A field experiment was conducted during rainy (kharif) seasons of 2000–02 at Jhansi to know the response of fodder sorghum [Sorghum bicolor (L.) Moench] to nitrogen levels and weed-control techniques. Significant increase in green-fodder, dry-matter and crude-protein yields was recorded with successive increase in nitrogen up to 60 kg/ha. N at 60 kg/ha gave significantly higher green-fodder (45.2 t/ha), dry-matter (8.26 t/ha) and crudeprotein yields (646.7 kg/ha) as well as nitrogen uptake (104.2 kg/ha), but at higher level showed no significant differences. However, 90 kg N/ha gave the highest net profit (Rs 15,850/ha) and benefit: cost (B:C) ratio (1.55) compared with the remaining levels. Among weed-control techniques, broadcast sowing of cowpea (Vigna unguiculata (L.) Walp.) and application of atrazine @ 0.5 kg/ha were at par and gave significantly higher greenfodder (52.1 and 49.1 t/ha) and dry-matter (8.9 and 9.06 t/ha) yields than other techniques. Broadcast sowing of cowpea gave higher net profit (Rs 13,800/ha), B:C ratio (1.45) and significantly higher crude-protein yield (800 kg/ha) as well as nitrogen uptake (126.2 kg/ha) than others methods. Atrazine 0.5 kg/ha gave significantly lower weed density (25.6/m2), dry weight of weeds (0.30 t/ha) and nitrogen uptake by weeds (4.0 kg/ha) than other techniques. This was closely followed by broadcast sowing of cowpea, registering 104.5/m2, 1.93 t/ha and 16.3 kg/ha respectively. Interaction effects of nitrogen levels and weed-control techniques for green-fodder, dry-matter, crude-protein yields and nitrogen uptake of sorghum were also significant.
Forage sorghum, Green fodder, Crude protein, Nitrogen uptake, Weed-control techniques
