Changes in Microbial Community and Activities in Continuous Pepper Cropping Soil After a Trichoderma Hamatum MHT1134 Application

Abstract To clarify the control effects of strain MHT1134 on Fusarium wilt in continuous pepper cropping fields and its regulatory effects on soil microecology, the physical and chemical properties, enzyme activities, community structures of soil samples from five field types were analysed. Samples were taken from fields in their 1st, 5th and 9th planting years, and at 1 and 2 years after the application of strain MHT1134 in 9th planting year field. The MHT1134 control effects on pepper wilt after 1 and 2 years were 63.03% and 70.21%, respectively. 4 kinds of physical and chemical indexes and 6 kinds of enzyme activities in soil were increased. With the continuous cropping years increased, the microbial abundance and diversity decreasing significantly. The relative abundances of Fusarium, Gibberella increased along with the planting years, but decreased after the MHT11134 application. However, the relative abundances of Trichoderma and Chaetomium significantly increased. Additionally, as the cropping years increased, the soil abundance of Actinobacteria gradually decreased, but it significantly increased from 17.56% to 22.44% after the MHT1134 application. Thus, strain MHT1134 effectively improved the microbial community structure of the soil, and it also positively affected soil quality. A continuous application may improve the control effect.