红皮梨因鲜艳的果皮色泽受消费者喜爱，对其果皮花青苷生物合成分子调控机制已有较多的研究；而红肉梨仅存在于少数西洋梨中，目前对红肉梨中花青苷合成的分子调控机制知之甚少。本研究基于红肉与白肉西洋梨的转录组比较分析，鉴定到一个在果肉中表达趋势与花青苷含量变化显著相关的乙烯响应因子PcERF5。进一步通过瞬时转化梨果皮和稳定转化苹果愈伤组织，验证了候选基因PcERF5调控花青苷生物合成的功能。研究表明，PcERF5可通过不同途径调控花青苷的生物合成。一方面，PcERF5激活了花青苷生物合成途径中结构基因(PcDFR、PcANS和PcUFGT)以及PcMYB10和PcMYB114关键转录因子的表达。另一方面，PcERF5与PcMYB10互作形成ERF5-MYB10蛋白复合体，增强了PcERF5对其靶基因的转录激活。因此，本研究揭示了PcERF5作为转录激活子促进西洋梨果肉中花青苷合成的功能，研究结果不仅为花青苷生物合成的调控机制提供了新的见解，也为红肉梨的分子育种提供了理论指导

黑麦(Secale cereale L., 2n=2x=14, RR)因具有多种病害抗性和非生物胁迫耐性受性强的特点而被认为是普通小麦改良的重要遗传资源。源自德国栽培黑麦品种Petkus的1RS染色体在小麦的育种进程中起着举足轻重的作用，但由于其所具有的抗病性逐渐变弱，因此亟需发掘新的抗性资源。本研究从普通小麦和墨西哥黑麦的杂交后代中选育了一个新型衍生后代，命名为D27。细胞学观察显示D27的核型组成为2n=42=21II。基因组原位杂交（GISH）结果表明D27中含有一对整臂易位的墨西哥黑麦染色体，该外源染色体在有丝分裂和减数分裂过程中均能稳定遗传。荧光原位杂交（FISH）和醇溶蛋白电泳分析都表明衍生系D27的小麦1DS染色体发生了丢失，取而代之的是墨西哥黑麦的1RS染色体。这一结果同样得到了小麦简单序列重复（SSR）标记、黑麦特异序列扩增区段（SCAR）标记和小麦40K SNP芯片的验证支持，即:通过分子标记和芯片检测，D27中不含有小麦1DS染色体，但是存在黑麦1RS染色体。农艺性状鉴定表明与小麦亲本相比D27的分蘖数增多，条锈病和白粉病抗性增强。面团特性分析表明，1DS染色体被1RS染色体替换后，衍生系D27的面团粘性增加，弹性变低，有利于蛋糕的制作。综上所述，细胞遗传学稳定的小麦-墨西哥黑麦T1DL·1RS易位系可作为小麦抗病和增产育种的优异新种质，同时可用于黑麦1RS染色体遗传多样性的研究。

梨果皮的红色主要是由花青苷合成积累导致，以‘巴梨’（‘Bartlett’, BL）和‘红巴梨’（‘Max Red Bartlett’, MRB）为代表的芽变品种是研究梨果皮花青苷合成积累分子机制的理想材料。虽然早前的研究已通过遗传图谱定位了‘红巴梨’果皮色泽的数量性状基因座（QTL），但是决定色泽突变的关键基因及调控机制尚不明确。因此，本研究以‘巴梨’和‘红巴梨’为研究试材，通过对其果皮组织的转录组和DNA甲基化差异比较分析，发现‘红巴梨’的PcHY5 DNA甲基化水平低于‘巴梨’，且PcHY5基因的表达量高于‘巴梨’，由此推测PcHY5 DNA甲基化水平可能与‘巴梨’和‘红巴梨’果皮颜色差异有关，并利用双荧光素酶试验证实了PcHY5不仅能激活花青苷合成相关转录因子PcMYB10和PcMYB114，也能激活花青苷合成基因PcUFGT和转运基因PcGST，说明PcHY5不仅能调控花青苷的合成，还调控了花青苷的转运。进一步，对‘巴梨’和‘红巴梨’PcHY5的关键差异甲基化位点进行了分析，发现‘红巴梨’PcHY5内含子区域的低甲基化水平与果皮红色形成显著相关，而‘巴梨’同一位点的高甲基化水平与果皮绿色显著相关。因此，基于‘巴梨’和‘红巴梨’PcHY5基因差异表达和差异甲基化，结合基因的调控功能验证，推测‘红巴梨’PcHY5 通过DNA低甲基化水平促进其自身基因表达，并调控花青苷合成和转运相关基因的表达，从而促进果皮着色。

