INFLUENCE OF SPLIT-APPLIED NITROGEN ON GRAIN-YIELD AND PROTEIN-CONTENT IN 10 GRAIN-SORGHUM CULTIVARS

More information on the response of newly developed or introduced grai n sorghum cultivars to split-applied nitrogen (N) in semi-arid rainfed agriculture is needed. Therefore, the influence of four split-applied N schedules (100/0, 66/34, 50/50, and 34/66) on six American (SC 283, SC 274, SC 669, B 66181, SC 33, and RTam 428), and four West African (CSm 63, IS 6704c, 1S 7173c, and 1S 7419c) grain sorghum cultivars was evaluated. The split-applied N significantly increased grain yield an d percent protein in grain sorghum over a one-time application of N. T he increase in yield and protein content varied among varieties and sc hedules of N application. Varieties SC 574, RTam 428, and Csm 63 at sp lit-applied schedules of 66/34, 50/50, and 34/66, respectively, gave t he highest yield over one-time application of N. Similar differences i n percent protein in grain among cultivars due to split-applied N were observed.