Loading...

Table of Content

    16 November 2017, Volume 50 Issue 22
    CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    Changes of Micro-Structural Characteristics of Starch Granules and the Mechanisms Under Different Phosphorus Application Rates in Wheat (Triticum aestivum L.)
    ZHANG RunQi, FU KaiYong, LI Chao, ZU SaiChao, LI ChunYan, LI Cheng
    Scientia Agricultura Sinica. 2017, 50(22):  4235-4246.  doi:10.3864/j.issn.0578-1752.2017.22.001
    Abstract ( 307 )   HTML ( 5 )   PDF (1711KB) ( 308 )   Save
    References | Related Articles | Metrics
    【Objective】 Phosphorus is one of the three essential nutrients for crops. Pores and channels in starch granules play an important role in starch biosynthesis and physicochemical characteristics of wheat (Triticum aestivum L.). This study was conducted to reveal the changes of micro-structural characteristics of starch granules and the mechanisms under different phosphorus application rates in wheat. It may provide more information to improve the pathway of starch biosynthesis. 【Method】 The wheat cultivar Xindong 23 was used in this study. On 160 d after sowing (about 5% plants returning green), three levels of phosphorus treatments, i.e., control (CK, P2O5, 0 kg·hm-2), conventional phosphorus (CP, P2O5, 105 kg·hm-2) and high phosphorus (HP, P2O5, 210 kg·hm-2), were applied, and the samples were collected on the 7, 14, 21, 28 and 35 days post anthesis (DPA). The micro-structural morphology of mature starch granules and the morphological changes of starch granules digested by endogenous (germination) and exogenous (amyloglucosidase) enzymes were examined using scanning electron microscopy. The concentration of reducing sugars after amyloglucosidase digestion of starches was studied, and the channel structure within starch granules was observed using confocal laser scanning microscopy. The expression patterns of the genes involved in starch biosynthesis and degradation were investigated using real-time qPCR and in situ hybridization.【Result】The shape of the starch granules in different phosphorus treatments did not show a significant difference. However, in response to CP treatment, the “pinholes” on the granules were easier to find, and the fluorescence from the starch granules was stronger and clearly visible. At 6 days post germination (DPG), the number of “pinholes” and pits on the starch granules in CP treatment was most abundant. After exogenous amyloglucosidase digestion, the A-type starch granules developed under CP or HP conditions were more prone to be broken into halves than those formed under CK conditions; the concentration of reducing sugars was also higher after amyloglucosidase digestion of the starch granules developed under CP or HP conditions. These data suggest dissimilar micro-structural changes of starch granules induced by different phosphorus application rates. Under conventional phosphorus application rate, the expression levels of the genes involved in starch biosynthesis and degradation were significantly higher than those under the control and high phosphorus conditions during wheat grain filling. In addition, phosphorus application promoted the transcripts of amy4, bam1 and bam5 genes accumulated in the peripheral cells of the endosperm, and this effect was more pronounced in CP treatment. 【Conclusion】 Different phosphorus application rates did not significantly affect the shape of starch granules, but the micro-pores and channels in the starch granules and the relative expression levels of the genes involved in starch biosynthesis and degradation were significantly increased by CP application. Furthermore, CP treatment increased the transcript levels of amy4, bam1 and bam5 in the peripheral cells of the endosperm. These transcriptional changes may alter the balance between starch synthase and hydrolase activities, which may have an impact on the micro-structural characteristics of starch granules.
    Screening for French Fries Processing Potato Lines According to Colour Qualities and Properties
    LIU Juan, LIANG YanChao, YU Bin, LI Cheng, WANG YuPing, CHENG LiXiang, ZHANG Feng
    Scientia Agricultura Sinica. 2017, 50(22):  4247-4265.  doi:10.3864/j.issn.0578-1752.2017.22.002
    Abstract ( 296 )   HTML ( 9 )   PDF (2027KB) ( 307 )   Save
    References | Related Articles | Metrics
    【Objective】 French fries are the main important potato processing products. The compositions of potato tuber are effected by storage environments after harvest. The change of the tuber compositions affects the features of physio-chemical characteristics of in tubers resulted in potato processing colour and texture. The French fry quality of potato should be analyzed and classified according to the commercially processing criteria. Firstly, screening of French fries processing potato lines according to agronomic traits in fields. Then, analyzing potato tuber processing colour and texture qualities from varieties and advanced lines according to current consumption habits and market demand. The above standards are important required for French fry varieties screening purpose. 【Method】Selection at an early breeding stage, characteristics with agronomic traits such as yield, tuber size, tuber shape, tuber colour, eye depth, tuber length, tuber width, ratio of tuber length to width, diseases resistance and commodity rate were evaluated based on three different locations in three years. Fourteen potato varieties and lines were selected for French fry qualities test after storage for 0, 60, and 120 days at 4℃ and 25℃, respectively. The contents of dry matter, starch, total glycoalkaloid, sucrose, reducing sugars, free amino acids, chlorogenic acid, ascorbic acid, citric acid were measured. In addition, the French fry colour change, the tuber and French fry hardness were determined and analyzed. A correlation analysis was conducted to determine the correlation coefficient between the content of starch and the hardness. 【Result】In regard to tuber shape, the processing standard for French fry is long to long-oval. A longaxis to transverse-axis ratio greater than 1.5:1 is acceptable. The ratios refer to variety characteristics as a mean value, not to natural variations in shape which may occur within a variety. Tubers should be uniform and not excessively disfigured by secondary growth, enfolded ends or growth cracks. The values of ΔE reflected the change of French fry colour under different storage environments. The correlation analysis indicated that the changes of colour were caused mainly by fructose, glucose, and secondly by chlorogenic acid. The content of ascorbic acid was correlated only with brightness colour parameter, L value. The content of fructose, glucose, sucrose, chlorogenic acid had a positive significant correlation with a and b values. There was a positive correlation between hardness and tuber starch content in fresh tuber and French fry. The decrease of hardness was caused mainly by the water loss and starch degradation. 【Conclusion】The present results indicated that after field agronomic traits screening, colour and texture evaluation under different storage environments, the varieties Russet Burbank, Shepody and lines 0719-32, 0716-39 are the better French fry processing potato varieties and lines.
