昆虫的气味受体（Odorant receprot，OR）是它们探测和识别与其生存密切相关的外部化学线索的关键。昆虫识别配体的特异性受体与一个广泛存在的气味受体共受体（Odorant receptor coreceptor，Orco）构成了异聚体复合体。本研究运用CRISPR/Cas9基因敲除技术对我国重大入侵害虫草地贪夜蛾的Orco基因进行了敲除，并揭示了该基因在气味受体调控的嗅觉行为中的重要作用。触角电位结果表明，Orco基因敲除之后，雌雄成虫对8种测试的植物挥发物和两种性信息素的电生理反应均丧失。然而，Orco基因对雌雄成虫交配行为的影响却存在明显的差异：雄虫Orco突变体的交配行为完全被干扰而雌虫Orco突变体的交配行为却不受影响。产卵实验结果表明，Orco突变体雌虫的产卵量比野生型雌虫的产卵量减少了24.1%。总之，这些结果表明了Orco是一个干扰草地贪夜蛾正常行为的优良靶标，并为害虫的防治提供了一种可行的方法。

木质素代谢在植物对病原菌的防御中起着关键作用，并且在抵御病原菌侵染的过程中总是起到正向作用。因此，解析植物木质素响应病原菌代谢相关抗性基因的遗传机理具有重要意义。本研究以8个陆地棉品系为材料，构建了一个多亲本高世代杂交(MAGIC)群体(n=280)，该群体表现出控制优良性状的等位基因的聚合特征。为了研究木质素对黄萎病的响应(LRVW)，本研究在4种环境下分别建立了人工病圃(ADN)和轮作苗圃(RN)。通过采集和测定棉秆的木质素含量，并将不同环境下ADN/RN木素比值作为LRVW值，结果表明，群体LRVW值表现出较丰富的变异。利用63K芯片获得了9323个高质量单核苷酸多态(SNP)标记，用于MAGIC群体的基因分型，结果显示，SNPs分布于全基因组，平均密度为4.78SNP/Mb，在染色体间的分布范围为1.14 SNP/Mb (ChrA06)~10.08 SNP/Mb (ChrD08)。利用混合线性模型(MLM)对LRVW进行全基因组关联分析，并在两个以上的环境中共同检测到3个稳定的QTL，即qLRVW-A04、qLRVW-A10和qLRVW-D05。结合分析候选基因编码序列变异、诱导表达模式和功能注释，最终在QTL区间选择了两个关键候选基因Ghi_D05G01046和Ghi_D05G01221。这两个基因在编码区都出现了非同义突变，并且都受黄萎病菌强烈诱导。Ghi_D05G01046编码一个富含亮氨酸的延伸素(LRx)蛋白，与拟南芥细胞壁的生物合成和结构有关。Ghi_D05G01221编码Jaz的转录抑制因子，它在茉莉酸(JA)信号通路中发挥作用。综上所述，本研究不仅为陆地棉抗黄萎病育种和QTL定位创造了宝贵的遗传资源，也为解析陆地棉抗黄萎病的遗传基础开辟了新的视角。

本研究旨在利用拉曼光谱学方法鉴别花生油产地，并建立稳健的鉴别模型，进一步筛选出与产地密切相关的特征光谱。对来自不同省份和同一省份不同城市的159个花生油样品进行拉曼光谱测定，获得的数据进行了逐步线性判别分析分析(SLDA)，k-最近邻分析(k-NN)和多因素方差分析等。结果表明，基于全光谱的样本识别率达到90%以上。花生油的产地、品种及其互作对拉曼光谱影响显著，筛选出1400-1500 cm^-1和1600-1700 cm^-1为受品种影响较小的产地特征光谱。结合产地特征光谱建立的SLDA最佳分类模型能够快速、准确地识别花生油的产地。

本研究的目的是利用我们在先前研究中构建的F₁杂交群体的高密度遗传连锁图谱定位与春季再生相关的数量性状位点（quantitative trait loci, QTL）。该群体包含392个子代，且亲本在春季再生性状上表现出明显的差异。在两个地点连续统计了两年的表型数据，并利用IciMapping软件进行QTL定位分析。利用单个环境中表型的平均值和最佳线性无偏预测（Best Linear Unbiased Prediction，BLUP）作为QTL定位的表型，总共鉴定到36个与春季再生性状显著关联的加性QTL。其中，有十个QTL分别解释了超过10％的表型变异（phenotypic variation, PVE），在P1亲本（父本）中有四个，P2亲本（母本）中有六个。在这些加性QTL中共有六个重叠的QTL区间，在P1和P2中分别有两个和四个。在P1中，两个重叠的区间都位于连锁群7D上。在P2中，PVE >10％的四个QTL在连锁群6D上定位到相同区间。此外，在P2中鉴定出六对显著的上位性QTL，而在P1中没有定位到上位性QTL。在四个重叠的QTL（qCP2019-8，qLF2019-5，qLF2020-4和qBLUP-3）所处区间内筛选到一个候选基因，该基因被注释为MAIL1，拟南芥中的同源基因在植株的生长中起重要作用。本研究定位到的QTLs是利用标记辅助选择对紫花苜蓿春季再生性状进行遗传改良的宝贵资源，鉴定的相关基因为深入了解紫花苜蓿春季再生的遗传特性提供依据。

