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1.
利用28S rDNA D1/D2区和ITS rDNA序列鉴定甜瓜白粉病病原菌 总被引：2，自引：2，他引：0
为了明确宁夏干旱带压砂甜瓜白粉病病原菌,从病原菌分生孢子中提取DNA,PCR扩增ITSrDNA和28S rDNA D1/D2区段,测序后进行BLAST比对.结果表明,病原菌的ITS rDNA和28SrDNA D1/D2序列与菜豆叉丝单囊壳白粉菌Podosphaera phaseoli、凤仙花又丝单囊壳白粉菌P.bal-saminae、菊科叉丝单囊壳白粉菌P.fwca、苍耳单囊壳白粉菌P.xanthii、瓜类单囊壳白粉菌P.fuligi-nea等叉丝单囊壳属Podosphaera的多个种的ITS rDNA和28S rDNA D1/D2序列之间相似度均大于99%,鉴定甜瓜白粉病病原菌为叉丝单囊壳属Podosphaera. 相似文献
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为明确小豆白粉病病原菌的种类以及小豆种质资源对白粉病的抗性,采用形态学和系统发育学方法对近年来在北京市发生的小豆白粉病病原菌种类进行鉴定,并采用室内苗期人工接种法评价小豆常见栽培品种（系）对白粉病的抗性。结果表明,从北京市采集的感白粉病小豆病样中培养获得病原菌BJ1,该菌能在小豆叶片和茎上产生明显的白色粉斑,分生孢子梗直立,不分枝,分生孢子单细胞,成链状着生于分生孢子梗上,呈椭圆形或卵圆形。通过rDNA-ITS序列系统发育分析,小豆白粉病菌BJ1被鉴定为白粉菌目白粉菌科的苍耳叉丝单囊壳Podosphaera xanthii。室内苗期人工接种条件下,19个供试小豆品种（系）接种小豆白粉病菌BJ1后均可发病,其中9个审定品种均表现为中度感病或高度感病,10个优良品系发病略轻。 相似文献
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为明确海南省苦瓜白粉病的病原菌、生理小种及苦瓜对白粉病的抗性遗传规律,结合形态学鉴定和分子鉴定解析白粉病菌及生理小种种类,通过显微镜观察白粉病菌侵染过程,并应用主基因+多基因混合遗传模型分析法探讨苦瓜对白粉病的主要抗性遗传规律。结果表明:采集自海南省6个市(县)的苦瓜白粉病病原菌均为单囊壳白粉菌Sphaerotheca fuliginea,属生理小种2F,该菌在侵染苦瓜叶片时有4个关键时期:接种后4 h为分生孢子萌发高峰期,8 h为附着孢形成高峰期,16～24 h为次生菌丝形成高峰期,5 d为分生孢子梗形成高峰期。将其接种于苦瓜抗、感品系,对白粉病的抗性符合2对加性-显性-上位性主基因+加性-显性多基因模型,主基因和多基因共同控制苦瓜对白粉病的抗性,其中以主基因遗传为主,且会受到环境变异的影响。根据苦瓜抗性遗传规律,F2代主基因遗传率最高,受环境影响最小,在苦瓜的白粉病抗性育种中,以早期世代F2代作为有效选择世代。研究表明白粉病菌侵染叶片的前2 d是白粉病防治的最佳时期,所以在白粉病易发的物候期,可将防治时间提前1～2 d。 相似文献
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为明确云南省燕麦白粉病病原菌种类及其致病力,结合形态学和分子生物学对其进行鉴定分析,并测定了该病原菌对21个燕麦品种的致病力。结果表明,燕麦白粉病病原菌孢子梗不分支、无色、基部呈球形膨大,顶端生有成串的分生孢子,分生孢子无色,呈长卵圆形、单胞,大小为18.84~29.12μm×6.53~10.71μm,初步鉴定为禾本科布氏白粉菌Blumeria graminis(DC.)Speer;分子生物学鉴定结果表明病原菌rDNA-ITS区序列与禾本科布氏白粉菌燕麦专化型Blumeria graminis f.sp.avenae的同源性为100%,结合形态特征与分子鉴定最终将云南燕麦白粉病菌鉴定为禾本科布氏白粉菌燕麦白粉病菌专化型。致病力测定结果显示,21个供试燕麦品种发病株率为100.00%,病情指数为91.73~100.00,发病初期平均发病株率和病情指数分别为14.56%和1.75,35 d后发病株率和病情指数分别增长了85.44%和95.74%,表明云南省燕麦白粉病菌的致病力强。 相似文献
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为明确宁夏回族自治区温室瓜菜白粉病菌的分类地位,对采自该地区温室的南瓜、黄瓜和甜瓜上的白粉病菌基于ITS序列分析进行分子鉴定;利用孢子捕捉器对温室中甜瓜白粉病菌的孢子量进行监测,分析环境因子、孢子量和病情指数之间的关系,并采用逐步回归分析法构建温室甜瓜白粉病的流行预测模型。结果表明,基于ITS序列的分子鉴定结果,3种瓜菜白粉病的病原菌均为单囊壳白粉菌Podosphaera xanthii。发病期间,每日温室中甜瓜白粉病菌的孢子量在12:00—16:00时段最多,占24 h内总孢子量的34%~81%,20:00—08:00时段最少;白粉病菌孢子的释放与光照强度有关,相关系数为0.602。第t天的病情指数与标准累积温度、标准累积湿度、t-4 d前08:00—12:00时段的累积孢子量、第t-4天16:00—20:00时段的孢子量均具有显著的相关性,相关系数分别为0.935、0.938、0.956和0.921。以标准累积湿度和第t-4天16:00—20:00时段的孢子量为预测变量构建了温室甜瓜白粉病流行预测模型,决定系数为0.962,表明该模型具有较好的实际应用价值。 相似文献
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东北春麦区小麦白粉菌的侵染循环 总被引：9，自引：1，他引：9
小麦白粉菌(Blumeria graminis DC.Speer)可以在我国东北的南部冬麦区以菌丝垫形态潜伏在小麦苗基部叶片和叶鞘上越冬,以混在干燥保存的小麦种子中的闭囊壳越夏。自生麦苗和白粉病的野生寄主在侵染循环中不起作用。小麦白粉菌的毒力频率(Vf)分析表明,公主岭、沈阳、海城、大连和烟台的小麦白粉菌同属于一个群体。东北春麦区小麦白粉病初发日期和高空天气图分析表明,东北春麦区小麦白粉病的初侵染菌源来自胶东半岛冬麦区。在一定的天气系统控制下,小麦白粉菌的分生孢子随夏初的偏南气流,在700毫巴高度层向北传播,进入东北春麦区。随降雨沉降,并侵染小麦植株。 相似文献
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能产生分生孢子器的Ampelomyees quisqualis是白粉菌上的一种重寄生真菌,Cesati(1852)在一百三十年前首次作了记载。这种重寄生菌广泛寄生于多种白粉菌上。白粉菌是专性寄生,它的寄主范围很有限,但重寄生菌能够人工培养,且比它寄主的专化性更弱。在挪威温室黄瓜上有两种白粉病流 相似文献
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园林植物白粉病是由白粉菌科的真菌引起的病害。植物患病后,不仅使植物失去原有的观赏价值,而且发生严重会给生产带来较大的经济损失。为摸清南昌地区园林植物白粉病的发生和为害情况,在进行实地调基础上查,初步鉴定出南昌园林植物白粉病26种,分布在19科植物上,同时对该病提出防治对策。 相似文献
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小麦白粉病菌对三唑酮抗药性的监测 总被引：12，自引：0，他引：12
小麦白粉病是世界性病害,因缺少抗性品种,长期以来依赖于药剂防治。三唑类药剂是防治白粉病的高效药剂,由于长期、大量、单一的应用,致使病菌抗药性发生。我国胶东沿海是小麦白粉病的多发地区,使用三唑酮防治该病近10年,病菌抗药性的研究与探明对农业生产具有指导意义。应用小株法和叶段法进行小麦白粉菌对三唑酮抗药性监测,3年共监测单孢堆菌系333个。结果较基线MIC高3～7倍者占86％,表明已进入抗药性发展初期。由于近年春旱抑制发病而抗药性发展很慢,一旦白粉病有中度以上流行条件,大面积连续用药即会发生抗药性,使防治失效,威胁生产,建议尽早治理。 相似文献
