广西稻瘟病菌生理小种鉴定及遗传多样性分析

摘要

[Objective] The present paper aims to figure out physiological races variation and genetic structure of Magnaporthe oryzae in Guangxi and providea basis for breeding and distribution of rice resistant varieties in the future.[Method] Physiological races identification with seven differential varieties and genetic diversity analysis with SSR of M.oryzae from 2012 to 2014 in Guangxi were conducted in the present work.[Result]24 physiological races belonging to 7 groups which included ZA,ZB,ZC,ZD,ZE,ZF and ZG were identified from 142 isolates collected from 2012 to 2014.Among them,the predominant group was ZB with an occurrence frequency of 67.61％,and the predominant races were ZB9and ZB13 with an occurrence frequency of 19.01％,respectively.The UPGMA method was used to analyze the genetic diversity of 107 isolates and 14 lineages at similarity coefficient of 0.88 were obtained.Among them,lineage L01 was the dominant lineage accounting for 44.86 ％ of the isolates,lineage L03,L06 and L11 were subordinate lineages accounting for 19.63 ％,13.08 ％ and 10.28 ％ of the isolates,respectively.In addition,the number of isolates and their corresponding physiological race of every lineage was counted and the result showed that there was no correlation between genetic lineages and races.[Conclusion] Between the year of 2012 and 2014 in Guangxi,the predominant group of M.oryzae was ZB while the predominant races were ZB9 and ZB13,and there was no correlation between genetic lineages and races.%[目的]明确广西稻瘟病菌生理小种组成及遗传结构,为今后水稻抗病品种的选育和布局提供依据.[方法]利用我国7个稻瘟病菌鉴别品种和SSR对广西2012～ 2014年分离获得的稻瘟病菌单孢菌株分别进行生理小种鉴定和遗传多样性分析.[结果]2012-2014年分离获得的142株稻瘟病菌菌株分成ZA、ZB、ZC、ZD、ZE、ZF、ZG 7群24个生理小种,其中优势种群为ZB,出现频率67.61％,优势生理小种为ZB9和ZB13,出现频率均为19.01％.运用UPGMA法对其中107个菌株进行遗传多样性分析,在0.88的相似水平上划分为14个遗传宗谱.其中,宗谱L01为优势宗谱,占供试菌株比例为44.86％;其次为宗谱L03、L06和L11,占供试菌株比例分别为19.63％、13,08％和10.28％.对每个遗传宗谱所包含的菌株及对应生理小种进行统计,发现稻瘟病菌遗传宗谱与生理小种之间未存在相关性.[结论]2012-2014年广西稻瘟病菌优势种群为ZB,优势生理小种为ZB9和ZB13,其遗传宗谱与生理小种之间未存在相关性.