FERTILIZACION NITROGENADA Y MOMENTO DE COSECHA DE SEMILLA EN Brachiaria humidicola Stapf.

Abstract

The trial was carried out during 2 years in Granma province, located at 40 m above sea level and on a vertisol soil. The treatments consisted in the application of two nitrogen levels at the beginning of the rainy season (100 and 200 kg/ha), a control with no fertilization, two harvest times in the first year and three harvest times in the second year. A split plot design with three replications was used and the size of the plots was 25 m 2 . In the first year the nitrogen level influenced the number of vegetative stems, fertile stems and length of the racemes, contrary to the rest of the yield components. The highest yields were found at the age of 28 days after the anthesis for all the levels of N and at 21 days and 200 kg of N/ha (P<0,05). In the second year, in addition to the previous components, an increase in the number of racemes, the average length of racemes, the weight of 1 000 seeds and the yield of full seed (P<0,05) was observed. In the second year seed yield increased in the combination 100 N x 28 days (P<0,05). It is concluded that the dose of 100 kg of N/ha may be used at the beginning of the rainy season in order to increase seed yield and harvest between 21 and 28 days after anthesis.