Impact of conventional and nano fertilizers on rainfed maize yield, profitability and soil nitrogen
K.A. Gopinath, V. Visha Kumari, Vinod Kumar Singh, Arun K. Shanker, K. Sammi Reddy, S. Kundu, B. Bhargavi, B. V. Rajkumar, N. Lavanya, Pebbeti Chandana, B. Sunitha, M. R. Krupashankar, Tarunendu Singh
Abstract
Nitrogen (N) is a vital macronutrient for maize productivity, but significant losses under rainfed conditions limit its availability and yield potential. There is a need for energy-efficient and eco-friendly fertilizers along with improved agronomic practices to enhance nutrient use efficiency, crop productivity, and profitability. An experiment was conducted under semi-arid conditions in India in a single location to evaluate the economic and environmental performance of conventional fertilizers at varying nitrogen levels [0, 50, 75, and 100% recommended rate of nitrogen (RDN)] with and without nano-urea in rainfed maize. Application of 100% recommended NPK through conventional fertilizers along with nano-urea spray (N 100 PK + nano-urea) recorded significantly higher yield (3,026 kg ha -1 ) and economic returns (US $ 477 ha -1 ). Notably, the N 75 PK + nano-urea registered comparable yield over N 100 PK + nano-urea and N 100 PK, demonstrating that two foliar sprays of nano-urea could reduce nitrogen input by 25% without yield loss. Additionally, this approach reduced greenhouse gas (GHG) emissions by 25% and energy consumption by 14.9%, highlighting its potential for sustainable maize production. Though the results are encouraging it should be tested across crops and regions.