Effects of nitrogen fertilizer on carbohydrate and protein fractions in pearl millet (<i>Pennisetum glaucum</i>) cultivars

Abstract

Our research characterizes and quantifies carbohydrate and protein fractions of pearl millet (Pennisetum glaucum) cultivars at different nitrogen (N) rates and 2 sowing dates in Ceres, Goiás, Brazil. A randomized block design using 3 cultivars (ADR-7010, ADR-500 and BRS-1501), 4 N rates (0, 50, 100 and 200 kg N/ha) and 2 sowing dates (December 2010 and February 2011) was employed. Two harvests were undertaken for each sowing date, when plants were 0.70 m high. There were no significant differences among cultivars in either total carbohydrates or A+B1, B2 and C fractions of the carbohydrates. Total carbohydrates and their fractions were not affected by N rate nor sowing date. When protein fractionation was investigated, differences in fraction A were observed among cultivars but not in the B1, B2, B3 and C fractions. Nitrogen rate did not affect protein fractions, but sowing date did affect fractions B2 and B3. The significance of these findings in feeding animals is discussed.Keywords: Chemical composition, Cornell Net Carbohydrate and Protein System, forage, nitrogen fertilization.DOI: 10.17138/TGFT(4)47-53