The current system of production of cane sugar, with cultivation of large areas, requires the intensive use of agricultural inputs. Among these, the herbicides are among the most important issues to achieve high levels of productivity today. Among the various options for pre-emergent herbicide registered for the cultivation of sugar cane are the diuron, diuron + hexazinone, metribuzin, and hexazinone. When applied in the culture of sugar cane these pesticides can follow different routes, reaching the ground directly or indirectly. In contact with the ground they can be absorbed by plant roots, are leached, degraded or remain strongly sorbed to the soil. When a molecule of pesticide is sorbed to colloids, it can be in the form of residue on (not available), however, in some cases, part of the fraction bound to the soil can return to the soil solution by microbial processes, this process is known as remobilization.The application of vinasse to fertigation, straw and sugarcane filter cake is widely used in the cane fields, but it is unclear whether this practice leads to remobilization of bound residues and mineralization of herbicides in soil and can bring benefits for the degradation of these herbicides by microorganisms soil, or affect the quality of the soil, leaching to groundwater.Due to the great use of these herbicides and the environmental significance of bound residues of the study, this project aims to evaluate, under laboratory conditions, the remobilization of bound residues of 14C-diuron, 14C - diuron + hexazinone, 14C - 14C and hexazinone - metribuzin in two soil cultivation of sugar cane, which were used known amounts of radiolabeled herbicide treatments with application of stillage, filter cake and straw cane sugar.
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