辣椒疫霉(Phytophthora capsici)对辣椒的致病力分化研究  

Pathogenicity differentiation of isolates of Phytophthora capsici to pepper

作　　者：李萍[1] 江涛[1] 高智谋[1] 戚仁德[1,2] 汪涛[2] 

机构地区：[1]安徽农业大学植物保护学院,合肥230036 [2]安徽省农业科学院植物保护研究所,合肥230031

出　　处：《植物病理学报》2012年第4期431-435,共5页Acta Phytopathologica Sinica

基　　金：国家公益性行业(农业)科研专项(3-20);安徽省自然科学基金项目(070411028)

摘　　要：辣椒疫霉（Phytophthoracapsici Leonian）是具有重大危害性的病原卵菌，其寄主范围较广，可引致辣椒、番茄、茄子、黄瓜、南瓜等多种重要蔬菜作物的疫病。由辣椒疫霉引起的辣椒疫病是一种毁灭性病害，在世界各地的辣椒种植区普遍发生，我国尤以江苏、浙江、安徽、上海等长江中下游地区发生严重。The studies on pathogenicity differentiation of isolates in Phytophthora capsici Leonian on pepper were carded out to explore the relationship between pathogenicity differentiation and isolate localities, the cor- relation between the pathogenicity and mycelium growth rates, and to provide more information for disease-re- sistant cultivar breeding and integrated management of the disease. Twenty-three isolates of P. capsici were obtained from the diseased peppers collected from Hefei, Huainan, Hexian, Qianshan, Yuexi, Nanjing and Qionglai by means of tissue isolation. The pathogenicity of the isolates from different areas was investigated by applying mycelium block stem wound inoculation on pepper seedlings and leaf in vitro inoculation, respective- ly. The cluster analysis of the pathogenicity data was done by unweighted pair group method with arithmetic averages （UPGMA） and the relationship between pathogenicity and geographical origin of isolates were ana- lyzed. The mycelium growth rates of the isolates were tested and the correlation between the pathogenicity to pepper and growth rates was investigated. The results showed that all the tested isolates caused pepper blight on the stems and leaves inoculated, but there was significant difference in the diameters of the stem lesions and the severity caused by different isolates. Based on the average diameters of the stem lesions, the pathogenicity of the isolates could be classified into three categories, strong, intermediate and weak. The pathogenicity tes- ted with stem wound inoculation in vivo was positively correlated to that tested with leaf in vitro inoculation （r = 0. 576 5, R2 = 0. 332 4）. However, the pathogenicity of P. capsici to pepper seedlings had little correlation with growth rate （R2 = 0.013 7）. It was suggested that there was significant differentiation in pathogenicity of isolates in P. capsici on pepper. The isolates could be classified into three types of pathogenicity, strongly, intermediately and weakly pathogenic. However, th

关 键 词：辣椒疫霉 致病力分化 长江中下游地区 辣椒疫病 毁灭性病害 寄主范围 蔬菜作物 种植区 

分 类 号：S436.413.1[农业科学—农业昆虫与害虫防治]