Evaluation of Abiotic Stress Resilience in Traditional Aromatic Joha Rice Cultivars of Assam during Early Growth Stages

Abstract Abiotic stresses pose significant challenges to agriculture, particularly under changing global climatic conditions. This study evaluates the resilience of 19 traditional aromatic Joha rice cultivars of Assam, India to heat, cold, drought, submergence, and acidic stress during early growth stages. Morpho-physiological responses of the cultivars were analyzed under both control and stress conditions, and stress tolerance indices were calculated using the iPastic tool. A total stress response index (TSRI) was developed by summing the cumulative stress indices for each variety, enabling a comparative assessment of their tolerance levels. Based on TSRI values, a cluster heat map was generated, revealing ‘Bakul Joha’ as the most tolerant cultivar and ‘Keteki Joha’ as the most susceptible. These findings highlight the potential of morpho-physiological traits and TSRI as reliable markers for screening and selecting stress-resilient rice varieties. The results can contribute to future breeding programs aimed at developing Joha rice cultivars with enhanced adaptability to diverse abiotic stress conditions.