[Effects of applying endophytic fungi on the soil biological characteristics and enzyme activities under continuously cropped peanut].

A pot experiment was conducted to investigate the effects of applying endophytic fungi Phomopsis liquidambari strain B3, Phomopsis sp. strain NJ4.1, and Ceratobasidum stevensii strain B6 on the soil biological characteristics and enzyme activities under continuously cropped peanut at its different growth stages. Compared with the control, applying B3 increased the peanut yield significantly by 19.8%, and applying NJ4.1, B3 and B6 increased the peanut nodule number significantly by 20.4%, 29.3% and 27.6%, respectively. In the three treatments of applying endophytic fungi, the average population of soil bacteria and actinomycetes in the whole growth period of peanut was higher than that of the control, and the soil microbial biomass carbon was significantly greater at germination and seedling stages. The soil microbial biomass nitrogen increased at germination stage, but decreased at flowering stage. The DGGE analysis indicated that at flowering stage, the soil bacteria and fungi in treatment B3 had the largest band number and diversity. From germination stage to maturing stage, the three treatments of applying endophytic fungi had higher activities of soil invertase and catalase than the control, but less difference in soil urease activity. It was suggested that applying endophytic fungi could improve the peanut continuous cropping soil environment, and applying B3 had the best effect.