR was used to detect the mRNA levels of SIRT1, FOXO1, CAT and Mn-SOD. The expression levels of SIRT1, FOXO1 and Acetyl-FOXO1 proteins were detected by Western Blot. 【Result】 The IC50 of ZEA was 36.55 μg·mL-1, and the maximum safe concentration of Cur was 25 μmol·L-1. Compared with the control group, ZEA significantly decreased the cell viability of PK-15 cells (P<0.01), significantly increased the levels of ROS and MDA (P<0.01), and significantly decreased the activities of SOD and CAT (P<0.01). Compared with ZEA group, the different concentrations of Cur (6.25, 12.5, 25 μmol·L-1) significantly increased the cell viability of PK-15 cells (P<0.05) and improved the cell morphology. ROS and MDA levels induced by ZEA were also significantly reduced by Cur (P<0.01). Moreover, SOD and CAT activities in cells were significantly increased (P<0.01). qRT-PCR results showed that, compared with the control group, ZEA decreased SIRT1 mRNA expression, significantly increased FOXO1 mRNA expression (P<0.01), increased Mn-SOD mRNA expression, and significantly decreased CAT mRNA expression (P<0.01). Compared with ZEA group, mRNA expression levels of SIRT1 and CAT were increased in different degrees, FOXO1 mRNA expression levels were significantly decreased (P<0.01), and Mn-SOD mRNA expression levels were significantly increased (P<0.01) in all Cur groups. Western Blot results showed that ZEA significantly reduced SIRT1 protein expression (P<0.05), and significantly increased Acetyl-FOXO1 protein expression (P<0.01). Compared with ZEA group, SIRT1 protein expression was significantly increased (P<0.01), while Acetyl-FOXO1 protein expression was significantly decreased (P<0.01) in all Cur groups.【Conclusion】 Cur could up-regulate the expression of SIRT1, reduce the acetylation level of FOXO1, and induce the expression of antioxidant enzymes Mn-SOD and CAT, thereby eliminating ROS, reducing the level of MDA, and alleviating the oxidative damage of ZEA on PK-15 cells.

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    Effects of Seed Soaking with Chitooligosaccharide on the Growth of Sprout and Endogenous Phytohormone Content in Potato Minitubers
    YE Nan, ZHU Yan, ZHAO YuanShou, ZHU JianNing, MEN JiaWei, CHEN Fu, KONG DeYuan, ZHANG WeiBing, ZONG YuanYuan, LI YongCai
    Scientia Agricultura Sinica    2023, 56 (4): 788-800.   DOI: 10.3864/j.issn.0578-1752.2023.04.016
    Abstract276)   HTML34)    PDF (1691KB)(130)       Save

    【Objective】 Seed soaking treatment is commonly used in potato production to promote tuber germination and bud growth. However, the improper use of seed soaking agents can trigger an imbalance of endogenous plant hormone levels, leading to the emergence of potato high-legged seedlings. In this study, the immersion effects on the growth and endogenous hormone content of potato minitubers were studied, so as to provide a theoretical basis for the safe use of chitooligosaccharide as a seed dressing agent for potato minituber. 【Method】The minitubers of Favorita were soaked with chitooligosaccharide solution at different concentrations of 10, 50, and 200 mg∙L-1 (w/v), respectively, and the most effective concentration for promoting bud growth was screened. Seeds treated with 50 mg∙L-1 (w/v) chitooligosaccharide for 15 min was the treatment group (COS50), and the negative and positive control groups were treated with distilled water (Con) and 15 mg∙L-1 gibberellin (GA3), respectively. The germination rate, germination energy, bud length and bud diameter of tubers after seed soaking treatment were determined. The content of endogenous hormones in bud tissue was analyzed by ELISA before treatment (BT), before germination stage (BGS), germination stage (GS), and vigorous growth period (VG), respectively, and the morphology of terminal bud cells of GS was observed by paraffin section staining. Pearson correlation analysis was used to determine the intrinsic differences between shoot growth and endogenous hormone content. 【Result】Seed soaking with 50 mg∙L-1 (w/v) chitooligosaccharide effectively promoted the germination and growth of tuber buds of the potato minitubers. The bud length and bud diameter of the treated samples were significantly higher than that of Con group (74.7%) and GA3 group (37.2%). On the 5th day after soaking, the tuber germination rate reached 100%, which was 40.0% and 17.0% higher than the negative and the positive control, respectively. The germination energy of the minitubers was significantly enhanced. On the 5th day after treatment, the germination energy of minituber increased by 80.0% and 28.6% compared with Con and GA3 groups, respectively. Different seed soaking treatments also showed significant differences in the endogenous hormone contents in the terminal bud meristem of minitubers. Compared with the negative control, COS50 treatment elevated the levels of auxin, cytokinin, and gibberellin in the tubers during VG period, and the contents of these hormone increased by 11.4%, 2.7%, and 2.5%, respectively, while the content of abscisic acid decreased by 3.2% (P<0.05). The positive control treatment promoted the highest levels of endogenous gibberellin, cytokinin and auxin, and COS50 treatment group had significantly lower levels of auxin, cytokinin and gibberellin than the positive control group by 5.1%, 8.4%, and 2.0%, respectively (P<0.05). No significant reduction was observed in the level of abscisic acid. However, the contents of endogenous polyamines in the apical bud meristems of the minitubers treated with COS50 was 7.0% and 2.8% higher than those in the Con and GA3 treatment groups, respectively. The results of paraffin section staining revealed that the morphological differences between the minitubers terminal bud cells was attributed to the different seed soaking treatments. The cells of the terminal bud meristem expanded resulting in elongated and flat shape in GA3 treatment, while the cells of COS50 treatment group showed a uniform shape, similar to the negative control. Furthermore, the sprouts growth, sprouts diameter, germination rate and energy of minitubers were positively correlated with the increase of cytokinin, gibberellin and polyamines contents induced by COS50 treatment (P<0.05), while abscisic acid and ployamines content were significantly negatively correlated (r=-0.785, P<0.01). 【Conclusion】Seed soaking with chitooligosaccharide increased the contents of auxin, cytokinin, gibberellin, and polyamines in sprouts of minitubers. The treatment also increased the germination rate, sprouts length and sprouts diameter of potato minitubers. Uniform enlargement of meristematic cells in the sprouts of minitubers observation showed that COS50 treatment did not affect the longitudinal elongation of apical bud meristematic cells during the expansion process, causing the bud to grow wildly. However, gibberellin content decreased significantly in seed soaked with 50 mg∙L-1 (w/v) chitooligosaccharide compared with the treatment with exogenous gibberellin 3.

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    Functional Analysis of MiZAT10A and MiZAT10B Genes in Mango
    MO WenJing,ZHU JiaWei,HE XinHua,YU HaiXia,JIANG HaiLing,QIN LiuFei,ZHANG YiLi,LI YuZe,LUO Cong
    Scientia Agricultura Sinica    2023, 56 (1): 193-202.   DOI: 10.3864/j.issn.0578-1752.2023.01.015
    Abstract262)   HTML50)    PDF (3087KB)(128)       Save

    【Objective】Zinc finger protein (ZFP) plays an important role in plant abiotic stress response. Therefore, to provide a theoretical basis for stress resistance breeding, this study aimed to analyze the response of two zinc finger protein genes of MiZAT10A and MiZAT10B transgenic Arabidopsis to abiotic stresses, such as salt, drought, heavy metals and exogenous hormones. 【Method】 The promoter cis acting elements and motif of mango MiZAT10A and MiZAT10B genes were predicted and analyzed by online software PLACE and MEME, respectively. The chromosome location map was drawn by TBtools software and SiJiMi gene annotation file (GFF file and unpublished). Tissue expression patterns of MiZAT10A and MiZAT10B genes were analyzed by qRT-PCR. The overexpression vectors of MiZAT10A and MiZAT10B genes were constructed and transformed into Arabidopsis thaliana by Agrobacterium floral-dip method. The phenotype of MiZAT10A and MiZAT10B transgenic plant were observed and recorded under salt, drought, heavy metals, abscisic acid and gibberellin treatments. 【Result】 Promoter cis element analysis showed that there were many light response elements, hormone response elements and abiotic stress response elements in the promoter region of MiZAT10A and MiZAT10B genes. Expression analysis showed that MiZAT10A and MiZAT10B were highly expressed in buds and flowers. 9 of MiZAT10A and 14 of MiZAT10B transgenic Arabidopsis strains were obtained. Overexpression of MiZAT10A and MiZAT10B significantly resulted early flowering compared with the control lines. The root length of MiZAT10A and MiZAT10B overexpressing transgenic Arabidopsis was significantly longer than that of control lines under salt stress, drought stress, heavy metal stress, GA3 and ABA hormone treatments. 【Conclusion】 Overexpression of MiZAT10A and MiZAT10B not only promoted transgenic Arabidopsis flowering early but also improved salt, drought, heavy metals and exogenous hormones GA3 and ABA resistance.

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    Effects of Chilling on Chlorophyll Fluorescence Imaging Characteristics of Leaves with Different Leaf Ages in Tomato Seedlings
    HU XueHua,LIU NingNing,TAO HuiMin,PENG KeJia,XIA Xiaojian,HU WenHai
    Scientia Agricultura Sinica    2022, 55 (24): 4969-4980.   DOI: 10.3864/j.issn.0578-1752.2022.24.014
    Abstract365)   HTML40)    PDF (1347KB)(166)       Save

    【Objective】This study analyzed the characteristics of chlorophyll fluorescence imaging of the 2nd (mature) and 4th (newly born) leaves of tomato seedlings in response to chilling stress, aiming to probe the mechanism of leaves with different ages adapted to chilling stress in tomato seedlings. 【Method】In this study, Solanum lycopersicum L. cv Zhongshu No. 4 was used as the research material. The tomato seedlings in the 4-leaf stage were treated at chilling (8℃, 200 μmol·m-2·s-1) for 15 d and then recovered at normal temperature (26℃ day/20℃ night, 500 μmol·m-2·s-1) for 1 d. The Chlorophyll fluorescence imagings of the whole seedlings were measured at different stages under different treatments, and the characteristics of chlorophyll fluorescence imaging of the 2nd and 4th leaves were compared. 【Result】The results showed that the relative area of photosynthetically active regions (RAP) on the 4th leaves decreased slowly during the first 5 d of the chilling stress, while the RAP on the 2nd leaves and the whole plants decreased steadily during the whole chilling treatment. The RAP recovered completely after 1 d of recovery. Under chilling treatment, the relative area of fluorescence active regions (RAF) for quantum yield of regulatory energy dissipation (Y(NPQ)), quantum yield of nonregulatory energy dissipation (Y(NO)), and nonphotochemical quenching (NPQ) showed similar changes as that of RAP. However, the RAF of effective PSII quantum yield (Y(II)) and coefficient of photochemical quenching (qP) were significantly lower than that of RAP. The maximum PSII quantum yield (Fv/Fm), Y(NPQ), and NPQ decreased while Y(NO) increased sharply in the photosynthetically active region in tomato seedlings during the first 5 d of the chilling treatment. In the following days, the Fv/Fm remained unchanged, whereas Y(NPQ) and NPQ increased and Y(NO) decreased. However, Y(II) declined sharply 1 d after chilling stress and then remained unchanged. Interestingly, qP in the photosynthetic active region of the 4th leaves decreased only slightly after 1 d of chilling treatment, and then maintained higher than that before treatment. However, qP of the 2nd leaves increased significantly on the 5th day and then decreased rapidly. Overall, the Fv/Fm, Y(II), Y(NPQ) and qP in the 4th leaves were higher than those in the 2nd leaves, whereas the Y(NO) were relatively lower in the 4th leaves. 【Conclusion】The study found that tomato seedlings responded to chilling stress by decreasing the area of photosynthetically active regions. The regulatory nonphotochemical quenching, which played a central role in photoprotection, was inhibited in the early stage, but gradually increased during the later stage under chilling treatment. The mature leaves adapted to chilling stress likely by decreasing the size of photosynthetically active regions, while higher capacities of PSII photochemistry and thermal dissipation were maintained in the newly born leaves in response to chilling stress. The protection of shoot apex and newly born leaves might be the priority of tomato seedlings in response to chilling stress. For newly born leaves, the chilling induced the closure of some active PSII reaction centers, but improved the operating efficiency of the remaining active PSII reaction centers, which was potentially beneficial for the recovery of photosynthetic activity.

