对白粉病敏感、抗性栽培小麦及杂交后代的蛋白质组分析

感病小麦京411、抗病小麦Brock及杂交后代近等基因系感染白粉菌后,发现京411感病,Brock和近等基因系抗病,因此白粉病抗性呈显性．对上述3种小麦的叶片进行蛋白质组分析,在感小麦的京411中有一个8kD／pI 5．3的特异蛋白,该蛋白在抗病品种Brock和杂交后代近等基因系中不存在,后者的蛋白质谱型与Brock相同．上述结果表明,幼苗抗白粉病特性的遗传与蛋白质谱型的遗传相类似,此结果也许可以为生产上筛选抗白粉病小麦品种提供生化依据．     

白粉菌对抗、感白粉病小麦品种叶片组织侵染情况的研究

采用透明染色法对白粉菌15号生理小种侵染的小麦叶片进行处理,观察不同时间段白粉菌对京411,Brock及其杂交后代近等基因系（NIL）叶片的侵染情况。结果表明：Brock,NIL抗病耐受性均强于京411,此结果可为今后抗病基因的克隆、植物抗性信号转导机制等研究提供细胞学上的依据。     

Breeding and molecular cytogenetic identification of wheat-Thinopyrum intermedium addition lines resistant to powdery mildew

Wheat-related species Th. intermedium was used to cross with common wheat Yannong 15. In the self progenies of the hybrid, two addition lines, Ⅱ-1-7-1 and Ⅱ-3-3-2, stable in cytology, were developed by cytology and powdery mildew resistance identification. Their chromosome number were 2n = 44 and formed 22 bivalents at PMC MI. In F₁ of the two addition lines crossing with Yannong 15, there appeared about one univalent at PMC MI, respectively. Resistance identification in greenhouse and field using the No. 15 and mixed strains of E. gramnis f. sp. tritici showed that they were immune to powdery mildew. Chromosome number and resistance identification using the F² single plants of the addition line crossing with Yannong 15 indicated that the resistant gene was located on the alien chromosomes. In situ hybridization using St and E genomic DNA as probe showed that the added chromosome in the two addition lines probably came from the E genome of Th. intermedium, which indicated that a pair of E genome chromosomes carried a new resistant gene to powdery mildew.     

A transgenic wheat with a stilbene synthase gene resistant to powdery mildew obtained by biolistic method

Stilbene, a kind of phytoalexin, plays an important role in resistance to fungal and bacterial infection in plants. It strongly inhibits the growth of fungi and sprout of spore. Stilbene synthase gene (Vst1) obtained from grapevine has been transferred into common spring wheat Jinghong 5 by using the biolistic transformation method. Five transgenic plants (T₀) were obtained from the bombarded 2014 immature embryos. One immune plantlet and 3 plantlets with mid-resistance to powdery mildew were identified from the transgenic plants of T₃ generation which came from 2 T₀ transgenic plants.     

4个小麦品种的抗白粉病遗传分析

抗病品种郑315、CP87-26-12和91138-16-2-13-12,与感病品种豫麦49号杂交的F1代表现抗病,F2代抗、感单株的分离比例为31,表明这3个品种均携带1对显性抗病基因.N97189-2和豫麦18号的杂交F1代对白粉病表现高感,F2代抗、感单株的分离比例为13,由此推断N97189-2对白粉病的抗性由1对隐性基因控制.     

小麦F1和F2代抗白粉病性的配合力遗传力及相关分析

用８个抗白粉病性不同的春小麦品种进行不完全双列杂交，对亲本及杂交后代的抗白粉病性进行了遗传分析，结果Ｆ１和Ｆ２代抗白粉病性一般配合力和特殊配合力方差及ＭＳｇ．ｃ．ａ／ＭＳｓ．ｃ．ａ均达显著或极显著水平，抗白粉病性加性效应为主。     

VIGS技术初步鉴定RgMLO6和RlMLO7基因对白粉病的负调控功能

为了探讨蔷薇科植物MLO基因在抗白粉病中的作用,研究应用病毒诱导的基因沉默技术(virus induced gene silencing,VIGS)抑制了大花香水月季RgMLO6基因和长尖叶蔷薇RlMLO7基因的表达,随后接种白粉菌对这2个基因进行抗性鉴定. 研究发现在VIGS载体转化植株叶片20 d后,RgMLO6和RlMLO7基因的相对表达量显著下降了80%～90%,沉默效果明显. 分别对2个基因沉默后的嫩叶进行白粉病抗性鉴定,大花香水月季和长尖叶蔷薇的抗性水平较对照组均提高. 显微镜观察白粉菌接种2个基因沉默后植株叶片中菌丝体的生长情况,整体表现出沉默植株叶表皮细胞上的白粉菌生长较对照组生长缓慢. 结果表明RgMLO6与RlMLO7基因对蔷薇科植物的白粉病有负向调控作用.     

