Aplicação de boro em diferentes estádios da cultura da soja

Abstract

The high global demand for food has encouraged the use of management practices and the use of micronutrients to enhance the productivity of soybeans. This study aims to evaluate the application of boron rates, phenological stages and soybean varieties in components production, productivity and seed physiological quality. Two field experiments conducted in parallel were carried out in 2014/2015 crop in the experimental area of the State University of Goiás, Campus Ipameri. The experimental design used in each of the two experiments was randomized blocks, arranged in a factorial 3 x 5, three phenological stages (V6, V9 and R1) and five doses of boron (0, 1, 2, 3 and 4 kg ha-1), with four repetitions, repeated in two soybean varieties. The following evaluations were performed: leaf boron content, Chlorophyll content, production components, productivity and physiological quality of soybean seeds. The application of boron in different stages did not affect most agronomic components tested both for conventional soybeans as for GM. However, it was effective in increasing the productivity of both varieties studied, regardless of micronutrient application stage. The dose for maximum independent production of the variety studied is 3.51 kg ha-1 of boron. The boron application influenced the physiological seed quality and the stadium more suitable for the application for improvement in the seeds is the V9 and R1 stage, regardless of the variety. Application lower doses than 0,4 kg ha-1 of boron can interfere with the physiological quality of seeds.