华山新麦草(2n=2x=14, NsNs)因具有诸多优异的农艺性状被认为是对普通小麦品种改良而言具有重要价值的野生近缘种。然而，尽管多个小麦-华山新麦草衍生后代的创制为优异性状的转移提供了种质资源基础，但小麦背景中华山新麦草染色体鉴定方法的滞后限制了对这些衍生后代的研究。本研究开发了三条高效非变性荧光原位杂交（ND-FISH）探针，其中HS-TZ3和HS-TZ4能特异性地结合华山新麦草染色体端粒区域，HS-TZ5可以和染色体着丝粒区域结合。华山新麦草染色体的FISH核型图和模式图被分别构建，以便于区分衍生系中所导入华山新麦草染色体的同源群归属。具体而言，染色体1Ns和2Ns在短臂和长臂上有相反的荧光信号，3Ns、4Ns和7Ns有叠加的双色荧光信号，5Ns和6Ns仅在短臂有荧光信号，7Ns在长臂的中间区域也有荧光信号。此外，评估了在不同组合方式下利用低密度单核苷酸多态性(SNP)芯片鉴定外源导入系的效果。结果表明最佳的模式是统计分析每条染色体上SNP位点的纯合率，15K SNP芯片可以广泛应用于附加系、代换系和易位系的鉴定，而40K SNP芯片在小麦和外源染色体易位区段的鉴定中最准确。本研究提供了基于ND-FISH和SNP芯片识别小麦背景中华山新麦草染色体同源群归属的简便方法，对于小麦-华山新麦草衍生系的高效鉴别和Ns染色体的进一步利用具有重要意义。

梨早期落叶现象通常发生在夏季，已逐渐成为威胁我国南方梨产业发展的重要问题。然而，不同梨品种资源的早期落叶性状缺乏系统的评价，且调控梨早期落叶性状的基因及其潜在的分子机制尚未明确。本研究通过对155份梨种质资源的田间调查，评价其对早期落叶的抗病或感病表现。结果表明，126份梨种质资源表现出对早期落叶的感病性，其余29份梨种质资源表现出对早期落叶的抗病性，其中19份抗性种质资源属于砂梨。为鉴定与梨早期落叶相关的抗性基因，分别采集了抗病品种‘华山’与感病品种‘翠冠’的健康叶片及感病叶片，进行RNA测序和基因表达差异比较。分析结果表明，与感病品种‘翠冠’相比，有444个基因仅在抗病品种‘华山’的健康叶片与感病叶片中差异表达；GO功能富集与KEGG代谢途径富集分析结果表明，梨早期落叶与胁迫响应密切相关。进一步的基因共表达网络分析发现，WRKY、ERF转录因子与梨早期落叶抗性高度相关。本研究不仅筛选出了梨早期落叶抗性资源，也鉴定了梨早期落叶抗性响应的重要候选基因，相关结果为促进梨抗病分子机制解析及抗性品种的分子育种奠定了基础。

本研究以‘矮玉香’和‘翠冠’为父母本，通过杂交获得矮化性状的后代（DPP）和乔化表型的后代（APP）。与APP相比，DPP植株高度降低了62.8%，节间长度显著缩短。茎尖组织切片观察显示，DPP细胞形状不规则，细胞平均长度较大，但纵向排布的细胞数量显著减少。两种表型梨之间的交叉嫁接试验表明，‘矮生梨’的矮化表型主要由地上部分决定，与根系无关。根据二者茎尖的RNAseq数据共鉴定出1401个差异表达基因,其中包含101转录因子。功能富集分析显示，植物激素、细胞分裂、细胞壁代谢等相关通路中的基因显著差异表达。在DPP中，若干BR信号转导和细胞周期相关基因表达显著下调；同时，一些调控BR和GA降解的基因表达上调。结合切片观察的结果与RNA-seq的数据推断，DPP的矮化表型主要归因于细胞分裂的不足。为进一步缩小候选基因集，将差异表达基因映射到前人所做的‘Le Nain Vert’矮化性状定位区间，共鉴定出4个关键基因。结合功能注释分析，发现其中一个DELLA基因可能在调控‘矮生梨’矮化表型中发挥重要的作用。本研究结果为进一步探索梨矮化的遗传和分子机制奠定了基础。

