Nutrient Uptake of Fodder Cowpea Varieties as Influenced by Soil Moisture Stress Levels

A field experiment was conducted in the upland area of the Instructional Farm of College of Agriculture, Vellayani, Trivandrum during the summer season of 2012. The objectives of the study was to identify the nutrient uptake of fodder cowpea varieties. The investigation was conducted as two separate experiments, one in open and another in shaded situation (25–35 per cent shade). The design was laid out in split plot with four replications. The main plot factor included four soil moisture stress levels, M₁: presowing irrigation + life saving irrigation; M₂: presowing irrigation + irrigation at IW/CPE ratio 0.4; M₃: presowing irrigation + irrigation at IW/CPE ratio 0.6; M₄: presowing irrigation + irrigation at IW/CPE ratio 0.8. The sub plot factor included five fodder cowpea varieties, V₁-UPC-618, V₂-UPC-622, V₃-Bundel Lobia-1, V₄-COFC-8 and V₅-CO-5. Presowing irrigation was given to all the plots uniformly upto 10 days after sowing for germination and establishment. Thereafter irrigation was given as per the treatments based on the evaporation data and depth of irrigation. N uptake, P₂O₅ uptake, K₂O uptake, Ca uptake and Mg uptake increased significantly with increase in irrigation levels. Among the varieties, COFC-8 recorded significantly higher nutrient uptake in open and shade.