VOLUMES DE CALDA E PONTAS DE PULVERIZAÇÃO NA DESSECAÇÃO EM PRÉ-COLHEITA DA SOJA

Abstract

Soybean is one of the main products of Brazilian agribusiness and for its economic importance different application technologies haven been applied in the development of the crop. The desiccation in pre-harvest with the use of non-selective herbicides has brought many improvements, among them, uniform maturity and ensure the physiological quality of seeds, to anticipate the harvest anticipating the harvest and avoiding losses for deterioration in the field, enabling the implementation of the off-season. The objective of this work was to evaluate different spray volumes associated with the use of different spray nozzles for application of herbicide for desiccation in soybean. The experimental design was in randomized blocks, in split plots, being analyzed two types of nozzles (cone and fan) and different spray volumes (70, 80, 90 and 110 L ha-1). The variables number of drops, spray coverage, radius (CVr), area (CVa), thousand grain weight (g), phytotoxicity score (%) and harvest moisture (%) were evaluated and it is concluded from the results that nozzle type and spray volume do not affect the phytotoxicity and weight of a thousand grains. For the other variables, the cone nozzle showed better performance in the spray volumes of 90 and 110 L ha-1 and the fan nozzle in the spray volumes of 70 and 80 L ha-1.