华南瓜类疫霉种群的致病力及其寄主嗜好性  

Virulence and host preference of Phytophthora melonis populations in South China

作　　者：吴永官[1,2] 胡春锦[3] 黄思良[4] 陆少峰[3] 车江旅[2] 付岗[3] 

机构地区：[1]广西大学农学院,南宁530005 [2]广西农业科学院蔬菜研究所,南宁530007 [3]广西农业科学院微生物研究所,南宁530007 [4]河南南阳师范学院生命科学与技术学院,南阳473061

出　　处：《植物保护学报》2012年第2期103-108,共6页Journal of Plant Protection

基　　金：广西农业科学院科技发展基金(200916);广西农业科学院基本科研业务专项基金[201017(基)]

摘　　要：2007—2010年从广西、广东两省(区)9个样区采集冬瓜、黄瓜疫病显症植株,经分离纯化鉴定共获得193株瓜类疫霉。采用菌丝块无伤接种法,将菌株接种冬瓜和黄瓜,测定、比较其对供试寄主植物的致病力及其寄主嗜好性。结果表明,病原群体对寄主植物冬瓜和黄瓜的致病力均存在明显分化现象,可分为强致病力、中等致病力及弱致病力3大类群;来自不同地区的瓜类疫霉对寄主植物冬瓜和黄瓜的致病力明显不同,多数样区以强致病力菌株占优势。瓜类疫霉种群中存在3种寄主嗜好型菌株,A型菌株对冬瓜和黄瓜均表现强致病力,与原始分离寄主无关;B型菌株仅对原始分离寄主冬瓜表现强致病力,而对黄瓜则表现为弱或中等致病力;C型菌株仅对原始分离寄主黄瓜表现强致病力,而对冬瓜则表现为弱或中等致病力。Phytophthora blight symptomatic cucumber and wax gourd plants were collected from 9 sampling areas in Guangxi Zhuang Autonomous Region and Guangdong Province during 2007-2010,from which 193 isolates of Phytophthora melonis were isolated and identified.Virulence of the isolates and their host preference were tested and compared using inoculating mycelial disks on wax gourd and cucumber plants using non-wounding method.The results showed that marked difference of virulence existed in the P.melonis populations.The isolates were divided into highly virulent,moderately virulent and weakly virulent groups.The highly virulent isolates were dominant in most of the area sampled on both host plants.At least three types of host preference were found among the P.melonis isolates.The isolates of A-type host preference were highly virulent on both wax gourd and cucumber plants regardless of their original isolation hosts.The isolates of B-type host preference were highly virulent only on the wax gourd plants from which they were isolated,and weakly or moderately virulent on the cucumber plants.The isolates of C-type host preference were highly virulent only on the cucumber plants from which they were isolated,and weakly or moderately virulent on the wax gourd plants.

关 键 词：瓜类疫霉 致病力分化 冬瓜 黄瓜 寄主嗜好性 

分 类 号：S436.42[农业科学—农业昆虫与害虫防治]