Scientia Agricultura Sinica

Association Analysis of Rice Cooking Quality Traits with Molecular Markers

GAO WeiWei, CHEN SiPing, WANG LiPing, CHEN LiKai, GUO Tao, WANG Hui, CHEN ZhiQiang

Scientia Agricultura Sinica. 2017, 50(4): 599-611. doi:10.3864/j.issn.0578-1752.2017.04.001

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【Objective】 In this study, the variation of major grain-quality traits and RVA profiles of representative rice germplasm were investigated, molecular markers significantly associated with the traits were identified, aiming to provide an important foundation for improvement of grain quality of rice. 【Method】 Global grain-quality properties and their differences were surveyed with a rice panel consisted of 48 diverse germplasms collected from both China and abroad. Starch RVA profile was examined with a Rapid Visco Analyzer. The markers reported to be related to starch biosynthesizing genes and QTLs for development of rice grain were used for genotyping. Trait-marker association for grain-quality properties was detected using the general linear model with Tassel 3.0 software. Moreover, stepwise regression analysis was performed with these detected markers significantly associated with grain-quality traits. The phenotypic effects of the alleles and allelic combinations were estimated and both elite alleles and typical carrier genotypes were identified. 【Result】There were wide phenotypic variance and diversity in amylose content (AC), gel consistency (GC) and alkali spreading value (ASV), and the coefficient of variation (CV.) ranged from 26.5% to 36.3%. Based on inspection of RVA profile, significant differences were found in breakdown (BDV), setback (SBV) and consistence (CSV), and these parameters have preferably reflected the diverse starch paste properties among different rice varieties. Correlation analysis showed the AC was positively correlated with cool paste viscosity (CPV), SBV and CSV, while negatively correlated with peak viscosity (PKV) and BDV. The GC was negatively correlated with SBV and CSV. A total of 491 alleles were identified with 154 polymorphic markers, with an average gene diversity of 0.447 and an average polymorphic information content of 0.390. Based on the analysis of trait-marker association, a total of 22 markers were detected to associate with grain-quality traits, which explained the phenotypic variance ranged from 14.11% to 75.62%. The GBSSI gene majorly affected the properties of AC and GC, and the SNP marker of Wx-G/T explained up to 61.44% and 41.87% of the phenotypic variation for AC and GC, respectively. While the SSIIa was the major gene affecting ASV, and the phenotypic variation of ASV explained by the markers of alk-GC/TT and SSIIa-F was up to 75.62% and 74.46%. The model equations based on stepwise regression analysis of AC, GC and ASV were developed using the significant markers, whose determination coefficients were 85.30%, 40.62%, and 80.38%, respectively. 【Conclusion】The starch RVA profile wass closely related to AC, GC and ASV. The RVA profile can be used to evaluate rice quality traits more comprehensively. With trait-marker association analysis, 22 markers were detected to be associated with grain-quality traits, and five of these sites were associated with both AC and GC. Regression models showed allelic combination can produce different phenotypic effects.

Effects of Sowing Dates on Panicle Differentiation and Leaf Number Index of Summer-Sowing Foxtail Millet [Setaria italica (L.) Beauv.]

LI GuoYu, CONG XinJun, QIN Ling, ZOU RenFeng, YANG YanBing, YAN LiMei, CHEN ErYing, LI Ni, GUAN YanAn

Scientia Agricultura Sinica. 2017, 50(4): 612-624. doi:10.3864/j.issn.0578-1752.2017.04.002

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【Objective】The panicle differentiation of summer-sowing foxtail millet and its relationship with leaf number index were investigated under different sowing times, so as to provide an application basis for millet production and growth simulation.【Method】Summer-sowing foxtail millet varieties Jigu 16 with sethoxydim resistance and Jigu 18 with waxy endosperm were used as materials, which were planted in plots in the order of sowing time in Jinan Experiment Station of Crop Research Institute, Shandong Academy of Agricultural Sciences. Eight sowing treatments were applied during April 29 to July 8, 2015 at the interval of 10 days. Plant density was set at 600 000/hm2. One hundred and twenty uniform seedlings at five-leaf stage were tagged in each plot for sampling. Thereafter, 3 to 5 plants were sampled at the interval of 1 to 2 days until heading. The young leaves were deliberately stripped till the young inflorescence fully presented under the OLYMPUS SXZ16 digital stereoscopic microscope to observe the morphological development of young inflorescence, and the leaf number and leaf number index were determined at different stages. The total leaf number was recorded at mature stage.【Result】The sowing date and varieties had no effect on the development pattern and morphological characteristics of the panicle differentiation in summer-sowing foxtail millet. Based on panicle differentiation characteristics of vegetative stage, elongation stage, panicle branch differentiation stage, spikelet and bristles protuberances stage and gynoecium and stamen formation stages, the young panicle development process was clearly and systematically characterized by referring series pictures of Jigu 16 panicle differentiation. The influence of sowing date on foxtail millet was predominantly incurred by the starting date and lasting time of young panicle differentiation. With sowing date delayed, the starting date of panicle differentiation was advanced from 32 days to 22 days after germination compared the earliest sowing treatment with the latest sowing treatment. The lasting time of panicle differentiation process was shortened from 28 days to 19 days. And the growth duration was from 109 days to 83 days. The changing tendency of leaf number and leaf number index showed a significant difference at each panicle differentiation stage, and the relationship of panicle differentiation stage with corresponding leaf number index was relatively stable in various sowing treatments. The regression analysis showed significant differences and positive linear correlation at 0.01 level between the panicle differentiation stage and leaf number index for each variety in different sowing treatments. The value of R2 was in the range of 0.977 to 0.997. The linear regression formula of young panicle differentiation stage (Y) to leaf number index (X) was as follows: Y= bX+a, and the linear regression relationship of panicle differentiation stage with leaf number index could not be expressed by a same formula for Jigu 16 and Jigu 18 with different sowing times.【Conclusion】The development pattern of panicle differentiation of two summer-sowing foxtail millet varieties was basically similar, however, the influence of sowing dates on panicle differentiation was different. The time difference of panicle differentiation stages caused by sowing date primarily determined the growth duration. Panicle differentiation stages of foxtail millet could be forecasted according to leaf number indexes.