相对其它作物，玉米生产虽然需要较高的温度，但35℃以上高温不利于玉米产量的形成。在华北平原地区，≥35℃ 的温度在夏玉米营养生长和生殖生长并进阶段普遍发生，并对玉米产量的形成造成不可逆的伤害。因此，本文研究了9叶期至抽雄期增温对夏玉米产量形成过程的影响。结果表明，持续增温导致了花丝的伸长速率和活力下降、开花吐丝间隔期增加、果穗顶端穗粒数减少，最终影响了产量。尽管抽雄前持续增温破坏了雄花序中花药的结构，花粉活力因此降低，散粉推迟和散粉时间缩短。但是，从表型、生理层面分析，此时期的持续增温可能对雌穗的生长发育影响更加显著。总之，在玉米营养生长和生殖生长并进阶段，持续增温导致雌雄穗生长受阻，最终引起果穗秃尖和产量的大幅度降低。

Alfalfa (Medicago sativa L.) is an important forage crop and is also a target of many fungal diseases including Fusarium spp.  As of today, very little information is available about molecular mechanisms that contribute to pathogenesis and defense responses in alfalfa against Fusarium spp. and specifically against Fusarium proliferatum, the causal agent of alfalfa root rot.  In this study, we used a proteomic approach to identify inducible proteins in alfalfa during a compatible interaction with F. proliferatum strain YQC-L1.  Samples used for the two-dimensional gel electrophoresis (2-DE) and MALDI-TOF/TOF mass spectrometry were from roots and leaves of alfalfa cultivar AmeriGraze 401+Z and WL656HQ.  Plants were grown in hydroponic conditions and at 4 days post inoculation with YQC-L1.  Our disease symptom assays indicated that AmeriGraze 401+Z  was tolerant to YQC-L1 infection while WL656HQ was highly susceptible.  Analysis of differentially expressed proteins found in the 2-DE was further characterized using the MASCOT MS/MS ion search software and associated databases to identify multiple proteins that might be involved in F. proliferatum resistance.  A total of 66 and 27 differentially expressed proteins were found in the roots and leaves of the plants inoculated with YQC-L1, respectively.  These identified proteins were placed in various categories including defense and stress response related metabolism, photosynthesis and protein synthesis.  Thirteen identified proteins were validated for their expressions by quantitative reverse transcription (qRT)-PCR.  Our results suggested that some of the identified proteins might play important roles in alfalfa resistance against Fusarium spp.  These finding could facilitate further dissections of molecular mechanisms controlling root rot disease in alfalfa and potentially other legume crops.   

Increased food demand from the rapidly growing human population has caused intensive land transition from desert to farmland in arid regions of northwest China. In this developing ecosystem, the optimized fertilization strategies are becoming an urgent need for sustainable crop productivity, efficient resources use, together with the delivery of ecosystems services including soil carbon (C) and nitrogen (N) accumulation. Through a 7-year field experiment with 9 fertilization treatments in a newly cultivated farmland, we tested whether different fertilizations had significant influences on soil C and N accumulation in this developing ecosystem, and also investigated possible mechanisms for this influence. The results showed that applying organic manure in cultivated farmland significantly increased the soil C and N accumulation rates; this influence was greater when it was combined with chemical fertilizer, accumulating 2.01 t C and 0.11 t N ha–1 yr–1 in the most successful fertilization treatment. These high rates of C and N accumulation were found associated with increased input of C and N, although the relationship between the N accumulation rate and N input was not significant. The improved soil physical properties was observed under only organic manure and integrated fertilization treatments, and the significant relationship between soil C or N and soil physical properties were also found in this study. The results suggest that in newly cultivated farmland, long term organic manure and integrated fertilization can yield significant benefits for soil C and N accumulation, and deliver additional influence on physical properties.