    Molecular Cloning, Expression Analysis and Development of Functional Markers for SiARGOS1 Gene in Foxtail Millet
    WANG ZhiLan, DU XiaoFen, WANG Jun, YANG HuiQing, WANG XingChun, GUO ErHu, WANG YuWen, YUAN Feng, TIAN Gang, LIU Xin, WANG QiuLan, LI HuiXia, ZHANG LinYi, PENG ShuZhong
    Scientia Agricultura Sinica. 2017, 50(22):  4266-4276.  doi:10.3864/j.issn.0578-1752.2017.22.003
    Abstract ( 207 )   HTML ( 6 )   PDF (3126KB) ( 283 )   Save
    References | Related Articles | Metrics
    【Objective】The homologous genes of Arabidopsis ARGOS (auxin-regulated gene involved in organ size) family were isolated from foxtail millet, which were induced expression by hormone and participate in the regulation of plant organ size. Bioinformatics, including alignment of amino acid sequences and promoter cis acting elements, and the expression pattern in different tissues and plant hormones were analyzed. Functional markers were developed from sequences analysis of gene encoding region and promoter, which will play an important role in genetic improvement of yield traits, accelerate breeding process and increase yield of foxtail millet.【Method】The number of ARGOS family members and the sequence of the ARGOS family in foxtail millet were analyzed through BLAST of conserved domain with the existing ARGOS in other plants. The encoding region and promoter sequences of SiARGOS1 gene, one of the family members of ARGOSin foxtail millet, were obtained with homologous cloning method. The promoter cis acting elements of SiARGOS1 was analyzed by the bioinformatics analysis. Expression patterns in different tissues and plant hormone of SiARGOS1 were analyzed using real-time PCR. Functional markers were developed from sequence analysis of SNP and insertion/deletion in gene encoding region and promoter. Functional markers of elite alleles of yield related traits were tested using data analysis of significant differences between genotypes associated with the yield traits such as panicle weight, grain weight and thousand-grain weight in 85 cultivars. 【Result】A total of six ARGOS family members were found to have a conserved OSR (Organ Size Related) domain consisting of two transmembrane helical structures and a highly conserved proline-rich motif in foxtail millet. the open reading frame (ORF) and the promoter of SiARGOS1, one of the family members homologous to Arabidopsis AtARGOS were cloned. Sequence analysis showed that the ORF of SiARGOS1 on chromosome 8 encoding a putative protein composed of 113 amino acids was 342 bp in length, without intron. The promoter contains a variety of regulation related components including auxin, ethylene and other plant hormone with 2 109 bp in length. SiARGOS1 is expressed in all organs of foxtail millet, at high levels in root, whereas at lowest level in panicle. The gene was insensitive to indole-3-acetic acid (IAA), but was up-regulated by ethephon (ETH). On the basis of the alignment of gene SiARGOS1 genomic DNA sequence, CAPS-AccⅡmarker was developed on the missense polymorphism site (C/G→Ala/Gly) at the 150 bp of the encoding region, two SSR markers, AP-1 and AP-2, were developed at -1652--1651(TA)2/3 and -1165--1163(TCA)1/2 of promoter, respectively. No significant association was found among the yield associated traits such as panicle weight, grain weight and thousand-grain weight with CAPS-AccⅡ and AP-1 in 85 cultivars. However, AP-2 proved to be highly correlated with panicle weight and grain weight in 85 cultivars, in addition to thousand-grain weight. The average values of panicle weight for two genotypes were 15.52 g and 20.61 g, respectively, while the ones of grain weight for two genotypes were 12.24 g and 16.74 g, respectively. 【Conclusion】Six ARGOS family members were found in foxtail millet , all of which had conserved OSR domain. The open reading frame (ORF) of SiARGOS1, homologous to Arabidopsis thaliana AtARGOS, is 342 bp in length without intron. The SSR marker AP-2, which was developed in the promoter region of thegene, could be used as functional marker for the selection of superior allelic variation in yield traits such as panicle weight and panicle weight of foxtail millet varieties.
    TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    Root Growth Responses to Soil Water Deficit for a Water-Saving and Drought-Resistant Rice Genotype Hanyou113
    BU HongYing, SONG WeiZhou, CAO CouGui, LI Ping
    Scientia Agricultura Sinica. 2017, 50(22):  4277-4289.  doi:10.3864/j.issn.0578-1752.2017.22.004
    Abstract ( 213 )   HTML ( 3 )   PDF (668KB) ( 344 )   Save
    References | Related Articles | Metrics
    【Objective】 The objective of this paper is to reveal root morphological and physiological changing characteristics of water-saving and drought-resistant rice under soil water deficit condition, and to illuminate its specific physiological basis of water-saving and drought-resistance. 【Method】 Pot experiments were conducted in 2015 and 2016, and one water-saving and drought-resistant rice genotype (HY113) and one high-yielding rice genotype (YLY6) were used under two water treatments, including flooding irrigation and drought treatment. The drought effects on root morphological and physiological traits of the two rice genotypes and their relationship with aboveground biomass accumulation were studied.【Result】Compared with flooding irrigation, drought stress significantly reduced the dry matter accumulation of the two rice genotypes, and the root-shoot ratio of HY113 was also decreased significantly (from 0.18 to 0.12), while the root-shoot ratio of YLY6 was not changed. Under drought stress, the root activity of the two rice genotypes both increased significantly. In 2015 and 2016, the average increase percentage of HY113 was 38.7% at milky stage, while that of YLY6 was 22.8%, and the root activity of HY113 increased from 86 μg·g-1·h-1 to 174 μg·g-1·h-1at milky stage in 2015. Drought treatment also significantly reduced the root absorption area of both two genotypes, but the reduction percentage of HY113 was significantly lower than that of YLY6. Compared with high-yielding rice YLY6, HY113 had smaller root number, root volume and root dry weight, and the total dry matter accumulation was also significantly lower, but its root activity and root absorption area were greater. 【Conclusion】The water-saving and drought-tolerant rice genotype HY113 possesses less root biomass but higher root uptake efficiency, and it could reduce the root-shoot ratio under drought condition to make more dry matter stay in the aboveground part, so that the relatively high grain yield could be maintained.
    Review of Light and Simplified Cotton Cultivation Technology in the Yellow River Valley
    DONG JianJun, DAI JianLong, LI Xia1, LI WeiJiang, DONG HeZhong
    Scientia Agricultura Sinica. 2017, 50(22):  4290-4298.  doi:10.3864/j.issn.0578-1752.2017.22.005
    Abstract ( 233 )   HTML ( 6 )   PDF (371KB) ( 418 )   Save
    References | Related Articles | Metrics
    The cotton-growing region of Yellow River valley is one of the three major cotton producing areas in China. It is of great strategic significance to promote the sustainable development of cotton production in this area through full improvement of cultivation technology. Firstly, the main problems of current cotton cultivation and management technology in the cotton area of the Yellow River valley were analyzed in the paper. These problems mainly include the diversification of cotton planting system and planting pattern, which hinders the simplification and mechanization in cotton production; the scale of cotton production is small with poor organization; the field management of cotton is not only complicated, but also cumbersome and labor-intensive due to poor mechanization. It is also indicated that a large number of rural labors have been transferred to the city due to the fast urbanization in this area, which leads to the decrease in both the number and quality of rural labors, making it difficult to support the traditional labor-intensive cultivation of cotton. Thus many problems occurred in cotton production such as great consumption of labors, large material input and low economic benefits, which are the main obstacles to the sustainable development of cotton production in this area. Adoption of light and simplified cultivation technology is an important way to improve the Chinese cotton competitiveness in the world market and the sustainable development of cotton production in the Yellow River valley of China. Secondly, the formation and development process of light and simplified cotton cultivation technology were reviewed. The key techniques for light and simplified cotton cultivation, including precision seeding, simplified seedling nursing and transplanting, concentrated fruiting, easy and simplified pruning and fertilization, water-saving irrigation and other light cultivation techniques for cotton production were summarized and reviewed. Finally, based on the review, the authors proposed tentative ideas to simplify management, save costs and improve fiber quality and economic benefits by further improvement and development of the light and simplified cotton cultivation technology. In order to achieve a higher level of light and simplified cultivation in the future, more attention should be paid to seeding and harvesting as well as to simplifying and reducing the management process. The planting system and planting mode should be further optimized to lay a foundation for the implementation of mechanized production; the precision sowing technology should be further improved to ensure full stand establishment after seeding once; new fertilizers and their application technology should be continually developed to further simplify fertilization and improve fertilizer use efficiency; cotton varieties suitable for light cultivation and mechanized harvest should be genetically developed to enhance mechanized harvesting of cotton according to local conditions. While continuing to innovate the key cultivation technologies, the integration of agricultural machinery and agronomic measures as well as the combination of the fine variety with fine cultivation method must also be strengthened. It is foreseeable that in the near future, the light and simplified cotton cultivation technology system will be further improved, which will play more important roles in sustainable development of cotton production in this area.
