贝莱斯芽胞杆菌S297对生菜菌核病的防治效果OA北大核心CSTPCD

Lettuce sclerotinia is a plant disease caused by Sclerotinia sclerotiorum,which mainly affects the stem base of lettuce.In this study,Bacillus velezensis S297 isolated from the previous stage was taken as the research object to investigate its biological control effect on lettuce sclerotinia.The results showed that S297 inhibited the growth of S.sclerotiorum,the formation of sclerotia and germination of sclerotia.The effect of S297 fermentation broth at 5×107 cfu/mL on isolated lettuce leaves infected with S.sclerotiorum reached 84.65%after 36 h treatment.When Bacillus velezensis S297 was mixed with Trichoderma,the control effect was increased to 97.52%,and there was no significant difference between the control effect of 50%Boscalid at 1 mg/mL.In the field experiment,the control efficiency of Bacillus velezensis S297 fermentation broth(5×107 cfu/mL)was 81.08%.The control effect of the combined treatment group of Bacillus velezensis S297 and Trichoderma was 85.14%,and there was no significant difference in the control effect compared to 50%Boscalid at 1 mg/mL.Bacillus velezensis S297 deformed the mycelium of lettuce sclerotinia,and inhibited the activities of polymethylgalacturonases(PMG),polygalacturonases(PG)and cellulose(CL)of Sclerotinia sclerotiorum.Bacillus velezensis S297 also significantly inhibited the production of oxalic acid during the infection of lettuce.