土壤调理剂中添加硅和有机肥可抑制重金属离子从土壤向作物的转移，但目前并不清楚硅和有机肥如何通过影响土壤性质和微生态环境进而减少水稻的镉积累。本研究通过两地田间实验分析了含硅和有机肥的L型土壤调理剂对细菌和真菌群落多样性、土壤pH、有机质及有效硅含量的影响。结果表明，随着土壤调理剂中硅和有机肥含量的增加，两个试验点的水稻产量分别增加了16.8%~25.8%和6.8%~13.1%, 稻米Cd含量显著降低了8.2%~21.1%和10.8%~40.6%。土壤微生物组学分析证明与镉吸附、螯合相关的Firmicutes和Actinobacteriota细菌和与大分子物质降解有关的Basidiomycota真菌种群丰度的增加，有利于抑制土壤中镉的活性（土壤ESC-Cd降低了14.4%~14.8%和18.1%~20.6%），这与施用土壤调理剂引起有机质和有效硅含量增加有关。总之，L型土壤调理剂中的有机质和硅可通过调节土壤中镉钝化优势菌群，降低土壤镉有效性，最终减少稻米镉积累。

型干扰素（type I interferon, IFN-I）是保护机体抵御病原微生物感染的重要防线。干扰素调节因子（IFN regulatory factor，IRF）在DNA及RNA病毒感染鸡后刺激机体产生IFN-I、建立抗感染免疫的过程中发挥重要作用。在哺乳动物体内，主要依赖IRF3和IRF7共同调节IFN-I的表达。但是，鸡先天缺乏IRF3，主要依赖IRF7调控IFN-I的表达。目前，已在哺乳动物体内鉴定出4种IRF7剪切异构体，但鸡IRF7（chicken IRF7， chIRF7）是否存在类似的剪切变异及其功能均不清楚。本研究在构建chIRF7克隆过程中，鉴定出一个新的剪切异构体，命名为chIRF7-iso。序列分析发现，与chIRF7相比，chIRF7-iso包含完整的N端DNA-结合结构域，但其C端存在14个差异氨基酸。随后，我们评估了chIRF7和chIRF7-iso对IFN-β启动子的活化能力，并以新城疫病毒弱毒疫苗株LaSota和高致病性血清4型禽腺病毒（Fowl adenovirus serotype 4, FAdV-4）作为研究对象，评估了chIRF7-iso对这两株病毒在鸡肝细胞（leghorn male hepatocellular， LMH）中复制能力的影响。结果发现，chIRF7可以促进IFN-β的高水平表达，而chIRF7-iso对IFN-β启动子活性及表达量无明显影响。此外，LaSota和FAdV-4在过表达chIRF7的LMH细胞中复制水平较低，而在chIRF7-iso转染组细胞中增殖较好。这些结果均说明，本研究新鉴定出一种chIRF7剪切异构体，且chIRF7-iso可能通过负调控IFN-β通路而影响病毒的增殖。该研究为丰富鸡天然免疫应答奠定了基础。

H9N2禽流感病毒（AIV）已在全球家禽中广泛流行，并在人类和哺乳动物中引起零星的感染。本研究旨在了解H9N2AIV的遗传进化和流行病学特征。2019-2021年，从中国山东省采集136份疑似AI感染的鸡的组织样品，共分离出11株H9N2AIV。遗传进化分析表明，分离出的11株H9N2AIV的8个基因片段与欧亚谱系的几个亚谱系密切相关：BJ/94-like分支（HA和NA基因）、G1-like分支（PB2和M基因）、SH/F/98-like分支（PB1、PA、NP和NS基因）。所有分离病毒HA蛋白的裂解位点仅含有一个碱性氨基酸，表明它们都属于低致病性AIV。分离株表现出优先与类人受体 (HA) 结合和哺乳动物适应性（PB2、PB1和PA）的突变位点，从而增加了它们跨越物种屏障并引起人类感染的风险。此外，11株H9N2AIV还存在抗原位点和耐药性位点的突变，说明应及时评估疫苗的有效性，加强抗流感药物的研发。小鼠感染显示，4株H9N2AIV的致病性水平不同。从中国山东省采集的7237份鸡血清样品中，HI抗体平均滴度为8.49 log₂，离散度为23.56%，抗体合格率为98.52%（≥4 1og2），表明山东省规模化养鸡场对H9N2AI的整体免疫效果较好。基于我们的结果，应该加强对H9N2AIV的流行病学监测。