    Effects of Heterogeneous Root Zone Salinity on Plant Growth and Ion Characteristic in Alfalfa
    SUN JuanJuan, YU LinQing, ZHAO JinMei, LIU HongLin, ZHANG YingJun
    Scientia Agricultura Sinica. 2017, 50(22):  4299-4306.  doi:10.3864/j.issn.0578-1752.2017.22.006
    Abstract ( 190 )   HTML ( 3 )   PDF (347KB) ( 250 )   Save
    References | Related Articles | Metrics
    【Objective】Soil salinity is spatially heterogeneous. The effects of heterogeneous salinity on the growth, water uptake, photosynthetic parameter, K+ and Na+ concentration in leaf and root of alfalfa plants were determined to improve understanding of non-uniform salt stress tolerance mechanisms of alfalfa, so as to provide theoretical evidence for breeding the new alfalfa varieties tolerant to salt, and to improve alfalfa plant in salinity areas. 【Method】 Plant growth, water uptake, tissue ionic concentrations were studied in alfalfa plants grown hydroponically for 7 days using a split-root system, with uniform 0 and 200 mmol·L-1 NaCl or heterogeneous 0/400 and 100/300 mmol·L-1 NaCl. 【Result】 Neither uniform salinity or heterogeneous salinity inhibited alfalfa growth, decreased water uptake, increased leaf Na+ concentration and decreased leaf K+ concentration. Compared with uniform 200 mmol·L-1 NaCl, 0/400 treatment significantly increased the alfalfa shoot fresh weight and whole plant water uptake. Shoot fresh weight and whole plant water uptake under 0/400 treatment were 24.3% and 44.2%, respectively, higher than 200/200 treatment. The leaf Na+ concentration in 0/400 treatment was 53.6% lower than in 200/200 treatment, and the leaf K+ concentration was similar with 200/200 treatment . But water uptake in non-salinity root was 12.3% higher and Na+ concentration in non-salinity root of 0/400 treatment was 10.5-fold higher than control, whereas K+ concentration in non-salinity root of 0/400 treatment was similar with control. There were no significantly differences of shoot fresh, water uptake and leaf K+ concentration between 100/300 and 200/200 treatment, but leaf Na+ concentration in 100/300 treatment were 31.0% higher than in 200/200 treatment. Water uptake were 33.9% lower, K+ concentration was 31.3% lower, and Na+ concentration were 39.5-fold in low-salinity root of 100/300 treatment, compared with control. Transpiration rate, stomatal conductance and intercellular CO2 concentration of 0/400, 100/300 and 200/200 treatment were similar with each other and significantly lower than control, however, net photosynthetic of 0/400 and 200/200 were significantly higher than control, and net photosynthetic of 100/300 were similar with control.【Conclusion】When root average salinity was 200 mmol·L-1 NaCl, the NaCl concentration of high salinity root were equal or greater than half lethal concentration, heterogeneous salinity can improve alfalfa plant growth when low salinity root under 0 mmol·L-1 NaCl, but heterogeneous salinity can not improve alfalfa plant growth when low salinity root under 100 mmol·L-1 NaCl.
    PLANT PROTECTION
    Effects of Cyantraniliprole on Development, Fecundity and Nutritional Utilization of Athetis dissimilis
    DING JinFeng, XU ChunMei, ZHANG ZhengQun, ZHAO YunHe, LIU Feng, MU Wei
    Scientia Agricultura Sinica. 2017, 50(22):  4307-4315.  doi:10.3864/j.issn.0578-1752.2017.22.007
    Abstract ( 216 )   HTML ( 2 )   PDF (432KB) ( 235 )   Save
    References | Related Articles | Metrics
    【Objective】In order to clarify the control effect of cyantraniliprole on Athetis dissimilis, the effects of cyantraniliprole at low-lethal dosages on the growth, reproduction and nutritional utilization were studied after treated the 4th instar larvae of A. dissimilis. 【Method】The toxicity, as well as the nutritional utilization and the content of biochemical substances of cyantraniliprole on the 4th instar larvae of A. dissimilis were determined by using the method of artificial diet mixed with insecticides. The sublethal effects of cyantraniliprole on growth and development index: developmental time of larvae and pupae, mean longevity of adults, fecundity of females, the rate of pupation and eclosion were investigated. The feeding indices, such as the approximate digestibility (AD), the relative consumption rate (RCR), the relative growth rate (RGR), the efficiency of conversion of ingested food (ECI), and the efficiency of conversion of digested food (ECD) were determined at 72 h after treatment with different dosages of cyantraniliprole, and the contents of nutrients such as carbohydrates, proteins and lipids were also analyzed at 24, 48 and 72 h after cyantraniliprole treatment. 【Result】The result of bioassay showed that cyantraniliprole had high toxicity against 4th instar larvae of A. dissimilis, the LC50 value was 0.66 µg·g-1 artificial diet. The concentrations that caused 5% and 25% mortalities were 0.13 and 0.34 µg·g-1 artificial diet, respectively. After being treated with cyantraniliprole, the durations of the 4th instar to 6th instar larvae stage were significantly prolonged 1.63, 1.75 and 5.48 days in the LC5, LC25 and LC50 treatments, respectively. The period of pupae was prolonged while the period of adults was shortened, the pupation and eclosion rate were also declined. In addition, the pupal weight of female A. dissimilis in LC5 (130.2 mg), LC25 (127.8 mg) and LC50 (127.5 mg) treatment groups was significantly reduced compared with the control group (146.7 mg). However, there was no significant difference in the pupal weight of male. The fecundity of female adults was also greatly decreased after treated with sublethal concentrations of cyantraniliprole, with 755.1, 558.8, 506.9 and 462.8 eggs/female, in the control, LC5, LC25, and LC50 group, respectively. Meanwhile, the oviposition period was also significantly shortened, but cyantraniliprole did not have significant effect on the adult preoviposition period. compared with the control group, cyantraniliprole had markedly antifeedant effects, which significantly decreased the RGR, RCR, ECI and ECD of larvae. The amount of total carbohydrate in the 4th instar larvae of A. dissimilis in cyantraniliprole-treated groups decreased significantly compared with the control group in 24 h, similarly, from 48 h to 72 h. Meanwhile, the effects on the contents of proteins and lipids in the treatment groups were similar to carbohydrates. All these adversely affected the normal growth and development of A. dissimilis. 【Conclusion】Low-lethal dosages of cyantraniliprole can suppress the development and fecundity of A. dissimilis population, which is beneficial to the long-term control of A. dissimilis.