Drought Resistance of Sesame Germplasm Resources and Association Analysis at Adult Stage

LIU WenPing, Lü Wei, LI DongHua, REN GuoXiang, ZHANG YanXin, WEN Fei, HAN JunMei, ZHANG XiuRong

Scientia Agricultura Sinica. 2017, 50(4): 625-639. doi:10.3864/j.issn.0578-1752.2017.04.003

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【Objective】By association mapping between 33 SSR markers and 18 sesame drought-resistance phenotypes, identifying the associated loci, providing a basis for drought-resistance gene mapping and functional marker development, identifying drought-resistant sesame germplasm resources and providing parental materials and varieties for drought-resistance breeding.【Method】Sesame germplasm populations were cultivated using pots and stressed by drought-water-drought duplication treatment, morphology and growth index during the drought-stress period and mature period were analyzed, then the combination method of SAS, SPSS, and membership function were used for drought-resistance evaluation. At the same time, association analysis was carried out using GLM and MLM models based on molecular markers and drought-resistance phenotype data.【Result】After drought stress, obviously different responses were observed among materials in the population, each index that related to drought resistance averaged smaller than the control; the averaged coefficient of variation of 18 traits was 0.31, which was higher than the control. T test of all traits between treatment and control showed a significant difference. A total of 10 indices related to drought-resistance were screened out, and 12 germplasms with high drought-resistance were identified by functional and clustering analysis. A total of 170 loci were detected by 33 SSR makers in the tested materials, the average loci number was 5.15 per marker. Genetic structure analysis indicated that the population consists of 2 sub-groups. There were 120 loci and 63 loci that were detected by association analysis based on GLM model and MLM model, respectively, the explanation rate ranged from 3.85% to 14.3%, and from 4.00% to 12.5%. There were 12 loci and 3 loci were detected with higher explanation rate than 10% by GLM and MLM, respectively, 5 loci were detected simultaneously by GLM and MLM. By comparison of the primers sequences with sesame genome, 3 genome regions were presumed located genes related with drought-resistance.【Conclusion】This research selected 12 sesame germplasms with high drought-resistance by comprehensive evaluation method, at the same time, 4033-3 and 4033-2 loci that were detected with the highest explanation rate by association analysis based on GLM model and MLM model, respectively, and the explanation rate were 14.3% and 12.5%.

Effects of Soil Water Deficit on Insecticidal Protein Expression in Boll Shell of Transgenic Bt Gene Cotton

ZHANG Xiang, HU DaPeng, LI Yuan, ZHANG LiYa, WANG Jian, CHEN Yuan, CHEN DeHua

Scientia Agricultura Sinica. 2017, 50(4): 640-647. doi:10.3864/j.issn.0578-1752.2017.04.004

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【Objective】 The effects of soil water deficit on insecticidal protein expression in boll shell of Bt gene cotton were studied. 【Method】 In 2014 and 2015, two Bt cotton cultivars Sikang 1 (a conventional cultivar) and Sikang 3 (a hybrid cultivar) were selected as experimental materials and were planted in pots. In 2014, five soil water contents were designed at boll peaking stage: 15% of maximum capacity of soil moisture (G1), 35% of maximum capacity of soil moisture (G2), 40% of maximum capacity of soil moisture (G3), 60% of maximum capacity of soil moisture (G4), 75% of maximum capacity of soil moisture (CK), respectively. Four treatments (G2, G3, G4, CK) were set in 2015. The effects of soil water deficit on insecticidal protein content in boll shell were determined. Ten days before flowering peak stage, watering should be controlled in each treatment. The pots were moved indoors in case of rain. At the same time, the soil water contents were monitored by WET sensor. When the soil water contents were below the designed value, the pots were watered in the morning, at noon and in the evening. On the basis of these studies, the effects of soil water deficit on Bt gene expression, activities of nitrogen metabolism-related enzymes were determined in 2015. 【Result】 The results of the two years experiments showed that the insecticidal protein content of boll shell decreased with water deficit level increasing. Compared with the control (75% of maximum capacity of soil moisture), the boll shell insecticidal protein content decreased significantly when the soil water content was below 60% of maximum capacity of soil moisture. In comparison with the control, the insecticidal protein contents of cultivar Sikang 1 and Sikang 3 decreased by 22.5% and 41.6%, respectively, with the soil water content at 60% of maximum capacity of soil moisture. However, larger increments of Bt gene expression were observed when the boll shell insecticidal protein content was significantly reduced. Compared with that of respective control, the levels of Bt gene expression in Sikang 1 and Sikang 3 increased by 48.6% and 22.1%, respectively. Furthermore, the key enzyme activity of the nitrogen metabolism showed that the boll shell protease and peptidase increased but the activities of nitrogen reductase and GPT activities decreased. There existed a significant positive correlation of insecticidal protein content with nitrogen reductase and GPT activities; and a significant negative correlation of protease and peptidase activities with insecticidal protein content. 【Conclusion】 Under the condition of soil water deficit, the boll shell insecticidal protein content decreased significantly. However, the expression levels of Bt gene in the two cultivars increased significantly. NR and GPT activities decreased, while protease and peptidase activities increased. Thus, the decrease of insecticidal protein content was considered as a results of decrease of synthesis and increase of decomposition of protein.

Effects of Rice Stubble Height on Growth, Development, and Yield Components of Interplanted Rapeseed in Rice

ZHENG Wei, XIAO GuoBin, XIAO XiaoJun, LI YaZhen, CHEN Ming, LIU XiaoSan, HUANG TianBao, WU Yan, YE Chuan, ZHU ChangLan

Scientia Agricultura Sinica. 2017, 50(4): 648-656. doi:10.3864/j.issn.0578-1752.2017.04.005

