GROWTH PARAMETERS AND FORAGE YIELD OF TWO GRAIN SORGHUM (Sorghum bicolor L. Moench) VARIETIES UNDER DIFFERENT PLANTING DATES AND AGES OF HARVEST IN SHIKA

Abstract

To determine the influence of sorghum variety, planting dates and ages of harvest on growth parameters and forage yield of grain sorghum (Sorghum bicolor L. Moench) in Shika, Nigeria, an experiment was conducted in split plots in the National Animal Production Research Institute, Shika, Nigeria. The experimental treatments comprised of two sorghum varieties (SAMSORG-16 as V1 and SAMSORG-17 as V2), three planting dates (15th June, 30th June and 14th July as P1, P2 and P3) and three ages of harvest (6, 10 and 14 weeks after sowing as C1, C2 and C3), respectively. Results showed that plant height of sorghum bicolor significantly (P<0.05) differed between variety with higher values in Samsorg-16. Plant height, number of leaves and leaf area index (LAI) decreased (P<0.05) from 15th June to 14th July planting date. However, there was a significant increasing trend (P<0.05) in these parameters as ages of harvest advanced from 6 to 14 week after sowing (WAS). Significant (P<0.05) interaction effect between variety and planting date was observed for plant height. Similarly, significant (P<0.05) interaction effect was observed in the number of leaves and LAI. There was non-significant (P>0.05) effect of variety on fresh and dry forage yields. Fresh and dry forage yields declined from 54.73 and 10.49 t/ha to 30.72 and 6.11 t/ha from 15th June to 14th July planting dates, respectively. Whereas fresh and dry forage yields increased from 12.22 and 1.37 t/ha to 58.94 and 14.47 t/ha as ages of harvest increased from 6 to 14 WAS,