Integrated nitrogen management improves productivity and economic returns of wheat-maize cropping system

Abstract

Objectives: Continuous cultivation of rice and wheat crops in rice–wheat cropping system has resulted in numerous edaphic, social and environmental problems. Nonetheless, increasing water scarcity is also threatening the sustainability of rice–wheat cropping system. Therefore, farmers are compelled to cultivate alternative crops, like maize for water saving and higher economic returns. However, limited is known for integrated management of nitrogen (N) in wheat and maize crops. This study investigated the impact of integrated N management on productivity and profitability of wheat-maize cropping system. Methods: The study was conducted at Agriculture Research Farm of Bahauddin Zakariya University, Mulan, Pakistan. Wheat and maize crops were cultivated with recommended N dose using inorganic and organic sources, either alone or in combination with biofertilizer, while no N application was regarded as control. Data relating to root biomass yield and soil organic carbon (SOC) were collected. Results: Organic fertilizer alone and in combination with inorganic fertilizer and biofertilizer significantly improved root biomass and SOC. Improved SOC and crop root system resulted in better productivity of wheat-maize cropping system. Sole inorganic fertilizer application improved crop yield; however, had almost no effect on SOC. Integrated N management strategy (50% organic and inorganic fertilizer in combination with biofertilizer), improved crop yield (7168, 6405 kg/ha), net benefit (US$ 779, 961) and SOC (2.75%, 1.59%) for maize and wheat crops, respectively. Conclusion: Integrated N management strategy using different N sources seemed a viable and economically sound alternative of conventional N management, which would further strengthen the sustainability of wheat-maize cropping system.

Keywords

• Wheat-maize cropping system
• Nitrogen management
• Productivity
• Economic returns