Effect of different nitrification inhibitors doses and varying nitrogen levels on productivity and economics of hybrid maize (Zea mays)

A field experiment was conducted during the rainy season of 2013 at New Delhi, to study the yield and economics of ‘PMH 3’ maize hybrid (Zea mays L.) under different doses of nitrification inhibitors and varying levels of nitrogen. The experiment was laid out in a randomized block design with 14 combinations of 3 nitrification inhibitors (dicyandiamide, neem oil and meliacin) each with 2 different concentrations and 2 levels of nitrogen (135 and 180 kg/ha). Highest number of cobs/plant, grain rows/cob and grains/row were recorded with the application of MCU₃₅₀@N₁₈₀. The grain yield, stover yield and harvest index of maize as influenced by different doses of nitrification-inhibitors and varying levels of nitrogen were found significant and the highest grain and stover yield (7.25 and 7.93 t/ha) were recorded with the application of MCU₃₅₀@N₁₈₀. DCD_10%@ N₁₈₀ recorded the highest cost of cultivation ( 38, 813/ha), whereas highest net returns ( 68, 482/ha) and net returns/rupee invested (1.99) were recorded under MCU₃₅₀@N₁₈₀ followed by MCU₇₀₀@N₁₈₀.( 66, 832/ha, 1.93), while the minimum ( 23, 633/ha, 0.74) in the control.