EFFECTS OF WEED CONTROL AND COW DUNG MANURE ON GROWTH INDICES OF QUALITY PROTEIN MAIZE

Field trials were conducted during the 2006, 2007 and 2008 rainy seasons at the Institute for Agricultural Research farm Samaru, in the Northern guinea savanna zone of Nigeria to evaluate the effects of weed control and cow dung manure treatments on growth of quality protein maize. The trials consisted of factorial combinations of eight weed control treatments which include application of proprietary mixtures of (Atrazine + Acetochlor + Terbuthylazine at a ratio of 1:1:1, Atrazine + Metolachlor at a ratio of 1:2 each at 3.0 and 4.0 kg a.i/ha, Atrazine at 4.0 and 5.0 kg a.i/ha, Hoe weeded at 3 and 6 weeks after sowing and a weedy check) with four cow dung manure levels at (0, 4, 8 and 12 t/ha and a recommended NPK mineral fertilizer check at the rate of 120 kg N, 26 kg P and 50 kg K/ha. The treatments were laid out in a split plot design with three replicates. Results indicated that application of Atrazine + Metolachlor at 4.0 kg a.i/ha and the two hoe weeded produced significantly (p>0.05) higher and similar values of 140.2 and 137.3 grams respectively for total dry matter with 11.1 and 11.8 g/m2/week respectively for crop growth rate. Plots treated with Atrazine + Metolachlor at 4.0 kg a.i/ha recorded significantly the highest values of 3.05 for leaf area index and 0.41 for harvest index. Application of Atrazine + Acetochlor