安徽省水稻条斑病菌种群的分离及其致病型监测

为了探明安徽省水稻条斑病菌种群的致病类型及分布情况，采用平皿稀释法对采自安徽省不同地区的水稻条斑病叶进行了病原细菌分离，通过PCR专化性检测方法对细菌分离物进行分子鉴定，并利用IRBB5、IRBBl4、IR24、IRBB4、IRBB21和‘金刚30’等6个水稻鉴别品种，对获得的水稻条斑病菌种群进行了致病型监测。结果表明，从安徽省11个不同县市的水稻条斑病样中共获得72株水稻条斑病菌，来源于不同地区的水稻条斑病菌种群存在明显毒力分化，强毒性菌株和弱毒性菌株并存，且多数菌株与水稻品种间表现为弱互作关系，部分菌株与寄主存在强互作模式。依据其毒力差异可将其划分为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ等6个致病型。从本研究结果可以看出，安徽省水稻条斑病菌种群致病型分化明显，且水稻条斑病菌种群的毒力与地域分布具有一定的相关性。

Isolation and Pathotype Monitoring of Xanthomonas oryzae pv. oryzicola Population in Anhui Province

In order to ascertain pathotypes of Xanthomonas oryzae pv. oryzicola population and their distribution in Anhui Province, bacterial isolates were recovered from diseased leaves of rice plants associated with bacterial leaf streak located in different regions in Anhui Province using the plate dilution methods, and strains of X. oryzae pv. oryzicola were identified by PCR detection. With six differential rice varieties （IRBB5, IRBB14, IR24, IRBB4, IRBB21 and ‘Jingang30＇）, the virulence differentiation of X. oryzae pv. oryzicola population was identified by the inoculation methods of leaf-needling at adult stage. The results showed that a total of 72 bacterial isolates were obtained and identified as X. oryzae pv. oryzicola, and there were significant difference of virulence among these strains of X. oryzae pv. oryzicola from different regions in Anhui Province. The strains with strong virulence and weak pathogenicity existed in the population of the pathogen, and most strains were found weak interaction between bacterial strains and rice varieties, but the minority of the strains was specific interaction significantly. Six pathotypes （ Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ and Ⅵ） were classified according to their virulence differences on 6 differential rice varieties. It can be concluded that the virulence difference was obvious among X. oryzae pv. oryzicola population in Anhui Province, and the virulence of X. oryzae pv. oryzicola population was relative to the origin of strains.