Production potential of fodder sorghum (Sorghum bicolor) varieties under different nitrogen levels and sowing dates

Abstract

A field experiment was conducted during 1996-98 at Jhansi, to find out the productivity of 3 sorghum [Sorghum bicolor(L.) Moench] varieties ('HC 171', 'JS 10' and 'HD 15') at low, mediuma nd high fertility levels (40,80 and 120 kg N/ha) and early, medium and late planting conditions (beginning, mid and end of July). Analysis of 3 years mean data indicated that plant height, number of green leaves, leaf and stem weight/plant were significantly superior in 'HD 15'(244 cm, 9.9/plant, 85.9 and 287.1 g/plant, respectively), sowing in beginning of July and 120 kg N/ha. However, plants/m and leaf:stem ratio of different varieties did not differ significantly. These characters were at par with 80 and 120 kg N/ha. The highest green fodder (39.7 tonnes/ha), dry matter (7.6 tonnes/ha) and crude protein (510 kg/ha) yields were obtained in 'HD 15'. Forage and crude protein yields were significantly higher when crop was sown in the beginning of July. Significant increase in green fodder (5.9 tonnes/ha) and dry matter (0.94 tonne/ha) yields were recorded when nitrogen level increased from 40 to SO kg/ha. Further, increase in nitrogen levels could not increase the yields significantly. however crude protein yield increased significantly up to 120 kg N/ha. Interactions between varieties and sowing dates, varieties and nitrogen levels, and nitrogen levels and sowing dates were found significant.