栗疫菌弱毒力的转化及转化菌株的毒力测定

采用配对转化和室内、大田接种的方法研究栗疫菌低毒力的传递和生防潜力。从12个配对菌株中得到了6个转化菌株,不同的dsRNA供体菌和受体菌配对转化的效率不同,转化率从0到100%不等。室内枝段接种和大田接种测定的毒力表明,6个转化菌株、12个供体菌株、6个不能转化的受体菌+供体菌、6个转化菌株+供体野生型菌株处理的相对毒力都在80%以下,4者之间没有显著性差异,比12个受体菌和12个供体野生型菌株的毒力都低,表现弱毒力或中等毒力。前4者与后2者的差异都达到极显著水平,而供体野生型菌株的毒力(相对毒力72.73%-108.69%)与受体菌的毒力差异不显著。实验表明低毒力菌株的生防潜力比预期的高。

Transmission of Cryphonectria hypovirulence and virulence test of the transmitted isolates

The efficiency of dsRNA transmission in Cryphonectria parasitica was tested by co-culture the dsRNA donor and recipient, and virulence of dsRNA-containing isolates was determined by inoculation in both laboratory and field. Results showed that the transmission rate ranged from 0 to 100% within different combinations. The data of relative virulence tested by inoculation indicated that the virulence of 6 transmitted isolates, 12 donors, 6 pairs of non-transmitted isolates, and 6 pairs of transmitted isolate & wild type of the parent were extremely lower than that of recipient and wild type of donor. They were hypovirulent or mid-virulent, and no significant difference was observed among them. The wild type of donor possesses comparative virulence to recipient, which exhibited high virulence. The results suggested that the potentiality of the biological control for chestnut blight was higher than our expectation based on the assay data.