Rendimento de sementes de azevém anual BRS Integração em função de desfolha e adubação nitrogenada.

Abstract

The annual ryegrass BRS Integration, in the South of Brazil, in hydromorphic soils, differs from the others, especially because it presents high productivity of good quality fodder in a shorter productive cycle. Key feature for integration with hot season crops. However, there is few information on the responses of this cultivar to the management of defoliation and production of high quality seeds. In this sense, an experiment was carried out in the south of Rio Grande do Sul on lowland hydromorphic soils to verify the influence of frequency, defoliation intensity and nitrogen fertilization dose on the production and seed quality of BRS Integration. Two defoliation frequencies (two and three defoliation), two defoliation intensities (7,5 and 15cm height of the residue) were tested and, after the last defoliation, different levels of nitrogen fertilization (50, 100, 150 and 200kg.ha-1). The design was in bands for the fertilization factor and the defoliation maneuvers were randomly allocated within the ranges. The data were submitted to analysis of variance, comparison of means by Tukey test and polynomial regression to describe the nitrogen factor, both at the 5% probability level. The execution of the third defoliation, maintaining 7,5cm of residual height, impairs the yield and the physiological quality of the seed, as well as, the execution of the third defoliation, maintaining 15 cm of residual height, allows high plant response potential for high seed production quality.