小麦F2代白粉病抗、感病特性RAPD标记的比较研究

用２０个随机引物,以抗白粉病（７９２０１－１１－７、临远７０６９）和感白粉病（中麦２号、郑８３１）的高产小麦品种为亲本,杂交获得的Ｆ２群体接种白粉病菌１５号小种,并进行ＤＮＡ随机扩增多态性（ＲＡＰＤ）分析．从中选育高产、抗病个体和研究抗感特性在分子水平上的差异．     

小麦抗白粉病性与酶活性的关系

测定了７个小麦抗，感白粉病品种抽穗期叶片苯丙氨酸解氨酶，多酚氧化酶，过氧化物酶的活性。结果表明，在抗病品种中，三种酶的活性均高于感病品种，酶的活性病情指数呈负相关。     

麦田小气候与白粉病流行关系的模拟研究

本文根据不同类型麦田小气候的差异修改了已有的白粉病流行的模拟模型,模拟和预测了不同种植密度麦田白粉病的流行情况。结果表明:当麦田种植密度大时,其小气候相对湿度较高而温度则相对较低,这类麦田的白粉病流行较快;反之,相对湿度较低而温度则相应较高,这类麦田白粉病流行则较慢。     

凤仙白粉病的病原菌鉴定

凤仙白粉病菌使凤仙花科植物叶片出现白色病斑.对河南商丘地区的凤仙白粉病菌进行了致病性分析、形态学及分子生物学鉴定.该病原菌分生孢子椭圆形或桶形,大小为22～28μm×16～21 μm.分生孢子梗直立,圆柱形,简单不分枝,包含1个足细胞,1～3个远基细胞,3～6个排列成链的桶形分生孢子,大小为112～180 μm×9～1...     

根施不同形态硅制剂对小麦白粉病的作用效果研究

本文研究了根施三种不同形态硅制剂对小麦白粉病的作用效果.结果表明,溶胶态的氧化硅溶胶、分子态的正硅酸乙酯和离子态的硅酸钠对小麦白粉病均有一定的作用效果,防治效果分别为1.02%、51.36%、54.08%.     

Timing of plant immune responses by a central circadian regulator

The principal immune mechanism against biotrophic pathogens in plants is the resistance (R)-gene-mediated defence. It was proposed to share components with the broad-spectrum basal defence machinery. However, the underlying molecular mechanism is largely unknown. Here we report the identification of novel genes involved in R-gene-mediated resistance against downy mildew in Arabidopsis and their regulatory control by the circadian regulator, CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1). Numerical clustering based on phenotypes of these gene mutants revealed that programmed cell death (PCD) is the major contributor to resistance. Mutants compromised in the R-gene-mediated PCD were also defective in basal resistance, establishing an interconnection between these two distinct defence mechanisms. Surprisingly, we found that these new defence genes are under circadian control by CCA1, allowing plants to 'anticipate' infection at dawn when the pathogen normally disperses the spores and time immune responses according to the perception of different pathogenic signals upon infection. Temporal control of the defence genes by CCA1 differentiates their involvement in basal and R-gene-mediated defence. Our study has revealed a key functional link between the circadian clock and plant immunity.     

小麦中源于中间偃麦草抗白粉病基因PmCH5026的SSR定位

CH5026是衍生于八倍体小偃麦TAI7045的新品系,用高感品种(系)CH5065、晋太170分别与CH5026配置组合,于温室接种并调查F2、F3、BC1F2群体的抗感分离之比进行遗传分析,结果表明CH5026成株期对白粉菌E09小种的抗性受1对显性基因控制,暂命名为PmCH5026.使用集群分离分析法(BSA),用378对SSR引物对CH5026×CH5065 F2代群体进行分析,筛选到标记Xcfd233、Xbarc11和Xgwm539与抗性基因连锁,位置顺序为:Xcfd233-7.2cM-PmCH5026-4.9cM-Xbarc11-5.5cM-Xgwm539.根据小麦微卫星遗传连锁图及利用中国春第2同源群缺四体、双端体对SSR标记的定位结果,将PmCH5026定位在染色体2DL上.     

