NUTRITIVE VALUE OF TIFTON 85 BERMUDAGRASS AS AFFECTED BY NITROGEN RATES AND REGROWTH AGES

Abstract

The leaf/stem ratio, chemical composition and “in vitro” dry matter digestibility of Tifton 85 bermudagrass as affected by nitrogen rates (0, 100, 200, 300 and 400 kg/ha) and regrowth ages (28, 42 and 56 days) were evaluated. The experimental design was completely randomized with a splitplot feature. The main plots referred to N rates and the splitplots being regrowth ages. The nitrogen fertilization was divided in four parts. Potash fertilization (60 kg/ha K₂O) was also applied after each harvesting. For the whole plant Tifton 85, the CP content increases linearly and positively with the increase of N and decreases linearly and negatively with increasing age of the plant. The ADF and lignin increased linearly and positively with the increase of N and plant age. The increase in cell wall reduces the digestibility of the plant, which has the highest negative correlation with the FDA.