Efficiency of foliar sulfur supply to soybean in different developmental stages

Abstract

The soybean is a crop with world importance, which grains have several usages in the human and animal nutrition. Among the essential nutrients the sulfur is a macronutrient constituent of proteins and amino acids and is required in appreciable amount by the leguminous crop. The objective of this work was to investigate the effect of sulfur, by foliar application in different developmental stages of soybean, under vegetative characteristics and yield components. The experiment was carried out under field conditions by completely randomized blocks design with four replications, in factorial scheme 3x5 (3 times of foliar application and 5 doses of sulfur). The TMG132RR soybean cultivar was used in this investigation with the doses of 0, 250, 500, 750 or 1000 mL ha-1 of sulfur applied in the stages V2, V2+10 or V2+20 days. The time of foliar application of sulfur has influenced the dry matter of aerial part and the plant height, being the stage V2+20 days the most recommended time. The response to the different doses of sulfur varied based on the results of foliar chlorophyll rate and plant height. For the grain yield there was interaction between time of application of sulfur and dose, being the dose of 731 mL ha-1 applied in V2 stage as the maximum yield of 3,690 Kg ha-1. The yield components number of pod per plant and number of grain per pod were not affected by the times or doses of sulfur application. For thousand grain weight the responses to the different doses varied as the time of application.