Evaluation of yield based stress indices of barley landraces under drought condition

Barley ( Hordeum vulgare L.) is a historically marginalized crop that holds significant promise as a climate-resilient cereal due to its adaptability to marginal environments. This study assessed drought resilience in 14 barley landraces under controlled drought stress conditions using factorial completely randomized design with three replications. Drought was imposed at three critical growth stages-crown root initiations, tillering, and grain filling using the same plants sequentially, allowing assessment of genotype response to cumulative water deficit across crop development and agro-morphological and physiological traits were evaluated. Eight landraces completed maturity assessment, revealing substantial genotypic variation in drought response. Chlorophyll retention, measured through SPAD values, and earlier maturity were associated with higher yield or yield stability, suggesting that chlorophyll retention and drought-escape phenology may be useful traits for selecting drought-resilient barley landraces. AFU202501 exhibited outstanding yield and stability across environments, reflected by high Stress Tolerance Index (STI = 1.782), while Saptari Local demonstrated drought avoidance through early maturity and minimal yield reduction (SSI = 0.125). In contrast, Muktinath and NGRC 6010 were highly susceptible, suffering yield losses of up to 87%. These findings identify the complementary strategies of yield stability and drought escape in landraces, underscoring their values as genetic resources for breeding climate-resilient barley varieties. Incorporating such traditional germplasm into modern breeding programs offers a strategic pathway to strengthen food security in drought-prone regions.