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    Effect of Deep Tillage Under Continuous Rotary Tillage on Yield Formation of High-Quality Japonica Rice in Cold Regions
    ZHAO LiMing,HUANG AnQi,WANG YaXin,JIANG WenXin,ZHOU Hang,SHEN XueFeng,FENG NaiJie,ZHENG DianFeng
    Scientia Agricultura Sinica    2022, 55 (22): 4550-4566.   DOI: 10.3864/j.issn.0578-1752.2022.22.018
    Abstract188)   HTML31)    PDF (644KB)(114)       Save

    【Objective】 The effects of deep tillage under continuous rotary tillage on growth dynamics, photosynthetic matter production and yield formation of different japonica rice were studied in order to provide the technical support for high yield and high efficiency cultivation of high quality japonica rice in cold regions. 【Method】 A field experiment was conducted in 2018-2019, under the condition of straw returning to the field, on the basis of rotary tillage in the previous stubble for two consecutive years. Here, two tillage practices, namely, deep tillage and rotary tillage, were adopted during the growth stages of three modern japonica varieties Suijing18, Kendao12, and Sanjiang6. The effects of deep tillage and rotary tillage on the growth dynamics and post-anthesis production characteristics of high-quality japonica rice were studied. 【Result】 There was no significant difference in yield between years, but tillage methods had significant effects on the growth and development, photosynthetic dry matter production characteristics and yield characters of high-quality japonica rice in cold regions. Compared with rotary tillage, the deep tillage significantly increased the number of tillers per square meter and the number of effective panicles, the flag leaf unfolded later and lasted longer, and the heading stage was late but the duration did not change; The biomass and dry matter transport capacity of stem and sheath under deep tillage increased, and the biomass and stem-sheath dry matter transport capacity were increased by 8.34% and 5.36% respectively at full heading stage; The output, output rate and transformation rate of stem-sheath matter under deep tillage increased by 13.19%, 6.70% and 9.17%, respectively (P<0.05); The deep tillage increased the leaf area index at full heading and mature stage, prolonged the duration of green leaf area and increased the population growth rate; The internode length, leaf length and width of the third and fourth nodes of the main stem under deep tillage were increased, and the plant height and ear length were increased too; The number of grains per ear and grain weight per ear under deep tillage increased by 7.05% and 3.37%, respectively, the harvest index increased by 1.90%, and the average yield increased by 12.78%. Under the same tillage method, Kendao12 was the best in tiller number, photosynthetic matter production capacity, stem and sheath dry matter accumulation and transport capacity, yield and its composition, followed by Suijing18; However, Sanjiang6 had higher leaf area index after anthesis, grain number per panicle and grain weight at mature stage, but which could not make up for its low dry matter transport capacity, effective panicle number and 1000-grain weight. In terms of interaction effect, the combination of deep tillage × Kendao12 treatment showed higher effective panicles per square meter, strong production and transport capacity of photosynthetic matter after anthesis, high grain-leaf ratio and population growth rate, high 1000-grain weight and harvest index, reasonable allocation of plant agronomic morphological characters and coordination of yield traits, which could achieve a yield increase of 9.15%-27.47%.【Conclusion】 Continuous rotary tillage combined with one-year deep tillage was the most effective and sustainable rice tillage system to improve the yield of high-quality japonica rice in this region.

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    Effects of Flooding on Soil Chemical Properties and Microbial Community Composition on Farmland of Continuous Cropped Pepper
    GONG XiaoYa,SHI JiBo,FANG Ling,FANG YaPeng,WU FengZhi
    Scientia Agricultura Sinica    2022, 55 (12): 2472-2484.   DOI: 10.3864/j.issn.0578-1752.2022.12.017
    Abstract390)   HTML42)    PDF (1496KB)(170)       Save

    【Objective】This paper aimed to clarify the effect of farmland flooding on the soil environment of continuous pepper cropping, and to provide the technical basis for reducing the soil sickness caused by continuous pepper cropping. 【Method】In this experiment, the flooded and non-flooded soil of continuous cropped pepper in Hexian County of Anhui Province were analyzed, with non-flooded soil as control. The determination of chemical property and microbial community structure in soil with flowing analyser, qPCRand Illumina MiSeq sequencing explored the effect of flooding on the soil. Besides, the pepper was used as plant material to explore the effects of flooded and non-flooded soil on seed germination and seedling growth by the Petri dish method. 【Result】Soil flooding significantly decreased the soil EC value, organic matter, nitrate N, ammonium N, available K, and Olsen P. Quantitative PCR analysis showed that soil flooding significantly increased the bacterial community abundance (P<0.05), however decreased that of the fungal communities. Illumina MiSeq sequencing showed that the soil flooding significantly increased the relative abundances of Actinobacteria and Myxococcota, which decreased the Firmicutes and Mortierellomycota at phylum level. The soil flooding decreased the relative abundance of potential pathogenic fungi, such as Fusarium spp., positive correlation with nitrate N. The soil flooding increased potential Azotobacter, including Azoarcus, Gemmatimonas, Sideroxydans, Candidatus_Solibacter, Bryobacter, Sideroxydans spp. and plant-beneficial potential such as Aspergillus and Acremonium spp., which were negatively correlated with nitrate N. The soil microbial community structure and composition was significantly affected by soil nitrate N. In petri dish, the seed germination rate, seeding fresh weight and root length of peppers planted in flooded soil were significantly higher than those in non-flooded soil. 【Conclusion】Soil flooding significantly reduced the EC value and abundance of potentially pathogenic microbial community and increased the abundance of potentially beneficial bacterial, but significantly reduced the content of available nutrients. At the same time, Soil flooding was conducive to the seed germination and seedling growth and alleviated the pepper continuous cropping obstacles.

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    Multi-Locus Genome-Wide Association Analysis of Yield-Related Traits and Candidate Gene Prediction in Sesame (Sesamum indicum L.)
    CUI ChengQi, LIU YanYang, JIANG XiaoLin, SUN ZhiYu, DU ZhenWei, WU Ke, MEI HongXian, ZHENG YongZhan
    Scientia Agricultura Sinica    2022, 55 (1): 219-232.   DOI: 10.3864/j.issn.0578-1752.2022.01.018
    Abstract289)   HTML30)    PDF (1954KB)(139)       Save

    【Objective】 Genome-wide association studies (GWAS) were performed using multi-locus random-SNP-effect mixed linear (mrMLM) model to identify the significantly associated SNPs and candidate genes with yield traits, and lay a foundation for molecular marker-assisted selection breeding for sesame high yield.【Method】 In this study, 363 diverse sesame lines were assembled into an association-mapping panel. Eight yield-related traits, including seed yield per plant, capsule number per plant, seed number per capsule, 1000-seed weight, plant height, capsule axis length, first capsule height and apparent harvest index, were investigated. Genome-wide association studies were performed using mrMLM to detect significantly associated SNPs and predict important candidate genes related to yield traits.【Result】 Eight yield-related traits measured in four environments exhibited extensive phenotypic variation with 1.63%-17.29% of phenotypic variation coefficients. The seed yield per plant was positively correlated with capsule number per plant, plant height, capsule axis length, and apparent harvest index respectively. Analysis of variance indicated that significant variations were observed across environment, genotype, and the genotype × environment interaction. GWAS were performed and a total of 210 SNPs were detected for yield traits. Among these SNPs, 47, 35, 35, 53, and 75 SNPs were detected in 2018NY, 2019NY, 2018PY, 2019PY and BLUP, explaining 1.63%-17.29%, 1.94%-11.90%, 2.15%-15.90%, 1.25%-11.13% and 1.44%-13.58% of phenotypic variation, respectively. These 210 SNPs corresponded to 175 loci, and 10 loci were detected in more than 3 environments. A total of 214 candidate genes were identified, including 156 genes involved in metabolism, biological regulation, and developmental and growth process. Among these genes, 4 genes were selected as important candidate genes. SIN_1006338, encoding 1-aminocyclopropane-1-carboxylate synthase 3-like protein, was involved in ethylene biosynthesis. SIN_1024330, encoding transcription factor IBH1-like 1, was involved in regulating cell and organ elongation. SIN_1014512, encoding indole-3-acetic acid-amido synthetase GH3.6, was involved in shoot and hypocotyl cell elongation. SIN_1011473, encoding protein DA1-like, was involved in restricting the period of cell proliferation.【Conclusion】 One hundred and seventy-five loci were identified by mrMLM, and 4 important genes related to yield traits were selected.

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    Molecular Evolution and Function Analysis of bZIP Family in Nymphaea colorata
    YE FangTing,PAN XinFeng,MAO ZhiJun,LI ZhaoWei,FAN Kai
    Scientia Agricultura Sinica    2021, 54 (21): 4694-4708.   DOI: 10.3864/j.issn.0578-1752.2021.21.018
    Abstract510)   HTML46)    PDF (786KB)(268)       Save

    【Objective】The genome-wide analysis of the bZIP family in Nymphaea colorata was used to identify the bZIP (basic leucine zipper) family members in waterlily, and then which were further analyzed. This study revealed molecular evolution and function of the bZIP family in waterlily.【Method】The genome sequence of N. colorata was downloaded from Waterlily Pond database. The bZIP members in waterlily were identified by using HMMER 3.0 program, and the conserved bZIP domain was verified by using CDD program. The phylogenetic tree was constructed by the IQ-tree software. The ExPASy and SOPMA online website were performed to analyze protein structure characters. The conserved motifs were identified by using MEME program. The gene duplication events were found and visualized by the MCScan and Circos software. Transcriptome data of NcbZIP members were obtained from the NCBI website (SRA Study: SRP222853). The Pearson Correlation Coefficient (PCC) about the expression levels of the NcbZIP family members was calculated by using R software, and the network of the expression levels in the NcbZIP family was analyzed by using Cytoscape software.【Result】46 bZIP members were identified in N. colorata, and were named from NcbZIP01 to NcbZIP46 according to their chromosome distributions. The A subfamily contained the most NcbZIP members (11 NcbZIPs). There were 10 subfamilies (A, B, C, D, E, G, H, I, J and S) according to the phylogenetic analysis. The protein length in the NcbZIP family was from 101 aa to 1 898 aa, and the molecular weight ranged from 12.04 kD to 214.64 kD. The NcbZIP members from same subfamily had the similar distributions of the conserved motifs and gene structures. Waterlily had 14 chromosomes, and 46 NcbZIP members were unevenly distributed across 10 chromosomes. Chromosome 1 had the highest number of NcbZIP members. There were 10 gene duplication events in the NcbZIP family, including nine segmental duplication events and one tandem duplication event. The A subfamily had the most number of the gene duplication events (three). Based on the expression patterns in different tissues, the NcbZIP family could be divided into three groups (I, II and III). The NcbZIP members in Group I were highly expressed in all tissues, while the NcbZIP members in group II were not expressed in almost all tissues. The NcbZIP members in group III had tissue-specific expression profiles, and most of NcbZIP members in C, D and E subfamilies belonged to group III. The PPC analysis about the expression levels of NcbZIP members indicated NcbZIP45 had the highest connection with other members.【Conclusion】46 NcbZIP members were identified in Nymphaea colorata, and were unevenly distributed in 14 chromosomes. The NcbZIP family could be divided into 10 subfamilies with conserved motifs distributions and diverse expression levels. The current study could lay the foundation on the functional analysis of the bZIP family in N. colorata.

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    Endophytic Bacterial Community Composition and PICRUSt Gene Functions in Different Pumpkin Varieties
    HUANG ZiYue,LIU WenJun,QIN RenLiu,PANG ShiChan,XIAO Jian,YANG ShangDong
    Scientia Agricultura Sinica    2021, 54 (18): 4018-4032.   DOI: 10.3864/j.issn.0578-1752.2021.18.019
    Abstract404)   HTML40)    PDF (1081KB)(398)       Save

    【Objective】The aim of this study was to provide a theoretical basis for utilizing functional strains of endophytic bacteria in different varieties of pumpkins, as well as to explore new directions for pumpkin breeding. 【Method】The endophytic bacterial community composition and PICRUSt gene functions of 5 pumpkins varieties were analyzed based on MiSeq high-throughput sequencing results. The diversity and richness of endophytic bacterial community compositions in terms of 5 different pumpkin varieties were compared at phylum and genus levels.【Results】In total, 18 phyla, 30 classes, 101 orders, 199 families, 362 genera, 567 species and 863 OTUs could be obtained as the endophytic bacterial composition in 5 pumpkin varieties. There was no significant difference in endophytic bacteria diversity among pumpkin varieties. Significant differences in total numbers of endophytic bacteria were observed at different classification levels among pumpkin varieties. The proteobacteria was the dominant bacteria in terms of different 5 pumpkin varieties at the phylum level, but the abundance and proportion in every pumpkin variety were quite different. Moreover, Pseudomonas, Mycobacterium, Ensifer and Devosia were the dominant endophytic bacteria at genus level of different 5 pumpkin varieties, but their composition and abundance varied with pumpkin varieties. The composition and proportion of dominant endophytes at the phylum and genus level were similar between the hybrid and parent species. PICRUSt analysis also showed that endophytic bacteria inhabited in terms of different pumpkin varieties, mainly involved in 6 biological metabolic pathways and 46 sub-functions. However, there were no significant differences of endophytic bacterial genes in terms of different pumpkin varieties at the secondary functional layer. However, the numbers of gene functional copies varied with different varieties. The diversity and abundance of endophytic bacteria in terms of pumpkin were significantly affected by environmental factors. Moreover, the different endophytic bacterial community structures could be found in different pumpkin varieties. Meanwhile, a higher abundance of endophytic bacteria tended to enrich in terms of higher quality hybrids. Bacteria in 13 genera of bacteria, including Pseudomonas, Mycobacterium, Ensifer, and Devosia, etc, were the dominant endophytic bacterial genera in terms of 5 different pumpkin varieties. By contrast, Glycomyces, Candidatus_Rubidus, and Actinokineospora were the specific dominant endophytic bacterial genera in terms of Guifeng NO.7. In addition, 37 secondary functional layer functions were all the highest endophytic bacterial genes in terms of Guifeng NO.7 among the five pumpkin varieties, which involved the metabolisms of carbohydrate, amino acid, cofactors, and vitamins.【Conclusion】The higher dominant endophytic bacterial genus and the richer secondary functional genes were essential reasons for higher quality of Guifeng NO.7 than that of other four pumpkin varieties. Glycomyces, Candidatus_Rubidus, and Actinokineospora could be considered as the alternative benefit endophytic bacterial genera for improving pumpkin quality.

