INFLUENCE OF VARIETY, APPLIED NITROGEN AND PLANT-DENSITY ON YIELD AND YIELD COMPONENTS OF SORGHUM, SORGHUM-BICOLOR (L) MOENCH

Trials were conducted at Samaru (in the Savanna zone of Northern Guinea), Nigeria during the 1985-1987 wet seasons to determine the effect of four applied nitrogen levels: 0, 30, 60, and 90 kg N/ha-1 and two plant densities; 50,000 and 75,000 plants ha-1 on yield and yield components of four varieties of sorghum namely: SAMSORG 17, SAMSORG 21, SAMSORG 24 and SOMSORG 25. The result revealed a non-significant influence of variety on mean grain and stover yields, resulting probably from lack of consistent superiority of any of the four varieties over the other in terms of grain yield and yield components. However, the effect of variety on head length, 1000-grain weight, number of days to 50% flowering and shoot height were significant (p < 0.05). The result also revealed high associations (r = 0.85** and r = 0.38**) between head weight and 1000-grain weight with grain yield respectively. It is recommended that an N range of 30-60 kg N ha-1, which gave grain, stover yields and shoot height advantages of 15.6%, 25.3% and 12%, respectively, be applied. The effect of increase of plant density from 50,000 to 75,000 plants ha-1 was significant (p < 0.05) only on stover yield and 1000-grain weight of SAMSORG 21 and SAMSORG 24.