Selectivity of Herbicide 2,4-D, Isolated and In Association, In Pre-Emergency in Culture of Açaí

With the growth of acai planted areas, further studies on herbicides are needed in this palm tree of great potential. Thus, the present work aimed to evaluate the selectivity of the 2,4-D herbicide applied in pre-emergence, isolated, and in association, with acai seedlings. The experimental design was randomized blocks with 4 replications. Increasing doses of 2,4-D isolated (502.5, 1,005 and 2,010 g e a ha) and associated with picloram (960 g e. a ha), triclopyr (960 g e. a ha) were applied as treatments. and glyphosate (1,110 g e. a ha), one more control without application. At 3,7,14,21,28 and 35 DAA, the percentage of phytointoxication, height (cm), and the number of leaves of the acai seedlings were determined. At the end of the evaluations (35 DAA), the 2,4-D isolated applications obtained the best results, with low phytointoxication visual percentage, higher plants, and a larger number of leaves, showing selective culture. However, the association of the 2,4-D herbicides with picloram, in all doses used, had negative effects on the evaluated parameters, evidencing the non-selectivity of the acai berry crop