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    Fluorescence Characteristics Study of Nitrogen in Alleviating Premature Senescence of Spring Wheat at High Temperature After Anthesis
    JIAN TianCai,WU HongLiang,KANG JianHong,LI Xin,LIU GenHong,CHEN Zhuo,GAO Di
    Scientia Agricultura Sinica    2021, 54 (15): 3355-3368.   DOI: 10.3864/j.issn.0578-1752.2021.15.018
    Abstract323)   HTML58)    PDF (1671KB)(277)       Save

    【Objective】 The aim of this study was to investigate the influence mechanism of nitrogen on the fluorescence characteristics of spring wheat under high temperature, and to clarify the internal mechanism of nitrogen regulation of light reaction center, so as to formulate the nitrogen fertilizer operation measures to alleviate the harm of high temperature.【Method】 The experiment was carried out in 2019 and 2020, using the split-plot trial design. The main zones were 5 nitrogen application, including 0 (N0), 75 kg·hm-2(N1), 150 kg·hm-2(N2), 225 kg·hm-2 (N3), and 300 kg·hm-2(N4), and the sub-zones were temperatures of 25℃±2℃ (CK) and 35℃±2℃(HT). The interrelationships between nitrogen application and leaf nitrogen content, chlorophyll, PSⅡreaction center activity parameters, PSⅡJ phase variable fluorescence (VJ), PSⅡenergy allocation rate, PI, Fv/F0, and Fv/Fm at high post-flower temperatures were analyzed. 【Result】 The results showed that the effects of nitrogen application and temperature on leaf nitrogen, chlorophyll a, chlorophyll b, ABS/RC, DI0/RC, VJ, φE0 and φD0 and yield were significant. With the increase of nitrogen application, the yield increased first and then decreased, and reached at the highest yield under N3 with normal and high temperature treatments, which was 9.03 t·hm-2(CK) and 8.37 t·hm-2(HT). The difference between high temperature and normal temperature was obvious under different temperature treatment with the same nitrogen application, and the chlorophyll a, ABS/RC, ET0/RC, TR0/RC, PI, Fv/F0, Fv/Fm and yield decreased after high temperature treatment, which indicated that the effects of high temperature on fluorescence parameters and PSⅡactivity had negative effect. Under the treatments of different nitrogen application at the same temperature, the chlorophyll content and ABS/RC, ET0/RC, PI, Fv/F0, Fv/Fm of spring wheat increased first and then decreased, while the DI0/RC and VJ decreased first and then increased, and reached the peak at N3(225 kg·hm-2), indicating that the effects of nitrogen application on chlorophyll fluorescence parameters and PSⅡactivity had compensatory effect, and the appropriate nitrogen application amount could effectively enhance its activity. The effects of temperature on ABS/RC, TR0/RC, ET0/RC, Fv/F0 and Fv/Fm was not significant, but the interaction between nitrogen application and temperature reached significant level (P<0.05) and extremely significant level (P<0.01). 【Conclusion】 To sum up, the effects of nitrogen application and temperature on the fluorescence characteristics and yield of spring wheat was interactive, in which the dominant factor was temperature, while the amount of nitrogen application had a compensatory effect on it. A reasonable amount of nitrogen application could effectively increase the nitrogen content, chlorophyll content and PSⅡreaction center activity of wheat flag leaves, increase the capture, absorption, transformation and maximum photochemical efficiency of light energy by plants, and reduce the energy dissipation rate, so as to resist the damage caused by high temperature stress to the photosynthetic system of spring wheat. According to this test condition, the nitrogen application amount of N3 could effectively resist high temperature stress and increase the yield of spring wheat. The yield of high spring wheat could provide theoretical basis and technical support for high and stable yield of local spring wheat.

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    Investigation of miR-486 Target Genes in Skeletal Muscle of Bashbay Sheep in Different Development Periods
    ZHANG Wei,WANG ShiYin,GAO Li,YANG LiWei,DENG ShuangYi,LIU XiaoNa,SHI GuoQing,GAN ShangQuan
    Scientia Agricultura Sinica    2021, 54 (14): 3134-3148.   DOI: 10.3864/j.issn.0578-1752.2021.14.018
    Abstract378)   HTML34)    PDF (1826KB)(241)       Save

    【Objective】The aim of this study was to deeply reveal the target genes of miR-486 in skeletal muscle of Bashbay sheep during different development periods, and to get basic data for finally uncover the molecular regulation mechanism of excellent meat traits of this sheep breed, then finally to support to further breeding. 【Method】The skeletal muscle of Bashbay sheep were collected during 40 d, 50 d, 60 d, 80 d, 100 d and 120 d of fetal period, and 1, 2, and 3 months old of new born sheep. The total RNA was extracted, and two cDNA libraries of miR-486 target genes were constructed using mRNA of fetal and postnatal period, respectively, then the library was sequenced applied high-throughput sequencing technology. Based on the function analysis, 10 candidate target genes were selected, and their express patterns in Bashbay sheep skeletal muscle of 10 development periods mentioned above were detected by qRT-PCR. By analyzing the expression pattern of these 10 candidate target genes and miR-486 in skeletal muscle of Bashbay sheep, their target regulation relationship and functions were primarily verified. Finally, 4 candidate target genes were chosen to confirm their regulation relationship using the double luciferase reporter assay and target regulation assay in satellite cell of skeletal muscle of Bashbay sheep. 【Result】Total 123 and 118 target genes of fetal and postnatal period were obtained, respectively. Due to these target genes were not confirmed by further function assay, so they were called candidate target genes temporarily. Among of them, 96 genes were expressed in skeletal muscle of fetal and postnatal period, 27 and 22 genes were specially expressed in these two periods respectively. The result of GO and KEGG analysis showed that these candidate target genes regulated mass pathways related to muscle cell differentiation and development, just like PI3k-Akt, MAPK, Wnt, Adherens junction and Regulation of actin cytoskeleton, etc. All 10 candidate target genes were expressed in skeletal muscle of Bashbay sheep, but their expression patterns were different. Among of them,PTEN, Foxo1, Dock3, PAX7, IGF1R, PIK3I1 and FBN1 were expressed at a relatively high level in the fetal period skeletal muscle of Bashbay sheep, but were significantly down regulated during postnatal period, and OLFM4 showed an opposite expression pattern compared with above 7 genes. The expression of ARHGAP5 and PDCD4 gene did not found significantly change in all 10 development periods of Bashbay sheep. The result of double luciferase reporter assay showed that miR-486 could bind the target sites of PTEN, Foxo1, IGF1R and PIK3I1 efficiently, and significantly suppressed the activity of firefly luciferase. In skeletal muscle satellite cell, mir-486 also could down-regulate mRNA of these four genes significantly, and finally suppressed their biology functions. So it was ultimately confirmed that miR-486 could regulate these 4 target genes indeed in skeletal muscle of Bashbay sheep. 【Conclusion】The investigation deeply revealed the target genes of miR-486 in skeletal muscle of Bashbay sheep during different development periods for the first time, and comprehensively analyzed the biology process and signaling pathway they participated. The further function assay proved that the data of target genes were reliable. These data would help to uncover the molecular regulation mechanisms related to excellent meat traits of Bashbay sheep.

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    Genetic Analysis of Peanut Kernel Traits in a Nested-crossing Population by Major Gene Plus Polygenes Mixed Model
    ZHANG MaoNing,HUANG BingYan,MIAO LiJuan,XU Jing,SHI Lei,ZHANG ZhongXin,SUN ZiQi,LIU Hua,QI FeiYan,DONG WenZhao,ZHENG Zheng,ZHANG XinYou
    Scientia Agricultura Sinica    2021, 54 (13): 2916-2930.   DOI: 10.3864/j.issn.0578-1752.2021.13.019
    Abstract342)   HTML29)    PDF (7697KB)(242)       Save

    【Objective】Peanut kernel traits are important components of peanut yield. The genetic models of peanut kernel traits were analyzed in a peanut nested-crossing population to provide material and theoretical basis for further QTL mapping in the derived nested association mapping (NAM) population and for marker developing to assist breeding for high yield peanut varieties.【Method】The nested-crossing population containing five combinations of Yuanza 9102×Yuhua 15, Zhonghua 6×Yuhua 15, Yuhua 15×Yueyou 20, Yuhua 15×Fuhuasheng and Yuhua 15×NC94022 was constructed using Yuhua 15 as common parent and other five varieties as founder parents. A total of 1812 F2:3 families were obtained by single plant harvesting in F2, and the six kernel traits including kernel length, width, ratio of length to width, surface area, surface perimeter and average-kernel weight were measured for each family. The fitness and correlation between each pair of the traits were analyzed. The major gene plus polygene mixed genetic model of quantitative traits was tested and the genetic parameters, the number of control genes, the genetic effects and the heritability were estimated.【Result】 In the segregated populations of nested- crossing, the variation of kernel traits were extensive, and all the six traits showed normal distribution exceeding both parents in each of the combinations. There were significant correlations between each pair of the three traits including the kernel length surface area and surface perimeter. However, the correlation between kernel width and the ratio of length to width was low. The greater the correlations between each pair of the six traits, the higher the fitness. The genetic models of the kernel traits differed among the combinations. The genetic pattern of kernel surface area and kernel surface perimeter in all of the five combinations belonged to one major gene of additive-dominant model (1MG-AD), while that of the width, ratio of length to width and average kernel weight in four combinations also followed 1MG-AD pattern. The kernel length conformed to one major gene and negative completely dominant (1MG-NCD) model in three combinations, and the kernel length and ratio of length to width in one combination conformed to two major genes of equally dominant (2MG-EAD) model. The heritability of major genes was 3.80%-77.06% and the various implied the exist of multiple alleles or non-alleles in major genes as well as the minor genes in the backgrounds of different combinations.【Conclusion】Most of the kernel traits in the peanut nested-crossing population had polygenic genetic effects, and followed different genetic models. These results indicated that the genetic background of kernel traits differed in this nested-crossing population and the genetic materials will further benefit the comprehensive dissection of the genetic mechanism of complex kernel traits.

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    Analysis of Fruit Aromatic Components of Ten Plum Germplasm Resources in Northeast China
    WANG ShanShan,ZHAO ChenHui,LI HongLian,ZHANG BingBing,LIANG YingHai,SONG HongWei
    Scientia Agricultura Sinica    2021, 54 (11): 2476-2486.   DOI: 10.3864/j.issn.0578-1752.2021.11.018
    Abstract318)   HTML25)    PDF (1304KB)(323)       Save

    【Objective】In order to identify excellent plum resources with attractive aroma in Northeast China and to analyze the characteristic aromatic components for the plum fruits, ten plum germplasm resources from Northeast China were utilized to analyze their aromatic components and to identify characteristic aromatic components in their plum fruits, so as to provide reference for further molecular research and breeding application of plum aroma. 【Method】The aromatic components were determined using headspace solid phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS). Odor-activity values (OAV) and principal component analysis (PCA) were used to identify and analyze the characteristic aromatic components in the plum fruits. 【Result】A total of 63 aromatic components were identified in these ten plums. Among them, nine common aromatic components were detected in each of the ten plums, including (E)-2-hexenal, (E)-2-octenal, (E)-2-nonenal, decanal, 2-nonanone, 2,6,6-trimethyl-2-cyclohexene-1,4-dione, 2,4-di-tert-butylphenol, p-cymene, and (+) dipentene. The main aromatic components of Muhongtianli, Suilinghong, Yuejinli, Hongganhe, Huangganhe, Fortune, Great Rose, and Sifengli were aldehydes, whereas the main aromatic components of Xiangjiaoli and Niuxinli were esters. The PCA results of aromatic components showed that ten plums could be divided into three groups: the first group consisted of seven plum resources, including Muhongtianli, Suilinghong, Yuejinli, Hongganhe, Huangganhe, Fortune, Great Rose, and Sifengli; the second group consisted of only one plum resources, Xiangjiaoli, the third group was composed of only one plum, Niuxinli. According to the results of OAV values, the common characteristic aromatic components in all ten plums were (E)-2-hexenal and 2-nonanone. Other characteristic aromatic components were also detected in these plums: the characteristic aromatic components which could be detected only in Niuxinli were ethyl butyrate, ethyl caprate and isoamyl acetate; the characteristic aromatic components detected only in Xiangjiaoli were butyl acetate and hexyl propionate; the characteristic aromatic component detected only in Muhongtianli was α-pinene; the characteristic aromatic component detected only in Suilinghong was (E)-2-heptenal. 【Conclusion】β-Ionone was a characteristic aromatic component that could be detected only in seven plums distributed in Northeast China, including Muhongtianli, Suilinghong, Yuejingli, Hongganhe, Huangganhe, Xiangjiaoli, and Sifengli. Among the ten plum resources studied here, Muhongtianli, Niuxinli, and Xiangjiaoli had rich characteristic aromatic components, providing excellent plum resources with aroma.

