Yield components and nutrient accumulation in maize (Zea mays) under variable growing environments and chlorophyll meter-guided nitrogen fertilization

A field experiment was conducted during 2014–15 on sandy loam soil at ICAR-Indian Agricultural Research Institute, New Delhi, to study the effect of different growing environments and chlorophyll meter-based nitrogen (N)management practices on yield components, yield and nutrient uptake in maize (Zeamays L.) cultivars. Maize hybrid ‘PEEHM 5’ exhibited significantly larger yield attributes and higher grain yield than ‘Pusa Composite 3’ (‘PC 3’), and earlier planting dates, 9 July and 24 July, depicted significant edge over later planting on 7 August. Chlorophyll meter-based N application up to silking (CMB), i.e. 30 kg/ha N basal + 30 kg/ha N top-dressed when soilplant analysis development meter (SPAD) value falls to ≤ 37.5, increased the magnitude of all yield attributes and yield compared to soil-test-crop response based (STCRB)-N application. Grain N, P and K uptakes were 13.3, 30.7 and 11.8%, respectively, higher in ‘PEEHM 5’ than in ‘PC 3’. Similarly, CMB N application resulted in 17.2, 18.7 and 11.2% higher N, P and K uptake in grain and 9.3% greater grain yield compared to STCRB N. Overall, variety ‘PEEHM 5’ planted on 9 July and fertilized with N based on chlorophyll meter readings was a better option than the others with respect to yield attributes, yield and nutrient uptake in the north Indian plains.