Precision nutrient management and conservation agriculture practices for enhancing productivity, profitability and water-use efficiencies of maize-wheat -mungbean cropping system

Abstract

The maize-wheat-mungbean (MWMb) cropping system is being advocated as an alternative to the traditional rice-based cropping systems of north-western Indo-Gangetic Plains (IGP) to address the issues of energy and nutritional scarcity, residue burning, decline in biomass productivity and water tables. In semi-arid regions, the climate-change-induced variability in rainfall and temperature may have an impact on phenological responses of cereals and pulses which in turn would affect biomass production, economic yield and energy and water-use efficiency (WUE) of the crops. Henceforth, quantification of bioequivalent yields, energy requirement, economics and WUE of MWMb system is essentially required owing to have better understanding of this cropping system. Following a 5-year study was conducted under different tillage, crop establishment methods and balanced nutrient management practices showed that MWMb system productivity was recorded highest in zero till permanent (PB) plots and lowest in conventional tilled (CT) plots. PB and ZT plots registered 18.3% and 22.3% higher 5-year pooled MEY compared to CT-Control, respectively. Similar to tillage effects the nutrient management effect on MEY of MWMb rotation was also significant (P< 0.05) for all the 5-years where significantly higher yield was obtained in site specific nutrient management (SSNM) plots compared to other nutrient management plots. Tillage and nutrient management practices also had significant (P<0.05) effect on MWMb system pooled average water use efficiency and economics in 5-years of study. The year-wise cost of cultivation for different crops in MWMb system was almost similar in PB and ZT but was lower than CT plots. PB and ZT plots registered maximum MWMb system pooled average WUE (1.019 -1.131 US$ net returns/ha-mm), net returns (US$ 1819-1891/ha) and benefit cost ratio (1.68-1.73), respectively. Similar to tillage effects, the nutrient management also significantly (P<0.05) affected the MWMb system pooled average WUE and economics. Significant (P<0.05) increase in MWMb WUE and economics was recorded in SSNM and RDF for pooled average system WUE (30-35%), net returns (31-38%), and BC ratio (31- 32%), compared to FFP treatments, respectively. However, SSNM and RDF nutrient management treatments remained statistically at par with respect to system WUE, net returns and BC ratio. Thus, adoption of conservation tillage (ZT/PB) practices with improved balanced nutrient management (SSNM/RDF) could be a viable option for achieving higher biomass productivity, water and energy-use efficiency and profitability in MWMb system.