    Polyclonal Antibody Preparation of Spodoptera exigua Vitellogenin and Its Protein Expression at Different Developmental Stages
    ZHAO Jing, SUN Yang, TAN YongAn, XIAO LiuBin, JIANG YiPing, BAI LiXin
    Scientia Agricultura Sinica. 2017, 50(22):  4316-4324.  doi:10.3864/j.issn.0578-1752.2017.22.008
    Abstract ( 198 )   HTML ( 2 )   PDF (1452KB) ( 467 )   Save
    References | Related Articles | Metrics
    【Objective】 The objective of this study is to prepare the polyclonal antibody of Spodoptera exigua vitellogenin (Vg), investigate the expression pattern of Vg protein in female hemolymph of S. exigua at different developmental stages, and to provide a basis for studying the function and mechanism of synthesis, transportation and utilization.【Method】The fragment of Vg was amplified from the cDNA of 24-h-old female adults of S. exigua by PCR which included the vitellogenin-N region. The fragment of Vg was then inserted into the pMD-19T for sequencing. The nucleic acid sequence and the amino acids encoded by this gene fragment were analyzed by DNAMAN software. The sequenced Vg fragment was inserted into the expression vector pCzn1 by Nde I and Xba I digestion. The recombinant vector pCzn1-Vg was then inserted into Escherichia coli ArcticExpress. The E. coli ArcticExpress expressing the Vg recombinant protein was collected and crushed by ultrasonic. The supernatant and the precipitate were collected, respectively, and SDS-PAGE was used to analyze the expression of the recombinant protein. The recombinant Vg protein was expressed at different temperatures and concentrations of IPTG and the optimized expression condition was achieved. The recombinant protein was purified by Ni-NTA agarose. The purified recombinant protein was used to produce polyclonal antibody via immunizing rabbit. The titer of rabbit anti-Vg antiserum was evaluated by indirect ELISA. The content of Vg in female hemolymph of S. exigua at different developmental stages was detected by Western blot. 【Result】 The length of the fragment of Vg is 2 091 bp, encoding 697 amino acids. The predicted molecular weight of Vg recombinant protein is 80.88 kD. The molecular weight of Vg recombinant protein expressed in E. coli is 80 kD, which is consistent with the predicted molecular weight. It was mainly expressed in inclusion body rather than the supernatant. The results of Vg recombinant protein content expressed at different temperatures and concentrations of IPTG showed that it was highly expressed at inducing temperature of 25℃ with 0.6 mmol·L-1 IPTG. It had no obvious effect on boosting the Vg recombinant protein level and other protein content increased by raising temperature and the concentration of IPTG. After immunizing New Zealand white rabbits with four times, the ELISA assay showed that the rabbit anti-Vg antiserum had a good sensitivity with the titer 1﹕512 000. The Vg content in female hemolymph of S. exigua at different developmental stages was detected by Western blot. A single Vg band of approximately 180 kD was detected. Vg was first expressed at late stage of female pupa and showed a low expression level. After female adult eclosion, Vg expression was in a dynamic balance which peaked in 48-h-old female adults, then decreased. 【Conclusion】 The Vg recombinant protein was successfully purified and the optimized expression condition (temperature of 25℃ with 0.6 mmol·L-1 IPTG) is clearly defined. The polyclonal antibody of Vg protein with high titer was obtained and the expression pattern of Vg in S. exigua is explicit.
    SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT
    Hyperspectral Features and Wavelength Variables Selection Methods of Soil Organic Matter
    ZHU YaXing, YU Lei, HONG YongSheng, ZHANG Tao, ZHU Qiang, LI SiDi, GUO Li, LIU JiaSheng
    Scientia Agricultura Sinica. 2017, 50(22):  4325-4337.  doi:10.3864/j.issn.0578-1752.2017.22.009
    Abstract ( 219 )   HTML ( 3 )   PDF (809KB) ( 280 )   Save
    References | Related Articles | Metrics
    【Objective】The objective of this study is to explore the hyperspectral features and response regularity of the soil organic matter, and to select the sensitive wavelengths of soil organic matter, so as to reduce complexity of hyperspectral estimation model of soil organic matter and improve robustness of the model, which is to provide theoretical support to quantitatively monitor the soil fertility of farmland by using the hyperspectral technology. 【Method】 A total of 130 fluvo-aquic soil samples were collected from Jianghan plain, of which 40 were the training set samples. The soil organic matter content (SOMCraw) and spectral reflectance (SRraw) were measured from total samples, and an experiment of removal of organic matter was performed using the training set samples, and then we measured the soil organic matter content (SOMCrem) and spectral reflectance (SRrem) from samples of removal of organic matter. By calculating the difference and rate of change between SRraw and SRrem from training set samples, we could analyze how the content changes of soil organic matter itself influence the spectral features. The soil organic matter sensitive wavelengths were determined by the methods of uninformative variables elimination (UVE) and competitive adaptive reweighted sampling (CARS). The calibration set with 45 samples was utilized to build the soil organic matter estimation models base on partial least squares regression (PLSR) and back propagation neural network (BPNN), and the validation set of 45 samples was utilized to test whether sensitive wavelengths were suitable for the same type soil. 【Result】 The experiment of removal of organic matter showed that the average spectral reflectance of test soil samples increased at full-spectrum with removing organic matter content, especially at the visible spectrum; after the comparison of UVE, CARS, UVE-CARS, and CARS-UVE, the optimal method of variables selection was UVE-CARS. The method of UVE-CARS provided 84 selected variables which were the soil organic matter sensitive wavelengths with coverage area of 561-721, 1 920-2 280 nm. Based on soil organic matter sensitive wavelengths, the PLSR and BPNN had better performance than full-spectrum model, and BPNN was better than PLSR in predictive ability with its value of R2, RMSE, RPD, MAE, MRE were 0.74, 1.33 g·kg-1, 2.02, 1.04 g·kg-1, 6.2%, respectively, so it could effectively estimate soil organic matter. 【Conclusion】 The soil organic matter sensitive wavelengths from training set could effectively estimate soil organic matter content in this test area with the same type samples. In addition, modeling of sensitive wavelengths by obtaining from the experiment of removal of organic matter and variables selection method could not only compress input wavelengths down into 4.2% of full-spectrum, but also enhance the estimation accuracy and reduce the model complexity. In this study, it provided a new approach to quickly and accurately evaluate soil organic matter content in the farmland.