小麦全蚀病 (Take-all) 是一种具有毁灭性的土传病害，培育抗病材料是控制该病害的重要途径之一。华山新麦草 (Psathyrostachys huashanica Keng) 是小麦品种改良的重要遗传资源，特别是小麦全蚀病稀缺的抗性资源。在本研究中，相比感病亲本7182，小麦-华山新麦草渗入系H148的全蚀病抗性得到了显著性提升。为了明确H148抗病性的遗传机制，我们构建了H148和西农585的F₂遗传分离群体，且利用植物数量遗传体系“主基因+多基因”混合遗传模型分离分析法对其研究发现，H148的全蚀病抗性受到两对主效基因的共同控制，这两对主效基因存在一定的加性、显性和上位性效应。同时，结合集群分离分析法 (Bulked Segregant Analysis, BSA) 和小麦660K基因芯片筛选出与抗病相关的外源特异性SNP，主要分布于小麦2A染色体。根据特异性SNP开发竞争性等位基因特异性PCR (Kompetitive allele specific PCR, KASP) 分子标记，对F₂群体进行基因分型，最终在2A染色体的68.8-70.1Mb区间内定位到一个主效的QTL。该目标区间在小麦参考基因组序列上存在62个候选基因，经基因功能注释显示，两个可编码蛋白的基因与系统性提升植物根系抗性相关，被预测可能参与了小麦对全蚀病的抗病反应。总之，小麦-华山新麦草渗入系H148的选育以及抗病QTL的定位，以期为小麦抗全蚀病分子辅助育种和抗病基因的精细定位提供一定的参考信息。

植物抗虫性主要依靠限制害虫营养和有毒有害物质，但是，营养和有毒物质在植物抗蚜虫中的相对重要性仍未确定。在本论文中，我们探究了抗性小麦品种小偃22和易感小麦品种西农979对麦长管蚜的生长发育、繁殖、营养摄入量和转录组影响。结果显示，虽然小偃22的韧皮部汁液的营养质量（氨基酸：糖）比西农979的更高，但是，在小偃22上饲养的麦长管蚜的体重和繁殖力均显著低于在西农979上饲养的麦长管蚜。并且，在小偃22上饲养的麦长管蚜的蜜露分泌量也显著低于在西农979上饲养的麦长管蚜，这表明麦长管蚜在小偃22上饲养时，其摄入更少的韧皮部汁液。另外，通过比较在西农979和小偃22上饲养的麦长管蚜的转录组数据，我们发现共有600个差异表达基因，前20条差异表达基因显著富集的KEGG通路中有11条是与营养代谢相关的。我们共找到81个与糖、脂以及氨基酸代谢相关的差异表达基因，其中有59个差异表达基因是在小偃22上饲养的麦长管蚜中显著下调。另外，我们只找到18个与解毒代谢相关的差异表达基因，分别为8个UDP-glucuronosyltransferases，6个cytochromes P450 monooxygenases，1个glutathione S-transferase，2个ATP-binding cassette transporters以及1个major facilitator superfamily transporter，其中有12个差异表达基因是在小偃22上饲养的蚜虫中显著上调。以上结果说明，麦长管蚜从寄主小麦韧皮部获得的营养的数量和质量都对其生长发育很重要；小偃22较高的抗蚜性主要源于限制麦长管蚜取食韧皮部汁液，而非单纯依靠有毒物质。

