Avaliação da produtividade de soja em função da forma de aplicação de cloreto de potássio e super fosfato triplo

Abstract

Soybean (Glycine max) is the main commodity produced in the world and one of the most important sources of protein in food and feed. The optimization of its production is based on a series of fundamental pillars, among them the fertilization is highlighted as being the basis for a good development of the plant. Considering this scenario, the present work aims to evaluate the productivity, the rate of emergence speed, stem diameter, severity of Asian rust and the weight of one thousand grains of the soybean crop submitted to fertilization to the haul and to the seeding line. The experiment was carried out in the municipality of Cerro Largo - RS, in the agricultural year of 2015/2016 in the experimental area of the Universidade Federal da Fronteira Sul - Campus Cerro Largo, in a typical dystroferric Red Latosol. The experimental design was a randomized block with 5 treatments and 4 replicates, totaling 20 plots. The treatments were as follows. Treatment 1: control (without fertilization); Treatment 2: 275 kg / ha of triple super phosphate and 95 kg / ha of potassium chloride in the line; Treatment 3: 275 kg / ha of triple super phosphate in the line and 95 kg / ha of potassium chloride in the haul; Treatment 4: 275 kg / ha of triple super phosphate in line 95 kg / ha of potassium chloride in the haul; Treatment 5: 275 kg / ha of triple super phosphate to the haul and 95 kg / ha in the line. The data were analyzed and all means of the variables were compared by applying the Tukey test to 5% probability in the Assistat version 7.7 program. Only the control presented lower productivity, differing statistically from the other treatments. The severity of Asian rust was lower in Treatment 5, which, under the study conditions, was not influenced by the treatments. The weight of a thousand grains, stem diameter and the rate of emergence did not differ, regardless of the way the fertilization was carried out.