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【Objective】Under the pattern of interplanting rapeseed in late rice, standing stubble height affected soil water storage and preservation, interplanting rapeseed emergence rate, growth and development. This study aimed at finding out a proper standing stubble height to promote emergence rate, growth and development, and finally to improve yield of interplanting rapeseed. These results provide practical references for reaching efficiency and organic combination of agronomy with agricultural machinery.【Method】Fengyou 730, a elite rapeseed cultivar, was employed in a field experiment with four stubble height treatments during the 2014-2016 growing seasons at Jiangxi Institute of Red Soil, Jiangxi province. Four stubble height treatments were compared: 20, 30, 40 and 50 cm. The seedling rate, mature plant rate, agronomic traits at two growth stages (wintering stage and full bloom stage), chlorophyll content of leaves, root activity, yield were measured in this study.【Result】In the range of 20-50 cm, an increased stubble height could thoroughly promote the seedling density, the seedling rate and mature plant rate were increased at the initial stage but deteriorated under a further increased stubble height, the optimal seedling rate and mature plant rate were the treatment with stubble height of 40 cm, the mature density was relatively larger. The seedling rate and mature plant rate of 40 cm stubble height were 13.73%, 7.09% and 13.18%, 7.23% higher than that of 20 cm and 30 cm, respectively, but the differences were not significant between 40 cm and 50 cm. Stubble height significantly affected growth and development of interplanted rapeseed. The number of total leaves, number of green leaves, width of maximum leaf, crown diameter, the dry weight of individual plants and the chlorophyll content of the top 3 leaves, root activity were gradually fell, the length of maximum leaf was gradually increased, the leaf area index and dry matter of population plants were primitively increased and then subsequently fell with increasing of the stubble height. The yield per plant of interplanted rapeseed in rice was diminished, whereas the yield per area was heightened initially and diminished later with increasing of the stubble height, and the optimal rapeseed yield could be approached with stubble height of 40 cm. Compared with the stubble height of 20 cm, the yield increasing rate of the stubble height of 40 cm was 18.92%, the yield increased obviously. Stubble height was highly related to yield components of interplanted rapeseed in rice including primary branches, siliques per plant, siliques on main inflorescence, 1000-grain weight, dry matter weight per plant, and yield per plant with a substantial negative correlation or significant negative correlation.【Conclusion】A lower seedling rate, mature plant rate and mature density, but strong individuals under a lower stubble height as well as a higher mature density and weak individuals under a higher stubble height could result in yield reduction. Results of the study indicated that late rice stubble height of 40 cm was helpful to population growth and strongly improved the yield of interplanted rapeseed.

Agricultural IOT Architecture and Application Model Research

ZHENG JiYe, RUAN HuaiJun, FENG WenJie, XU ShiWei

Scientia Agricultura Sinica. 2017, 50(4): 657-668. doi:10.3864/j.issn.0578-1752.2017.04.006

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Agricultural Internet of Things (AIoT) is the highly integrated information technology such as computer, internet and mobile communication’s application in agricultural field, and it is the essential condition for the agricultural informatization and intelligent. With the development of AIoT industry, there appears an endless stream of AIoT application systems, because of the lack of analysis for AIoT system’s whole architecture, the current AIoT application presents the fractional, vertical and heterogeneous characteristics. Extracting the system components and their relationship from various AIoT applications, and establishing AIoT system architecture, to achieve the AIoT’s design and realization method’s unification are urgent problems need to be solved. The paper analyzed the AIoT’s concepts, basic features and system structure research status, and found that the IoT development and management plans from different countries and institutes played good guidance for the related researchers, however, they didn’t give the specific methods that can design and realize the IoT systems, and furthermore agricultural environment’s diversity and complexity determine that AIoT architecture’s establishment must consider agricultural industries characteristics as a whole. Therefore, the paper firstly discussed the agricultural architecture building principles including extensibility, reusability, safety and reliability and so on, then combined with the specific needs of agricultural industry and experiences from engineering practices, put forward an AIoT hierarchical structure model, the model is divided into five layers from the bottom to the up, they are perception layer, access layer, network layer, data layer and application layer, respectively, and each layer corresponds to different communication protocols. And pointed out that AIOT hierarchical model and the corresponding protocol architecture constitute the AIoT architecture. Compared with the traditional three layers and four layers architecture, the proposed architecture added the access layer and data layer. Aiming at the problem that the majority objects in the ubiquitous environment have limited resources and computing power, the access layer emphasized that the underlying heterogeneous sensor networks can connect to the network layer seamlessly, it provides a unified abstract management interface to shield the complexity of the underlying heterogeneous sensor networks, and reduces the difficulty of building AIOT perception system. For the problem of agricultural data can not be fully used in current AIoT systems, and formed the information islands, the data layer designed and realized a service oriented architecture to solve the data exchange and sharing problems among different AIoT systems. Overall the five layers architecture’s functionalities are more independent, it is advantageous to the network load balancing between each layer, and reducing the burden of enterprise network communications. Aiming at the common problems of the application of agricultural industries, according to the different objects to be monitored, analyzed the agricultural production environment monitoring IoT, plant and animal life information monitoring IoT, agricultural products quality detection and the quality safety tracing IoT, agricultural machinery operation monitoring IoT’s present research situation and main technologies involved. From the perspective of agricultural application architecture, it was found that the current researches are more concentrated on the gateway hardware, and the embedded gateway middleware application is relatively few on the one hand, on the other hand the AIOT data sharing layer’s research is seriously lacking, each application system usually sent the perceive data directly to the AIOT application layer, therefore it is difficult to achieve the effect of further guiding to agricultural production for the lack of data mining and analysis. Finally, the paper discussed the further research and application direction of the AIoT technology.

Identification of Homeobox Transcription Factor Family in Genome-Wide and Expression Pattern Analysis of the Members in Setosphaeria turcica

ZHAO Jie, ZHAO LiQing, GONG XiaoDong, FENG ShengZe, LIU XingChen, ZHENG YaNan, LI ZhiYong, SUN HaiYue, WANG DongXue, HAN JianMin, GU ShouQin, DONG JinGao

Scientia Agricultura Sinica. 2017, 50(4): 669-678. doi:10.3864/j.issn.0578-1752.2017.04.007

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【Objective】 The objectives of this study are to identify Homeobox transcription factor family from Setosphaeria turcica genome, and to predict the locations of their corresponding coding proteins in the cells, gene structure and evolutionary characteristics, as well as to explore their expression patterns at different growth and development stages in S. turcica. 【Method】Homeobox transcription factor family was identified based on S. turcica genome database and bioinformatics methods. Phylogenetic tree were created using the MEGA5.0 program. Gene structure characteristics were analyzed by GSDS software, which was a gene structure display server online (http://gsds1.cbi.pku.edu.cn/index.php). Amino acid sequence characteristics of the genes in Homeobox transcription factor family were compared using software Clustal X 1.83. The secondary structures of homeodomain proteins were predicted by employing software SOMPA. Three-dimensional structures of Homeobox transcription factor family were doped out using Software I-TASSER. Homeobox genes expression patterns were detected at different developmental stages based on quantitative real-time PCR (qRT-PCR) analysis. 【Result】 A total of 8 Homeobox genes were systematically identified from S. turcica genome and classified into 4 groups according to the gene structure and phylogenetic tree. Subcellular localization showed that all of the predicted proteins located in the cell nuclei. The family members contained conserved Homeobox domains and typical “helix-turn-helix” secondary structures. Different gene family members took on different expression levels at different development stages in S. turcica. The expression level of StHTF1 was significantly higher at mycelium, spore and appressorium formation stages than other stages. StHTF3, StHTF4 had the highest expression level at spore formation stage than other stages in S. turcica, while StHTF6 was the highest at germ tube formation stage. Moreover, StHTF2, StHTF5, StHTF7 and StHTF8 appeared higher expression level at appressorium formation stage than other genes. 【Conclusion】 Homeobox transcription factor family in S. turcica contains 8 genes which are classed into 4 categories and located in the nuclei. The proteins encoded by the genes contain conserved Homeobox domain and “helix-turn-helix” spatial structure. Homeobox gene family members in S. turcica appeared diverse expression profiles which will lay the foundation for identifying the functions of the gene family.