    Variation of Winter Wheat Grain Zinc Concentration and Its Relation to Major Soil Characteristics in Drylands of the Loess Plateau
    SHE Xu, WANG ZhaoHui, MA XiaoLong, CAO HanBing, HE HongXia, WANG Sen
    Scientia Agricultura Sinica. 2017, 50(22):  4338-4349.  doi:10.3864/j.issn.0578-1752.2017.22.010
    Abstract ( 241 )   HTML ( 8 )   PDF (440KB) ( 186 )   Save
    References | Related Articles | Metrics
    【Objective】 In dryland of the Loess Plateau, winter wheat grain zinc (Zn) concentration is usually very low in most areas, but it still varied a lot among different locations or fields. Clarification of the causes of grain Zn variation is essential for improving wheat Zn nutrition and grain Zn biofortification. 【Method】 During 2014-2015 and 2015-2016, both soil and wheat grain samples were collected from 379 randomly selected rain-fed fields of Shanxi, Shaanxi, and Gansu provinces, where wheat is widely planted. Pearson correlation was used to investigate the relationships between wheat grain Zn concentration and the selected soil characteristics. 【Result】 The wheat grain Zn concentration ranged from 12.2 mg·kg-1 to 50.7 mg·kg-1 among different fields. The Pearson correlation analyses showed that, grain Zn concentration was significantly and negatively correlated with soil moisture, available Fe in all 0-100 cm layers, soil pH, available P in most soil layers, and available Mn and Cu in top soil layers. While wheat grain Zn concentration was significantly and positively correlated with soil nitrate, available K, and available Zn in 0-20 cm layer. Moreover, grain Zn was found no correlation with soil organic matter, total N in 0-100 cm layers, and ammonium in most soil layers. At maturity, 0-100 cm soil moisture in the fields of high Zn groups (mean = 39.2 mg·kg-1) was 8.2%, and 23% lower than that in the fields of low Zn groups; 0-20 cm soil pH in the fields of high Zn groups was 8.3, and 1.4% lower than that of low Zn groups; and soil available P, available Fe, available Mn, and available Cu of high Zn groups were 12.1, 3.2, 10.6, and 1.0 mg·kg-1, and 21%, 37%, 6%, and 33% lower than that in low Zn groups, respectively. However, soil nitrate, available K, and available Zn of high Zn groups were 23, 150, and 0.54 mg·kg-1, which were 246%, 27%, and 35% higher than that of low Zn groups, respectively. 【Conclusion】 Large wheat grain zinc variation was found among different areas and fields of the Loess Plateau, and it was mainly affected by soil characteristics including moisture, pH, nitrate, available P, available K, and available Fe, Mn, Cu and Zn, in which moisture and available Fe were more important. Optimizing agronomic water and nutrient management to increase soil water, N, K, and Zn supply capacity, and to some extent to decrease soil available P, and available Fe Mn and Cu without yield loss, should be potential measures for biofortification of wheat grain Zn on the Loess Plateau.
    Purification and Identification of the Biosurfactant Produced by Enterobacter Hormaechei B4 and Its Application
    WANG Quan, WANG JiaYin, ZHU Han, ZHUO JinYu, LIU DongYang, SHEN QiRong
    Scientia Agricultura Sinica. 2017, 50(22):  4350-4361.  doi:10.3864/j.issn.0578-1752.2017.22.011
    Abstract ( 255 )   HTML ( 3 )   PDF (2012KB) ( 168 )   Save
    References | Related Articles | Metrics
    【Objective】 The objective of this study is to optimize the biosurfacants produced by Enterobacter hormaechei B4, to purify the biosurfacants through organic reagent extraction and high performance liquid chromatography, to identify the biosurfacants by HPLC-MS, and to evaluate the efficiency of improving foliar fertilizer absorption, which will provide theoretical basis for the development of new fertilizers. 【Method】 The optimization of biosurfacants production by Enterobacter hormaechei B4 was carried out by orthogonal experiment, and the major parameters were used in this study, including the carbon resources, nitrogen resources, initial pH, temperature, inoculum amount, revolutions, and incubation time. The evaluation index of different treatments was the surface tension value of the fermented liquid, and the treatment with the lowest surface tension was the optimum experimental group. The crude biosurfacants were extracted by extracted by organic regents and then concentrated by using vacuum rotary evaporation apparatus with water bath at 60 centigrade. Different functional groups contained in the purified biosurfacants were analyzed by Fourier infrared spectrum, which could provide favorable information for analyzing the structure. The purification of the biosurfacants was performed by liquid chromatography methods, and the HPLC conditions are: column temperature of 110 oC, sample size with 20 μL, flow rate of 0.5 mL·min-1. The identification of the purified biosurfacants was carried out by HPLC-MS, and the condition was as following: flow rate of 10 μL·min-1, the velocity of capillary voltage of 3.88 kV, cone voltage of 53V, ionization temperature of 100 oC, dissolution temperature of 150 oC, under the condition of using full scan mode in the center of mass, and the full scan under centroid model was used to collect the mass spectrometry data, and the biosurfactant structure was identified based on existing mass spectrometric data. In the end, the purified biosurfactant was used to evaluate the efficiency of improving foliar fertilizer absorption by cucumber through hydroponic culture and pot experiments.【Result】The results indicated that the optimum condition for biosurfactant production is listed as follow: 4% (v/v) glycerol, 3 g·L-1 sodium nitrate, initial pH 6.0, inoculum of 6%, 35 oC, 200 rpm and 96 h, under which the surface tension value of the fermented liquid decreases to 44.10 mN·m-1 and the production of the crude biosurfacants was 12.14 g·L-1. Meanwhile, the crude biosurfacants extracts could decrease the surface tension value of pure water to 44.10 mN·m-1, and this condition is considered as the optimum fermentation condition. The liquid phase separation results indicate that the crude biosurfacants extracted by organic reagent have typical characteristic peaks at 1.62-2.33 min, which also showed that it is the main component in the crude extract of the biosurfactant, and it also could decrease the surface tension value to 47.00 mN·m-1 at the concentration of 0.10 g·L-1. The FRIR analysis results indicate that the purified biosurfacants contain various functional groups including -CH2、-CO and C-O, and it is considered as biosurfacants with carbon chains. The HPLC-MS analysis results show that m/z 701.54 is [M+Na]+, and m/z 723.74 was [M-H+2Na]+, and the biosurfactant is identified as rhamnolipid, and its structure is Rha-Rha-C10-C12. By comparing to the CK (Water) and AA (Amino acids) treatments, the plant height in AAB (Amino acids and biosurfacants) increased by 79.59% and 32.9% and fresh weight increased by 43.03% and 23.98%, respectively. The chlorophyll contents  in AAB increase by 11.72% and 10.69%, respectively, by comparing to the CK and AA, in the pot experiment.【Conclusion】In brief, the condition for the biosurfacants production secreted by Enterobacter hormaeche is optimized, under which the production of the crude biosurfacants is 12.14 g·L-1, and the main component of the biosurfacants produced by Enterobacter hormaeche is identified as rhamnolipid (Rha-Rha-C10-C12), which can enhance foliar penetration and will have a good application prospect.
