Sensitivity of Eucalyptus Clones to Herbicides Associated with Foliar Fertilizers

Abstract

Postemergence application of herbicides can cause phytotoxicity problems in eucalyptus seedlings. Foliar fertilization can improve seedling development and mitigate the effects of herbicides on eucalyptus. Thus, the objective of this work was to evaluate the sensitivity of eucalyptus clones subjected to herbicides applied postemergence and associated with the application of foliar fertilizer. For this, a field experiment was carried out with the application of the products indaziflam, clomazone, glyphosate + S-metolachlor, sulfentrazone, and diuron + sulfentrazone, plus the application of an additional foliar fertilizer (composition in g/L of 78, 13, 40.3, 1.17, 0.78, 16.9, 13, 14.3, 0.52, and 29.9, respectively, for C, N, S, B, Co, Fe, Cu, Mn, Mo, and Zn). Height, stem diameter, shoot dry mass, chlorophyll content, and visual intoxication were the analyzed variables. The herbicides indaziflam and glyphosate + S-metolachlor were the most harmful to the tested eucalyptus clones, interfering with the growth variables. Among the evaluated clones, Clone AEC 144 had more significant changes in the analyzed variables in treatments with herbicides and foliar fertilizer application. The eucalyptus seedlings were generally more sensitive to indaziflam and glyphosate + S-metolachlor herbicides. Foliar fertilization reduced the intoxication caused by indaziflam in Clone AEC 056. The fertilizer intensified treatment symptoms with clomazone and diuron + sulfentrazone in Clone AEC 144 and with sulfentrazone and diuron + sulfentrazone in Clone AEC 2034.