Development of Padlock Probe Combined with Dot-Blot Hybridization Based Methods for Detection of Bacterial Spot of Melon Leaves

XU Rui, HU BaiShi, TIAN YanLi, HUANG YanNing, XIE Jin, CAO Liang, PENG SiWen, ZHU XiaoQi

Scientia Agricultura Sinica. 2017, 50(4): 679-688. doi:10.3864/j.issn.0578-1752.2017.04.008

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【Objective】 Bacterial spot of melon leaves caused by Pseudomonas syringae pv. lachrymans is distributed widely in the world and inflicts different degrees of damage. P. syringae pv. lachrymans is a typical seed-borne pathogen.The objective of this study is to build effective, commercially viable and convenient detecting technologies and to prevent the spread of this pathogen.【Method】The house-keeping gene of DNA glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was selected as the target gene, the specific Padlock probe was designed for bacterial leaf spot of melon, and a bacterial detection system based on Padlock probe combined with dot-blot hybridization was developed. The target strain was selected as experimental materials, and DNA was extracted as a template for ligation reaction, enzyme-cleavage reaction and amplification reaction. The reaction temperature and reaction time of the ligation reaction, enzyme-cleavage reaction and amplification reaction were optimized. The optimized reactions were tested for healthy melon seeds, melon seeds with bacterial spot of melon leaves, sterile water and 25 experimental strains. In order to determine the sensitivity of padlock probe, DNA of the target strain was diluted to 1 ng·μL^-1, 100 pg·μL^-1, 10 pg·μL^-1, 1 pg·μL^-1, 100 fg·μL^-1, 10 fg·μL^-1 and 1 fg·μL^-1 as the templates. Sensitivity was determined by optimized ligation reaction, enzyme-cleavage reaction and amplification reaction. Padlock probe combined with dot-blot hybridization was developed, the amplification product in the course of the reaction was fixed on the nylon membrane, the reverse complementary sequence of the Zipcode sequence was synthesized into cZipcode (detection probe), the detection probe (cZipcode) was labeled with digoxigenin and hybridized with the amplified product. Padlock probe combined with dot-blot hybridization techniques were used for specific detection and sensitivity. Artificial infestation seeds were detected to further verify the reliability of the system. A total of 205 commercially melon seeds with suspected disease were detected by high throughput detection method.【Result】The specificity of the Padlock probe showed that a specific band of 105 bp was got from 26 strains of bacterial spot of melon leaves, while the remaining 25 strains and sterile water were not amplified products. the results of sensitivity showed that the target strain was diluted to 1 pg·μL^-1 and got a specific band of 105 bp, so the detection sensitivity of the Padlock probe was 1 pg·μL^-1. Padlock probe could distinguish bacterial spot of melon leaves from all other experimental strains and its sensitivity could be up to 1 pg·μL^-1. Twenty-six strains of bacterial spot of melon leaves had color reaction, the remaining 25 strains and sterile water did not have color reaction. The sensitivity of Padlock probe combined with dot-blot hybridization also could be up to 1 pg·μL^-1. Padlock probe combined with dot-blot hybridization could detect one bacterial seed from 1 000 healthy seeds, and the detection rate reached 0.1% (1/1 000). Seven commercially seed-borne bacteria were successfully detected from 205 commercially melon seeds. The seven seed-borne bacteria, respectively, were soaked in sterile water for 4 h, DNA was extracted for PCR amplification and sequencing, the results of DNA sequencing were compared with NCBI and verified the bacterial spot of melon leaves. 【Conclusion】Detecting system based on padlock probe combined with dot-blot hybridization could detect P. syringae pv. lachrymans from sweet melon fast and accurately.

Effect of Different Potassium Levels on the Growth of Bok Choy Under Negative Pressure

ZHAO XiuJuan, SONG YanYan, YUE XianLu, ZHANG ShuXiang, WU XuePing, LONG HuaiYu

Scientia Agricultura Sinica. 2017, 50(4): 689-697. doi:10.3864/j.issn.0578-1752.2017.04.009

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【Objective】Negative pressure irrigation is a new type of water supply technology. In this paper, the effects of five different potassium levels on growth, quality, nutrient uptake, utilization ratio and antioxidant enzyme activity of bok choy were compared. 【Method】In this experiment, five K fertilizer treatments including K0, K1, K1.5, K2 and K3, and 4 water supply treatments including 0, -5, -10, and -15 kPa were designed to study the effects of different potassium levels on bok choy growth. 【Result】(1) The soil moisture in clay loam under different pressures of water, respectively, was 28.52%, 22.45% and 18.13%, 15.4%, and when water pressures were between -5 and -10 kPa, the soil moisture was 18.13%-22.45%, which was suitable for crop growth. (2) The effect of different potassium levels on bok choy yield was significant, and that in K1.5 treatment was the highest, and increased by 16.9% compared with K1. The yield in K3 treatment was significantly decreased. (3) The effect of different potassium levels on the nitrate content of bok choy was significant, and potassium could significantly reduce nitrate content, nitrate content in K1.5 treatment decreased by 26.3% compared with that in K1. (4) Different potassium levels significantly affected the amount of nutrients uptake, nitrogen and potassium absorption of K1.5 were increased by 15.8% and 76.3% compared with that in K1. Phosphorus uptake in K1.5 treatment was less than that in K1. (5) K1.5 improved K utilization of crop by 173.32% compared with K1, and K1.5 significantly improved the agronomic efficiency of fertilizer, and increased by 83.9% compared with K1. (6) Compared to K1, K1.5 significantly increased the expression of the activities of POD, SOD, PPO, and PAL, but the flavonoid and total phenolic was not different with K1. 【Conclusion】 It was concluded that K1.5 was the best potassium application level. The optimum water supply pressure was -10--5 kpa kPa for clay loam.