Migratory insects make diverse adaptive strategies in response to changes in external environment.  Temperature has an impact on the survival, development, reproduction, and migration initiation of insects.  Previous research has primarily been focused on the effects of constant temperature on populations, but changing temperature has received less attention.  Three constant temperature treatments (20, 25 and 30°C) and three pupal-alternating temperature treatments (20–25, 25–20 and 25–30°C) were set up to study the relationship between temperature and population development by age-stage, two-sex life table analysis in the oriental armyworm, Mythimna separata Walker, a notorious migratory pest in grain crops.  The 25°C treatment was considered optimal with 20 and 30°C as low suitable temperature and high temperatures, respectively.  The survival rate was relatively low before third instar larvae at  20°C (63.0%) and 20–25°C (70.1%), and extreme low after pupal stage at 30°C (20.6%).  Developmental duration of each stage was negatively correlated with temperature.  The adult pre-oviposition period, when most migratory insects initiate migration, was the shortest at 25°C (2.69 d) but was lengthened at both low suitable (7.48 d for 20°C, 6.91 d for 25–20°C and 4.57 d for 20–25°C) and high temperatures (3.74 d for 25–30°C and 5.00 d for 30°C).  Both low suitable and high temperature decreased lifetime fecundity, net reproductive rate and the intrinsic rate of increase, with variability observed across developmental duration and stage during non-optimal temperature.  The results expand knowledge of the relationship between changing temperature and armyworm population development, and adaptive strategies in complex ambient environment.

Eating and cooking qualities (ECQs) of rice are important attributes due to its major influence on consumer acceptability. To better understand the molecular mechanism of the variation in ECQs, we investigated and compared the expressions among different alleles of the Waxy (Wx) gene and its effect on ECQs in specialty rice cultivars. The results showed that the accumulation of amylose was positively and significantly correlated to the level of mature Wx mRNA and granule-bound starch synthase I (GBSS I) in developing rice grain at 12 days after flowering. The amount of GBSS I and its activity together are the main factors controlling amylose synthesis. Differences in ECQs among five Wx allele types were investigated in samples from 15 rice varieties. The apparent amylose content (AAC) and gel consistency (GC) were similar in each type of Wx allele. The AAC followed the order, Wxa type>Wxin type>Wxb type>Wxmq type>wx. Contrary to this, the GC showed an opposite trend compared to AAC. There was a wide variation in rapid visco analyzer (RVA) profile among five Wx allele types, while varieties sharing a specified Wx allele had basically the similar RVA profile, although there was a slight difference in some RVA parameters, peak, hot paste and cool paste viscosities.

Insect pheromone-binding proteins (PBPs) play important roles in transporting hydrophobic pheromone components across the sensillum lymph to the surface of olfactory receptors (ORs). However, the PBPs of the oriental fruit moth, Grapholita molesta, an important destructive pest of stone fruits worldwide, are not well characterized. In this study, two new putative PBP genes, GmolPBP2 and GmolPBP3, were identified from G. molesta antennae. The deduced amino-acid sequences of these two putative PBP genes are characteristic of the odorant binding protein family, containing six conserved cysteine residues. The genomic DNA sequence of each gene contained two introns. However, the lengths and positions of the introns differed. RT-PCR analyses revealed that the two GmolPBP genes are only expressed in the antennae of female and male moths. Quantitative real-time PCR indicated that the transcription levels of GmolPBP2 are far greater than those of GmolPBP3 in both female and male antennae. GmolPBP3 showed higher transcription levels in female antennae than in male antennae, while GmolPBP2 showed similar transcription levels in both female and male antennae. The transcript levels of both genes were significantly different in premating and post-coitum individuals, implying that mating affects the process of sex pheromone reception. To better understand the functions, two GmolPBPs were expressed in Escherichia coli, and the ligand binding assays were conducted. Results showed that GmolPBP2 has strong binding affinities to two sex pheromone components, E8-12:Ac and Z8-12:Ac, as well as weaker binding affinities to Z8-12:OH and 12:OH. GmolPBP2 also bound some ordinary odor molecules. However, the affinity of GmolPBP3 to both sex pheromones and ordinary odor molecules was very weak. These results show that GmolPBP2 plays the main role in pheromone discrimination and recognition in the oriental fruit moth.