Dessecantes químicos em pré-colheita da soja na produtividade e qualidade de sementes

Abstract

However, if high rainfall rates, oscillations in the relative air humidity and temperature variations occur during the maturation period, there will be high liabilities in the seed s physiological and pathological quality. An experiment was conducted on the Vovó Palmira Farm, Jardim Olinda PR Brazil and in the Laboratory of Seed Analysis of the Universidade do Oeste Paulista (UNOESTE) so that the ideal moment for the application of desiccating herbicides could be chosen and the viability of harvest anticipation and its effects on yield and physiological quality of soybean seeds could be evaluated. Cultivar BMX Potência RR was planted in the usual manner, with an approximate population of 266,667 plants.ha-1. The experimental design used was a randomized complete block design with five replications in a factorial 2 x 5 + 1, two herbicides applied at 5 different times, totaling 11 treatments with 5 replicates and one witness, a total of 55 plots. The portion adopted as experimental unit consisted of five rows with 5.5 meters long. The results showed that application of Gramoxone data presented more homogeneous, while the Reglone applied to 03 and 06 days have the best results, with the application of herbicides closest to the crop caused a decrease in weight and an increase in the content moisture in the grain, causing reduction in grain quality and requiring greater drying time.Therefore, herbicide application, brought serious problems in the quality of seeds, with abnormal seedlings and dead.The herbicides were effective in the reduction of plant dry matter, thus improving the collection process.