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.     

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.     

白粉菌效应蛋白研究进展

在病原菌与植物的相互作用过程中,病原菌分泌大量效应蛋白帮助其侵染植物,因此效应蛋白一直是植物病理学研究的热点课题.该文基于大量白粉菌效应蛋白的研究成果,就近年来白粉菌效应蛋白的生物信息学预测分析结果、功能效应蛋白鉴定及其作用机理和无毒效应蛋白研究进展等方面进行综述,同时对未来值得重点关注的研究方向进行探讨,以期为白粉菌致病性的研究提供理论参考.     

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。     

Insect defences: taste alteration and endoparasites

Taste sensation and food selection by animals can change adaptively in response to experience, for example to redress specific nutrient deficiencies. We show here, in two species of caterpillar, that infection by lethal parasites alters the taste of specific phytochemicals for the larvae. Given that these compounds are toxic to the parasites and are found in plants eaten by the caterpillars, their changed taste may encourage parasitized caterpillars to increase consumption of plants that provide a biochemical defence against the invaders.     

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.     

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。     

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.     

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.     

长白山区落新妇的开发利用及园艺栽培技术

落新妇（Astilbe chinensis）是一类具有观赏和药用价值的野生植物.通过引种驯化试验,旨在研究其生长特性.研究发现,落新妇具有喜肥、抗旱、耐涝、耐寒的特点.在有性繁殖过程中,赤霉素对种子萌发具有显著影响;无性繁殖可以通过切分根茎获得种源;栽培过程中,选择适时打顶可以提高观赏价值.此外,落新妇的主要病害有白粉病,虫害主要有红蜘蛛、尺蛾.     

Co-option of a default secretory pathway for plant immune responses

Cell-autonomous immunity is widespread in plant-fungus interactions and terminates fungal pathogenesis either at the cell surface or after pathogen entry. Although post-invasive resistance responses typically coincide with a self-contained cell death of plant cells undergoing attack by parasites, these cells survive pre-invasive defence. Mutational analysis in Arabidopsis identified PEN1 syntaxin as one component of two pre-invasive resistance pathways against ascomycete powdery mildew fungi. Here we show that plasma-membrane-resident PEN1 promiscuously forms SDS-resistant soluble N-ethylmaleimide sensitive factor attachment protein receptor (SNARE) complexes together with the SNAP33 adaptor and a subset of vesicle-associated membrane proteins (VAMPs). PEN1-dependent disease resistance acts in vivo mainly through two functionally redundant VAMP72 subfamily members, VAMP721 and VAMP722. Unexpectedly, the same two VAMP proteins also operate redundantly in a default secretory pathway, suggesting dual functions in separate biological processes owing to evolutionary co-option of the default pathway for plant immunity. The disease resistance function of the secretory PEN1-SNAP33-VAMP721/722 complex and the pathogen-induced subcellular dynamics of its components are mechanistically reminiscent of immunological synapse formation in vertebrates, enabling execution of immune responses through focal secretion.     

粗山羊草Y189抗小麦白粉病基因SSR标记

从粗山羊草[Aegilops tauschii(Coss.)Schmal]Y189中鉴定出1个显性抗小麦白粉病基因,暂定名为PmAe Y2.应用分离群体分组法(BSA)筛选到Xgwm583-5D、Xgwm174-5D、Xgwm182-5D和Xgwm271-5D标记与该基因之间的遗传距离分别为25.7、16.7、9.1和7.0 cM.根据连锁标记所在小麦微卫星图谱的位置,PmAe Y2被定位在5DL染色体上.分析基因所在染色体的位置、抗病性特征认为PmAe Y2是一个新的抗白粉病基因,并可用于分子标记辅助选择.     

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。     

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．     

Gene expression profiling related to powdery mildew resistance in wheat with the method of suppression subtractive hybridization

“Bainong 3217 × Mardler” BC₅F₄ wheat line at the initial stage of inoculation with powdery mildew pathogen (Erysiphe graminis DC) was used to construct a suppression subtractive hybridization (SSH) cDNA library. Totally 760 ESTs were obtained through sequencing. Similarity analysis of ESTs based on BLASTn and BLASTx with the sequences in GenBank, in combination with macroarray differential screening, revealed that 199 ESTs of 65 kinds were known to be functionally disease resistance related. Based on the gene expression profiling in the present study, it is postulated that salicylic acid (SA) and MAP-related signal transduction pathways were involved in powdery mildew resistance in wheat. System acquired resistance genes were predominant in terms of kinds and quantity. With the initiation of cell defense reaction, the genes conferring anti-oxidation substances were largely expressed and thus cell protection mechanism was activated. Much evidence revealed that phenylpropanes metabolic pathway was involved in phytoalexin synthesis in wheat powdery mildew resistance. Genes conferring some enzymes of structural modification of cell walls and proteinase inhibitors inhibiting pathogen growth were also detected. The genes controlling a few proteinases (mainly cysteine proteinase) had a considerable redundancy of expression.     

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.     

凉山州木本植物上的白粉菌调查

白粉菌是一类高等植物的重要专性寄生病原真菌,广泛分布于世界各地,能引致多种植物发生白粉病,并为害多种经济植物,引起严重损失。2008年9月—2019年5月对凉山州木本植物上的白粉菌进行了调查和研究,共鉴定出6属50余种,报道其中常见且危害严重的8种：冷水花白粉菌Erysiphe pileae (Jacz.) Bunk ex Braun;猪殃殃新白粉菌Neoerysiphe galii (S. Blumer)U. Braun;锡金白粉菌 Erysiphe sikkimensis Chona, J. N. Kapoor & H. S. Gill;毛茛耧斗菜白粉菌 Erysiphe aquilegiae var.ranunculi (Crev) (Grev.) R.Y. Zheng & G.Q. Chen;本间白粉菌Erysiphe hommae (U. Braun) U. Braun & S. Takam. 2000;刺槐白粉菌 Microsphaera robiniae Tai;草野钩丝壳 Uncinula kusanoi Syd. & P. Syd;三孢半内生钩丝壳 Pleochaeta shiraiana (Henn.)Kimbr. & Korf。     

枸杞白粉病防治药剂筛选试验

以3年树龄的"宁杞1号"为材料,研究了施蓝得可湿性粉剂和杜邦福星不同浓度对"宁杞1号"白粉病的防治效果。结果表明:70%施蓝得可湿性粉剂和杜邦福星400 g/L乳油对枸杞白粉病有较显著的防效,其中,70%施蓝得可湿性粉剂600倍液对枸杞白粉病的防治效果最好,更适宜于防治枸杞白粉病。