The Detection On Fungicide Resistance And The Research On Resistance Mechanism Of Botrytis Cinerea From Strawberry In Zhejiang Province

Gray mold caused by Botrytis cinerea is one of the major fungal diseases of strawberry in Zhejiang Province, which is considered as one of the most important strawberry-producing areas in China. At present, the chemical control is commonly used and an effective measures on the prevention of grey mould. But, with the longer duration of use and the increase of the dosage, the fungicide resistant of B. cinerea has arised.In our study, a total of486B. cinerea isolates were collected from strawberry in seven locations of Zhejiang Province and we did research on fungicide sensitivity and fenhexamid resistance mechanism of Botrytis cinerea. Results of this study showed that:â‘ The resistance ratio of B. cinerea to carbendazim, pyrimethanil, iprodione and aoxystrobin were65.66%to82.76%, and the proportion of Multiple resistance between them was55.41%, but the resistance ratio of fludioxonil-resistant isolations and boscalid-resistant isolations were5.93%and0.95%, respectively.â‘¡The point mutation D413A on Cyt b (the target protein of aoxystrobin) cause the aoxystrobin resistance of B. cinerea. The aoxystrobin-resistant isolations detected had the mutation, while the aoxystrobin-sensitive isolations did not have.â‘¢There was natural resistance to fenhexamid in B. cinerea with low resistance ratio (11.6%). The mutations existing in sterol3-keto reductase (Erg27, the target protein of fenhexamid) make contribution to the fenhexamid resistance. Seven new mutations were detected for the first time within fenhexamid-resistant isolations and sixty-two (83.8%) isolates of fenhexamid-resistant isolations simultaneously carried the P57A and A378T mutations. The further transformation assays suggested that this two mutations in Erg27were associated with fenhexamid resistance.There has a significant sense of conducting the strawberry farmers to use the fungicides reasonably and making effective control strategies. Furthermore, our study provides a base of future resistance management and the development of new fungicides.