Seleção de espécies cultivadas no verão com potencial de fitorremediar solo contaminado com herbicidas

Abstract

Phytoremediation is a technique that has been used to decontaminate agricultural areas treated with herbicides in an economical, efficient and simple way. Thus, the test of species that present phytoremediation potential becomes important, since new herbicides are launched constantly. Objectives: Evaluate the potential of plant species sown in summer for phytoremediation of soil contaminated with different doses of diuron, sulfentrazone and diuron + sulfentrazone, and also the use of cucumber as a bioindicator plant for depollution. Methods: The experimental design used was completely randomized, arranged in a factorial 8 x 3 (phytoremediating species x doses). Phytotoxicity assessments of cover crops were carried out at 7 and 14 days after emergence (DAE). At 32 DAE, the phytoremediating species were sectioned close to the ground, measuring the leaf area (AF) and dry mass of the aerial part (DM). After determining the AF and DM, cucumber was sown as a bioindicator of herbicide residues in the soil. At 7, 14 and 21 DAE the phytotoxicity was evaluated and at 26 DAE the AF and DM of the cucumber were measured. Results: Signal grass and Sudan grass showed phytoremediation potential in soils contaminated with diuron up to a dose of 980 g ha-1 and diuron + sulfentrazone, up to a dose of 980+490 g ha-1 . Jack bean and Ratrlebox have the potential to phytoremediate soils with sulfentrazone up to a dose of 490 g ha-1 . Conclusions: Pearl millet, Signal grass, Velvet bean and Jack bean have the potential to phytoremediate soils with diuron + sulfentrazone. Sulfentrazone and diuron + sulfentrazone promoted greater toxic effects on the bioindicator plant.