Millet-based cropping systems as climate-resilient alternatives in dryland agriculture

Abstract:

Background: Dryland agriculture, which encompasses over 40% of the world's land area, is increasingly threatened by erratic rainfall, prolonged drought spells, and progressive soil degradation attributable to climate change. Millets-including pearl millet (Pennisetum glaucum), finger millet (Eleusine coracana), sorghum (Sorghum bicolor), foxtail millet (Setaria italica), and small millets-are ancient grain crops endowed with exceptional drought tolerance, thermal resilience, and minimal input requirements.

Methods: This review synthesizes evidence from over 180 peer-reviewed studies, experimental field trials, national crop surveys, IPCC reports, and FAO databases published between 1990 and 2024 to evaluate the agro-ecological, physiological, socio-economic, and climate adaptation dimensions of millet-based cropping systems in dryland contexts globally, with emphasis on South Asia and sub-Saharan Africa.

Results: Millets demonstrate superior water-use efficiency (2-5 g DM kg⁻¹ H₂O), thermotolerance up to 42°C, and robust performance on marginal soils with low nutrient inputs. Millet-based intercropping ad relay systems increase land equivalent ratios (LER 1.2-1.7), enhance system-level productivity, and diversify smallholder income. Carbon sequestration potential, nutritional superiority over cereals, and integration with livestock systems further amplify their climate-smart value proposition.

Conclusion: Millet-based cropping systems represent scientifically validated, climate-resilient alternatives for sustainable dryland agriculture. Policy-level mainstreaming, seed system reforms, market linkages, and value-chain development are critical to scaling adoption and ensuring food and nutritional security under future climate scenarios.