建立一种同时鉴别诊断猪瘟病毒（classical swine fever virus, CSFV)、非洲猪瘟病毒（African swine fever virus, ASF）和猪非典型瘟病毒（atypical porcine pestivirus, APPV）的快速、灵敏、有效的检测方法。依据GenBank中登录的CSFV (5¢ UTR)、ASFV (B646L) 和 APPV (5¢ UTR) 的高度保守基因序列分别设计和优化了多对特异性引物和Taq-man探针，以保守区基因序列分别制备三种阳性质粒，用矩阵法优化单重/多重荧光PCR的反应体系和条件，为避免荧光通道的交叉干扰多重荧光PCR扩增，结合所标记的荧光报告基团做颜色补偿试验，构建标准曲线的扩增图和对应的线性方程，并进行特异性、敏感性、重复性、符合性以及临床样本的检测等试验。三种病毒的标准曲线相关系数均达到0.995以上，具有良好的线性关系；与其它常见猪病无交叉扩增反应，具有很好的特异性；多重荧光PCR的最低检测量均为1 copy/mL，具有较高的敏感性；组内和组间的变异系数均小于1%，具有很好的重复性。该方法与CSF的国标(GB/T 27540-2011), ASF的国标 (GB/T 18648-2020)，APPV的发明专利 (CN108611442A)检测样本盘的22个毒株样本符合率为100%。本研究建立的多重荧光PCR检测方法具有快速、高效、通量高、特异性好、灵敏度高等特点，可以对CSFV、ASFV和APPV病毒进行鉴别检测，为动物疫病的流行病学调查、疫情的检测提供一种新型的检测手段。本研究结合荧光PCR仪不同荧光通道设计CSFV、ASFV和APPV探针荧光信号强度较高且干扰较小的FAM、CY5和HEX报告基团，建立多重荧光PCR检测方法，用于同时鉴别诊断3种主要猪病毒的检测方法，在临床诊断中具有重要的应用价值。

小麦是世界上主要的粮食作物之一。为满足日益增长的人口对小麦的需求的增长，实现小麦等作物的产量最大化，挖掘并阐明增产基因的功能为基因工程育种提供基础显得尤为重要。来自玉米的bHLH转录因子ABP7参与调控籽粒发育，本文通过转基因小麦，研究了ABP7对小麦产量相关性状的影响。分子鉴定结果表明，HB123 和 HB287转基因系基因组中存在多拷贝ABP7基因插入，并且其具有较高表达量，而转基因系QB205为单拷贝插入同时其表达量与野生型材料无显著差异。田间试验表型分析表明，HB123 和 HB287转基因系的穗粒数、穗粒重、千粒重、粒长和粒宽等籽粒产量相关性状以及小区产量都得到了提高，而QB205并没有在这些性状上与野生型表现出差异。此外，HB123 和 HB287转基因系的旗叶中的总叶绿素、叶绿素a和叶绿素b及总可溶性糖的含量相比于野生型材料都显著提高。总之，ABP7能够正向调控转基因小麦的籽粒相关性状并提高小区产量，可用于小麦增产育种。