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Evidence for an Osmotic Mechanism in the Control of Powdery Mildew Disease of Wheat by Foliar-applied Potassium Chloride 总被引：3，自引：0，他引：3
P.S. Kettlewell J.W. Cook D.W. Parry 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(3):297-300
The mechanism by which foliar application of potassium chloride solution reduces symptoms of powdery mildew disease (Erysiphe graminis f.sp. tritici) of wheat was investigated. The hypothesis that potassium chloride reduces mildew by an osmotic effect on spore germination was tested in three glasshouse experiments. Either potassium chloride solution or the osmoticum polyethylene glycol 200 was sprayed on wheat at the three- or four-leaf stage. The plants were inoculated with spores and spore germination and leaf area affected by mildew were assessed. Leaf water potential was determined as a measure of the osmotic effect of the treatments. Spore germination and leaf area affected by mildew were related to leaf water potential using regression analysis in groups on the data averaged over the three experiments. Both spore germination on the leaf and leaf area affected by mildew were reduced as leaf water potential decreased. There was no difference between potassium chloride or polyethylene glycol in the relationship between spore germination and leaf water potential, but polyethylene glycol was slightly less effective at reducing mildew symptoms at any given leaf water potential. The results are compatible with the hypothesis that potassium chloride reduces symptoms of powdery mildew by an osmotic effect on spore germination. 相似文献
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Diversity of powdery mildew pathogens infecting pea (Pisum sativum) in the US Pacific Northwest was investigated using both molecular and morphological techniques. Phylogenetic analyses based on rDNA ITS sequences, in combination with assessment of morphological characters, defined two groups of powdery mildews infecting pea. Group I (five field samples and three glasshouse samples) had ITS sequences 99% similar to those of Erysiphe pisi in GenBank and exhibited simple, mycelioid type of chasmothecial appendages typical of E. pisi. Erysiphe pisi is normally considered as the powdery mildew pathogen of pea. Group II (four glasshouse samples and two field samples) had ITS sequences 99% similar to those of E. trifolii and produced chasmothecia with dichotomously branched appendages similar to those of E. trifolii. There are fourteen nucleotide differences in the ITS region between the two groups. The correlation of rDNA ITS sequences with teleomorphic features for each of the two groups confirms their identity. Repeated samplings and artificial inoculations indicate that both E. pisi and E. trifolii infect pea in the US Pacific Northwest. Erysiphe trifolii is not previously known as a pathogen of pea. The existence of two distinct powdery mildew species infecting pea in both glasshouse and field environments may interfere with the powdery mildew‐resistance breeding programmes, and possibly explains putative instances of breakdown of resistance in previously resistant pea breeding lines. 相似文献
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Occurrence of New Powdery Mildew on Greenhouse Tomato Cultivars 总被引：2，自引：0，他引：2
