Variedades de cana forrageira e sucroalcooleira em diferentes espaçamentos e adubação nitrogenada

Abstract

This paper objective is to evaluate the phytomass productivity and bromatologychal attributes of two sugarcane varieties, recommended for animal feed and for sugar-ethanol sector production, planted at two inter-row spacings and submitted to nitrogen fertilization. The experiment was conducted in Presidente Prudente-SP. The experimental design was in split-plot randomized complete block, where plots were installed in the inter-row spacing of 1.0 and 1.5 m, in the sub-plots was installed the sugarcane varieties IAC 86-2480 (forage) and RB 86-7515 (sugar-ethanol sector), and in the sub sub-plots was installed the nitrogen coverage fertilization with 0, 50, 100 and 200 kg ha-1 N. There is no influence of the inter-row spacing, or the variety and nitrogen fertilization on the number of the interril stems m-1 at the harvest. The sugar cane crop planted with 1.0 m inter-row spacing has increased productivity of stems + pointers than the inter-row spacing of 1.5 m. The sugar-ethanol sector variety RB 86-7515 has increased productivity of stems + pointers than forage IAC 86-2480, despite the inter-row spacing and nitrogen fertilization. The phytomass productivity of the forage variety is increased by sugarcane nitrogen fertilization only in 1,0m inter-row spacing, while the sugar-ethanol sector that does not respond to N. The sugar-ethanol sector variety has declined in crude fiber content of the phytomass because of the coverage N doses, however, associated with responsiveness to the inter-row spacing of crop.