叶形是影响陆地棉植株冠层结构和产量的重要农艺性状，同时还与光合效率密切相关，是棉花高光效育种研究的重点。陆地棉叶形根据叶裂深度可分为常态叶、亚鸡脚叶、鸡脚叶和超鸡脚叶，主要由D基因组L-D₁位点的等位基因调控，其对陆地棉叶片形态、冠层结构和光合产量的影响尚不清楚。本研究利用病毒诱导基因沉默技术（VIGS）及叶形参数分析发现L-D₁等位基因对叶形的调控具有基因剂量效应；打顶前，鲁棉研22亚鸡脚叶品系叶面积系数比常态叶品系分别减少8.54%和4.91%，打顶后分别减少8.48%和11.19%；中部冠层透光率打顶前后分别增加71.35%和134.88%，下部冠层透光率打顶前后分别增加123.14%和41.81%；鲁棉研28号遗传背景下，亚鸡脚叶系中部冠层透光率打顶前后分别增加38.88和93.10%，下部冠层透光率打顶前后分别增加28.15和118.62%。鲁棉研22亚鸡脚叶系净光合速率在大部分生育期内可提高0.93～12.45%，在鲁棉研28遗传背景下可提高7.12～13.84%。在两种遗传背景下，亚鸡脚叶品系的最终生物量比常态叶对照分别增加9.43和19.35%，产量也分别增加8.6和7.05%，且同时对纤维品质无不良影响。

增加种植密度是提高玉米产量的一种有效途径。然而，高种植密度严重影响玉米生长发育，空秆则是限制粮食产量的重要因素之一。本研究中，我们对280份玉米自交系开展了多年田间耐密性鉴定，调查了正常密度（67500株/公顷）和高密度（120000株/公顷）种植条件下的空杆率。基于控制群体结构和相对亲缘关系（Q+K）的混合线性模型，利用776254个SNP标记进行全基因组关联分析（GWAS）。结果发现，共有20个SNP与正常密度和高密度下的空秆率相关，落于9个基因内，其中4个SNP在正常密度和高密度下均可被关联到；13个与空秆率比值（高密度/正常密度）相关的SNP，位于7个基因内。此外，代谢通路预测结果显示，谷氨酸和精氨酸等氨基酸代谢通路和MAPK信号通路可能在玉米密植中发挥重要作用。本研究结果为高密度种植下玉米耐受性的遗传基础提供了新的见解，有助于促进高产玉米育种。

Cold stress is a major problem in rice production.  To rapidly identify genes for cold tolerance in Dongxiang wild rice (DWR, Oryza rufipogon Griff.), sequencing-based bulked segregant analysis of QTL-seq method was used to resequence the extremely resistant (R) and susceptible (S) bulks of a backcross inbred lines (BILs) population (derived from Oryza sativa×O. rufipogon) and their parents.  Single nucleotide polymorphisms (SNP)-index graphs and corresponding Δ(SNP-index) graphs (at 99 and 95% confidence levels) for R- and S-bulks detected a total of 2 609 candidate SNPs, including 58 candidate cold-tolerance genes.  Quantitative real-time PCR analysis revealed that 5 out of the 58 candidate genes had significant differences in expression between O. sativa and O. rufipogon.  Structural variation and functional annotations of the 5 candidate genes were also analyzed, and allowed us to identify 2 insertion-deletion (InDel) markers (12-7 and 12-16) that were linked with candidate genes on chromosome 12 in DWR.  These results are helpful for cloning and using cold tolerance genes from common wild rice in cultivated rice.

    Cold stress is one of the major restraints for rice production. Cold tolerance is controlled by complex genetic factor. In this study, a backcross inbred lines (BILs) population derived from an inter-specific cross (Oryza sativa L.×O. rufipogon Griff.) was used for genetic linkage map construction and quantitative trait locus (QTL) mapping. A linkage map consisting of 153 markers was constructed, spanning 1 596.8 cM with an average distance of 11.32 cM between the adjacent markers. Phenotypic evaluation of the parents and BILs under (6±1)°C cold stress revealed that the ability of cold tolerance in BILs at early seedling obeyed a skewed normal and continuous distribution. Fifteen QTLs on chromosomes 6, 7, 8, 11, and 12 were identified using survival percent (SP) and non death percent (NDP) as indicators of cold tolerance, which could explain 5.99 to 40.07% of the phenotypic variance, of which the LOD values ranged from 3.04 to 11.32. Four QTLs on chromosomes 3, 5 and 7 were detected using leaf conductivity (LC) and root conductivity (RC) as indicators of cold tolerance, ranging from 19.54 to 33.53% for the phenotypic variance explained and 2.54 to 6.12 for the LOD values. These results suggested that there might be multi major QTLs in O. rufipogon and some useful genes for cold tolerance have been transferred into cultivated rice, which would be helpful for cloning and utilizing the cold tolerance-responsive genes from wild rice.

