Response of maize (Zea mays) hybrids to varying spacing and fertility levels grown during spring season

A field experiment was conducted during the spring season of 2013 at Chatha, Jammu, to study the response of maize (Zea mays L.) hybrids to varying spacing and fertility levels. The row spacing of 60 cm resulted in significantly higher grain yield, stover yield, heat-use efficiency (HUE), heliothermal-use efficiency (HTUE) and total NPK uptake by spring maize with higher net returns and benefit: cost ratio than row spacing of 70 cm._. Among the hybrids, ‘PMH 1’ exhibited significantly higher total NPK uptake of spring maize with concomitant significant increase of grain, stover yield and harvest index than ‘JH 3459’. However, the HUE and HTUE were significantly higher in ‘JH 3459’ than ‘PMH 1’. Hybrid ‘PMH 1’ also recorded higher net returns and benefit: cost ratio than ‘JH 3459’. Amongst the fertility levels, the application of N₁₄₀P_30.5K_29.2 kg/ha resulted in the highest grain and stover yields, nutrient uptake and soil-nutrient build up, which was statistically at par with N₁₂₀P_26.20K₂₅ kg/ha and significantly higher than N₈₀P_17.5K_16.7 kg/ha and N₁₀₀P_21.8K_20.8 kg/ha. The highest benefit: cost ratio was recorded with the application of N₁₂₀P_26.2K₂₅ kg/ha followed by N₁₄₀P_30.6K_29.2 kg/ha.