Nitrogen Deposition in Suburban Croplands of Hebei Plain

YIN Xing, ZHANG LiJuan, LIU XueJun, XU Wen, NI YuXue, LIU XinYu

Scientia Agricultura Sinica. 2017, 50(4): 698-710. doi:10.3864/j.issn.0578-1752.2017.04.010

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【Objective】As the rapid intensification of human activities induced the increase of active atmospheric nitrogen, the atmospheric nitrogen deposition has increased significantly, and consequently the response of the regional ecosystems has gradually become obvious. The objective of this study is to investigate the dynamics of wet and dry deposition of atmospheric nitrogen in Hebei plain, to provide a scientific basis for the integrated management of farmland nitrogen resources, and also to provide basic data for the nitrogen deposition network in China.【Method】Experiments of N wet deposition (2006-2011) and dry deposition (2011) were carried out in the experimental teaching base of Hebei Agricultural University in Baoding areas. N wet deposition was collected by a standard rain gage. DELTA active sampling systems were used to collect NH₃, HNO₃, pNH₄⁺and pNO₃^-. NO₂ samples were collected using Gradko diffusion tubes at sampling sites.【Result】The period from June to September is the rainy season in Baoding area of Hebei, accounting for 88.6%, 81.5%, 89.3%, 88.9%, 74.5% and 83.1% of the annual rainfall in 2006-2011. Monthly N concentration in precipitation was higher in winter and spring than that in summer and autumn, the proportions of NH₄⁺-N、NO₃^--N、TIN and TDN in spring and winter were 74.5%, 72.6%, 74.1% and 71.3%, respectively. The amount of N wet deposition also had an obvious seasonal change, with higher in summer and lower in winter. Annual N wet deposition ranked by the sequence of TDN (total dissolved N) ＞ TIN (total inorganic N) ＞ NH₄⁺-N ＞ NO₃^--N, and had a significant negative correlation with rainfall. The annual N wet deposition during 2006-2011 averaged 32.8 kg N·hm^-2, with the maximum value of 40.4 kg N·hm^-2in 2008 and the minimum value of 28.9 kg N·hm^-2 in 2010. The TIN accounted for more than 75% of TDN deposition,NH₄⁺-N is the major component of TIN accounting for 56.6%-69.7% of the total amount, with an average of 64.4%. Monthly N wet deposition was positively correlated with rainfall and rainfall frequency. Atmosphere concentrations of reactive N (e.g. NH₃, NO₂, HNO₃, pNH₄⁺, pNO₃^-) and their dry deposition also showed large seasonal variations. In general, annual N dry deposition of gases (NH₃, NO₂ and HNO₃) and particles (pNH₄⁺ and pNO₃^-) were 10.1, 7.60, 4.39, 6.47 and 3.81 kg N·hm^-2, respectively. 【Conclusion】The Baoding area deposition contents of nitrogen in atmosphere were affected both by industrial and by agricultural fertilizers, and determined by wet and dry deposition. Atmospheric nitrogen deposition was higher in Baoding area of Hebei, the annual mean N wet deposition was 28.9 kg N·hm^-2(2010) to 40.4 kg N·hm^-2(2008), and the averaged N wet deposition (2006-2011) was 32.8 kg N·hm^-2. The N dry deposition was 32.3 kg N·hm^-2 in 2011, and annual N wet and dry deposition were up to 58.6 kg N·hm^-2 in Baoding, Hebei Plain.

Effects of Biochar and Chitin Combined Application on Malus hupehensis Rehd. Seedlings and Soil Environment Under Replanting Conditions

WANG YanFang, XIANG Li, XU ShaoZhuo, WANG Sen, WANG XiaoWei, CHEN XueSen, MAO ZhiQuan, ZHANG Min

Scientia Agricultura Sinica. 2017, 50(4): 711-719. doi:10.3864/j.issn.0578-1752.2017.04.011

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【Objective】 The experiment was conducted to explore the effects of biochar and chitin combined application on the plant biomass, root respiration rate, root protective enzymes and soil environment under replanting conditions, and to provide a basis for prevention of apple replanting disease (ARD). 【Method】 The Malus hupehensis Rehd. seedlings were planted in pots with apple replanting soil. The experiment included 5 treatments, which were the control (CK), 1‰ chitin (T1), 2% biochar (T2), 1‰ chitin + 2% biochar (T3) and methyl bromide sterilization (T4). The biomass, root respiration rate and protective enzymes activities of M. hupehensis seedlings were measured by conventional method. The number of microorganism, fungal group structure and the Fusarium oxysporum numbers were detected by terminal restriction fragment length polymorphism (T-ＲFLP) and a real-time quantitative PCR detection system. 【Result】 The results showed that compared with the control, T3 and T4 significantly enhanced the plant height, ground diameter, fresh and dry weight, and that in T3 increased by 44.6%, 33.0%, 76.8% and 77.1%, and in T4 increased by 73.1%, 76.9%, 117.0% and 123.7%, respectively. T1, T2, T3 and T4 treatments made the root respiration rate increased significantly, which were 1.37, 1.70, 1.87 and 2.02 times more than the control. The four different treatments also increased the root activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and the increase reached a significant difference. The SOD, POD and CAT activities of T4 treatments were 1.34, 2.68 and 2.64 times compared with the control, and T3 were 1.21, 2.52 and 2.18 times, respectively. T2 and T3 improved the numbers of bacteria, enhanced the ratio of bacteria and fungi and made the soil become “bacterial soil”. The ratios of T3 and T4 were 1.7 and 2.2 times as large as the control, methyl bromide sterilization made the numbers of bacteria and fungi decreased significantly, and the fungi numbers decreased more than bacteria’s, so the bacteria/fungi ratio was higher than the control. T4 had the highest Shannon diversity index, evenness index and richness index, increased by 24.4%, 41.3% and 13.6% compared with CK, and the second was the T3 treatment. Compared with the control, T3 and T4 reduced the gene copie’s number of F. oxysporum, which explained that the F. oxysporum harmful fungi number decreased significantly in replanting soils. Compared with CK, the concentration of phlorizin, phloretin, cinnamic acid, p-hydroxybenzoic acid and phloroglucinol reduced by 28.1%, 30.6%, 50.8%, 33.6% and 46.2% in T3, respectively.【Conclusion】The biochar and chitin combined application improved the condition in apple replanting soil better than solely biochar or chitin addition. The combined application improved the M. hupehensis. seedlings biomass, root respiration rate and root activity of protective enzymes. And the combined application optimized the soil fungi community structure, increased the soil bacteria/fungus ratio, and reduced the F. oxysporum gene copy numbers and contents of phenolic acids. Therefore, biochar and chitin combined application can better relieve ARD.

