桃蚜虫霉病始发期的初始感染与接触传染  

Primary infection and contagious transmission of the Entomophthorales at the early stage of Myzus persicae mycosis

作　　者：尚素微[1] 冯明光[1] 

机构地区：[1]浙江大学微生物研究所,杭州310058

出　　处：《生态学报》2006年第10期3380-3384,共5页Acta Ecologica Sinica

基　　金：国家自然科学基金重点资助项目(30430150);国家重大基础研究计划课题资助项目(2003CB114203)~~

摘　　要：自2002年10月至2005年5月在杭州上空诱获桃蚜(Myzus persicae)的迁飞性有翅蚜2351头,将其带回室内在(21±1)℃和12L∶12D条件下单头饲养12d,其中639头在定殖后7d内发病死亡,初始感染率达27·2%。在病死有翅蚜中,99·4%系5种蚜科专化性虫霉侵染所致,新蚜虫疠霉(Pandora neoaphidis)的发生比例高达81·4%。带病迁飞的有翅蚜在发病死亡前具有一定生殖力,定殖后第6天平均累计产若蚜(2·4±0·13)头,远低于同期未带病有翅蚜产下的(11·6±0·33)头。在带病有翅蚜建立的后代蚜群中,接触传染在母蚜死亡2d后即可见到。在定殖后第12天,二级感染占总观察蚜群数的13·3%,三级感染占总观察蚜群数的4·4%,占二级感染蚜群数的33·3%。此时,未带病有翅蚜的后代蚜群的平均活蚜数达(50·6±2·30)头,而带病有翅蚜的后代蚜群平均仅有(21·5±1·98)头。结果表明,虫霉病能够通过寄主带病迁飞传至寄主迁入地,并在后代蚜群中相互传染而起到调节蚜虫数量增长的作用。Up to 2351 migratory Mates of green peach aphid Myzus persicae were trapped from air above the top floor of a tower building in Hangzhou, Zhejiang from October 2002 to May 2005 and individually reared for 12 days on detached cabbage leaves in Petri dishes at （21 ± 1 ）℃ under a photophase of 12L： 12D. During the first 7-day period, 639 alates died from mycoses caused by several obligate aphid pathogens in the Entomophthorales, representing a primary infection rate of 27.2 % among the air-trapped Mates. The obligate pathogens were predominated by Pandora neoaphidis at the rate of 81.4%. On average, the infected Mates produced significantly fewer nymphs （2.4 ± 0.13） than the uninfected （ 11.6 ± 0.33） within 6 days after colonization. Contagious transmissions of the mycoses were observed in the progeny colonies whose mother Mates were mycosed at least 2 days earlier. On day 12, 13.3% of their progeny colonies suffered from secondary infection and 4.4% from tertiary infection, which occurred among 33.3 % of the secondarily infected colonies. By the same day, the progeny colonies from the infected and uninfected Mates averagely consisted of （21.5 ± 1.98） and （50.6 ± 2.30） live aphids, respectively. The results highlight the significant role of the infected migratory Mates in initiation of Entomophthorales-caused mycoses on M. persicae colonized plants where the progeny population was regulated by the developing mycoses due to contagious transmission.

关 键 词：虫霉 桃蚜 迁飞扩散 蚜虫病害 初始侵染 接触性传染 

分 类 号：S476.12[农业科学—农业昆虫与害虫防治]