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    Effects of Different Soybean Varieties on the Yield and Quality of Yuba
    ZENG ShiXiao,NIAN Hai,CHENG YanBo,MA QiBin,WANG Liang
    Scientia Agricultura Sinica    2021, 54 (2): 449-458.   DOI: 10.3864/j.issn.0578-1752.2021.02.019
    Abstract482)   HTML31)    PDF (563KB)(374)       Save

    【Objective】Soybean (Glycine max L.) is a crop with high economic value, as it is rich in protein and oil. The current study aimed to explore the correlations between soybean varieties and yuba yield, and the correlations between soybean varieties and yuba in the contents of protein, oil, soluble sugar and isoflavones. This study provides a reference for the production of yuba with high isoflavone. 【Method】24 different soybean varieties from Heilongjiang and Guangdong province were used to make yuba with the same processing method. Then the protein and oil content in soybean and yuba was determined by the Kjeldahl method and the Soxhlet extraction approach, respectively. The soluble sugar contents in soybean and yuba were estimated by the anthrone colorimetric method. Moreover, the isoflavones in soybean and yuba were assessed by high performance liquid chromatography. 【Result】Great difference was observed in the content of protein, oil, soluble sugar, isoflavones and yuba yield among the soybean varieties. The yuba yield from Huaxia 8 was the highest, with production rate of 60.50%, followed by Huachun 2 with production rate of 52.44%, indicating that the two varieties should be ideal varieties for producing yuba. Besides, the productivity of yuba from Suinong 37, Huachun 6 and Heihe 43 were relatively high, reaching 48.59%, 48.37% and 47.91%, respectively. Correlation analysis showed that the yuba yield was positively correlated with the protein content (r=0.598**) and negatively correlated with the soluble sugar content (r=-0.423**) in soybean. The contents of the protein, oil and isoflavones in yuba were positively correlated with those of corresponding traits in the soybean (r=0.700**, r=0.537**, r=0.879**). The soluble sugar content of yuba is positively correlated with the soluble sugar content of soybean (r=0.441*). The protein content in yuba was negatively correlated with the soluble sugar content of soybean (r=-0.519*). The oil content in yuba was significantly and negatively correlated with protein in soybean (r=-0.889**), and was positively correlated with soluble sugar and isoflavone content in soybean (r=0.614**, 0.574**), respectively. The content of isoflavones in yuba was negatively correlated with protein content in soybean (r=-0.589**), and was positively correlated with soluble sugar content in soybean (r=0.568**). 【Conclusion】 The productivity and quality traits of the yuba from soybean varieties were significantly different. Huaxia 8 and Huachun 2 were high-yielding varieties for making yuba. The quality characteristics of yuba were determined by the quality characteristics of soybean varieties, which are mainly determined by the genetic characteristics of soybean varieties.

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    Production of Citrus Triploids Based on Interploidy Crossing with Bendizao and Man Tangerines as Female Parents
    XIE KaiDong,PENG Jun,YUAN DongYa,QIANG RuiRui,XIE ShanPeng,ZHOU Rui,XIA QiangMing,WU XiaoMeng,KE FuZhi,LIU GaoPing,GROSSER Jude W,GUO WenWu
    Scientia Agricultura Sinica    2020, 53 (23): 4961-4968.   DOI: 10.3864/j.issn.0578-1752.2020.23.020
    Abstract432)   HTML9)    PDF (2575KB)(700)       Save

    【Objective】The aim of this study was to create the citrus triploids based on diploid and tetraploid ploidy cross strategy. 【Method】The artificial pollination was conducted with diploid as female parent and tetraploid as male parent. Young fruits were sampled at 85 d after pollination (DAP) and immature seeds were extracted and subjected to in vitro embryo rescue. Following plantlet regeneration from the embryos, their ploidy level was determined by flow cytometry and root-tip chromosome counting, as well as the genetic origin determined using simple sequence repeat (SSR) markers. 【Result】A total of nine interploidy crosses were carried out by using Bendizao tangerine and Man tangerine as female parents and eight allotetraploid somatic hybrids and one doubled diploids as male parents. From all crosses, 2 749 flowers were pollinated and 489 fruits were set, with an average fruit setting rate of 17.8%. By conducting in vitro immature embryo rescue, totally 260 plants were regenerated from 2 239 seeds cultured. By determining their ploidy level using flow cytometry and root-tip chromosome counting, 141 seedlings were proven to be triploids. SSR analysis showed that all of 50 randomly selected triploid plants from Man tangerine × NS were the hybrids of their both parents. After one year growing in greenhouse, all triploids were grafted onto Poncirus trifoliata in the field to accelerate flowering. 【Conclusion】These triploid citrus plants obtained herein provided elite materials for potential seedless variety selection.

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    Composition Analysis of Gas Phase and Liquid Phase of Fresh Floral Water Extract and Fresh Flowers Cell Sap from Gardenia jasminoides
    XU XiaoYu,LI AiPing,WU SiFeng,LI ChengXun,ZHENG KaiBin
    Scientia Agricultura Sinica    2020, 53 (22): 4710-4726.   DOI: 10.3864/j.issn.0578-1752.2020.22.017
    Abstract298)   HTML10)    PDF (537KB)(312)       Save

    【Objective】 In order to provide a scientific guidance for evaluating the quality of the fresh floral water extract (FFWE) and fresh flowers cell sap (FFCS) of Gardenia jasminoides and functional products development of Gardenia jasminoides flower, the comparison of component difference between the FFWE and FFCS of Gardenia jasminoides were conducted. 【Method】 The aroma components in FFWE and FFCS of Gardenia jasminoides were analyzed by headspace solid phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS). The qualitative and quantitative analyses of aroma components were carried on by computer spectrum library and artificial spectrum analysis. The chemical constituents of FFWE and FFCS of Gardenia jasminoides were analyzed by ultra high performance liquid chromatography-mass spectrometry (UPLC-ESI-QTOF-MS/MS), and then those components were identified and quantified by database comparison. 【Result】 Both the FFWE and FFCS of Gardenia jasminoides contained a large amount of linalool, their relative contents reached 63.00% and 69.37%, respectively. 79 aroma components were detected in FFWE, while 56 aroma components were detected in FFCS. 8 kinds of compounds, such as alcohols, terpenes, esters, aldehydes, ketones, and phenols, were found in both FFWE and FFCS. The total relative contents of alcohols and terpenes in FFWE and FFCS of Gardenia jasminoides reached 72.00% and 95.71%, respectively. 200, 212 and 46, 54 metabolites were identified in FFWE and FFCS of Gardenia jasminoides under the positive and negative ion mode, respectively. Under the positive and negative ion mode, FFWE and FFCS of Gardenia jasminoides were mainly comprised of alkaloids, of which the relative contents under the positive ion mode reached 47.10% and 45.21%, respectively; while under the negative ion mode were 3.21% and 13.45%, respectively. The highest relative content of the alkaloids found in both FFWE and FFCS of Gardenia jasminoides was erucicamide, which had anti-anxiety activity. More antibacterial and anti-inflammatory components, such as dihydroartemisinin, camelliagenin B, madecassic acid, and antibiotics, such as diplosporin and talaromycin A, were found in FFWE than in FFCS of Gardenia jasminoides. 【Conclusion】 The FFCS of Gardenia jasminoides had more sufficient head fragrance, but the aroma holding time was shorter than FFWE. However, the aroma components of the FFWE of Gardenia jasminoides was more abundant than that of FFCS, which had good head fragrance and bottom fragrance, and longer aroma holding time. Alkaloids were the main characteristic substances in Gardenia jasminoides flower, which could be used as evaluation index in the qualification evaluation of FFWE and FFCS of Gardenia jasminoides.

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    Development of New Varieties of ZHONGJIAO Pepper Resistant to Pepper Mild Mottle Virus Using L 3Gene
    ZHANG BaoXi,WANG LiHao,ZHANG ZhengHai,CAO YaCong,YU Hailong
    Scientia Agricultura Sinica    2020, 53 (18): 3846-3855.   DOI: 10.3864/j.issn.0578-1752.2020.18.018
    Abstract419)   HTML16)    PDF (1455KB)(527)       Save

    Hot (sweet) pepper is the largest area vegetable crop in China, with an annual planting area of 2.2×106 hm 2, including 5×105 hm2 of sweet pepper. Beside traditional diseases, in recent years, pepper milt mottle virus (PMMoV) as a new popular disease broke out, which seriously restricted the production of sweet pepper. At the same time, consumers put forward higher requirements for the quality and diversity of varieties. Our research group has introduced more than 1 400 accessions of hot (sweet) pepper germplasm resources from all over the world. Through identification and evaluation, more than 120 accessions with good characteristics such as antiviral disease, powdery mildew, large fruit, thin skin, good glossiness and high quality have been screened out. The molecular markers closely linked with TMV (L3, L4), TSWV (Tsw) and other important characters were constructed. The accuracy of assisted breeding was over 90%. Through the combination of conventional breeding techniques and molecular markers, the core backbone parental sweet pepper inbred line ‘0516’ was created with good combining ability, resistant to TMV, ToMV, PMMoV (P0,1,2), CMV and Phytophthora capsici, large fruit, uniform and good glossiness, which contained L3 gene resistant to PMMoV (P0,1,2). Four new varieties Zhongjiao 105, 106, 107 and 108 with high quality, multi resistance and adaptability to different ecological areas were developed. These new varieties contained L3 gene, which was resistant to TMV, PMMoV (P0,1,2), CMV and disease; the shape, size, color, uniformity and other commodity quality, vitamin C and other nutritional quality of fruits were significantly improved. It was important to improve the disease resistance and quality of sweet pepper.

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    Estimation of Genetic Parameters of Body Weight and Egg Number Traits of Lueyang Black-Boned Chicken
    DANG LiPing,ZHOU WenXin,LIU RuiFang,BAI Yun,WANG ZhePeng
    Scientia Agricultura Sinica    2020, 53 (17): 3620-3628.   DOI: 10.3864/j.issn.0578-1752.2020.17.018
    Abstract369)   HTML16)    PDF (733KB)(244)       Save

    【Objective】Lueyang black-boned chicken (LBC) is an indigenous breed originating from Shaanxi province of China. The breed has large adult body weight, high meat quality, abundant contents of amino acids in meat and excellent adaptation to the free-range system in the forest. But the breed has poor performance of growth and egg production. We measured body weight (BW) and egg number (EN) of LBC at different ages. Based on these phenotypic data we evaluated genetic parameters of BW and EN traits. The aim of this study is to elucidate effect of genetic factors on these traits and genetic relationship among them, thus forming a theory foundation to breeding programs of LBC.【Method】BWs at 6, 10, 14, 20 weeks of age and first egg of 799 cocks and 804 hens from 71 half-sibling families of generation 1 of LBC breeding population and individual ENs from first egg to 31, 35 and 40 weeks of age were measured. Data lower than 1st quantile-1.5×interquantile range and higher than 3rd quantile + 1.5×interquantile range was deleted prior to statistical analysis. Errors in sex records were corrected. Heritabilities were estimated using a univariate animal model where sex was designed as the fix effect, and additive genetic effect was designed as random effect. Genetic correlations among traits were estimated using a bivariate animal model. Inverse gamma distributions were used as the prior distributions for variance components of random and residual effects. Posterior distributions of variance components were obtained based on 1 000 posterior estimates which were produced using Bayesian algorithm by running 130 000 iterations of which the first 30 000 were discarded in ‘burn-in’ period and the rest was sampled every 100 iterations. Heritabilities and genetic correlations were calculated according to posterior variance components. Phenotypic correlation among traits was calculated using chart.Correlation command in PerformanceAnalytics library of R.【Result】BWs of LBC cocks were (0.56±0.07), (1.07±0.13), (1.56±0.19), (1.97±0.21) kg and BWs of hens were (0.47±0.06), (0.86±0.12), (1.18±0.16), (1.48±0.19) and (1.68±0.23) kg at 6, 10, 14, 20 weeks and first egg. ENs were 31.2±11.5, 42.5±16.7 and 54.7±20.4 at 31, 35 and 40 weeks. Heritabilities of BWs at 6, 10, 14, 20 and first egg that were 0.74, 0.76, 0.63, 0.54 and 0.52 generally decreased with increasing age. Ninety-five percent confidence interval of BW heritabilities ranged from 0.25 to 0.33. Heritabilities of ENs at 31, 35 and 40 weeks were 0.27, 0.25 and 0.26 with 95% confidence interval varying between 0.35 and 0.42. Genetic correlation among 6, 10 and 14 week BWs were moderate to high (0.52-0.68). But BWs at 6 week (0.21-0.52) and first egg (0.21-0.46) showed relatively week genetic relationship with other BWs. Ninety-five percent confidence interval of genetic correlation coefficients among BW traits ranged from 0.13 to 0.34. Genetic correlation coefficients among EN traits approached to 1 with 95% confidence interval ranging from 0.03 to 0.06. BWs and ENs did not show any significant genetic relationship. On the temporal dimension phenotypic correlation coefficients varied between 0.43 and 0.90 (P<0.001) for BW traits and between 0.79 and 0.94 (P<0.001) for EN traits. There was weak (0.023-0.15) positive correlation between BWs at 6-20 weeks and ENs. But the BW at first egg showed weak negative correlation (-0.17-0.14) with ENs. 【Conclusion】This represents the first study specifically estimating genetic parameters for LBC. The data shows that BW traits of LBC are predominately determined by genetic factors. In contrast, ENs are more influenced by environmental factors. Results from genetic correlation analysis elucidated the genetic relationship between early and late traits, and between growth and reproduction in LBC, which provide a solid foundation for early selection and multiple-trait breeding programs. High heritabilities showed by BWs suggest that the phenotypic selection of BWs could significantly increase the growth rate of LBC. However it might be more reasonable to breed pure lines and take advantage of heterosis to increase egg yield of LBS. Genetic independence between BWs and ENs suggests that it is feasible to simultaneously improve two traits in the LBC.

