Seleção de bioindicadores para monitoramento da mobilidade e persistência de herbicidas aplicados no solo

Abstract

The objective of this work was to select appropriate bioindicators for monitoring the mobility in soil and persistence of amicarbazone, ametryne, diuron and clomazone herbicides. The experiments were conducted in greenhouse conditions, in polyethylene pots of 250 cm 3 with dystroferric Red Latosol. In each experiment, it was used one herbicide (amicarbazone, ametryn, diuron or clomazone) and three bioindicators (10 seeds of each specie), distributed in randomized blocks design in a factorial scheme 5 x 3, with three replications. Studied factors were herbicides rates (0; 12.5; 25; 50 and 100% of recommended rate of each herbicide) and species used as bioindicators ( Cucumis sativus, Brachiaria decumbens e Sorghum bicolor ). Thirty days after sowing, aerial parts of plants were cut and kept in a forced air oven at 40 °C in order to determine dry matter. Among bioindicators species tested, C. sativus was the one that had the highest sensitivity to the concentrations of amicarbazone and ametryne applied in soil. B. decumbens also had an appropriate response for biomonitoring clomazone and diuron, evidencing this idea for further experiments of mobility and persistence in clay soil. S. bicolor specie had the lowest inhibition of biomass among the bioindicators for all herbicides evaluated, therefore not indicated to evaluate the behavior of these herbicides in soil.