Yoshinori MATSUDA Koichi KASHIMOTO Yoshihiro TAKIKAWA Rika AIKAMI Teruo NONOMURA Hideyoshi TOYODA 《Journal of General Plant Pathology》2001,67(4):294-298
During a year-round survey on the occurrence of powdery mildew on greenhouse-cultivated tomato plants, the disease was most
severe in June and July. All tomato plants (45 commercial cultivars and 11 breeding lines) tested were infected with the pathogen
but had different degrees of susceptibility. The pathogen was epiphytic and produced white, round pustules mainly on leaves
of tomato plants. The pathogen produced conidia singly on conidiophores and forked appressoria on inoculated tomato leaves
and seemed to be an Oidium sp. of Erysiphe polygoni type.
Received 18 December 2000/ Accepted in revised form 22 July 2001 相似文献
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接种黄瓜白粉菌后16 h的黄瓜叶片用透明胶带在子叶表面粘孢子取样的平均发芽率与用台盼蓝染色后在光学显微镜下调查的发芽率分别为83.7%和85.0%,t测验无显著差异,表明透明胶带取样的发芽率可以代表黄瓜叶片上白粉病菌孢子的发芽率。采用孢子萌发法和叶碟法分别测定了醚菌酯、植物源活性组分大黄素甲醚(P3D)对8个黄瓜白粉菌菌株的EC50。统计结果表明:采用两种方法测定醚菌酯P、3D对黄瓜白粉菌的EC50的相关系数的平方值分别为0.880、.99,表明两种方法的测定结果有很强的相关性;采用该孢子萌发法可评价化合物对植物专性寄生病菌如白粉菌孢子萌发的生物活性。 相似文献
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Derek W. Hollomon Ian Wheeler Keith Dixon Christopher Longhurst George Skylakakis 《Pest management science》1997,51(3):347-351
The new powdery mildew fungicide quinoxyfen belongs to the novel quinoline class of chemistry. Although its biochemical mode of action is unknown, quinoxyfen does not act in the same way as other cereal fungicides. It is a systemic protectant which inhibits the early stages of mildew infection on a wide range of crops, and provides season-long protection from a single early-season spray applied around GS 31. The base-line sensitivity profile of quinoxyfen was defined for barley powdery mildew (Erysiphe graminis f.sp. hordei) from over 340 field isolates collected from different parts of the UK from 1991 onwards. Sensitivities ranged from <0·0001→0·16 mg litre-1 with a mean of 0·003 mg litre-1. Current work is extending the base-line sensitivity studies to wheat powdery mildew (E. graminis f.sp. tritici), and includes isolates from European trials, but so far this new data set has shown no differences from barley powdery mildew. Quinoxyfen-resistant mutants were generated in the laboratory, and some similar resistant strains were obtained from treated field crops. These laboratory and field strains were always defective, in some way, for sporulation and, curiously, all required the presence of quinoxyfen for survival in culture. Attempts to generate resistant mutants that sporulated normally were unsuccessful. These studies suggested that the resistance risk for quinoxyfen is low. The recommended anti-resistance strategy accompanying introduction of quinoxyfen avoids seed treatments and late-season applications. Instead, a single early (GS 31) treatment using either pre-formulated mixtures or alternating with a fungicide with different mode of action is recommended. This strategy will be supported by continued monitoring of wheat and barley powdery mildew. ©1997 SCI 相似文献
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Occurrence of a new powdery mildew of greenhouse tomato in Greece, caused by Erysiphe sp. 总被引：2，自引：2，他引：0
An epiphytic pathogen causing powdery mildew on greenhouse-grown tomato (Lycopersicon esculentum) appears for the first time in Greece and is identified as belonging to the genus Erysiphe. 相似文献