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    Construction and Utilization of Database for Chinese Maize Varieties and Their Genealogy
    LI JianXin,XI MengHui,ZHANG JiaWei,XI MengJuan,TIAN Ding,LU YiZhe,CHEN XiaoYang,LI WeiHua,ZHANG XueHai,TANG JiHua
    Scientia Agricultura Sinica    2020, 53 (16): 3404-3411.   DOI: 10.3864/j.issn.0578-1752.2020.16.017
    Abstract1130)   HTML37)    PDF (572KB)(501)       Save

    【Objective】 The breeding and popularization of new varieties are important for promoting the continuous improvement of maize yield in China. Breeding elite inbred lines is the prerequisite for strong heterotic combinations. To determine the kinship and genealogy relationship among maize inbred lines is the important basis for improvement of maize inbred, classification of heterotic groups and cross combination. It is imperative to sort out the genealogy of existing varieties and construct the corresponding genealogy database, so as to solve unclear consanguinity and inconvenient inquiry of maize inbred lines in China. 【Method】 A network MySQL database (https://www.maizedata.cn) of Chinese maize inbred lines, varieties and their genealogies was built based on the LNMP (Linux system, Nginx server software, MySQL database management system and PHP hypertext preprocessing software) server environment configuration. In addition, information of inbred lines and approval information of maize varieties in past years from the websites of Ministry of Agriculture and Rural Affairs of the People's Republic of China, Provincial Agricultural and Rural Affairs Departments, the big data platform of China’s seeds, as well as related literature and books were collected, collated and imported into MySQL database. Then, dream-weaving content management system (DedeCMS) was used to manage and update MySQL database. Query requests were submitted through AJAX (Asynchronous Javascript and XML) asynchronous processing, and the extracted inbred line and variety information were processed by PHP. Finally, the detailed genealogy information and genealogy tree were returned and displayed on the front-end web pages. In addition, phpMyAdmin software was applied to optimize the database structure and add new functions. 【Result】 In this database, more than 10 000 maize varieties that examined and approved by the provincial level or above, and their parents were collected, including 1218 inbred lines and 7823 varieties that have 1 to 10 pieces of information with different approved numbers and across eras in China. Variety information retrieval, genealogy tracing, filial generation query and customized query are the core functions of the database. Additionally, functions, such as addition, modification and deletion of maize inbred lines and variety pedigree information, haven been also integrated in the database. 【Conclusion】 Based on the LNMP server environment configuration, a database for Chinese maize varieties and their genealogies was constructed, which covers more than 10 000 maize varieties, including 1218 inbred lines and 7823 varieties. Core functions contain variety information retrieval, genealogy tracing, filial generation query, customized query, data uploading and updating. As an effective tool for Chinese maize breeders and researchers to quickly search the information and pedigree of maize inbred and varieties, the database can promote the breeding of elite maize inbred lines.

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    Multi-Gene-Based PCR Detection and Identification of Chilli veinal mottle virus
    YANG HongKai,YANG JingWen,SHEN JianGuo,CAI Wei,GAO FangLuan
    Scientia Agricultura Sinica    2020, 53 (16): 3412-3420.   DOI: 10.3864/j.issn.0578-1752.2020.16.018
    Abstract385)   HTML12)    PDF (1816KB)(366)       Save

    【Objective】Chilli veinal mottle virus (ChiVMV), one of the most destructive pathogens causing server losses to chilli production, is an important plant virus in port quarantine. The objective of this study is to establish a fast and accurate multi-gene-based PCR detection method for ChiVMV.【Method】DAS-ELISA and RT-PCR were used to detect the infected chilli samples imported from India. Two pairs of specific primers were designed from the conserved regions of ChiVMV coat protein (CP) and cytoplasmic inclusion protein (CI), respectively. The multi-gene-based PCR detection method was established after optimizing parameters including primer dosage and annealing temperature. The established multi-gene-based PCR detection system was also used to detect chilli viruses including ChiVMV to verify the specificity of this system, and the different concentrations of cDNA in ChiVMV positive samples were amplified to determine its sensitivity. In addition, the utility of the system was tested by detecting ChiVMV in plant samples infected by this virus.【Result】All samples reacted positive on the DAS-ELISA test. RT-PCR amplifications of the ELISA-positive subsamples all generated expected fragments of 861 bp in size, using the specific primer pair of CP861-F/CP861-R. These results indicated that all samples were infected by ChiVMV. The specific target fragments of 337 and 655 bp were respectively amplified using the primer pairs of CP337-F/CP337-R and CI655-F/CI655-R in the multi-gene-based PCR detection system, whose optimized reaction system is cDNA 2 μL, CP337-F/CP337-R 0.625 μL (10 μmol·L-1), CI655-F/CI655-R 1.375 μL (10 μmol·L-1), 2×PCR Master Mix 12.5 μL, ddH2O 6.5 μL, annealing temperature 50℃, and for 35 cycles. The established multi-gene-based PCR detection system had good specificity and sensitivity, and two targeted fragments could be detected after the total DNA was diluted to 10-4. Other ChiVMV-infected samples were successfully detected by this method, generating two expected fragments of CP and CI, respectively.【Conclusion】The established multi-gene-based PCR detection method has strong specificity, high sensitivity, excellent repeatability, which is useful in the detection and identification of ChiVMV in port quarantine.

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    Species Identification and Virulence Determination of Beauveria bassiana Strain BEdy1 from Ergania doriae yunnanus
    ZHANG Lei,JIA Qi,WU Wei,ZHAO LuPing,XUE Bing,LIU HuanHuan,SHANG Jing,YONG TaiWen,LI Qing,YANG WenYu
    Scientia Agricultura Sinica    2020, 53 (14): 2974-2982.   DOI: 10.3864/j.issn.0578-1752.2020.14.020
    Abstract422)   HTML12)    PDF (2570KB)(273)       Save

    【Objective】Ergania doriae yunnanus has become one of the main pests in soybean fields in southern China. The objective of this study is to investigate the species and biological characteristics of an entomopathogenic fungus that naturally caused the death of E. d. yunnanus, determine the virulence of this fungal strain to E. d. yunnanus adults, and to provides a new way for biological control of E. d. yunnanus.【Method】The fungus from E. d. yunnanus was isolated and purified, and the fungal DNA was extracted for amplification of rDNA-ITS. Subsequently, BLAST alignment and phylogenetic tree construction were used to identify fungal species that caused the natural death of E. d. yunnanus. The growth rate and sporulation of the fungus were measured by cross method and hemocytometer method at different culture temperatures. The virulence of fungus BEdy1 to E. d. yunnanus was assessed on the lethality of the pests by treatment with different concentrations of spore suspension and estimated by comparison with the commercial fungal agent LH. Finally, the soybean leaves sprayed with BEdy1 spore suspension were used to evaluate the lethal effect after E. d. yunnanus feeding.【Result】The fungus caused the death of E. d. yunnanus under natural conditions was identified as Beauveria bassiana, named BEdy1. BEdy1 had a high growth rate at 22-28℃, and the highest growth rate was 4.34 mm·d-1 at 26℃. There was a high sporulation at 20-26℃, and the highest sporulation was 4.63×106 spores/mm2at 22℃. The mortality at 10th day of E. d. yunnanus adults treated with 1.0×105, 1.0×106, 1.0×107 and 1.0×108 spores/mL of B. bassiana BEdy1 spore suspension was 49.33%, 77.33%, 88.67% and 98.00%, respectively. The mortality of the control treatment was only 10%. The effect was best under the treatment of 1×108 spores/mL, with the LT50 of (6.79±0.13) d and the cadaver rate of 74.67%. The LC50 and LC95 at 10th day were 4.80×104 and 3.57×107 spores/mL, respectively. Treatment with 1×108 spores/mL of a commercial B. bassiana agent LH, the mortality and cadaver rate at 10th day were only 58.00% and 4.67%, which were significantly lower than those of the same concentration of BEdy1 treatment. After 10 days of E. d. yunnanus feeding on BEdy1 treated soybean leaves, the mortality and cadaver rate were 100% and 63.33%, respectively, and the LT50 was (5.27±0.35) d. 【Conclusion】Under appropriate conditions, the B. bassiana strain BEdy1 has fast growth rate, high sporulation, and high lethality rate to E. d. yunnanus adults, which has great potential for development and application in the future.

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    Diversity of Endophytic Fungi in Transgenic Rice Seeds from Different Planting Sites Based on PTN System
    ZHAO Yan,WANG TianQi,ZHU JunLi
    Scientia Agricultura Sinica    2020, 53 (11): 2305-2320.   DOI: 10.3864/j.issn.0578-1752.2020.11.016
    Abstract303)   HTML25)    PDF (1830KB)(276)       Save

    【Objective】To provide scientific bases for study of the unintended variation in seed endophytic fungi community structure of genetically modified (GM) rice and explore the causing factors of variation, comparative analysis of the richness and biodiversity of seed endophytic fungi were conducted, using GM rice relative near-isogenic lines of different varieties in different cultivation sites as materials. 【Method】 Collect transgenic rice line which harboring the glyphosate resistant 2mG2-epsps gene (T) and its corresponding parent variety (P) and non-transgenic tissue culture regeneration control line (NR) to make parent control-transgenic plant line-non-transgenic control (PTN) near-isogenic line. The parent japonica rice Nipponbare (P1) and its corresponding transgenic line T23 and the NR control line NR18 formed the P1 near-isogenic line (P1L), the P2 near-isogenic line (P2L) composed of parent japonica rice PJ574 (P2) and its corresponding transgenic line T23 and the NR control line NR18. All rice samples were planted in two plantations including Hainan province (H) and Fuyang city of Zhejiang province (F) and the resulting seeds were harvested. The rice endophytic fungi were isolated by tissue separation method, strains were classified and identified with morphology and molecular biology methods. The isolation rate (IR), isolation frequency (IF), richness Margalef index (D), diversity Shannon-Wiener index (H') and Evenness index (E) were used to reflect the structure and distribution of rice seed endophytic fungi, and Sorenson similarity coefficient (Cs) and Fisher’s exact test were employed to describe the composition difference of endophytic fungi between rice samples. 【Result】A total of 121 endophytic fungi strains were isolated from rice seed samples of P1L and P2L near-isogenic lines that harvested in Hainan (H) and Zhejiang (F) plantations, they were identified as 15 genera, of which Curvularia, Dendryphiella, Epicoccum, Fusarium were confirmed as the dominant flora, with Fusarium as the common dominant genus of both H and F plantations. The total RF (4.61%) of endophytic fungi from Zhejiang-grown rice seeds is 5.05 times than that of Hainan-grown rice samples (0.83%). The richness Margalef index (D=2.29), Shannon-Wiener diversity index (H'=1.63) and Evenness index (E=0.66) of endophytic fungi flora from rice seeds in F plantation were higher than that (D=1.67, H'=0.63, E=0.29) of samples in H plantation. The seed endophytic fungi communities of P1L and P2L in H plantation had a similarity coefficient of 0.615, and that was 0.737 in F plantation, showing moderate similarity, and the Fisher’s exact test analysis suggested that there were no significant difference (P>0.05) between them. The GM lines except HT16 showed moderate similarity to their corresponding parent controls referring seed endophytic fungi communities, with similarity coefficient ranged between 0.500 and 0.667. But compared with their corresponding parents, the GM rice lines showed notably unintended variations in IF and genus numbers of endophytic fungi, the variation direction and amplitude of IF varied between different plantations. Also, the GM line FT16 increased 2 additional fungi genera Phaeosphaeria and Nigrospora, HT23 and FT23 respectively added 1 genus Letendraea helminthicola and 2 genera including Curvularia and Cladosporium. These genera increasing variations of endophytic fungi in GM rice seeds were derived from transgenic insertion mutation, whose safety needs to be focused on. While the genera decreasing variations of endophytic fungi in GM rice seeds were derived from somaclonal variation of tissue culture, which were safer. The variation amplitude order of total IF of rice endophytic fungi were as follows. Difference between H and F plantations referring to P1 and P2 (30.58%)>Difference between P1 and P2 varieties (27.28%)>Variation of NR lines (23.14%)>Variation of GM lines (22.32%). The genus number variations of rice endophytic fungi ranked as follows. Difference between H and F plantations referring to P1 and P2 (9)>Difference between P1 and P2 varieties (8) = Variation of NR lines (8) = Variation of GM lines (8). 【Conclusion】Rice seeds have abundant and diverse endophytic fungi, with majority of the culturable stains belong to Ascomycetes. Composition of rice seed endophytic fungi community shows geographical differences, and Fusarium is very common dominant genus in rice seeds grown both in Hainan and Zhejiang. The structure of endophytic fungi flora in rice seeds are affected by transgenic manipulation as well as tissue culture technology, while their unintended variation effects are less than that of rice growing locations and variety differences. The genera increasing variations of endophytic fungi in GM rice seeds are derived from transgenic insertion mutation, and the safety needs to be assessed.

