Scarification and doses of Acadian®, Stimulate® and Trichoderma spp. promote dormancy overcoming in Hymenaea courbaril L. seeds?

Abstract: The present study establishes the following research problem: Can different concentrations of Acadian®, Stimulate®, and Trichoderma spp. be effective in promoting the emergence and vigor of Hymenaea courbaril seedlings with or without mechanical scarification? The experimental design used was completely randomized, in a 4 x 3 x 2 factorial scheme, corresponding to four concentrations (0, 5.0, 10.0, and 15.0 mL.L-1), three hormones (Acadian®, Stimulate® and Trichoderma spp.), with and without mechanical scarification, with four replicates, each of which consisting of 25 seeds. Acadian® at a concentration of 5.0 mL.L-1 in scarified seeds of H. courbaril leads to a greater increase in the percentage of emergence and percentage of normal seedlings. Stimulate® at concentrations of 10.0 and 15.0 mL.L-1 is efficient in obtaining more than 85% emergence seedlings with seeds subjected to mechanical scarification. Trichoderma spp. from 9.0 mL.L-1 does not favor gains in the percentage of normal seedlings of Hymenaea courbaril grown from seeds with and without mechanical scarification. The dose of maximum technical efficiency (DMTE) of the bioregulator Acadian® is 8.50 mL.L-1 and, in scarified seeds of H. courbaril, it increases the percentage of seedling emergence.