Phytorremediation of soil contaminated with sulfentrazone in function of the inoculation of symbotic bacteria in Crotalaria juncea

Abstract

The symbiosis between phytoremediation plants and microorganisms with enzymatic activity that metabolizes herbicides can be an efficient alternative for the remediation of soils contaminated with sulfentrazone. The objective was to evaluate Crotalaria juncea (crotalária) inoculated with Bradyrhizobium sp. in the phytoremediation of sulfentrazone and its effects on soil microbial biomass. The experiment was conducted in a greenhouse at the Universidade Federal do Espírito Santo (UFES), testing four doses of sulfentrazone (0, 400, 800 and 1200 g i.a. ha^-1) in the presence or absence of inoculation with Bradyrhizobium sp. BR2003 (SEMIA 6156). After 65 days of cultivation, the plants were cut, the soil was collected for the analysis of microbial biomass and the bioassay with millet. Inoculation with Bradyrhizobium sp. provided better development in height of the crotalaria plants, however, the root system was not influenced by the addition of the microorganism. The biological indicators of the soil showed that inoculation with Bradyrhizobium sp. negatively influenced soil microbial activity. The crotalaria showed good tolerance to the levels of sulfentrazone in the soil, regardless of the inoculant. The results suggest that inoculation of crotalária with Bradyrhizobium sp. showed no benefit in the efficacy of sulfentrazone remediation, with the crotalaria having a better performance with native soil microorganisms.