大豆胶孢炭疽菌对苯醚甲环唑的抗性机制及其抗性突变体的适合度  

Resistance mechanisms and fitness of anthracnose pathogen Colletotrichum gloeosporioides mutants resistant to difenoconazole

作　　者：石妞妞[1] 阮宏椿[1] 陈文乐 陈巧红 陈福如[1] 杜宜新[1] Shi Niuniu;Ruan Hongchun;Chen Wenle;Chen Qiaohong;Chen Furu;Du Yixin(Key Laboratory for Monitoring and Integrated Management of Crop Pests,Institute of Plant Protection,Fujian Academy of Agricultural Sciences,Fuzhou 350013,Fujiang Province,China;Sanming Plant Protection and Inspection Station,Sanming 365000,Fujian Province,China;Sanming Agricultural Reclamation Station,Sanming 365000,Fujian Province,China)

机构地区：[1]福建省农业科学院植物保护研究所,福建省作物有害生物监测与治理重点实验室,福州350013 [2]三明市植保植检站,福建三明365000 [3]三明市农垦站,福建三明365000

出　　处：《植物保护学报》2022年第4期1022-1031,共10页Journal of Plant Protection

基　　金：福建省属公益项目(2020R10240010);福建省农业农村厅项目(2021PZQS006);福建省人民政府-中国农业科学院农业高质量发展超越“5511”协同创新工程(XTCXGC2021017,XTCXGC2021011);福建省农业科学院农作物重大有害生物灾变机制与绿色防控科技创新团队项目(CXTD2021002-1)。

摘　　要：为明确大豆胶孢炭疽菌Colletotrichum gloeosporioides对苯醚甲环唑的抗性风险及其抗性机制,采用药剂驯化法诱导获得其抗性突变体,并测定抗性突变体的适合度和交互抗性,同时分析抗性突变体和敏感菌株cyp51A和cyp51B基因的cDNA序列、启动区序列及相对表达量。结果表明:从大豆胶孢炭疽菌2株敏感菌株中筛选获得7株低抗苯醚甲环唑的突变体,突变频率为1.75×10^(-4),其抗药性可以稳定遗传。抗性突变体与亲本敏感菌株在对温度的敏感性、菌丝生长速率、产孢量和致病力方面均存在一定差异。苯醚甲环唑与丙环唑之间存在中等交互抗性(相关系数为0.80,P<0.05),苯醚甲环唑与咪鲜胺锰盐、多菌灵、氟啶胺和吡唑醚菌酯之间无交互抗性。抗性突变体cyp51A和cyp51B基因的cDNA序列未发生核苷酸突变,cyp51A和cyp51B基因的启动区无插入片段。经苯醚甲环唑处理后,4株抗性突变体lq27-7-1、lq27-7-2、lq30-2-1和lq30-2-2的cyp51A基因相对表达量被诱导上调倍数显著高于亲本敏感菌株;3株抗性突变体lq27-7-2、lq30-2-2和lq30-2-3的cyp51B基因相对表达量被诱导上调倍数显著高于亲本敏感菌株。表明大豆胶孢炭疽菌对苯醚甲环唑的抗性风险为低至中等,其抗性机制可能与cyp51基因的过表达有关。In order to assess the resistance risk of anthracnose pathogen Colletotrichum gloeosporioides to difenoconazole and clarify the underlying resistance mechanisms,difenoconazole-resistant mutants,which were induced by fungicide-taming method,were studied on the fitness and the cross-resistance.The full-length cDNA of resistance related genes cyp51A and cyp51B,and the promoter sequences were compared between resistant mutants and sensitive isolates,and the relative expression of cyp51A and cyp51B,were also investigated.The results showed that seven mutants with low resistance to difenoconazole were generated from two sensitive isolates,with a mutation frequency of 1.75×10^(-4),and the resistance could be inherited steadily.Mycelial growth responses to temperature,mycelial growth rate,sporulation and pathogenicity differed between the mutants and the sensitive isolates.Moderate level crossresistance was detected between difenoconazole and propiconazole(correlation coefficient was 0.80,P<0.05)in these isolates,but no cross-resistance was observed between difenoconazole and prochlorazMn,carbendazim,fluazinam or pyraclostrobin.Sequence analysis of the full-length cDNA of cyp51A and cyp51B,and promoter region showed that there was no point mutation on all mutants and no inserted fragment in the promoter region.After treatment with difenoconazole,the expression of cyp51A was up-regulated more in four mutants lq27-7-1,lq27-7-2,lq30-2-1 and lq30-2-2 than that in their parent isolates.The expression of cyp51B was also up-regulated more in three mutants lq27-7-2,lq30-2-2 and lq30-2-3 than that in their parent isolates when exposed to difenoconazole.The results indicated that the resistance risk of C.gloeosporioides to difenoconazole is likely to be low to moderate,and the up-regulated expression of cyp51 contribute at least partially to the resistance.

关 键 词：大豆炭疽病 胶孢炭疽菌 苯醚甲环唑 抗性突变体 适合度 抗性机制 

分 类 号：S435.651[农业科学—农业昆虫与害虫防治]