    HORTICULTURE
    Comprehensive Evaluation and Phenotypic Diversity Analysis of Germplasm Resources in Mandarin
    SUN ZhenZhu, LI QiuYue, WANG XiaoKe, ZHAO WanTong, XUE Yang, FENG JinYing, LIU XiaoFeng, LIU MengYu, JIANG Dong
    Scientia Agricultura Sinica. 2017, 50(22):  4362-4372.  doi:10.3864/j.issn.0578-1752.2017.22.012
    Abstract ( 364 )   HTML ( 25 )   PDF (1506KB) ( 510 )   Save
    References | Related Articles | Metrics
    Objective The objective of this study is to evaluate some major phenotypic characteristics diversity of mandarin germplasms and explore the comprehensive method for screening important mandarin germplasm resources. Method The diversity evaluation of 18 phenotypic traits in 239 mandarin accessions were carried out. Variation coefficients, Shannon-Weaver Information index cluster analysis, principal component analysis, correlation and regression analysis were comprehensively used to evaluate the relationship of characteristics and select important characteristics. Result Based on the variation coefficient of 239 mandarins, large variations were found in the traits of seed numbers per fruit (SNF), the ratio of soluble solids to titratable acidity (TSS/TA), the contents of titratable acid (TA), fruit weight (FW), while genetic characteristics of fruit shape index(FSI), segment numbers per fruit (SNPF), the contents of total soluble solids (TSS) kept relatively stable. Shannon-Weaver Information index showed that the diversity level of FW, fruit diameter (FD), fruit length (FL), SNPF, petiole length (PL), leaf lamina length (LLL), leaf lamina width (LLW), the contents of reducing sugar (RS) and invert sugar (IS) were high, while fruit surface texture(FST), SNF, TSS/TA had low diversity level. The variance analysis was conducted to evaluate the trait difference of 239 mandarin accessions, which divided into five different geographical origins. The result showed that mandarin accessions from America have higher average contents of TSS and IS; the mandarin accessions from Japan have larger FW, FD and FL and lower SNF. Mandarin accessions from the Yangtze River Basin were larger fruit size, higher contents of the TSS, RS and IS than the Pearl River Basin, but lower TSS/TA. Variance analysis for wild germplasms, landraces and bred varieties showed that bred accessions have larger fruits, smoother peels, fewer seeds, lower contents of TA and higher contents of sugar content. Both the cluster analysis and PCA suggested genetic variations were presented in different geographical origins. Small fruit type accession from China should be thought as an unique subgroup, Green Peel Mi Ju is an unique citrus accession. Principal component analysis showed that the variation cumulative contribution rate of the first nine principal components was accounted for 81.94%. The average F value from the comprehensive evaluation of phenotypic traits of 239 mandarins was 0.480. The highest F value (0.664) was given to Ehime Kashi No.21 from Japan. The lowest F value (0.211) was Shikuwasha. The correlation analysis between the phenotypic traits and F value showed that the phenotypic traits except FST were significantly correlated with the F value. Nine phenotypic traits, including fruit length (FL), FSI, FST, SNPF, PL, LLW, the contents of TSS, TA and RS, were selected out as evaluation indexes by stepwise regression analysis. Conclusion Mandarin accessions presented large phenotypic diversity. The traits difference of the accessions from different geographical origins or germplasm types are great. Nine phenotypic traits could be used as important evaluation charaterisitics for screening unique mandarin.
    Effects of Selenium on Melatonin Content and Glutathione Redox Cycle in Sweet Cherry Leaves
    SUN XiePing, LUO YouJin, ZHOU GuangWen
    Scientia Agricultura Sinica. 2017, 50(22):  4373-4381.  doi:10.3864/j.issn.0578-1752.2017.22.013
    Abstract ( 217 )   HTML ( 10 )   PDF (393KB) ( 384 )   Save
    References | Related Articles | Metrics
    【Objective】 To explore the relationship among exogenous selenium, endogenous melatonin, and glutathione oxidation cycle, the effects of selenium valence states and concentrations on melatonin content and glutathione (GSH) redox cycle efficiency in sweet cherry leaves were studied.【Method】Field experiments were carried out at Guangyuan, Sichuan in 2015. Two-year old sweet cherry of ‘Hongmi’ and ‘Brooks’ in orchard were chosen as the experimental materials. Five treatments of water treatment (CK), Se6+ (from Na2SeO4), Se4+ (from Na2SeO3), Se6+ + melatonin, Se4+ + melatonin were designed. The leaves were collected and ground to measure the contents of Se and melatonin after treated 30 days. The vitro experiments were carried out in 2016, and the leaves of two-years old ‘Brooks’ in orchard at Qijiang, Chongqing were selected as materials. For the different treated time experiments, the leaves were placed in 2 mg·L-1 se6+ for 0, 1, 2, 3 and 4 days, and water treatment as control (CK), and the leaves were collected at 10:00 am. every day. For the different Se concentrations treatments, sweet cherry leaves were placed in 0, 0.5, 1.0, 2.0 and 4.0 mg·L-1 se6+ solution for 24 hours and then collected the leave samples. The contents of selenium and melatonin, and substances and enzymes in glutathione redox cycle of all collected samples were measured. 【Result】 Leaves melatonin contents of ‘Hongmi’ and ‘Brooks’ under Se4+ or Se6+ treatments were significantly reduced under field experiment. While leaves melatonin contents of two varieties sweet cherry under Se6++ melatonin or Se4++ melatonin treatments were higher than only Se4+ or Se6+ treatments, respectively. For different time vitro treatment, leaves melatonin contents under Se6+ treatment was significantly higher than control at the first day, but the contents were become lower than water control at 2, 3 and 4 days. At the same time, vitro leaves under 2 mg·L-1 Se6+ concentration for 24 h reduced GSH redox cycle efficiency at first day, via the contents of GSH, oxidative glutathione (GSSG), GSH+GSSG and GSH/GSSG ratio were all lower than control, and the activities of peroxidase (GPX) and glutathione reductase (GR) were also lower than control. But after that GSH redox cycle efficiency started to increase and was higher than control. For different selenium concentrations treatments, the vitro leaves melatonin contents and GSH redox efficiency were reduced with the increased Se6+ concentrations. 【Conclusion】 The selenium contents in leaves of sweet cherry were improved by exogenous selenium treatment, especially the Se6+ treatment. And selenium treatments affected the leaves melatonin contents and the efficiency of GSH redox cycle.
