Agronomic performance, nutritional quality and cooking traits of common bean genotypes grown under terminal drought conditions

ABSTRACT Drought stress significantly impacts the agronomic and nutritional properties of common bean (Phaseolus vulgaris L.), affecting agronomic traits, content of bioactive compounds and their antioxidant activity. This study evaluated the effect of two water regimes-no drought (ND) and terminal drought stress (DS)-on 20 bean genotypes and commercial cultivars over two growing seasons. Productive and quality traits were assessed, including grain yield (GY), number of grains per pod (NGP), hundred-grain weight (HGW), hydration capacity (HC), cooking time, crude protein content, total phenolic content, and DPPH-based antioxidant activity. Results showed a significant reduction (p < 0.001) in GY (-22.3%) and NGP (-61.3%) under DS, while HC increased for most genotypes (+1.9%). Some genotypes, such as 464, 483, and 478, maintained high GY (> 3600kg ha-1) despite reduced NGP. A positive correlation was observed between seed weight and protein content (r = 0.4) under ND and DS conditions. Under DS, most genotypes exhibited increased phenolic compounds and antioxidant capacity, highlighting their potential for stress resilience. The study highlights the intricate relationship between productivity, grain quality, and drought resistance in common beans. These findings provide valuable information that could contribute to improving the genotype selection process and development of common bean cultivars, highlighting the importance of selecting genotypes for both high yield and grain quality under water-limited conditions, while enhancing the sustainability and resilience to climate variability in this important crop.