皖南与皖西南蚕区球孢白僵菌种群遗传结构的ISSR分析

由球孢白僵菌引起的家蚕白僵病是影响蚕业生产的重要因素之一.本研究在皖南泾县和皖西南潜山县蚕区的病蚕、蚕室环境、蚕室周边桑园、松林及农田调查取样，共分离出124株球孢白僵菌；通过ISSR分子标记对它们及用于防治松毛虫的菌株进行种群遗传结构分析，追踪家蚕白僵病的来源及传播途径.结果表明： 两个地区的球孢白僵菌种群均为异质性明显的种群.潜山的蚕病亚种群是多源的，而泾县的蚕病亚种群是单源的；泾县蚕病亚种群和潜山的蚕病优势亚种群具有典型的地方性，只在蚕室内循环侵染家蚕，引起低频常在性的地方性白僵病；而潜山的非优势亚种群可以在蚕室外的少数转主寄主中传播.在两地松林的松毛虫种群中流行的类群、真菌杀虫剂生产菌株以及在潜山蚕室附近引起螳螂种群流行病的类群均与蚕病类群无关，表明其对蚕业是安全的.

Population genetic structure of Beauveria bassiana from south and southwest Anhui sericultural regions: ISSR analysis.

White muscardine caused by Beauveria bassiana is an important factor affecting sericulture. In the present study, a total of 124 B. bassiana isolates
were obtained from the silkworm cadavers, rearing rooms and appliances, surrounding mulberry orchards, pine plantations, and croplands in Jingxian County of south Anhui and Qishan County of southwest Anhui. Together with the mass productionstrains, the isolates were analyzed for population genetic structure by ISSR markers to trace the origin and the spreading track of the muscardine. The resultsshowed that the two B. bassiana populations in Jingxian County and Qishan County were heterogenic, being monophyletic in Jingxian and polyphyletic in Qishan. Both the Jingxian population and the Qianshan predominant subpopulation were characterized typically by enzootic nature, i.e., low incidence and frequent occurrence, but the Qianshan non-predominant subpopulation could spread among some alternate hosts outside the rearing rooms. The groups prevailing in
pine caterpillar populations in the pine plantations of Qianshan and Jingxian, the production strains, and the epizootic strain prevailing in surrounding mantids were all not associated to the silkworm muscardine, displaying safety to sericulture.