    FOOD SCIENCE AND ENGINEERING
    Effect of Phosphorylation Level on Myoglobin Stability
    LI Meng, LI Zheng, LI Xin, DU ManTing, SONG Xuan, ZHANG DeQuan
    Scientia Agricultura Sinica. 2017, 50(22):  4382-4388.  doi:10.3864/j.issn.0578-1752.2017.22.014
    Abstract ( 258 )   HTML ( 6 )   PDF (508KB) ( 276 )   Save
    References | Related Articles | Metrics
    【Objective】Myoglobin is the main pigment responsible for meat color, which is mainly in sarcoplasm. Meat color is determined by the absolute content and the dynamics of myoglobin redox form interconversions. Studies have shown that protein phosphorylation may play a negative role in meat color development by regulating glycolysis and the redox stability of myoglobin. The effects of phosphorylation on myoglobin stability was investigated in this study, which will provide theoretical basis for improving meat color stability through regulating protein phosphorylation level.【Method】The pure metmyoglobin from skeletal muscle was used. Metmyoglobin was reduced by sodium dithionite, which was then removed by ultrafiltration. After that, alkaline phosphatase (AP) was added to catalyze the dephosphorylation of myoglobin in vitro. The phosphorylation level of myoglobin was determined by using SDS-PAGE and then stained by Pro-Q & Ruby reagent. pH value was measured by a pH meter. The relative content of three myoglobin forms (oxygenated myoglobin, deoxy myoglobin and iron myoglobin) and the secondary structure of myoglobin during the incubation were measured by ultraviolet spectrophotometer and circular dichroism spectrum, respectively.【Result】According to the results, the phosphorylation level of myoglobin was significantly lower (P<0.05) in AP group than that in control group at 6 h, which indicating that alkaline phosphatase can catalyze the dephosphorylation of myoglobin in vitro, thus decrease the phosphorylation level of myoglobin. The relative content of oxymyoglobin in AP group was significantly higher than that in control group, and the relative content of metmyoglobin was significantly lower than that in control group after 2 h. In brief, the automatic oxidation rate of myoglobin was lower and the redox stability of myoglobin was higher in AP group than that in control group. However, no significant difference (P>0.05) was observed betweenAP group and control group, which means that pH value of the incubation system was not changed by adding alkaline phosphatase. The results showed that the secondary structure of myoglobin was mostly α-helix. From 0 min to 6 h incubation, the contents of α-helix and β-sheet of myoglobin were almost unchanged in AP group, while the α-helix content of myoglobin increased and β-sheet content of myoglobin decreased in control group, indicating that the secondary structural stability of Mb was increased after dephosphorylation.【Conclusion】It was speculated that the secondary structure of myoglobin might be changed after phosphorylation. The secondary structure stability was decreased and automatic oxidation rate of myoglobin was increased after phosphorylation. Thus, leading to the accumulation of metmyoglobin and color deterioration, and this might be one of the reasons by which protein phosphorylation play a negative role in regulating meat color stability.
    ANIMAL SCIENCE·VETERINARY SCIENCERE·SOURCE INSECT
    Regulation of the BCKDHB Gene Expression by miR-433-3p in Ovine Preadipocytes
    YAN XiaoRu, SHI Tao, PAN YangYang, JING JiongJie, CHENG LiFen, CAO NingXian, QIAO LiYing, LIU WenZhong
    Scientia Agricultura Sinica. 2017, 50(22):  4389-4397.  doi:10.3864/j.issn.0578-1752.2017.22.015
    Abstract ( 205 )   HTML ( 2 )   PDF (2446KB) ( 294 )   Save
    References | Related Articles | Metrics
    【Objective】 This study aims to reveal the target relationship between miR-433-3p and BCKDHB by theoretical prediction and experimental verification approaches. 【Method】The binding site between miR-433-3p and BCKDHB was predicted by three bioinformatics softwares including TargetScan、miRanda and DIANA-microT based on the sequence of BCKDHB. In order to get the target fragment the primersof BCKDHB 3′-UTR were designed for PCR amplification. Double digestion with Xho I and Xba I was performed with vector Pmir-GLO and target fragments, which were then ligated with T4 enzyme to obtain the recombinant dual-luciferase expression plasmid. Two vectors of mimics and NC were commercially available. One experimental (overexpressing miR-433-3p) and two control groups (negative and blank) were set. By using LipofectamineTM3000 reagent the dual-luciferase vector was co-transfected with the commercially obtained vectors into HEK-293T cells of overexpressing-miR-433-3p and negative groups, respectively. And the cells of blank group were cultured normally. Subsequently, their relative luciferase activities were detected, with renilla luciferase activity as the control. Ovine preadipocytes were cultured in vitro to study the interacting relationship of miR-433-3p and BCKDHB in the differentiated preadipocytes. MiR-433-3p overexpression was adopted to study its regulating function to BCKDHB by detecting RNA quantity of miR-433-3p and BCKDHB as well as protein quantity of BCKDHB before and after miR-433-3p overexpression in ovine preadipocyte. RT-qPCR was carried out to detect the temporal expression dynamics of BCKDHB and miR-433-3p in the differentiation process of ovine preadipocytes . In order to increase the reliability of the results, we also carried out photo collection and oil red O staining at different stages during the differentiation of ovine preadipocytes.【Result】 The results showed that miR-433-3p had a theoretical binding site at the 8~28 bases of BCKDHB 3′-UTR. We found miR-433-3p overexpression significantly (P<0.01) decreased luciferase activity of the recombinant double fluorescent plasmid by comparing the relative fluorescence activity of the overexpression, the negative and the blank groups, indicating that miR-433-3p could bind to the 3′-UTR, which verified the correctness of our prediction. Overexpressed miR-433-3p inhibited the expressions of BCKDHB at both mRNA (P<0.01) and protein (P<0.05) levels in ovine preadipocyte. The expression of miR-433-3p correlated negatively with that of BCKDHB in the process of ovine preadipocyte differentiation. Cellular photos and the oil red O analysis showed lipid droplets accumulated in the differentiation of ovine preadipocytes.【Conclusion】 These results indicated that miR-433-3p negatively regulated the expression of BCKDHB and its coding protein by binding to the 3′-UTR, which provided a scientific basis for further research on the molecular mechanism of BCKDHB in regulating fat metabolism in sheep.
    Identification of the Interactions of CDK11 with RNPS1 and 9G8 in the Silkworm (Bombyx mori)
    ZHANG Qian, LIU TaiHang, DONG XiaoLong, WU YunFei, YANG JiGui, ZHOU Liang, PAN CaiXia, PAN MinHui
    Scientia Agricultura Sinica. 2017, 50(22):  4398-4407.  doi:10.3864/j.issn.0578-1752.2017.22.016
    Abstract ( 246 )   HTML ( 2 )   PDF (4519KB) ( 345 )   Save
    References | Related Articles | Metrics
    【Objective】 The objective of this study is to identify the interactions of silkworm (Bombyx mori) CDK11 with RNPS1 and 9G8, and to lay a foundation for the analysis of whether it is involved in the splicing of precursor RNA. 【Method】 The B. mori gene sequences in this study were found in silkworm genome database SilkDB, and Primer 5.0 was used for primer design. Firstly, two important splicing factors RNPS1 and 9G8 were cloned by PCR and the overexpression vector with different epitope tags was constructed. Then, NCBI was used to retrieve and obtain the relevant sequence of other species. The online prediction software SMART was used for domain prediction. ClustalX 1.83 and GENEDOC 3.2 were used to predict the homologous sequence, and the phylogenetic tree was constructed by software MEGA 6.0. Next, immunofluorescence was used to verify the co-localization of CDK11A and CDK11B with RNPS1 and 9G8, respectively. Finally, the interaction of CDK11A and CDK11B with RNPS1 and 9G8 was further confirmed by immunoprecipitation. 【Result】 The open reading frame of RNPS1 is 882 bp, encoding 293 amino acids. And the open reading frame of 9G8 is 531 bp, encoding 176 amino acids. Both RNPS1 and 9G8 belong to the SR protein family, which has RS domain that contains rich of serine/arginine (S/R) repeats. Homozygous sequence alignment showed that both RNPS1 and 9G8 had a typical RRM domain, and 9G8 also contained a zinc finger domain. Phylogenetic analysis showed that RNPS1 was clustered in an invertebrate, which possessed high homology with other Lepidoptera insects like Pararge aegeria and Danaus plexippus. 9G8 also clustered in an invertebrate, and had close relationship with other Lepidoptera insects like D. plexippus and Papilio machaon. Fluorescence co-localization showed that RNPS1 was co-located in the nucleus with CDK11A and CDK11B, respectively, and had dot-like co-aggregation. While, 9G8 also had a co-localization with CDK11A and CDK11B in the nucleus, respectively. Furthermore, by using immunoprecipitation, it was found that the expression of the corresponding band was detected in all total protein and supernatant samples after cell lysis, indicating that the co-transfected cells were able to express the protein of interest and the protein was dissolved in the supernatant. At the same time, in all the coprecipitation bands, the corresponding target bands could be detected. The above results indicated that both CDK11A and CDK11B interacted with RNPS1 and 9G8.【Conclusion】Both RNPS1 and 9G8 have a typical RRM domain which belong to the SR family. CDK11A and CDK11B have interaction with RNPS1 and 9G8.
