不同来源向日葵菌核病分离物致病性分化研究

Study on Differentiation in Pathogenicity of Sclerotinia sclerotiorumof Sunflowers from Different Regions

为进一步揭示核盘菌种群内是否存在着致病性分化现象,采用离体叶片菌饼接种法,以向日葵品种龙食葵3号为供试寄主,对采集于内蒙古和黑龙江省不同地区的20个向日葵核盘菌分离物进行了致病性测定。结果表明:接种72h后,除4个分离物不能致病外,其余16个分离物均能致病,但各分离物所致病斑直径差异很大,为1.00～80.00mm。说明不同来源核盘菌菌株间致病性存在着显著的差异,且这种致病性分化与菌株来源没有明显的相关性。

In order to indicate the pathogenicity existed or not in the strains of Sclerotinia sclerotiorum twenty strains of S. sclerotiorum isolated from sunflowers in different regions of Inner Mongolia and Heilongjiang province were tested for their pathogenicity with Longshikui No. 3 as host using the inoculation method of placing the mycelial plugs on the leaves in vitro. The results showed that sixteen strains of S. sclerotiorum could infect the leaves of sunflowers after inoculated 72 hours except for the other four strains, but the lesion sizes ranged from 1.00 to 80. 00 mm in different strains. It indicated that the differentiation of pathogenicity among the strains of S. sclerotiorum in the test was existed, and the differentiation of pathogenicity might not be related to geographic distribution.