Study On The Distribution Of Resistant Mutantion To Main Fungicides And The Mechanism Of Multi-drug Resistance Of Botrytis Cinerea In China

Management of gray mould,caused by Botrytis cinerea,has largely depended on chemical funficides.However,the efficacy of fungicides has been decreased by the emergence of resistant isolates.In this study,1106 isolates of Botrytis cinerea collected from vineyard in 6 locations in China,include Harbin,Heilongjiang province,Beizhen,Liaoning province,Penglai,Shandong province,Taigu,Shanxi province,Jingzhou,Hubei province and Binchuan,Yunnan province,to detect the frequency and distribution of resistant mutations to carbendazim,iprodione and boscalid,and detect the sensitivity to fludioxonil.The main results of this study are as follows: 1.The resistance mutantion types and distribution of B.cinerea in China to carbendazim,iprodione and boscalid were identified.Resistant mutations of B.cinerea to carbendazim,iprodione and boscalid were detected by sequencing their target gene.Results showed: 1)The resistance frequency and level of B.cinerea in China to carbendazim were very high.The resistant mutants were E198 A and E198 V on geneβ-Tubulin.E198 A was the major mutation in north area,while the frequency of E198 V mutation was relatively high in south area.Rapid detection techniques can be developed based on the above two mutation types to monitor the resistance of B.cinerea to carbendazim in China.2)The resistance frequency of B.cinerea in China to iprodione was prety high.The resistant mutants were I365N/S,Q369P+N373S and Q369 P on gene BosI,and the major mutations were I365N/S.Frequency of I365 N mutation in Harbin,Heilongjiang province was much higher than I365 S,while frequency of I365 N mutation in Binchuan,Yunnan province was much lower than I365 S.The mutant sites I365N/S and Q369 P can be used as target sites to develop rapid detection techniques for the monitoring of resistance of B.cinerea to iprodione in China 3)The resistance frequency of B.cinerea in China to boscalid was relatively low.Resistant mutantations were H272R/Y/L,P225F/L/T and N230 I on gene SdhB,and the major mutations were H272R/Y.Rapid detection techniques can be developed based on H272R/Y mutation types to monitor the resistance of B.cinerea to boscalid in China.4)There were 8 multidrug resistance types of B.cinerea in vineyard in China to carbendazim,iprodione and boscalid.Strains with double resistant to carbendazim and iprodione,and strains with triple resistant to carbendazim,iprodione and boscalid accounted for the majority of the total strains.2.Sensitivity of B.cinerea to fludioxonil in China and the relationship between the mutation found on mrr1 gene and MDR1 type multidrug resistance were identified.Sensitivity of 372 B.cinerea to fludioxonil was detected by mycelium growth method.According to the results,no fludioxonil-resistant strain was detected and the sensitive baseline of B.cinerea in vineyard in China to fludioxonil was 0.007(±0.004)μg/mL.No MDR1 strains of B.cinerea in vineyard in China was detected.Mutations of I443 L and H353 D on the mrr1 gene of MDR1 strains which have been reported as well as 22 new mutation sites newly detected in this gene in our laboratory could not cause MDR1 type multidrug resistance.The results of this study can provide theoretical support for the establish of fast molecular detection method of fungicides resistance of B.cinerea in vineyard in China and provide guidance for the selection of effective fungicides in production.