Effects of Different Processing Techniques and Collecting Periods on the Aroma Constituents of Rosa damascena Flower Water

LI AiPing, XU XiaoYu, CHEN Zheng, YU XiuHong, HUANG XuMin, ZHENG KaiBin

Scientia Agricultura Sinica. 2017, 50(4): 720-731. doi:10.3864/j.issn.0578-1752.2017.04.012

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【Objective】 The objective of this experiment is to clarify the impacts of different extraction processes (water steam distillation and coeno-water distillation) and collecting periods on the aroma constituents of Rosa damascena flower water, and to provide reference for the reasonable processing and utilization of rose water. 【Method】 The dominant aroma compositions of R. damascena flower water from different extraction processes and collecting periods were identified and quantified by using the following methods: sampled by solid phase micro extraction first, then the constituent was isolated by gas chromatography- mass spectrometry (GC-MS), and each constituent was retrieved and analyzed by the computer spectral database (NIST/WILEY), finally confirmed artificially referring to data. 【Result】 Types and relative percentage of aroma constituents of R. damascena flower water extracted by water steam distillation were all higher than that extracted by coeno-water distillation, as well as the relative percentage of geraniol and benzyl alcohol. Therefore, R. damascena flower water extracted by water steam distillation was rich in aroma and sweet smell, and the quality was superior to that extracted by coeno-water distillation. Whether R. damascena flower water extracted by coeno-water distillation or water steam distillation had the maximum quantity and content of alcohols in the second period. However, the main aroma of R. damascena flower water extracted by coeno-water distillation and collected in the second period was the strongest, while the main aroma of R. damascene rose water extracted by water steam distillation and collected in the first period was as strong as that collected in the second period. Therefore, R. damascena flower water extracted by coeno-water distillation and collected in the second period (the second weight which is equal to flowers) had the best quality, and the first (the first weight which is equal to flowers) and second periods were suitable for collecting in the production of rose water. While R. damascena flower water from the first period (the first weight which is equal to flowers) extracted by water steam distillation had the best quality, and the first, second and third periods were suitable for collecting in the production of rose water. 【Conclusion】 The aroma of R. damascene rose water extracted by water steam distillation is superior to that extracted by coeno-water distillation. R. damascena flower water extracted by coeno-water distillation and collected in the first two periods is applicable in the production, while rose water extracted by water steam distillation and collected in the first three periods is applicable.

Effects of Phenolic Acids on Copigmentation and Stability of Anthocyanins in Red-Fleshed Apple

SU Fan, XUE Jia, YANG Xi, DENG Hong, MENG YongHong, GUO YuRong

Scientia Agricultura Sinica. 2017, 50(4): 732-742. doi:10.3864/j.issn.0578-1752.2017.04.013

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【Objective】‘Zihong NO.1’ red-fleshed apple is cultivated widely in Xinjiang Autonomous Region of China. Through investigating copigmentation of phenolic acids on anthocyanins in red-fleshed apple and their stability, this paper aims at providing a theoretical basis and reference for industrial utilization of red-fleshed apple anthocyanins. 【Method】 Ultrasonic-assisted method was used to extract anthocyanins, and pH differential method was adopted to determine the total content of red-fleshed apple anthocyanins. Besides, the constituents of red-fleshed apple anthocyanins and content of monomeric anthocyanins were also analyzed by HPLC. In phosphate buffer (pH 3.0) of red-fleshed apple anthocyanins, the copigmentation effect of these four acids was evaluated. The absorption spectra and absorbance at λ_max of all treatment groups as well as the contrast groups were measured before and after the treatments of heating, light exposure, oxidation and adding metal ions (Fe³⁺).【Result】The content of total anthocyanins in red-fleshed apple is 268.6 mg·kg^-1 and mainly consist of cyanidin-3-galactoside, cyanidin-3-arabinoside and cyanidin-3-glucoside, and cyanidin-3-galactoside accounts for the largest proportion of 75.34%. The wavelength of maximum absorption of red-fleshed apple anthocyanins in water system is at 515 nm, and the color and A_515mn of red-fleshed apple anthocyanins change due to different pH values. At the concentration of 0.01 mol·L^-1, caffeic acid, ferulic acid, chlorogenic acid and gallic acid all showed evident copigmentation, which led to the phenomena of hyperchromic effect and the bathochromic shift in varying degrees. Especially, ferulic acid caused the greatest extent of redshift (11nm) in anthocyanins solution. After anthocyanins was heated in water-bath at 60℃, 80℃, and 100℃ for one hour, respectively, chlorogenic acid and gallic acid showed the best protection effect, which is better than caffeic acid and ferulic acid. Under the natural lighting, the half-life of anthocyanins solution without copigments was less than 7 days, while the stabilities of anthocyanins with phenolic acids as copigments increased evidently (P＜0.05). The half-life of anthocyanins with chlorogenic acid, caffeic acid, gallic acid, and ferulic acid increased by 170.87%, 142.68%, 39.56% and 23.05%, respectively. When the concentration of H₂O₂ in anthocyanins solution was at a range of 0.1%-0.6%, anthocyanins was oxidized rapidly, but phenolic acids can protect anthocyanins from oxidation apparently. After being oxidized by 0.1% H₂O₂ for one hour, the content of anthocyanins in contrast group decreased to 38.39%, however, the retention rate of treatment groups with caffeic acid, ferulic acid, chlorogenic acid and gallic acid were 57.95%, 63.10%, 59.95% and 48.81%, respectively. The solution of Fe³⁺ with concentration of 2.5×10^-4—1×10^-3 mol·L^-1 had an adverse effect on anthocyanins color. In the solution containing Fe³⁺, the stability of anthocyanins with gallic acid as copigment was the highest. Additionally, the A_515nm of treatment groups were higher than contrast group (P＜0.05). 【Conclusion】The color of red-fleshed apple anthocyanins depends on pH value of solutions obviously. The property of anthocyanins remained stable and the color kept bright red when pH＜3.0. Caffeic acid, ferulic acid, chlorogenic acid and gallic acid showed varying degrees of hyperchromic effect and the bathochromic shift on red-fleshed apple anthocyanins and evidently improved the stability of anthocyanins (P＜0.05) under various conditions of heating, light exposure, oxidation and adding metal ion of Fe³⁺.

