Objective The study was carried out to verify the application effect and safety of carbendazim degrading strain Alternaria compacta WJD-55 in greenhouse soil.

Method Carbendazim was added to the greenhouse soil and microbial agent W55 made with WJD-55 were applied at same time, and tomatoes were cultivated for observation. The changes of the remaining carbendazim, colonization of WJD-55 and soil fungal community, soil physical and chemical properties and planting growth of tomatoes were monitored during 50 days of remediation, with a view to evaluate the application effect of microbial agent W55 and its safety.

Result The carbendazim content in initial soil about 42 mg/kg and the application amount of the agent was 0.1%. After treatment for 10 days, carbendazim residual was 9.27 mg/kg, with a decrease of 78%. While in control soil, carbendazim residual was about 30.2 mg/kg, with a decrease of 29%. There was extremely significant difference(T-test, P=0.001)between two groups. High throughput sequencing of soil microorganism showed that WJD-55 could colonize in soil stably, which rescued the negative impacts of carbendazim on microbial diversity. The physical and chemical indexes of soil showed the microbial agent W55 had no significant effect on soil physical and chemical properties. The growth of tomato plant was not affected by the agent and WJD-55 showed no harm to the tomato leaves.

Conclusion Alternaria compacta strain WJD-55 could colonize stably in soil and degrade carbendazim effectively, decrease the carbendazim content in soil rapidly, improve the fungal microorganism diversity of the contaminated soil, and has no negative effect on soil and plant.