北疆棉花黄萎病发病率调查及土壤中黄萎病菌微菌核数量与种群类型分析

Investigation on the incidence rate of Verticillium wilt and analysis on the number of microsclerotia and the population type of Verticillium dahliae in soil of Northern Xinjiang

为了解北疆棉花黄萎病的发生情况及发病与土壤中黄萎病菌微菌核数量的关系和病原菌种群类型,2021年对北疆石河子、奎屯、博乐等8市(县)棉田棉花黄萎病发病率、土壤中黄萎病菌的微菌核数量、菌株种群类型进行了抽样调查。结果表明,北疆未发生棉花黄萎病的棉田占49.2%,0%<发病率<5.0%的棉田占32.7%,发病率≥5.0%的棉田占18%。与2013年、2015年相比,2021年无病田率分别增加17.7和12.7百分点,发病率≥5%的棉田分别减少15.7和21.6百分点。从棉田黄萎病发病率与土壤中微菌核数量的关系来看,整体上北疆棉田棉花黄萎病发病率与微菌核数量相关性不显著(r=0.1191);分区域看,石河子沙湾片区、奎屯乌苏片区、精河博乐片区棉田黄萎病发病率与微菌核数量的相关系数分别为0.0332、0.0076、0.0623,均无显著相关性;而呼图壁玛纳斯片区棉田黄萎病发病率与微菌核数量的相关系数为0.6357,呈中度正相关。土壤中的黄萎病菌菌株以菌核型为主,占57.9%,菌丝型占23.2%,中间型占18.9%。用特异性引物进行PCR检测表明,土壤中黄萎病菌落叶型菌株占97.6%,占绝对优势。本研究将为北疆棉区棉花黄萎病的综合防控提供理论依据。

In order to find out the occurrence of cotton Verticillium wilt,the number of microsclerotia and the population structure of Verticillium dahliae in soil in northern Xinjiang,the incidence of Verticillium wilt,the number of microsclerotia of V.dahliae in soil,the growth types of V.dahliae and the proportion of defoliating strains were investigated in eight cities(counties)of northern Xinjiang in 2021,such as Shihezi,Kuitun,Bole,and so on.The results showed that the Verticillium wilt disease-free field accounted for 49.2%,the disease field with the 0%<incidence<5.0%,accounted for 32.7%,the serious disease field with the incidence of more than 5.0%accounted for 18%.Compared with 2013 and 2015,the disease-free field rate in 2021 increased by 17.7 percentage and 12.7 percentage respectively,and the cotton field with incidence of more than 5%decreased by 15.7 percentage and 21.6 percentage,respectively.From the relationship between the incidence and the number of microsclerotia in cotton field,overall,there was no significant correlation between the incidence of Verticillium wilt with the number of microsclerotia of V.dahliae in soil(r=0.1191).By region,the correlation coefficients between the incidence of Verticillium wilt and the number of microsclerotia were 0.0332,0.0076 and 0.0623 in Shihezi-Shawan area,Kuitun-Wusu area and Jinghe-Bole area,respectively,with no significant correlation.There was a moderate positive correlation between the incidence of Verticillium wilt and the number of microsclerotia in Hutubi-Manas area(r=0.6357).The growth types of V.dahliae strains in soil were mainly sclerotia type(57.9%),mycelium type(23.2%),intermediate type(18.9%).PCR with specific primers showed that the proportion of defoliating strains was 97.6%,which dominated absolutely.This study will provide a theoretical basis for the comprehensive prevention and control of Verticillium wilt in cotton areas of northern Xinjiang.