Avaliação do rendimento de híbridos de sorgo granífero sob diferentes doses de nitrogênio em cobertura

Abstract

Grain sorghum has become an important option for farmers in the off­season crop, due to tolerance to water deficit and lower production cost compared to corn, its biggest competitor in the period. However, the average yields obtained still leave something to be desired, largely due to not receiving the proper management to increase their productive potential, such as adequate nitrogen fertilization in coverage. In this sense, the objective of this work was to evaluate the productive performance of four sorghum hybrids (as a function of different doses of nitrogen fertilization in topdressing. The experiment was carried out in the experimental area of the Universidade Tecnológica Federal do Paraná, Campus Dois Vizinhos, in an Oxisol Dystroferric Red The experimental design used was a randomized block design, in a two­factor scheme, with factor A being the sorghum hybrids (S15IO033, B10I002F­X800, 1G100 and 1G233) and factor B being the nitrogen coverage rates (0, 40, 80, 120 kg ha­¹). The morphological and yield components evaluated (plant stand, plant height, dry mass, thousand­grain mass and yield) varied according to the hybrid and the dose. of nitrogen used, except for the variable stem diameter, there was still interaction between the factors for most of the variables.The sorghum hybrid S15IO033 had the highest population, MMG and productivity in tion to the other materials, with a linear increase as nitrogen is supplied in coverage from 0 to 80 kg ha­¹. The material B10I002F­X800 stands out among the others in relation to height and accumulation of dry mass, having also interaction of this hybrid with the dose of N with increase of these variables, as the dose increases from 0 to 120 kg ha­¹. The hybrid 1G233 was the most inferior in relation to the others, with a decreasing behavior with the supply of N in coverage from 80 to 120 kg ha­¹. The hybrids respond to N rates, indicating stability at the rate of 80 to 120 kg ha­¹. The sorghum crop shows promise for adoption in the off­season in the study region.