Densidade de semeadura e desempenho de arroz híbrido irrigado

Abstract

The use of hybrid presents itself as an alternative to the increase in average productivity of irrigated rice in the country. However, the cost of seed production is still higher than the conventional cultivars, due to technology involving the production of hybrid seeds and their specificities. Due to the effect of plasticity that hybrids have, has studied the possibility of reducing the seeding rate to further lower densities without affecting the productivity and quality of grain. The aim of this study was to evaluate the effect of reducing the seeding rate on yield and quality of grain in two hybrid rice. The experiments were conducted in the municipalities of Capão do Leão and Capivari do Sul, in Rio Grande do Sul. The treatments were composed by hybrid BRS CIRAD 302 and H4 CL, in sowing densities 10, 20, 30 and 40 kg ha-1 with three replications. Among the variables are productivity, rice yield components, agronomic characteristics, industrial and commercial quality of rice grains. Data were subjected to analysis of variance and F test at 5% probability. When F was significant for hybrids factors and plant density, we used the 5% Tukey test for the qualitative factor and polynomial regression for the quantitative factor. In conclusion it was determined that from the seeding rate of 20 kg ha-1, there is no effect of seeding rate on yield of both hybrids of rice. The grain quality of the hybrid is not influenced by variation in plant density and reducing the seeding rate up to 10 kg ha-1 did not affect the commercial quality of the grains of rice hybrids.