Morfogênese do campim faixa-branca submetido a adubação nitrogenada

Abstract

Brazil has a vast area consisting of forage plants, therefore, a large number is at some stage of degradation mainly due to inappropriate choice of the species in relation to the cultivation environment, and as a result, this work took place in order to evaluate the Morphogenesis of White-Band Grass Submitted to Nitrogen Fertilization. The experiment was conducted to evaluate the morphogenetic, structural and productive characteristics of White-Band grass (Digitaria umfolozii) subjected to nitrogen fertilization from January to May 2014. Five doses of nitrogen were evaluated: 0, 100, 200, 300 and 500 kg/ha. The experimental outline was randomized blocks, with four repetitions. Nitrogen fertilization did not affect (P> 0.05) the final length of the leaves, leaf senescence rate, the number of green leaves per tiller, plant height and the ratio of leaf to stem of grass-Range White, presenting, respectively average amounts of 26.9 cm; 0.77 cm / tiller day; 4.2 leaves / tiller; 43.4 cm and 1.04. The appearance and leaf elongation rates, the tiller population density and accumulation of forage, leaves, stems and dead materials of White-Band grass were influenced by nitrogen doses adjusted to a positive quadratic equation (P <0.05) by nitrogen doses. In general, the increase in the amount of nitrogen applied increased the amounts of these rates, reaching maximum points at doses between 300 and 400 kg/ha according to the respective adjusted models. Phyllochron and the lifespan of the leaves were affected in a negative quadratic way (P <0.05) by nitrogen doses. Similarly, the increase in the amount of nitrogen applied declined the values of these rates, reaching minimum points at doses between 300 and 400 kg /ha, according to the respective equations set. The stem elongation rate increased linearly with the nitrogen dose. The White-Band grass has a higher renewal of tissues and productivity when fertilized. The improvement in productive characteristics of White-Band grass reaches maximum amount with nitrogen doses around 300 kg/ha.