Drying Characteristics and Model of Bitter Melon Slice in Air-Impingement Jet Dryer

XUE Shan, ZHAO WuQi, GAO GuiTian, Wu Zhong

Scientia Agricultura Sinica. 2017, 50(4): 743-754. doi:10.3864/j.issn.0578-1752.2017.04.014

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【Objective】In order to improve the drying quality of the bitter melon slice(BMS), shorten the drying time, the effects of the air-impingement drying conditions on the drying characteristics of the BMS were studied and the drying kinetics model was established to predict the moisture change in the drying process. 【Method】The BMS were dried by the air-impingement jet dryer made by the authors’ laboratory. The effects of different air temperatures (40, 50, 60, 70 and 80℃), air velocities (9, 10, 11, 12 and 13 m·s^-1) and slice thickness (2, 3, 4, 5 and 6 mm) on the drying characteristics of materials and effective moisture diffusion coefficient of water were studied, and the activation energy was calculated. With the R², χ² and RMSE as the evaluation indexes, the optimum model was screened within the five commonly used dry models fitting the experimental data by Origin 8.0 software, then the relationships between the model parameters and drying conditions was establish and the prediction effect of the optimum drying model was verified.【Result】The air-impingement jet drying of BMS occurred in the falling rate drying period, and there was no constant drying rate stage. Under the experimental condition, air temperature, air velocities and slice thickness all had a certain effect on dry characteristics of BMS in air-impingement jet drying process. With the increase of air temperature and air velocities, the decrease of the slice thickness, the moisture of material decreased more fast and the drying rate was rising, the drying time was short, but the influence of air velocities was less significant than air temperature and slice thickness. The water effective diffusion coefficient of the BMS during drying process could be calculated by Fick’s second law, and it increased with the increase of air temperature, air velocities and slice thickness. The maximum effective diffusion coefficient was 2.9668×10^-9 m²·s^-1. Arrhenius was used to calculate the activation energy of BMS in drying process and the value of E_a was 29.89 kJ·mol^-1. The five selected models all had good fitness (R²>0.98), they could predict the moisture change of the BMS in air-impingement jet drying process. Of the five models, the Two term exponential model had the highest coefficient of determination R² (0.99937), the lowest chi-square χ² (0.00876) and root mean square RMSE (0.000077), and it is the optimum model of the BMS in air-impingement jet drying. 【Conclusion】All the factors including the air temperature, air velocities and slice thickness had influence on the drying curve, the drying rate curve and moisture effective diffusion coefficient, and their influences were in an order of the air temperature＞air velocities＞slice thickness. Two term exponential model could properly describe the air-impingement jet drying behavior of BMS and could be used to predict the moisture change of the BMS in air-impingement jet drying process under the condition that the air temperatures between 40 and 80℃, air velocities between 9 and 13 m·s^-1 and slice thickness between 2 and 6 mm.

Genome-Wide Association Study on Mastitis Resistance Based on Somatic Cell Scores in Chinese Holstein Cows

WANG Xiao, ZHANG Qin, YU Ying

Scientia Agricultura Sinica. 2017, 50(4): 755-763. doi:10.3864/j.issn.0578-1752.2017.04.015

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【Objective】In order to conduct maker assisted selection, the aim of this study is to find molecular markers related to mastitis resistance by identifying and screening relevant genes through genome-wide association study.【Method】A total of 2093 Chinese Holsteins SCC in Beijing region were log-transformed to LASCS and SCS-SD which were following normal distribution

according to formula LASCS=log₂ and SCS-SD=log₂ . LASCS and SCS-SD were divided into two groups

including mastitis susceptive cows (Case) and resistant cows (Control) based on half of standard deviation (0.5 SD) and one standard deviation (1 SD) of LASCS and SCS-SD. The unqualified SNPs were deleted after quality control for 54 001 SNPs by the criteria: call rate < 90 %, SNPs deviated extremely from Hardy-Weinberg equilibrium (P < 10E−6) and minor allele frequency < 0.03. Case-control association testing for LASCS and SCS-SD were further performed by ROASTRIPS software (version 1.2) which contains 3 tests: RM test, RCHI test and RW test. Bonferroni multiple testing was adopted to adjust the results of association analysis on each chromosome level. The number of SNPs on each chromosome divided by 0.05 was considered as the significant chromosome level. At the same time, LASCS and SCS-SD of all the individuals were considered as the continual traits for association analysis by using linear mixed model method. The results were further confirmed after comparing to case-control method.【Result】For the divided population by 0.5 SD and 1 SD, a total of 1371 and 708 individuals were used for LASCS association analysis as well as 1385 and 716 individuals used for SCS-SD association analysis, respectively. After quality control by deleting unqualified SNPs, a total of 43781/43671 (43817/43704) SNPs were available for 0.5 SD/1 SD of LASCS (SCS-SD), respectively. Through Bonferroni correction at chromosome level (P < 0.05) after association analysis, 5 SNPs were detected significantly including 3 SNPs located at chromosome X and 2 other SNPs located on chromosomes 7 and 28, separately. One genome-level significant SNP (Hapmap48573-BTA-104531) was identified on chromosome X for 0.5 SD of SCS-SD by RCHI test (P = 1.14E-06). The results showed that the significant SNPs (Hapmap48573-BTA-104531 and Hapmap54175-rs29021817) on chromosome X were located in gene IL1RAPL2 and the significant SNP on chromosome 7 was close to ILF3 gene which is related to inflammation response. These two genes (IL1RAPL2 and ILF3) are relevant to interleukins while interleukins 4, 5, 6, 12, 13, 17, 22, and 23 play an important role when participating in different inflammation responses. The function of ILF3 gene is a translation inhibitory protein as a member of interleukins. The current study also used linear mixed model to perform association analysis on LASCS and SCS-SD, and identified the same SNP (BTA-28466-no-rs) on chromosome X detected by case-control method. Compared to two methods (Linear mixed model method and case-control method), the same SNPs could be found by two methods for the same traits while association results were various for different traits.【Conclusion】The results of the study have found the genes related to inflammation response of mammary gland which provide fundamental data for molecular genetic basis of mastitis resistance in dairy cattle.

