【作者】 张驰；

【导师】 纪明山；

【作者基本信息】 沈阳农业大学 ， 植物病理学， 2004， 硕士

【摘要】 本试验系统地研究了目前辽宁省主要保护地蔬菜种植区的番茄叶霉病菌[Fulvia fulva(Cooke)Ciferr]对杀菌剂氟硅唑(flusilazole)的抗药性现状、敏感菌株抗药性诱导、抗药性菌株生物学特性以及与其它药剂的交互抗药性关系。明确了番茄叶霉病菌对氟硅唑的抗药性水平、抗药性分布情况、抗药性突变体的适合度、与其它药剂的交互抗药性，试验结果表明针对番茄叶霉病菌而言，氟硅唑属于低抗药性风险杀菌剂。本研究对辽宁省番茄叶霉病的防治具有重要指导意义。 主要研究结果如下： 从辽宁省各保护地番茄植株上采集分离到200个番茄叶霉病菌菌株，经室内敏感性测定分别检测到了番茄叶霉病菌对氟硅唑的敏感、低抗、中抗、高抗菌株，这四类菌株分别占到42％、47.5％、7.5％、3％。从这个结果看，敏感和低抗菌株是辽宁省内的优势菌株。虽然检测到6株高抗菌株，但其数量少还未形成规模且地域比较集中，因此认为辽宁省内的番茄叶霉病菌还未对氟硅唑产生严重的抗药性。 用紫外线诱导、药剂驯化、紫外线和药剂共同作用三种方法对目标敏感菌株XY1进行了抗药性诱导，共获得了三种抗药性突变体。经检测发现，紫外线诱导的突变体为低抗水平，药剂诱导的为中抗水平，两者共同诱导的为高抗水平。这一结果说明，氟硅唑在叶霉菌产生抗药性的过程中起主要作用，阳光中的紫外线起到辅助作用，两者可以产生累加效应促使高抗菌株的产生。 抗药性菌株生物学特性的试验表明叶霉病菌在产生抗药性的初期它的适合度不会受到影响，但一旦抗药性水平达到高抗，则生长繁殖能力较敏感菌株显著下降。从渗透敏感性的试验结果可以初步判断叶霉菌随着抗药性的增加致病性降低。遗传稳定性的结果试验证明抗药性突变体的抗药性不能以 摘要无性繁殖稳定遗传，可逐步恢复为敏感菌株。这些结果说明，叶霉菌对氟硅哇的抗药性遗传应该是由多基因控制的，抗药性具有累加效应。从抗药性突变体生物学特性看，突变体的竞争能力较敏感菌株下降，难以发展成为优势菌株。 室内交互抗药性测定表明:氟硅哇与多菌灵、腐霉利、啼菌酷均无交互抗药性，但与同属三哇类的睛菌哇、三哇酮有正交互抗药性。叶霉菌对新药啼菌醋极其敏感，是生产上值得推广的一种新的有效药剂。 以上试验结果表明，氟硅哇对番茄叶霉菌是一种低度抗药性风险的杀菌剂。更多还原

【Abstract】 In this paper the resistance of Fulvia fulva to flusilazole, inducing resistance of sensitive isolates, biological characteristics of mutant-isolate and cross-resistance to other fungicides were studied. The level and distribution of F.fulva resistance in Liaoning, the fitness of mutants, the relation of cross-resistance between flusilazole and other fungicides were confirmed. It showed that the inherent risk of flusilazole to F. fulva is low. The results can support to build fungicide resistance management strategies and offer references to develop new fungicides. The results were as the follows:1. Two hundred isolates of F. in tomato was obtained in 2002 and 2003 from several main protection fields in Liaoning province. Sensitivity of these isolates to flusilazole was determined by the methods of mycelium growth inhibition. Four kinds of isolates were found, they are sensitive isolates, low level resistant isolates, moderate level resistant isolates, high level resistant isolates, the percentage of them was 42%, 47.5%, 7.5%, 3% respectively. Sensitive and low level resistant isolates are predominant isolates. Six high level resistant isolates were detected but the quantities and distribution is not abroad. The results showed that F.fulva in Liaoning hasn’t developed severe resistance.2. Flusilazole-resistant mutants to F. fulva have been acquired by ultraviolet-inducing and chemical-traming and the two methods use together. The resistant level of mutants by three methods belonged -to low level resistance, moderate resistance and high level resistance respectively. This results showed that fungicide played an important role in development of resistance while ultraviolet is secondary. When used together they can accelerate the emergence of high level resistante isolates.3. Significant differences in mycelium growth, fresh weight and osmotic sensitivity were observed between sensitive and high level resistant isolates. This means the fitness of the high level resistante isolates decreased significantly. But the other kinds of isolates exhibited no difference with sensitive isolates. The resistance of mutants and field-mutants can’t pass down stably, they can become sensitive isolates after they were continuously transferred in PDA medium without fungicide, but the high level resistante isolates is difficult to do this. The research indicated that the heredity of resistance in F. fulva to flusilazole is control by polygene. Mutants have lower competition capacity than that of sensitive isolates, and it is difficult to become predominant isolates.4. There was no cross-resistance between flusilazole and procymidone as well as azoxystrobin, carbendazim, whereas there was positive cross-resistance between flusilazole and myclobutanil as well as triadimefon. Azoxystrobin is a kind of effectivenew fungicide to control Fulviafulva and is good for spreading. 5. On the whole, we assumed that the inherent risk of flusilazole to F.fulva is low.更多还原