    RESEARCH NOTES
    Drought Resistance Evolution of F1 andF2 Hybrids from Five Climatic Ecotypes Saccharum spontaneum L.
    TIAN ChunYan, TAO LianAn, YU HuaXian, DONG LiHua, JING YanFen, BIAN Xin, LANG RongBin, ZHOU QingMing, AN RuDong, SUN YouFang, YANG LiHe
    Scientia Agricultura Sinica. 2017, 50(22):  4408-4420.  doi:10.3864/j.issn.0578-1752.2017.22.017
    Abstract ( 249 )   HTML ( 5 )   PDF (749KB) ( 299 )   Save
    References | Related Articles | Metrics
    【Objective】Drought is an important abiotic factor which has a severe impact on yield and qualities of sugarcane production. Saccharum spontaneum L., a wild resource of sugarcane, possesses a series of characters such as strong stress resistance, excellent perennial root and wide adaptability. Therefore, study on the drought resistance of its progenies, screening of drought resistant germplasms could provide a basis for drought resistance parent selection and realize breakthrough in breeding new sugarcane cultivars. 【Method】In this study, thirty-six F1 andF2 individuals from five ecotypes S. spontaneumwithYunrui innovation parents, introduced species and domestic species were bucket-planted in the greenhouse used as materials. The materials were treated by artificial water stress including normal water supply (as control), mild water stress and severe water stress at the early elongation stage of sugarcane. Subsequently, seven physiological and biochemical indexes including plasma membrane permeability (PMP), contents of malondialdehyde (MDA), chlorophyll (CHL), soluble protein (Pr) and proline (Pro) content and activities of superoxide dismutase (SOD) and peroxidase (POD) in sugarcane leaves were measured. Eventually, the drought resistance of F1 andF2 generations was evaluated comprehensively using fuzzy membership function method, cluster and grey relational analysis.【Result】Under water stress, the PMP, contents of MDA and proline, and the activities of SOD and POD raised, while the contents of CHL and PRO declined with different extents depending on sugarcane genotypes and stress degree. The results of fuzzy membership function analysis indicated that the drought resistance of S. spontaneum progeny varied was different under different water stress degrees, and the drought resistance of F1 generation was stronger than that of F2. The comprehensive drought resistance of individuals exceeded the parental up to 82% in F1, which was much higher than F2. The tested materials were classified into four groups under mild water stress by cluster analysis, and the drought resistance of groups Ⅰ and Ⅱ was the best, followed by group Ⅳ, and the worst was group Ⅲ. Moreover, the individuals of group Ⅲ were all from F2, and all the F1 individuals distributed in groupsⅠ, Ⅱ and Ⅳ, respectively, which had strong drought resistance. Simultaneously, they could be divided into three groups under severe stress, and the F1 individualsexcepted YGF108-473 were all distributed in groups Ⅰ and Ⅲ, which showed stronger drought resistance than group Ⅱ. The grey relation analysis revealed that the correlation between physiological indexes and membership value was different because of water stress degree. Under mild stress, the correlation degree was in the order of POD>SOD>PMP>MDA>Pr>CHL>Pro. But, the correlation degree under severe stress was in the order of SOD>Pr>CHL>POD>PMP>MDA>Pro. 【Conclusion】In all thirty-six tested materials, YGF108-536, YGF211-261, YG F108-391, YGF108-254, YGF211-90, YGF211-8, YGF211-258, YGF108-398, YGF108-543, YGF211-151 and YGF211-53 were exhibited strong resistance under water stress. These materials could be utilized emphatically in parent selection and drought resistance breeding. Furthermore, genetic performance of drought resistance had significant difference between F1 and F2 hybrids of S.spontaneum, and the drought resistance of F1 wasstronger than that of F2. In addition, the drought resistance of S.spontaneum hybrids was no obvious correlation with paternal climate-type, geographic position and altitude. Based on the results of this study, PMP, contents of MDA and CHL, and activities of SOD and POD were good physiological and biochemical indicators with close correlation to drought resistance of sugarcane.
    Research Progresses in mechanisms of Growth Habits and Co Gene Mapping of Columnar Apple (Malus domestica × Borkh.)
    LIANG MeiXia, QIAO XuQiang, GUO XiaoTong, ZHANG HongXia
    Scientia Agricultura Sinica. 2017, 50(22):  4421-4430.  doi:10.3864/j.issn.0578-1752.2017.22.018
    Abstract ( 384 )   HTML ( 8 )   PDF (421KB) ( 301 )   Save
    References | Related Articles | Metrics
    Columnar apple is a dwarfed mutant with thick, upright main stems and shortened internodes, and generates short fruit spurs instead of long lateral branches. It is a good resource for high dense planting and high yield production in the modern apple industry. Therefore, to understand its unique growth habit was highly interested for all research groups. The current research achievements are summarized as follows: (1) The growth habits of columnar apple is closely related with its endogenous hormones. The free IAA to total IAA ratio was found higher in the axillary buds of columnar apple trees than in the standard type apple trees. The columnar apple producing high number of spurs is because the higher level of zeatin-like growth substances exists in both apical and lateral shoots. The dwarfed growth phenotype is probably correlated with the lower GA level in the columnar apple trees. (2) The columnar phenotype is controlled by a single dominant allele of the columnar gene, which is clustered with the genes controlling main stem growth, branching habit, leaf feature and fruit quality. The Co gene has been fine-mapped to chromosome 10 within the region of 18.51-19.09 Mb. (3) Five Co candidate genes has been reported till today. As the observation that expression of 91071 in apple and tobacco led to shortened internodes in transgenic plants, 91071 was taken as the most promising Co candidate gene, although more studies are needed to clarify whether the 91071 gene also causes the reduced lateral branches and increased spurs in columnar apple. Since co gene is closed related with both plant hormone metabolism and signal transduction, studies on its biological functions by RNAi and transgenic technologies can not only reveal the molecular mechanism of the unique growth characteristics of columnar apple tree, but also provide the theoretical basis for the molecular breeding of columnar apple with improved quality.