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    Effect of Recombinant GSTA3 Protein on Expression of the Anti-Apoptotic Gene BAG-3 in Thiram-Induced Tibial Chondrodysplasia
    Zhen LI,ShiXiong YANG,Sheng NIU,Ning ZHANG,Xin LI,YangYang ZHANG,YunFei JIA,ZhiXiong TIAN,GuanBao NING,Ding ZHANG,WenXia TIAN
    Scientia Agricultura Sinica    2020, 53 (9): 1921-1930.   DOI: 10.3864/j.issn.0578-1752.2020.09.018
    Abstract300)   HTML29)    PDF (2437KB)(243)       Save

    【Objective】Tibial chondrodysplasia (TD) is a common skeletal disease in broilers. The study was conducted to investigate the effect of recombinant GSTA3 protein on the expression of anti-apoptotic gene BAG-3 in the chondrocytes of broilers induced by thiram, so as to provide a new idea and method for the treatment of TD. 【Method】120 one-week-old broiler chicks were randomly divided into six groups (A, B, C, D, E and F), in which Group A, B and C were basic diet groups, and group D, E and F were thiram-containing diet groups. TD was induced by thiram for 2 days. After thiram was added for days 1, 3, 5 and 7, recombinant chicken GSTA3 protein and phosphate buffer were injected into the leg muscles. Group A and group D were injected with PBS (100 μg·kg -1); group B and group E were injected with low dose (100 μg·kg -1) GSTA3; group C and group F were injected with high dose (200 μg·kg -1) GSTA3. The experiment lasted 23 days. Tibia growth plates were collected at the 1st, 2nd, 4th, 6th, 10th and 15th days after thiram treatment. The mRNA level of BAG-3 gene was detected by quantitative PCR, and the protein expression of BAG-3 gene was observed by immunohistochemistry. 【Result】Real-time PCR results showed that the expression level of BAG-3 mRNA in tibia growth plate of broilers in the thiram-containing diet group was significantly increased, compared with that in the basal diet control group during the repair period of TD injury (P<0.05). Compared with the thiram-containing diet group, E and F groups had significant differences on days 2, 4, 10 and 15, and were significantly lower than that under the thiram-containing diet group on days 10 and 15 (P<0.05), indicating a faster recovery compared with group D. Immunohistochemical results showed that BAG-3 protein was not expressed in the proliferation area and the pre-hypertrophic area of the chicken tibial chondrocytes, but only in the cytoplasm of the hypertrophic area. Compared with the control group A, the expression of BAG-3 protein in the thiram-containing diet group was increased. The recombinant GSTA3 induced the protein expression level in the hypertrophic area in the high and low dose of GSTA3 group compared with the thiram-containing diet group D (days 10 and 15). 【Conclusion】In conclusion, GSTA3 recombinant protein could regulate the expression of BAG-3 to participate in the apoptosis pathway and inhibit the apoptosis during the induction of TD in broilers. During the TD-injury repair period, after GSTA3 injection, the expression of anti-apoptotic gene BAG-3 protein was enhanced, which could participate in cell apoptosis to alleviate the TD-injury and make the TD growth plate function of broilers return to normal quickly.

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    Genetic Diversity of Dactylobotrys graminicola and Its Pathogenicity to Hordeum vulgare var. nudum Seedlings
    Lin CHEN,RuiMing LIN,FengTao WANG,YunXing PANG,Xue LI,AiPing ZHAO,YanXia ZHANG,JinLing ZHANG,WenXing LI,SuQin HE,Jing FENG,Yun LI,CaiYi WEN,ShiChang XU
    Scientia Agricultura Sinica    2020, 53 (1): 213-224.   DOI: 10.3864/j.issn.0578-1752.2020.01.020
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    【Background】In the high-latitude agricultural areas of Qinghai-Tibet Plateau and its peripheral regions, hulless or naked barley (Hordeum vulgare var. nudum) is the only small grain cereal crop in the local area, and it is also the major forage. Dactylobotrys spike blight, caused by Dactylobotrys graminicola, is a new fungal disease only found in the hulless barley growing areas in Qinghai-Tibet Plateau in recent years, which can attack several triticeae crops and cereal grasses and make a great challenge to security of hulless barley production.【Objective】The objective of this study is to research the genetic diversity, systemic evolution of the fungal pathogen of D. graminicola and its effects on the host seed germination, reveal the pathogen epidemics and spread ways, host-pathogen interrelationship and the primary inoculum, and to provide valuable information for disease control.【Method】The diseased plant samples were collected from the disease epidemic areas, and 27 strains were isolated from the typical infected host spike tissues. After identification based on its biological traits of anamorph, the single-conidium strains were cultivated and used for genomic DNA extraction. The whole genomic diversity was evaluated with SRAP markers and strain-specific markers were developed. The evolution relationship between D. graminicola and its related genera or species was analyzed using the two conserved loci of LSU and Rpb2. The conidium suspension was co-cultivated with the germinated or ungerminated hulless barely seeds, and its effect on barley seed germination and seedling growth of hulless barely was analyzed.【Result】Fourteen SRAP primer combinations were selected to detect genetic diversity of D. graminicola strains, and on average, 90 polymorphic DNA bands were produced per primer combination. For D. graminicola strains, only 1.4 strain-specific markers were developed averagely. The strain of Z 13008 derived from common wheat possessed the most 7 SRAP markers. For Fusarium graminearum used as a control strain, 20 specific markers were identified. It was confirmed that there is no close relationship between strain origins of D. graminicola and their genetic diversity. Among the identified strains, only those like Z 13008 from common wheat, Z 13024 from rye and another two (Z 13013 and Z 13006) from hulless barley showed higher differences in genetic diversity compared with the others, indicating that the genetic variation level of D. graminicola population is low. Besides, it is feasible to characterize the 21 D. graminicola strains with a DNA dichotomous fingerprinting key constructed with 20 SRAP markers. D. graminicola is genetically closely related to the fungal species of genus Nectria through phylogenetic analysis. When inoculating seeds with conidial suspensions before germination, the pathogen had no significant suppression on seed germination and growth of seedlings and their roots. While it could infect and restrain seedling root growth when co-cultivating the germinated seeds with conidial suspensions, and resulted in the infected young roots changing into light brown color, but had no significant effect on seeding growth.【Conclusion】D. graminicola showed lower genetic diversity compared with its relative species of F. graminearum, and its genetic variation is closely related to its host plant species. The pathogenicity of the pathogen is weak, and it has no obvious inhibiting effect on the germination and seedling growth of hulless barley.

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    Phenotype Character Analysis and Evaluation of Modern Rose Cultivars
    Cong GUO,Wei GUAN,XiangGuo ZENG,QingHua ZHANG,FaYun XIANG,YueJun SONG,YongChao HAN
    Scientia Agricultura Sinica    2019, 52 (24): 4632-4646.   DOI: 10.3864/j.issn.0578-1752.2019.24.017
    Abstract476)   HTML18)    PDF (2053KB)(441)       Save

    【Objective】The objective of this study was to analyze 11 phenotype indexes of 60 rose cultivars and to illustrate the variation rules and the genetic diversity coefficient of each index and the correlation between them. The principal component analysis was used to select an optimal evaluation and calculation method to provide reference for rational clustering of rose cultivars. 【Method】Taking 11 statistical characters of 60 modern rose cultivars in field as the research object, the variation index and Shannon-wiener genetic diversity index of each character data in rose cultivars were analyzed with SPSS19.0 and Microsoft Excel 2007, and the correlation analysis and principal component analysis of each character were carried out. Based on the composite score of principal components and each principal component score, the clustering of the rose cultivars were done.【Result】The statistical results of phenotypic traits showed that, the majority of the tested roses were erect and expanded shrubs, which accounted for 53% and 35% of the total cultivars respectively. The number of leaflets of mature leaves was 5, accounting for 68% of total cultivars. The average whole leaf length, top leaflet width, internode length and average flower diameter of 60 rose cultivars were 11.6, 3.2, 3.6 and 7.6 cm, respectively. The variation coefficient of each quantitative index ranged from 21% to 25%, which was not large. The main color of rose was pure color, accounting for 82% of the total. Among them, purple and yellow flowers were the most. The cultivars with successive flower heads accounted for 65% of the total number, and the flower shapes were mainly ball-shaped and cup-shaped, accounting for 33% and 32% of the total cultivars, respectively. The main senescence modes of rose flowers were petal abscission and flower withering, accounting for 47% and 43% of the total cultivars, respectively. The variation range of the genetic diversity coefficient of each index was between 0.62 and 3.73, among which the diversity index of 8 traits was above 1, the highest was the whole leaf length, and the lowest was the leaflet number. The genetic diversity coefficient of flower color among qualitative traits was the highest. There was an extremely significant positive correlation between whole leaf length and the top leaflet width, the internode length and the whole leaf length, the internode length and the top leaflet width. The flower head number was very significantly negatively correlated with the internode length. There was a significantly positive correlation between the senescence type and the growth habit, the number of flower heads was significantly positive correlated with the number of leaflets and the flower type, but significantly negative correlated with the flower diameter. The results of principal component analysis showed that the 11 phenotype indexes could be simplified into 4 principal component factors, and the variance contribution rate of the 4 principal components was up to 63.28%, among which the variance contribution rate of the first principal component was up to 21.1%. Each principal component factor mainly represented the index variables, such as leaf shape, flower shape, number of flower heads, number of petals and flower aging mode. Based on the composite score of principal components and each principal component score, the 60 cultivars of roses were clustered, and the distribution range of the composite score of principal components of each cultivar was from -1.878 to 1.522. The rose cultivars could be divided into 4 clusters according to the scores, and each cluster was represented by 8, 36, 15 and 1 cultivars, respectively. The classification of each cluster reflected the comprehensive performance of roses in the field. 【Conclusion】Modern rose had a rich diversity of flower color and leaf shape indexes, and some flower shape indexes were significantly related to leaf shape or growth habit. The conclusions would contribute to rose breeding and selecting. The four principal component indexes and the clustering of cultivars selected in the study provided theoretical basis for the preservation and application of the existing rose cultivars.

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    Molecular Cloning, Prokaryotic Expression and Binding Characterization of Odorant Binding Protein GdauOBP20 in Galeruca daurica
    Ling LI,Yao TAN,XiaoRong ZHOU,BaoPing PANG
    Scientia Agricultura Sinica    2019, 52 (20): 3705-3712.   DOI: 10.3864/j.issn.0578-1752.2019.20.020
    Abstract346)   HTML9)    PDF (1588KB)(413)       Save

    【Objective】 Galeruca daurica is a new pest with outbreak status in the Inner Mongolia grasslands in recent years. The objective of this study is to clone the full-length cDNA sequence of GdauOBP20, and clarify the binding property of the recombinant protein to main host plant volatiles, which will lay a necessary foundation for revealing the molecular mechanism of olfaction in G. daurica.【Method】 RACE technique was used to clone the full-length cDNA of GdauOBP20 based on the transcriptome database of G. daurica. The physicochemical properties and structural characteristics of the encoded protein were predicted and analyzed by bioinformatics software. The recombinant protein GdauOBP20 was induced to express by constructing prokaryotic expression system, and purified by using the Ni-NTA Agarose affinity column. Finally, the fluorescence competitive assay was applied, and N-phenyl-1-naphthylamine (1-NPN) was selected as the fluorescence probe to measure the binding profiles of GdauOBP20 recombinant protein with 13 main host plant volatiles.【Result】 The full-length cDNA of GdauOBP20 is 567 bp (GenBank accession number: MK250532), with the non-coding regions of 5′ and 3′ ends of 24 bp and 123 bp, respectively, and a ployA tail structure. The open reading frame (ORF) is 420 bp, encoding 139 amino acids. The amino acid sequence of GdauOBP20 contains 4 conserved cysteine residues, indicating that it belongs to Minus-C OBP subfamily. The three-dimensional structure prediction of GdauOBP20 contains six alpha helix and two pairs of disulfide bonds formed by cysteine. The recombinant expression vector was successfully constructed, and the recombinant protein with high purity was obtained. The binding capacity of the recombinant protein GdauOBP20 to the fluorescence probe 1-NPN was strong with a binding constant of 12.8 μmol·L -1, indicating that it could be used as the fluorescence reporter in this experiment. Affinities of recombinant protein GdauOBP20 with 13 main host plant volatiles were tested. Among them, except diallyl trisulfide, other 12 volatiles showed certain binding capacities with the recombinant protein, and p-xylene and 1,3,5-cycloheptatriene displayed the strongest affinity with the dissociation constants of 22.91 and 26.55 μmol·L -1, respectively, whereas myrcene exhibited the weakest binding affinity with the dissociation constant of 116.29 μmol·L -1.【Conclusion】 GdauOBP20 has a certain binding capacity with main host plant volatiles, suggesting that it may play an important role in the localization of host plants.

