Indian Journal of Agronomy

A field experiment was laid out during the rainy seasons of 2008 and 2009 at Udaipur, Rajasthan, to evaluate effect of fertility levels, nutrient sources and weed control on productivity of quality protein maize (Zea mays L.). Twenty seven treatment combinations comprising 3 fertility levels (90 kg N + 40 kg P₂O₅, 120 kg N + 50 kg P₂O₅ and 150 kg N + 60 kg P₂O₅/ha), 3 nutrient sources (100% NP through fertilizers, 75% NP through fertilizers + 25% through vermicompost and 50% NP through fertilizers + 50% through vermicompost) and 3 weed-control measures (weedy check, metribuzin 0.4 kg/ha followed by (fb) hoeing and weeding and atrazine 0.4 kg + alachlor 2.0 kg/ha fb hoeing and weeding) were tested in split-plot block design with 3 replications. Weed density was not affected by fertility levels but the total weed dry matter increased significantly up to 120 kg N + 50 kg P₂O₅/ha at 30 days after sowing (DAS) and up to 150 N + 60 kg P₂O₅/ha at 60 DAS. Significantly higher cobs/plant (1.178), and grains/row (37.8) were produced by raising fertility level up to 120 kg N + 50 kg P₂O₅/ha, whereas grain weight/cob (80.41 g) and 1,000-grain weight (219.58 g) were significantly increased by applying 150 kg N + 60 kg P₂O₅/ha. Significantly higher grain yield (4.18 t/ha) and net returns (34.89 ×10³/ha) and benefit: cost ratio (1.88) were obtained under 120 kg N + 50 kg P₂O₅/ha. Application of 100% NP through fertilizers resulted in significantly higher weed dry matter at 30 and 60 days, yield attributes, grain yield (4.08 t/ha), net returns (36.19 ×10³/ha) and benefit: cost ratio (2.19). Application of pre-emergence atrazine + alachlor followed by hoeing and weeding gave the minimum weed density and dry-matter at 30 and 60 DAS. It also resulted in significantly higher yield attributes, yield (4.48 t/ha) and net returns (23.34 ×10³/ha).