栗疫病菌dsRNA的传递及其影响因素

FACTORS AFFECTING THE TRANSMISSION OF DSRNA IN CRYPHONECTRIA PARASITICA

对ｄｓＲＮＡ通过分生孢子、继代培养和菌丝融合传递的效率及其影响因素进行了研究。ｄｓＲＮＡ可通过分生孢子传递，但效果不稳定；提供光照和延长培养时间均可降低其传递效率，光照的不利影响更为明显；继代培养３０代未发现ｄｓＲＮＡ片段丢失，表明ｄｓＲＮＡ通过继代培养可稳定传递；菌丝融合传递ｄｓＲＮＡ受到营养体不亲和性的限制，但不亲和菌株间仍可获得一定的转化率，有的高达１００％；本研究使用两步转化的方法，明显地提高了弱毒力的转化率。

dsRNA could be transmitted to progeny through conidia with varying efficiency in culture.Both light and prolonging cultural time could reduce the transmission efficiency, but the effect of light on reducing transmission efficiency was more efficent.No dsRNA segments were found to loss after thirty generations subculture,indicating that dsRNA could transmitted stably through subculture. Vegetative incompatibility was a barrier for the tranfer of dsRNA from one isolate to another,but hypovirulence conversion between two vegetative incompatibility isolates could still obtain certain percentage, some cases up to 100%.The two step conversion method used in this study could increase the percentage of hypovirulence conversion significantly and will be a good way to raising conversion ratio between different VCG isolates.