Interference of glyphosate subdoses in the development of young plants of neem.
The regeneration of degraded areas presupposes the planting of forest species in areas that have undergone deep anthropogenic changes and that they are maintained in conditions that allow them to develop rapidly and uniformly. However, problems as presence of weeds can compromise the development of these plants, especially after planting, where they are susceptible to weed competition. One technique widely used to manage it is the use of herbicides. These products can harm and/or kill the plants when hit at high doses, even when the application is performed in a directed jet (drift). One of the widely used herbicide is glyphosate, which is characterized as systemic and not selective. The neem is an introduced species that has been cultivated in Brazil, due to its silvicultural characteristics. This study aimed to evaluate the effect of reduced rates of glyphosate in young plants of neem, aiming to simulate a possible drift. Neem seedlings were treated with 0, 72, 144, 216 and 432 g ha-1 of acid equivalent of glyphosate. The plants phytotoxicity was noticed from 216 g ha-1 of a.e., however, the plants recovered. In these experimental conditions, one can conclude that 0se saplings of neem has hindered its development by the action of glyphosate, However, only from 432 g ha-1 of e.a., the plants suffer significant negative effects by the action of the herbicide.