Semi-arid cropping and circular value chains for climate-resilient agriculture

Semi-arid agriculture faces increasing challenges from water scarcity, climate variability, and economic risk linked to monoculture systems. This review develops a framework linking drought-tolerant crop adaptation to downstream potential for grain sorghum, sesame, sunflower, and guar. Unlike prior reviews that treat agronomy and value chains separately, this work integrates crop composition, processing, and deployment constraints to evaluate circular, value-added systems. A structured narrative synthesis was conducted across agronomy, phytochemistry, extraction, and techno-economic studies, mapping crop-specific molecular profiles to functional properties. Literature was selected based on relevance to (i) drought adaptation and compositional variability, (ii) compound-specific functionality, and (iii) process scalability and value-chain integration. Across all four crops, deployment feasibility appears governed by system-level constraints, including logistics, processing scale, regulations, and market absorption. The framework identifies key knowledge gaps and barriers for scalable, climate-resilient, and economically viable systems in semi-arid regions.