To improve Mixograph testing effect, Farinograph measurements were adopted as a quality standard and changes in water absorption and parameter conversion in Mixograph test were explored. Comparative study showed that increasing water absorption to about 73% and converting original parameters to compound parameters in Mixograph tests significantly increased their predictive power for flour quality. These efforts also enabled the adoption of fixed water addition level in Mixograph test and simplified the test procedure significantly. With the success in parameter conversions, Mixograph test results were successfully described by Farinograph parameters, which allow breeders to compare and exchange test results easily. All these changes optimized the official method of Mixograph test with simplified procedure and enhanced reliability and made the Mixograph being the superior tool for quality assessment in wheat-breeding programs.

Proper application of nitrogen (N) fertilizers and irrigation management are important production practices that can reduce nitrate leaching into groundwater and improve the N use efficiency (NUE). A lysimeter/rain shelter facility was used to study effects of the rate of N fertilization, type of N fertilizer, and irrigation level on key aspects of winter wheat production over three growing seasons (response variables were nitrate transport, N leaching, and NUE). Results indicated that nitrate concentration in the soil profile and N leaching increased with the rate of N fertilization. At the end of the third season, nitrate concentration in the top 0–75 cm layer of soil was higher with manure treatment while urea treatments resulted in higher concentrations in the 100–200 cm layer. With normal irrigation, 3.4 to 15.3% of N from applied fertilizer was leached from the soil, yet no leaching occurred under a stress irrigation treatment. The manure treatment experienced less N leaching than the urea treatment in all cases except for the 180 kg N ha-1 rate in 2011–2012 (season 3). In terms of grain yield (GY), dry matter (DM) or NUE parameters, values for the manure treatment were lower than for the urea treatment in 2009–2010 (season 1), yet were otherwise higher for urea treatment in season 3. GY and crop nitrogen uptake (NU) were elevated when the rate of N fertilizer increased, while the NUE decreased; GY, DM, and NU increased with the amount of irrigation. Data indicated that reduced rates of N fertilization combined with increased manure application and proper irrigation management can lower nitrate levels in the subsoil and reduce potential N leaching into groundwater.

Water shortage is a serious issue threatening the sustainable development of agriculture in the North China Plain, with the winter wheat (Triticum aestivum L.) as its largest water-consuming crop. The effects of tillage practices on the water consumption and water use efficiency (WUE) of wheat under high-yield conditions using supplemental irrigation based on testing soil moisture dynamic change were examined in this study. This experiment was conducted from 2007 to 2010, with five tillage practice treatments, namely, strip rotary tillage (SR), strip rotary tillage after subsoiling (SRS), rotary tillage (R), rotary tillage after subsoiling (RS), and plowing tillage (P). The results showed that in the SRS and RS treatments the total water and soil water consumptions were 11.81, 25.18% and 12.16, 14.75% higher than those in SR and R treatments, respectively. The lowest ratio of irrigation consumption to total water consumption in the SRS treatment was 18.53 and 21.88% for the 2008-2009 and 2009- 2010 growing seasons, respectively. However, the highest percentage of water consumption was found in the SRS treatment from anthesis to maturity. No significant difference was found between the WUE of the flag leaf at the later filling stage in the SRS and RS treatments, but the flag leaf WUE at these stages were higher than those of other treatments. The SRS and RS treatments exhibited the highest grain yield (9 573.76 and 9 507.49 kg ha-1 for 3-yr average) with no significant difference between the two treatments, followed by P, R and SR treatments. But the SRS treatment had the highest WUE. Thus, the 1-yr subsoiling tillage, plus 2 yr of strip rotary planting operation may be an efficient measure to increase wheat yield and WUE.