TECHNIQUES FOR GROWING SIDEOATS GRAMA (Bouteloua curtipendula) SEEDLINGS IN GREENHOUSE FOR TRANSPLANTATION

Mismanagement of pastures in semi-arid areas has resulted in the loss of forage plant species that limit livestock productivity. One strategy to improve vegetation cover with grass is to develop seedlings in greenhouse for subsequent transplantation at the beginning of the rainy season. The objective of this study was to evaluate the combination of substrates on the growth of seedlings of sideoats grama (Bouteloua curtipendula) in greenhouse and the survival of seedlings to the effect of agrochemicals for the control of broad-leaved weeds. A completely randomized design was used in factorial arrangement to evaluate 13 substrate combinations and their effects on plant height, leaf area and morphological composition, as well as seedling survival after the application of 2,4-D amine, 2,4-D ester and atrazine at 1000, 1500 and 2000 g of active ingredient (a.i.) in 200 L water at 14, 19, 23, 28 and 32 days after sowing. Analysis of variance and comparison of means with the Tukey test (P = 0.05) were carried out. The simplest and most effective combination in the development of seedlings was soil + gravel 3:1, but in the same way organic matter can be incorporated as sheep or rabbit precompost at 1/3. At younger age of sideoats grama seedlings there is more damage due to the effect of herbicides for broad-leaved weeds and the most harmful combination was 2000 g i.a. of 2.4-D amine + atrazine, so it is recommended to apply 2.4-D amine or 2.4-D ester at 1000 g a.i. up to 23 days after sowing.