Reduced spacing for Sorghum bicolor in the irrigated and rainfed systems

Abstract

The water stress in the North of Minas Gerais enabled sorghum (Sorghum bicolor L.) to arise as a good option for the region. This culture tolerates better the high temperatures and water deficit when compared to most of the other cereals. Due to the importance of the sorghum crop in that region, the aim of this work was to determine the best arrangement of plants in the sorghum under irrigated and rainfed system. Two experiments were conducted in adjacent areas with an irrigated and rainfed system. In each experiment, it was used the densities of 100, 150, 200 and 250 thousand plants ha^-1, and the spacing of 25, 50 and 75 cm. Each experiment was conducted under a randomized block design, in a 4 x 3 factorial design with four replications, with four densities and three spacing. The data were initially submitted to an analysis of variance. This was followed by an analysis of variance involving the two experiments. The reduction of spacing between rows promotes increases in grain yield, regardless of plant population adopted. Sorghum grown under irrigation has increased productivity by reducing the spacing, however, the increase in population of plants in irrigated provides increases in productivity to a point of maximum, and decreased under.