商丘地区番茄白粉菌的鉴定

对中国商丘地区首次检出的番茄白粉菌进行了形态特征的观察、致病性检测及分子鉴定.结果显示,该病原菌经人工接种可导致番茄栽培品种致病,发病症状与自然状态一致,而对野生品种无作用;在显微镜下分生孢子单生呈椭圆状,孢子梗直立无分支;核糖体DNA转录间隔区(ITS)序列与来自Oidium neolycopersici的5条序列聚为1支,亲缘关系最近,而与来自Oidium lycopersici的3条ITS序列亲缘关系较远.以上结果表明,来自商丘的番茄白粉菌为O. neolycopersici.     

我国番茄白粉病抗病育种研究现状

本文阐述了国内对番茄白粉病抗病性的研究现状,包括番茄白粉病化学防治方法及抗源鉴定方法,抗病遗传规律及抗病机理等,并对番茄白粉病抗病育种中存在的问题进行了讨论。     

Molecular mapping of a novel yellow rust resistance gene of wheat using microsatellite markers

Identification and genetic analysis of yellow rust resistance have suggested that wheat line R55 carries single dominant gene conferring yellow rust resistance. The bulked segregant analysis (BSA) for an F₂ population using microsatellite marker technique has indicated that the yellow rust resistance gene is located on the short arm of chromosome 1B, tightly linked to the microsatellite markers WMS11-193 bp and WMS18-184 bp, the linkage distance between the markers and the gene is 1.9 cM. This gene has been formally namedYr26. It is inferred from the pedigree, resistance and gene locus analysis that theYr26 has been transferred fromTriticum turgidum L. and is different from the other known yellow rust resistance genes.     

Breeding and molecular cytogenetic identification of wheat-Thinopyrum intermedium addition lines resistant to powdery mildew

Wheat-related species Th. intermedium was used to cross with common wheat Yannong 15. In the self progenies of the hybrid, two addition lines, Ⅱ-1-7-1 and Ⅱ-3-3-2, stable in cytology, were developed by cytology and powdery mildew resistance identification. Their chromosome number were 2n = 44 and formed 22 bivalents at PMC MI. In F1 of the two addition lines crossing with Yannong 15, there appeared about one univalent at PMC MI, respectively. Resistance identification in greenhouse and field using the No. 15 and mixed strains of E. gramnis f. sp. tritici showed that they were immune to powdery mildew. Chromosome number and resistance identification using the F2 single plants of the addition line crossing with Yannong 15 indicated that the resistant gene was located on the alien chromosomes. In situ hybridization using St and E genomic DNA as probe showed that the added chromosome in the two addition lines probably came from the E genome of Th. intermedium, which indicated that a pair of E genome chromosomes carried a new resistant gene to powdery mildew.     

SNARE-protein-mediated disease resistance at the plant cell wall

Failure of pathogenic fungi to breach the plant cell wall constitutes a major component of immunity of non-host plant species--species outside the pathogen host range--and accounts for a proportion of aborted infection attempts on 'susceptible' host plants (basal resistance). Neither form of penetration resistance is understood at the molecular level. We developed a screen for penetration (pen) mutants of Arabidopsis, which are disabled in non-host penetration resistance against barley powdery mildew, Blumeria graminis f. sp. hordei, and we isolated the PEN1 gene. We also isolated barley ROR2 (ref. 2), which is required for basal penetration resistance against B. g. hordei. The genes encode functionally homologous syntaxins, demonstrating a mechanistic link between non-host resistance and basal penetration resistance in monocotyledons and dicotyledons. We show that resistance in barley requires a SNAP-25 (synaptosome-associated protein, molecular mass 25 kDa) homologue capable of forming a binary SNAP receptor (SNARE) complex with ROR2. Genetic control of vesicle behaviour at penetration sites, and plasma membrane location of PEN1/ROR2, is consistent with a proposed involvement of SNARE-complex-mediated exocytosis and/or homotypic vesicle fusion events in resistance. Functions associated with SNARE-dependent penetration resistance are dispensable for immunity mediated by race-specific resistance (R) genes, highlighting fundamental differences between these two resistance forms.