Desenvolvimento e produtividade de gergelim em latossolo amarelo sob adubação potássica

Abstract

Sesame (Sesamum indicum L.), commonly known as sesame, is recognized for its high nutritional value, with potassium (K) being the second most demanded nutrient by the crop. Due to the expansion of sesame cultivation in the state of Mato Grosso and considering the relevance of fertilization as a significant component of production costs, this study aimed to evaluate the development and productivity of sesame in YELLOW LATOSOL under potassium fertilization. The experiment adopted a 6x4 factorial arrangement, involving six doses of K2O (0, 30, 50, 70, 90, and 120 kg ha-1 ) and four application times (0, 20, 30, and 40 days after sowing). The experimental design was completely randomized, with four replications. At 90 days after sowing, plant height, height of the first capsule insertion, number of nodes, number of branches, number of capsules, capsule mass, and thousand-grain mass were evaluated. At harvest, at 100 days, productivity and plant stand evaluations were conducted, and soil chemical analysis was also performed pre-harvest. No variations were identified in the final plant stand, plant height, height of the first capsule insertion, number of nodes, number of branches, capsule mass, and thousand-grain mass for the dose factor, application times, or their interaction. The application time did not impact the development and productivity of sesame. However, potassium fertilization resulted in significant increases in soil K levels, contributing to increases in both the number of capsules per plant and productivity. The dose that maximized productivity was 90 kg.ha-1 of K2O, providing a grain yield of 718 kg.ha-1.