Effect of cultivars and levels of nitrogen, phosphorus and potassium on growth, yield and nutrient uptake of maize (Zea mays) hybrids

A field study was conducted during the winter season of 2013-14 and 2014-15 at farmer’s field, Gayeshpur, Nadia, West Bengal, to evaluate the performance of maize (Zea mays L.) as influenced by cultivars and levels of NPK. The experimental soil was clay in texture and neutral in reaction, having low available N, high available P and medium available K. The experiment was laid out in a strip-plot design with 3 maize hybrids (‘P 3522’, ‘P 3396’ and ‘Rajkumar’) in vertical strip and 9 NPK levels [50% recommended dose of fertilizer (RDF), 75% RDF, RDF (200 kg N, 60 kg P and 60 kg K/ha), 125% RDF, 150% RDF, 100% PK, 100% NK, 100% NP and control (zero-NPK)] in horizontal strip, replicated thrice. Maize hybrid ‘P 3396’ recorded better cob characteristics (cob length, cob girth and cob weight) and test weight, while other yield attributes (number of cobs/plant, number of grain rows and grains/cob) were higher in ‘P 3522’. Across cultivars, 125% RDF application resulted in significant increase in yield attributes over the control. The cultivar ‘P 3396’ recorded second best yield (grain and stover) after ‘P 3522’. Application of 125% RDF resulted in the maximum grain and stover yield with 124.5 and 91.2% increase over the control respectively. Total P and K uptake increased up to 125% RDF; however, total N uptake increased till 150% RDF application. Grain yield reduction, in comparison with RDF plots, was estimated to be 43.90% due to N omission, 16.76% due to P omission, and 26.94% due to K omission. Net returns and benefit: cost ratio continued to increase till 125% NPK, and decreased further with addition of NPK (150%).