The Influences of Over-Expression of Oct-1 on Major Genes of Coat Color in Melanocytes of Mice

YANG YuJing, NIE RuiQiang, XIE JianShan, FAN RuiWen, XU DongMei, DONG ChangSheng

Scientia Agricultura Sinica. 2017, 50(4): 764-773. doi:10.3864/j.issn.0578-1752.2017.04.016

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【Objective】The aim of the study was to clone the octamer-binding transcription factor 1, to investigate whether over-expression of Oct-1 regulated the major genes of coat color in melanocytes of mouse at the transcriptional levels and to explore its influence on the formation of melanin. 【Method】 The CDS region in Oct-1 gene were cloned from melanocytes of mouse by primers and PCR to build a mouse Oct-1 cloning vector and eukaryotic expression vector. The KEGG PATHWAY, NCBI, and Transfec softwares were adopted to analyze the biological information of the obtained sequence. Over-expression of Oct-1 was conducted in the melanocytes of the 5^th generation mouse through the cell transfection technique and transfer efficiency was observed by fluorescence microscope. The content of melanin in melanocytes was detected by spectrophotometer. The level of major genes were detected using real-time PCR and the proteins of MITF，TYR，TYRP-1 and TYRP-2 were detected using western blot.【Result】Results showed that the 2 313 bp cDNA sequence of Oct-1 gene was obtained by sequencing and splicing. Eukaryotic expression vector was successfully constructed with specific TYRP-2 gene promoter of mouse and a startup report gene of green fluorescent protein. KEGG PATHWAY analysis obtained 34 candidate genes related with coat color，and the promoters of these 34 candidate genes were found by NCBI. The major gene of coat color regulated by Oct 1 was determined by using Transfec software. Under the fluorescence microscope, green fluorescence could be identified in melanocytes of mouse. The contents of melanin in melanocytes were reduced (P＜0.05). Real-time PCR results showed that Oct-1 mRNA was significantly increased (P＜0.001),witch indicated Oct-1 high transfection efficiency. MITF mRNA was significantly reduced to 0.70 times (P＜0.01) and TCF mRNA was significantly reduced to 0.66 times (P＜0.01). The expressions of Ras, Frizzled, ERK2 and TYRP-2 mRNA did not change. TYR mRNA was significantly increased to 7.69 times (P＜0.01), TYRP-1 mRNA was significantly increased to 3.11 times (P＜0.01), αMSH mRNA was significantly increased to 18.49 times (P＜0.001), AC mRNA was significantly increased to 6.88 times (P＜0.01), c-kit mRNA was significantly increased to 18.75 times (P＜0.001), ET1 mRNA was increased to 1.50 times (P＜0.05), ETB-R mRNA was significantly increased to 13.47 times (P＜0.001), and CAM mRNA was increased to 1.46 times (P＜0.05). Western blot results showed that MITF protein was significantly reduced to 0.67 times (P＜0.01), TYR protein was increased to 1.16 times (P＜0.05), TYRP-1 protein was increased to 1.15 times (P＜0.05) and TYRP-2 protein did not change.【Conclusion】The 2 313 bp length CDS region of mouse Oct-1 gene was got by PCR, TA cloning and nucleic acid sequencing technology. Major gene of coat color regulated by Oct 1 was determined by bioinformatics analysis. Results of the study suggested that after over-expression of Oct-1, the expression of MITF and TCF was reduced, while that of TYR, TYRP-1, αMSH, AC, c-kit, ET1, ETB-R and CAM was increased. Therefore, the Oct-1 may mediate the alteration of coat color through regulating genes involved in the formation process of coat color.

Comparison of Healing Ability on Potato Tuber Cultivars ‘Qingshu No. 168’ and ‘Longshu No. 3’

JIANG Hong, BI Yang, LI ChangJian, WANG Yi, LI ShengE, LIU YaoNa, WANG Bin

Scientia Agricultura Sinica. 2017, 50(4): 774-782. doi:10.3864/j.issn.0578-1752.2017.04.017

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【Objective】The objective of this study is to find out the differences of tuber healing ability of resistant and susceptible potato cultivars against dry rot (‘Qingshu No. 168’ and ‘Longshu No. 3’), and explore the reasons causing differences in the levels of lignin and suberin accumulation and phenylpropanoid metabolism.【Method】The resistant cultivar ‘Qingshu No. 168’ and susceptible cultivar ‘Longshu No. 3’ were used as materials. The damage of tubers was artificially simulated and heal was conducted at ambient temperature. The healing effect was assessed by determining the weight loss and disease index of wounded tubers that were inoculated with Fusarium sulphureum at every healing time point. Phloroglucinol-HCl staining and toluidin blue O-neutral red staining were used to observe lignin and suberin deposition, and the lignified cell layers and suberin fluorescent intensity were quantified. Moreover, the key enzyme and metabolites of phenylpropanoid metabolism pathway such as phenylalanine ammonia lyase activity, and the contents of lignin, total phenol and flavonoid were determined to compare the differences of healing ability between the two cultivars.【Result】The weight loss of ‘Qingshu No. 168’ was significantly lower than that of ‘Longshu No. 3’ during healing. The weight loss of ‘Qingshu No. 168’ and ‘Longshu No. 3’ was 0.93% and 1.96% after 14 days of healing, and the weight loss of ‘Qingshu No. 168’ was 52.3% lower than that of ‘Longshu No. 3’. The disease index of ‘Qingshu No. 168’ was also significantly lower than ‘Longshu No. 3’ after inoculated with F. sulphureum during healing. After 3 days of healing for inoculated tubers, the disease index of ‘Qingshu No. 168’ and ‘Longshu No. 3’ was 20.36 and 71.59, respectively, the former was 71.5% lower than the later. During healing, ‘Qingshu No. 168’ had higher accumulation rate of lignin and suberin than ‘Longshu No. 3’. After healing for 14 days, the thickness of lignified cell layers and total fluorescent intensity of suberin of ‘Qingshu No. 168’ were 47.4% and 60.6% higher than ‘Longshu No. 3’. In addition, ‘Qingshu No. 168’ showed more phenylpropanoid metabolism activity than ‘Longshu No. 3’. The activity of phenylalanine ammonialyase and the lignin content of ‘Qingshu No. 168’ were 77% and 65% higher than ‘Longshu No. 3’after healing for 14 days, respectively. The total phenolics contents of the two cultivars showed a significant difference at late stage of healing, ‘Qingshu No. 168’ was 76% higher than ‘Longshu No. 3’ after healing for 14 days. However, no significant difference was found in the flavonoids content between the two cultivars during healing.【Conclusion】The resistant cultivar ‘Qingshu No. 168’ showed stronger healing ability than susceptible cultivar ‘Longshu No. 3’. A stronger healing ability of resistant cultivar is related with its higher phenylpropanoid metabolism activity.

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