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    Artificial Simulation of Hill-Drop Drilling Mechanical Technology to Improve Yield and Lodging Resistance of Early Season Indica Rice
    YI YanHong,WANG WenXia,ZENG YongJun,TAN XueMing,WU ZiMing,CHEN XiongFei,PAN XiaoHua,SHI QingHua,ZENG YanHua
    Scientia Agricultura Sinica    2019, 52 (15): 2729-2742.   DOI: 10.3864/j.issn.0578-1752.2019.15.016
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    【Objective】This study investigated the effects of hill-drop drilling mechanical technology with furrowing on the yield-related traits and lodging resistance of early season indica rice, which provided theoretical basis and technical support for the mechanical direct-seeding technology. 【Method】Two indica rice varieties, including inbred rice Zhongjiazao17 and hybrid rice Zhuliangyou171, with three treatments (hill-drop drilling mechanical technology with furrowing (MFP), surface bunch planting (SBP) and soil covering bunch planting (SCP)) were used to compare the effects on seedling emergence rate, yield-related traits and lodging resistance of rice. 【Result】The results showed that compared with SBP and SCP, MFP increased seedling emergence rate of early season indica rice by 5.19% to 13.89%, and the difference was significant (P<0.05). At the same time, MFP was conducive to improving yield of direct seeding rice. Yield increase rate of the two varieties was ranged from 4.52% to 11.20%, and yield of inbred rice Zhongjiazao17 was significantly different to the others. From the analysis of yield components, the increase in yield was mainly due to the synergistic improvement of effective panicles per unit area and 1000-grain weight. In addition, MFP was beneficial to improve resistance of plant and reduce lodging index, especially the upper internode, and it was beneficial to increase height, gravity center height, culm wall thickness and internode diameter of upper internode (I3), and increase dry weight per unit length of internode, dry weight per unit volume of internode and lignin. There was positive correlation between internode dry weight and breaking resistance, and negative correlation with lodging index. Therefore, dry weight, and dry weight per unit length of internode were the main factors for affecting lodging. Plant height, gravity center height, internode length and internode diameter could not both affect lodging resistance and lodging index. 【Conclusion】 MFP could improve the grain yield of direct seeding early indica rice, and also enhance plant lodging resistance, decrease lodging risk. It could be popularized in the production.

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    The Correlation Between the Stress Relaxation Characteristics and the Quality of ‘Haiwode’ Kiwifruit
    LU Dan,ZHAO WuQi,ZENG XiangYuan,WU Ni,GAO GuiTian,ZHANG QingAn,ZHANG BaoShan,LEI YuShan
    Scientia Agricultura Sinica    2019, 52 (14): 2548-2558.   DOI: 10.3864/j.issn.0578-1752.2019.14.013
    Abstract279)   HTML15)    PDF (414KB)(300)       Save

    【Objective】This study aimed to extract the quality properties of Haiwode kiwifruit, and to make further effort to investigate the correlation between its stress relaxation and the quality properties. In addition, a rapid analysis method was considered for quickly predicting the quality properties of kiwifruit by using the mechanical characteristics of kiwifruit.【Method】This study measured the nutrition compositions, color, texture and other indicators of the kiwifruit at the different storage periods, then the factor analysis was applied to select the real quality properties of the kiwifruit, and the model of the stress relaxation was established and the correlation analysis was conducted between the model of stress relaxation and the real quality properties of the kiwifruit. Finally, the mathematical model of stress relaxation predicting the quality features of kiwifruit was obtained by the ridge regression with a final verification. 【Result】The Maxwell model with seven components could better describe the stress relaxation of the kiwifruit, and the coefficient of determination of the fit reached 0.999. The Vc, soluble solids and ΔE had significantly positive correlation with elastic parameters and viscosity coefficients (P<0.05). Vc and E0, ΔE and E0 had a correlation coefficients of 0.901 and 0.813, respectively. The texture indexes of hardness, elasticity and cohesiveness were also highly correlated with elastic parameters and viscosity coefficients (P<0.05). The correlation coefficients between the hardness and η1, the springiness and E0 were 0.807 and 0.951, respectively. The decision coefficients of the Vc, soluble solids, ΔE, hardness (TPA), cohesion and springiness using in the prediction model were of 0.906, 0.717, 0.883, 0.709, 0.708 and 0.851, respectively. And all of them had a great statistical significance (P<0.05). The results show that the decision coefficients between the model predicted values and the measured values to the validation collection were of 0.882, 0.880, 0.869, 0.690, 0.733 and 0.814, respectively. The t-test values were all less than 2.145, indicating that there were no significant differences between the predicted values and the measured values. 【Conclusion】 The results showed that the stress features of the Haiwode kiwifruit were significantly correlated with its quality features. Thus, the mathematical model of stress relaxation constructed by the ridge regression method could accurately predict the quality features of kiwifruit, providing a theoretical basis for the evaluation of the kiwifruit quality during storage period.

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    Cloning and Expression Analysis of Jasmonic Acid Carboxyl Methyltransferase Gene from Perilla frutescens
    BAI HuiYang, LU Geng, LU JunXing, GUAN Li, TANG Xin, ZHANG Tao
    Scientia Agricultura Sinica    2019, 52 (9): 1657-1666.   DOI: 10.3864/j.issn.0578-1752.2019.09.016
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    【Objective】Jasmonic acid carboxyl methyltransferase (JMT) is a key enzyme in the biosynthesis of methyl jasmonate. By cloning the Perilla frutescens JMT and studying its expression patterns under different stresses and different developmental stages of seeds, it provides a theoretical basis for studying the role of JMT in plant defense and seed development.【Method】Primers were designed based on the transcriptome sequencing results of Perilla seeds, and the DNA and cDNA sequences of the JMT were cloned from Perilla, named PfJMT. Analysis of the structure, stability, hydrophilicity, subcellular localization and conserved domain of PfJMT by bioinformatics methods. Analysis of the evolutionary relationship between PfJMT and other species JMT proteins using phylogenetic tree. Tissues such as perilla roots, stems, leaves, and flowers in flowering stage were used for tissue-specific expression analysis. Seeds at 5, 10, 15, 20, 25, and 30 days after flowering were used for the study of JMT expression patterns in different developmental stages of seeds. The perilla seedlings with 4 true leaves were sprayed with 25 μmol·L -1 methyl jasmonate (MeJA) and 1 mmol·L -1 salicylic acid (SA) and the roots were watered, perilla root and leaf tissues from different individuals were taken after 0, 2, 4, 8, 16, 24, and 48 hours of treatment to study the expression pattern of JMT under different stresses.【Result】PfJMT has an ORF of 1 050 bp and encodes 349 amino acids. Bioinformatics analysis showed that PfJMT is an unstable hydrophilic protein, which is located in the cytoplasm and contains a Methyltransf-7 conserved domain. Compared with the JMT protein sequence of other species, the sequence identity of Perilla JMT and Salvia miltiorrhiza JMT was the highest, which was 80.5%, and the sequence with Oryza sativa Japonica Group was the lowest, which was 36.8%. In the analysis of phylogenetic tree based on JMT protein construction system in many different plants, it was found that the dicotyledonous plants such as Perilla and Arabidopsis thaliana and Salvia miltiorrhiza were closely related, but the relationship with the monocotyledons such as Cymbidium ensifolium and Oryza sativa Japonica Group was far. This indicates that JMT may have large differences in the evolution of monocotyledonous and dicotyledonous plants. The results of real-time PCR showed that the relative expression of PfJMT in roots and stems of Perilla was the lowest, leaves and flowers was slightly higher, 5 days after flowering was the highest, and it was gradually down-regulated with the development of seeds. This indicates that JMT plays an important role in seed development. PfJMT expression was significantly down-regulated in Perilla root and leaf tissues treated with MeJA and SA. This result supports the theory that JMT may not directly participate in defense responses, but indirectly participate in plant defense by regulating JA levels.【Conclusion】PfJMT was successfully cloned, and the expression of PfJMT was gradually down-regulated with the development of seeds, and the expression level was significantly down-regulated under exogenous MeJA and SA stress.

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    Genetic Analysis of Sex-Linked Plumage Color Traits of Goose
    YU JinCheng,LI Zhe,YU Ning,LIU Kuang,ZHAO Hui
    Scientia Agricultura Sinica    2019, 52 (5): 949-954.   DOI: 10.3864/j.issn.0578-1752.2019.05.016
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    【Objective】The Huoyan breed of geese is a famous white goose breed in China, 1-day-old gosling of the Huoyan goose are yellow or light yellow. In the offspring of the free mating group, 20% of 1-day-old goslings were found to have a light brown variation during Huoyan goose breeding process, and the ratio of male to female is obviously different (the ratio of male to female is close to 1﹕3), it is speculated that there is a sex-linked inheritance tendency in goose plumage color trait. Using the light brown male geese and yellow female geese as the parents, the hybrid experiment was used to test whether the phenotype of the gosling downy feathers conformed to the Mendelian inheritance law, so as to understand the genetic mechanism of goose plumage color trait. The study on the inheritance and mechanism of feather color traits of goose is of great significance for the breeding of new breeds or strains of goose and the goose specialized line cultivation of auto-sexing by feather color. 【Method】40 males and 200 females of Huoyan geese were chosen to generate the G1 generation of Huoyan goose pure line by random mating, and plumage color appearance and segregation ratio in G1 were observed. 4 light brown males and 20 white feather color females of Huoyan geese were chosen to generate the F1 generation, and plumage color appearance and segregation ratio in F1 were observed. 【Result】① In the random mating G1 generation of the Huoyan goose, the proportion of light brown downy feather trait individuals was 19.5%. Among them, the ratio of light brown individuals between male and female chicks is relatively large, the proportion of light brown in male chicks is about 10%, and 30% of females are light brown. According to Hardy-Weinberg’s law, the allele frequency of the color traits of the downy feather is calculated as follows: The ratio of light brown individuals in the female goslings is the frequency of the light brown trait alleles in the Huoyan goose population, in this experiment, 29.8% of the female are light brown, so the frequency of the light brown trait allele is about 0.3. At the same time, the ratio of the light brown individual in the male goslings can also calculate the frequency of the light brown allele, in this case, 10% of the male are light brown, so the frequency of the light brown trait allele is about 0.3. Correspondingly, the frequency of the yellow downy feather trait allele is about 0.7. ②Among the F1 populations, 81 were yellow feathers, accounting for 50%; 79 were light brown, accounting for 50%. And the yellow feathers are all male, and the light brown feathers are all female. The results showed that the light brown traits were associated with sex-linked inheritance. It has been confirmed that silver feather (S*S) and imperfect albinism (S*AL) are controlled by a pair of alleles located on the Z chromosome, and the imperfect albinism gene AL is recessive to the silver feather gene S. Therefore, based on the results of the hybridization test, it can be concluded that the light brown and yellow are the results determined by the multiple allele of one locus, and the light brown color is recessive inheritance for the yellow trait.【Conclusion】In this experiment, the separation of 1-day-old goslings feather phenotypes was analyzed by downy feather color matching hybridization and random mating test. The results showed that the light brown downy feather color trait of Huoyan goose exhibits recessive heredity to the yellow, and demonstrates sex-linked inheritance. The downy feather color of the Huoyan goose is mainly controlled by the Z chromosome silver feather locus. The variation site of the allele controlling the locus is associated with the corresponding appearance.

