云南省稻瘟病菌群体的致病性分析及交配型分布

为明确云南省不同稻区稻瘟病菌Magnaporthe oryzae的毒性频率及交配型分布，利用2007—2013年分离自云南省不同稻区的112株稻瘟病菌单孢菌株，对23个持有不同抗性基因的单基因系和持有Pi57(t)的水稻渗入系IL-E1454进行致病性测定。结果表明，稻瘟病菌对不同抗病基因的毒性频率存在很大差异，分离自粳稻区的稻瘟病菌菌株对持有Piz-t、Pi5、Pi9、Pi20和Pi57(t)这5个水稻品系的毒性频率分别为14.29%、5.36%、5.51%、5.36%和0；分离自籼稻区的稻瘟病菌菌株对持有Pik-h、Piz、Pita、Piz-5、Pita-2、Pi5、Pi7和Pi9这8个水稻品系的毒性频率分别为18.25%、9.13%、9.64%、7.50%、15.72%、0、13.05%和0；分离自陆稻区的稻瘟病菌菌株菌株对持有Pik-h、Pib、Pish、Pi1、Pi5、Pi9、Pi11和Pi57(t)这8个水稻品系的毒性频率分别为6.67%、3.33%、13.79%、13.33%、7.69%、6.67%、0和3.23%；交配型测定结果显示，陆稻区菌株可交配率为100.00%，...

Pathogenicity and mating type of rice blast fungus Magnaporthe oryzae isolates in Yunnan Province

In order to understand the virulence frequency and mating type distribution of rice blast fungusMagnaporthe oryzae in different rice-growing regions of Yunnan Province, 112 isolates of M. oryzae collected from different rice-growing regions of Yunnan from 2007 to 2013 were tested on 23 monogenic lines and the introgression line IL-E1454 carrying blast resistant gene Pi57(t). The results indicated that the frequency of M. oryzae isolates virulent to different rice lines showed significant differences. The frequency of M. oryzae isolates from japonica-rice-growing regions virulent to Piz-t, Pi5, Pi9, Pi20 and Pi57(t) were 14.29%, 5.36%, 5.51%, 5.36% and 0, respectively; the frequency of M. oryzae isolates from indica-rice-growing regions virulent to Pik-h, Piz, Pita, Piz-5, Pita-2, Pi5, Pi7 and Pi9 were 18.25%, 9.13%, 9.64%, 7.50%, 15.72%, 0, 13.05% and 0, respectively; the frequency of M. oryzae isolates from upland-rice-growing regions virulent to Pik-h, Pib, Pish, Pi1, Pi5, Pi9, Pi11 and Pi57(t) were 6.67%, 3.33%, 13.79%, 13.33%, 7.69%, 6.67%, 0 and 3.23%, respectively. Determination of mating type with four standard tested isolates showed that all strains from upland rice were fertile, and MAT1-1 and MAT1-2 isolates accounted for 43.33% and 56.67% of total isolates, respectively; the percentage of fertile isolates from japonica rice-growing regions was 91.84%, and MAT1-1 and MAT1-2 isolates accounted for 69.39% and 22.45%, respectively; the percentage of fertile isolates from indica rice-growing regions accounted for 87.88%, of them MAT1-1 and MAT1-2 isolates accounted for 18.18% and 69.70%, respectively. The fertility of M. oryzae isolates was high in different rice areas, but the distribution of their mating types was uneven in some populations.