Peng Zhirong, Fu Yuefeng, Wang Fan, Liu Qiqi, Li Yi, Zhang Zhengbing, Yin Li, Chen Xiao-Lin, Xu Jingbo, Deng Huafeng, Xing Junjie
State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha 410125, China.
Yueyang Academy of Agricultural Sciences, Yueyang 414000, China.
J Fungi (Basel). 2023 Jul 23;9(7):776. doi: 10.3390/jof9070776.
Studies on the population structure and variation of in fields are of great significance for the control of rice blast disease. In this study, a total of 462 isolates isolated from different areas of Hunan Province in 2016 and 2018 were analyzed for their population structure and variation tendency. The results showed that from 2016 to 2018, the concentration of fungal races of increased and the diversity decreased; furthermore, 218 isolates in 2016 belonged to ZA, ZB, ZC, ZE, ZF and ZG, with a total of 6 groups and 29 races, in which the dominant-population ZB group accounted for 66.2%; meanwhile, in 2018, 244 isolates were classified into 4 groups and 21 races, including ZA, ZB, ZC and ZG, in which the dominant-population ZB group accounted for 72.54%. In 2018, isolates of ZD, ZE and ZF populations were absent, and the number of total races and isolates of the ZA and ZC groups decreased. Fungal pathogenicity was identified, with 24 monogenic lines (MLs) carrying 24 major genes. The resistance frequency of genes to fungal isolates in 2018 decreased significantly, in which except was 64.5%, the other monogenic lines were less than 50%. Rep-PCR analysis for isolates of Guidong in Hunan also showed that fungal diversity decreased gradually. The influence of genes on fungal variation was analyzed. The pathogenicity of isolates purified from Xiangwanxian 11 planted with monogenic lines was significantly more enhanced than those without monogenic lines. All the results indicated that in recent years, the fungal abundance in Hunan has decreased while fungal pathogenicity has increased significantly. This study will greatly benefit rice-resistance breeding and the control of rice blast disease in Hunan Province.
对田间稻瘟病菌群体结构和变异的研究对于稻瘟病的防治具有重要意义。本研究对2016年和2018年从湖南省不同地区分离得到的462个菌株进行了群体结构和变异趋势分析。结果表明，2016年至2018年，稻瘟病菌生理小种的集中度增加而多样性降低；此外，2016年的218个菌株属于ZA、ZB、ZC、ZE、ZF和ZG，共6个菌群29个生理小种，其中优势菌群ZB组占66.2%；同时，2018年的244个菌株分为4个菌群21个生理小种，包括ZA、ZB、ZC和ZG，其中优势菌群ZB组占72.54%。2018年，ZD、ZE和ZF菌群的菌株缺失，ZA和ZC组的生理小种总数和菌株数减少。对真菌致病性进行了鉴定，用携带24个主效抗病基因的24个单基因系（MLs）进行鉴定。2018年抗病基因对真菌菌株的抗性频率显著降低，其中除Pi9为64.5%外，其他单基因系均小于50%。对湖南桂东菌株的Rep-PCR分析也表明真菌多样性逐渐降低。分析了抗病基因对真菌变异的影响。从种植单基因系的湘晚籼11中纯化得到的菌株致病性比未种植单基因系的菌株显著增强。所有结果表明，近年来湖南稻瘟病菌丰度降低而致病性显著增加。本研究将对湖南省水稻抗病育种和稻瘟病防治大有裨益。