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    Genetic Diversity of the Prunus salicina L. from Different Sources and Their Related Species
    WEI Xiao,ZHANG QiuPing,LIU Ning,ZHANG YuPing,XU Ming,LIU Shuo,ZHANG YuJun,MA XiaoXue,LIU WeiSheng
    Scientia Agricultura Sinica    2019, 52 (3): 568-578.   DOI: 10.3864/j.issn.0578-1752.2019.03.017
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    【Objective】 There are abundant Japanese plums (Prunus salicina L.) germplasm resources in China, which are distributed widely in geography. The better understanding of the diversity, the genetic structure and the relationship between sympatric related species, can be helpful to clarify the process of domestication of the cultivated groups of plum and the role of the related species, also further contribute to the in-depth exploration of local resources and enhance the fruit quality in breeding. 【Method】 The 22 pairs of SSR markers covering the entire genome were used to scan 48 samples, including 38 accessions of P. salicina from different sources and 10 accessions of the variation types or related species, by high-throughput fluorescence capillary electrophoresis platform. The polymorphism of 22 SSR loci and genetic diversity of 48 samples were evaluated via the software GenAlEx 6.41, and the dendrogram of these accessions was constructed by using the NTSYS-pc Version 2.1 program. The STRUCTURE 2.2 software based on Bayesian clustering method was used to analyze the genetic mixture of samples and to perform an assignment test on the studied individuals. 【Result】 The detected alleles of 22 SSR primers ranged from 3 to 21, with an average of 13.54 alleles for each locus. A total of 298 alleles were detected in these accessions, 51.8% of which were rare alleles. The values of average effective allele (Ne), average Shannon's diversity index (I), observation heterozygosity (Ho) and expectation heterozygosity (He) indicated that the diversity was the highest in the southern population, followed by the northeast population, which also indicated that the diversity of the Prunus simonii was lower than that of northern China. The analysis of molecular variance (AMOVA) showed that 69% of the diversity in P. salicina was within the population, and only 31% was among populations. On the basis of the data comparisons of the genetic differentiation coefficient and Nei's genetic distance, the results showed that there were extremely significant genetic differentiation and appropriate genes mixture among different geographical populations. The results of cluster analysis implied that the breeding cultivars abroad were closely related to the local accessions in southern China, and the northern cultivars population was similar with P. simonii, the northeast cultivars population had close relationship with Prunus ussuriensis. The genetic structure analysis indicated that the accessions in P. salicina were divided into four types: northern cultivars population, northeast cultivars population, southern cultivars of small fruit and crisp meat population, and southern cultivars of large fruit population (including foreign breeding cultivars). 【Conclusion】 The diversity of the southern varieties were the most abundant in the P. salicina, followed by that of Northeast China varieties, foreign varieties and Northern varieties. In order to enhance the adaptability, the northeast population might be introgressed with P. ussuriensis. P. simonii might be a special type which was highly domesticated from Chinese plum in Northern China, and it had high heterozygosis owing to asexual reproduction by grafting. The large fruit accessions in Jiangsu and Zhejiang regions played an important role in modern breeding varieties abroad.

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    Effect of Root Irrigation of Acetic Acid and Wine on Photoinhibition of Grape Under Seawater Stress
    Hui WANG,YuLu GAO,Meng YU,YuanPeng DU,YongJiang SUN,Heng ZHAI
    Scientia Agricultura Sinica    2018, 51 (21): 4210-4218.   DOI: 10.3864/j.issn.0578-1752.2018.21.019
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    【Objective】In order to expand the effective utilization of salinized soil and improve the quality of grape growth and development in salinized soil, the effects of acetic acid and wine on leaf photoinhibition under 15% seawater stress were studied. The result will provide a theoretical basis and technical reference for the improvement of grape cultivation techniques in salinized soil. 【Method】One-year old potted ‘Moldova’ seedlings were grown in plastic pots (with a diameter of 20 cm, and a height of 18 cm). The ratio of soil to substrate in each pot was 1﹕1 and the pots were placed in greenhouse. The culture conditions of the greenhouse were as follows: the average daily temperature was about 25℃, the light transmittance was more than 50% of natural light intensity, the maximum light intensity was 800 μmol·m -2·s -1, the relative humidity was 40%-60%, and the normal fertilizer and water was managed until 8-10 pieces of fully expanded leaves, then the seawater and exogenous acetic acid were used. The plants were irrigated with 15% seawater, 30 mmol·L -1 exogenous acetic acid and 2% wine at the same time, each treatment repeated 5 times, the controls were treated with clear water. Each treatment was irrigated every 2 days and 3 times, the irrigation amount was 2 times of water holding capacity, and about 1/3 of the solution leaked out, chlorophyll fluorescence indicators were determined on the 2nd day of irrigation, after 10 days treatment, the effects of the two methods on malondialdehyde (MDA) content, chlorophyll content, and root activity under seawater stress were analyzed.【Result】15% seawater treatment significantly decreased the chlorophyll content of leaf and root activity, but increased MDA content of root, stem and leaf. Compared with clear water control, the chlorophyll content decreased by 18.5% and root activity decreased by 41.9%. MDA content of root, stem and leaf increased by 1.10, 0.27 and 0.41 times, respectively. However, 30 mmol·L -1 acetic acid and 2% wine treatments significantly decreased the MDA content in grape. The MDA content in root, stem and leaf of grape treated with acetic acid decreased by 29.3%, 20.6% and 15.8%, respectively, compared with that of seawater stress, and the MDA content in root, stem and leaf of grape treated with wine decreased by 29.4%, 20.2% and 25.2%, respectively, compared with that of seawater stress. Irrigated with acetic acid and wine significantly increased the leaf chlorophyll content and root activity. Compared with seawater stress treatment, the root activity increased by 68.4% and 56.9%, and the chlorophyll content increased by 18.8% and 20.3%, respectively. The analysis of chlorophyll fluorescence showed that 15% seawater treatment decreased the levels of photosystem II (PSII) maximum photochemical efficiency (Fv/Fm) and the maximum photo-oxidizable P700 (Pm). The Pm on the 3rd, 6th, and 9th day decreased by 5.0%, 9.6% and 13.0% compared with the control, the levels of photochemical quenching coefficient (qP) and PSII actual photochemical efficiency (YII) decreased gradually, but the quantum yield of regulated energy dissipation Y (NPQ) and the quantum yield of non-regulated energy dissipation Y (NO) increased gradually. The nonphotochemical quantum yield due to PSI donor side limitation Y (ND) changed little, but the nonphotochemical quantum yield due to PSI acceptor side limitation Y (NA) increased gradually, resulting in the decrease of PSI actual photochemical efficiency Y (I). The irrigation of 30 mmol·L -1 acetic acid and 2% wine significantly relieved the stress of 15% seawater. The actual photochemical efficiency of PSI and PSII increased significantly, meanwhile the energy dissipated through heat decreased, then enhanced the efficiency of light energy utilization of grape leaves, in which 2% wine treatment showed a more obvious alleviated effect.【Conclusion】Irrigation of acetic acid and wine significantly improved root activity and chlorophyll content, which alleviated the photoinhibition level and improved the adaptability of grape to saline environment. The results provided a theoretical basis for the use of extract of wine lees to improvement of coastal saline soil.

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    Effect of Different Intercropping Types on the Growth of Replanted Apple Tree and Soil Environment
    MA ZiQing, DUAN YaNan, SHEN Xiang, CHEN XueSen, YIN ChengMiao, MAO ZhiQuan
    Scientia Agricultura Sinica    2018, 51 (19): 3815-3822.   DOI: 10.3864/j.issn.0578-1752.2018.19.018
    Abstract218)   HTML5)    PDF (406KB)(205)       Save
    【Objective】Taking the soil of the old apple orchard as the object, this study is to explore the effects of mixed planting of different crops and replanted young apple trees on replanting plants and soil environment, select the more effective mixed plant to reduce the apple replant disease, and to provide technical support for the renewal of old orchards.【Method】The experiment included 5 treatments, which were CK (the old apple orchard soil), T1 (the methyl bromide fumigation old apple orchard soil), T2 (grafted apple seedlings mixed with Allium fistulosum), T3 (grafted apple seedlings mixed with Triticum aestivum), T4 (grafted apple seedlings mixed with Brassica juncea). the effect of mixed planting of different crops on the aboveground biomass, soil enzymes activity, soil microbial quantity, and soil phenolic acid content was detected. The copy number of the major harmful fungi in soil of old orchard was detected by real-time quantitative PCR technology.【Result】Mixed the three kinds of crops and young apple tree obviously enhanced the young apple tree plant height, ground diameter, fresh weight, dry weight, average fresh shoot length, and total fresh shoot length, and the treatment of mixed planting with A. fistulosum (T2) had the most beneficial effect, which plant height, ground diameter, fresh weight, dry weight, average fresh shoot length, and total fresh shoot length were 1.12, 1.31, 1.71, 1.65, 1.25 and 2.09 times of the control, respectively. mixed planting three crops could increase the number of soil bacteria and reduce the number of soil fungi. Compared with the control, the number of soil bacteria increased by 37.93%, and the number of soil fungi reduced by 41.33% under the treatment of mixed planting with A. fistulosum, the number of soilbacteria increased by 31.03% under the treatment of mixed T. aestivum, the number of soil bacteriaincreased by 13.79% under the treatment of mixed B. juncea. The ratio of bacteria to fungus in the soil increased by 135.11%, 128.55% and 89.66% when mixed A. fistulosum, T. aestivum, B. juncea, respectively. Compared with the control, the gene copy number of Fusarium genus in the mixed three kinds of crops decreased, and showed significant differences. The gene copy number of F. moniliforme, F. oxysporum, f. solani and F. proliferatum declined by 61.01%, 37.11%, 40.97% and 53.11% under the treatment of mixed planting with A. fistulosum, respectively. Mixed the three kinds of crops and young apple tree could increase the activity of main soil enzymes, among which the mixed planting of B. juncea had the obvious promotion effect of urease activity compared with the control, which increased by 44.59%. the mixed planting of T. aestivum increased the activity of phosphatase and sucrose by 59.26% and 50.37%, respectively. The content of phlorzin in mixed planting A. fistulosum, T. aestivumcrops and B. juncea soil decreased by 81.23%, 20.56% and 86.11%, respectively, the total amount of phenolic acid in the soil of the mixed planting of A. fistulosum decreased by 28.27% compared with the control, and the effect was better than other treatments.【Conclusion】Mixed planting of A. fistulosum, T. aestivum and B. juncea has great influence on soil environment and biomass of replanted young trees. All of the three mixed crops can promote the growth of replanted young trees, optimize the structure of microbial community and increase the activity of main enzymes in replanted soil, decrease the content of phlorzin in soil, and reduce the apple replant disease. Among them, the effect of mixed with A. fistulosum is the best.
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    Effects of Soil Fertility on Rice Yield and Nitrogen Use Efficiency in a Red Paddy Soil
    WeiFu PENG, WeiSheng LÜ, Shan HUANG, YongJun ZENG, XiaoHua PAN, QingHua SHI
    Scientia Agricultura Sinica    2018, 51 (18): 3614-3624.   DOI: 10.3864/j.issn.0578-1752.2018.18.017
    Abstract352)   HTML17)    PDF (422KB)(205)       Save

    【Objective】 Soil fertility is the basis for high rice yield in the red paddy soil. It is critical to clarify the effects of different fertility levels on crop yield and nitrogen (N) use efficiency, thereby providing scientific evidence for soil fertility improvement and appropriate fertilizer management in red paddy soil. 【Method】 A pot experiment was carried out on red paddy soils with similar texture and different fertility levels (The level of soil organic matter represented the level of soil fertility) with the 15N isotopic tracer technique. The effects of soil fertility (FL, FM, and FH represent low, medium, and high fertility soils with a soil organic matter 19.9, 29.6, 38.9 g·kg-1, respectively) and N fertilizer rate (N0, N150, and N225 represent the N application rate at 0, 150, and 225 kg·hm-2, respectively), with 9 treatments (FLN0, FLN150, FLN225, FMN0, FMN150, FMN225, FHN0, FHN150, and FHN225) on rice yield and its composition, N uptake and its fate were investigated. 【Result】 Increasing soil fertility and N fertilization significantly increased the number of effective panicles, yield, and total N uptake of rice. Compared with N0, FL, FM, and FH increased rice yield by 63%, 40% and 17% under N150 treatment, respectively, with 89%, 55% and 23% under N225 treatment, respectively. In medium and low fertility soils, increasing the N rate significantly increased rice yield, whereas no significant difference was found between the FHN150 and FHN225 treatments. Using the 15N tracing technique, we found that the uptake of fertilizer N and soil N by rice plants increased with the increasing soil fertility under the same N application rate. However, the proportion of N derived from soil (Ndfs) increased with the increasing soil fertility, while the proportion of N derived from fertilizer (Ndff) showed the opposite trend. Increasing N fertilization rate led to an increase in Ndff, while reducing Ndfs. The average N recovery efficiency (NRE) of FL, FM, and FH was 42%, 48% and 52%, respectively; with the average N fertilizer residue rate of 20%, 23% and 28%, and the average N fertilizer loss rate of 38%, 29% and 20%, respectively. The NRE of FLN225 was significantly higher than FLN150 with no significant difference with FM soils, while the NRE of FHN225 was significantly lower than FHN150. Increasing soil fertility significantly increased the contents of soil microbial biomass N, ammonium N, and fixed ammonium. 【Conclusion】 These results indicated that the higher of the soil fertility, the higher of the rice yield, the NRE and the N residual rate in the red paddy soil were, and the lower of the N loss rate was. Therefore, increasing N application rate was effective to increase both rice yield and NRE in low fertility soils. In contrast, an appropriate reduction in N application rate might benefit rice NRE and reduce fertilizer N losses without compromising rice yield.

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