    Alfalfa is widely grown and is one of the most important forage crops in the world, but its growth and biomass production are markedly reduced under salt and drought stress, particularly during the early seedling stage. To identify the mechanisms behind salt and drought responsiveness at the alfalfa seedling stage, the proteins expressed were analyzed under no-treatment, 200 mol L^–1 NaCl and 180 g L^–1 PEG treatment conditions during the seedling stage. Out of more than 800 protein spots detected on two-dimensional electrophoresis (2-DE) gels, 35 proteins showed statistically significant responses (P<0.05) to NaCl and PEG stress, which were selected for tandem mass spectrometric identification, owing to their good resolution and abundance levels, and 32 proteins were positively identified. The identified proteins were divided into seven functional categories: photosynthetic metabolism, protein biosynthesis, folding and assembly, carbohydrate metabolism-associated proteins, stress defense related protein, metabolism of nucleic acid, other function categories and unknown proteins. Our results suggested that these proteins may play roles in alfalfa adaptation to salt and drought stress. Further study of these proteins will provide insights into the molecular mechanisms of abiotic stress and the discovery of new candidate markers in alfalfa.

Cultivar selection is important for alfalfa (Medicago sativa L.) hay production. From 2009 to 2012, a field study was conducted to evaluate the dry matter yield (DMY) of 28 cultivars in Cangzhou District of Hebei province, China, and to determine the most suitable cultivars for this province and other zones with similar climate conditions. 28 alfalfa cultivars were sown in late March of 2009 and were harvested for hay four times in each subsequent year. The results showed that the climatic conditions resulted in significant differences in annual DMY among years, with the second year being the highest and the first year the lowest. The top five cultivars with the highest total DMY were L2750 (62.75 t ha-1), Horn (62.72 t ha-1), 86-266 (61.55 t ha-1), German (61.44 t ha-1) and Zhongmu 1 (61.18 t ha-1), respectively. Across all four years, first harvest had the highest ratios to annual DMY except the cultivar of Rambler, while the fourth harvest had the lowest ratio. There were positive correlation relationships between DMY of each harvest and annual DMY, and the correlation coefficients were all significant in four years. And the path coefficients of first harvest were always the highest in four years. The qualities showed small variations among these cultivars and the cultivar L3750 presented the highest crude protein in both years. Crude protein had significant positive correlation with relative feed value (RFV) in both years while crude fiber had significant negative correlation with RFV and crude fiber.

Soybean mosaic virus (SMV), a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. As the P3 gene is thought to be involved in viral replication, systemic infection, pathogenicity, and overcoming resistance, knowledge of the P3 gene sequences of SMV and other potyviruses would be useful in efforts to know the genetic relationships among them and control the disease. P3 gene sequences were obtained from representative isolates of the above-mentioned 16 SMV strains and were compared with other SMV strains and 16 Potyvirus species from the National Center for Biotechnology GenBank database. The P3 genes from the 16 SMV isolates are composed of 1 041 nucleotides, encoding 347 amino acids, and share 90.7-100% nucleotide (NT) sequence identities and 95.1-100% amino acid (AA) sequence identities. The P3 coding regions of the 16 SMV isolates share high identities (92.4-98.9% NT and 96.0-100% AA) with the reported Korean isolates, followed by the USA isolates (88.5-97.9% NT and 91.4-98.6% AA), and share low identities (80.5-85.2% NT and 82.1-84.7% AA) with the reported HZ1 and P isolates from Pinellia ternata. The sequence identities of the P3 genes between SMV and the 16 potyviruses varied from 44.4 to 81.9% in the NT sequences and from 21.4 to 85.3% in the AA sequences, respectively. Among them, SMV was closely related to Watermelon mosaic virus (WMV), with 76.0-81.9% NT and 77.5-85.3% AA identities. In addition, the SMV isolates and potyvirus species were clustered into six distinct groups. All the SMV strains isolated from soybean were clustered in Group I, and the remaining species were clustered in other groups. A multiple sequence alignment analysis of the C-terminal regions indicated that the P3 genes within a species were highly conserved, whereas those among species were relatively variable.

Phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) catalyses phosphoenolpyruvate (PEP) to yield oxaloacetate, which is involved in protein biosynthesis. Pyruvate kinase (PK; EC 2.7.1.40) catalyzes PEP to yield pyruvate, which is involved in fatty acid synthesis. In this study, five PEPC genes (AhPEPC1, AhPEPC2, AhPEPC3, AhPEPC4, and AhPEPC5) from peanut have been cloned. Using a quantitative real-time RT-PCR approach, the expression pattern of each gene was monitored during the seed development of four peanut varieties (E11, Hebeigaoyou, Naihan 1, and Huayu 26). It was found that these five genes shared similar expression behaviors over the developmental stages of E11 with high expression levels at 30 and 40 d after pegging (DAP); whereas these five genes showed irregular expression patterns during the seed development of Hebeigaoyou. In Naihan 1 and Huayu 26, the expression levels of the five genes remained relatively high in the first stage. The PEPC activity was monitored during the seed development of four peanut varieties and seed oil content was also characterized during whole period of seed development. The PEPC activity followed the oil accumulation pattern during the early stages of development but they showed a significantly negative correlation thereafter. These results suggested that PEPC may play an important role in lipid accumulation during the seed development of four peanut varieties tested.