Climate-Smart Agriculture (CSA) Practices for Sustainable Intensification in Major Agri-Food Systems of South Asia

Indo-Gangetic Plains (IGP) of South Asia is known for cereal (rice, wheat, and maize)-based major agri-food systems, which meet food requirement of 50% population in the region. Continuous cultivation of monotonous rice-wheat (RW) cropping system with traditional practices since the last six decades is showing threats to the systems’ sustainability. Future increase in food grain production might not be expected with business-as-usual practices. As per the Intergovernmental Panel on Climate Change (IPCC), the crop production in South Asia is expected to decrease by 30% particularly in cereal crops (rice, wheat, maize) by end of twenty-first century. South Asian farmers are mostly smallholders, their adaptive capacities are limited, and hence they are most vulnerable to climate change. Therefore, climate-smart agriculture (CSA) practices, comprised of three pillars (food security, adaptive capacity, and mitigation potential), are essential to design the new generation cereal systems to reduce farmers’ vulnerability to climate change. Sustainable intensification through the integration of short-duration legumes and by replacement of input exhaustive crops are required to maintain the systems’ sustainability in the region. Based on the on-station and off-station trials in South Asia, CSA-based modules had a potential to increase the system productivity and profitability by 5–15% and 20–25% in major cereal (rice, maize, and wheat) based agri-food systems vis-a-vis reduced the global warming potential by 15–35%. CSA-based production systems are found to be more resilient by improving soil quality (SOC—50–100%; NPK—30–50%). Smart application of input (through subsurface drip irrigation) saved irrigation water (~45%) and N (~20%) with slightly higher yields compared to conventional tillage (CT)-based systems. CSA layered with nutrient management tools like Nutrient Expert (NE) and GreenSeeker (GS) reduced the N input by 15–20%, increased crop yield by 4–8% and reduced the global warming potential by about ~3% in rice and ~15% in wheat. Results showed wider practical applicability and scalability, which may pave a way paradigm for scaling up cereal systems in South Asia in near future.