Integrating molecular and phenotypic traits to evaluate drought stress responses in chickpea (Cicer arietinum) genotypes

Chickpea (Cicer arietinum) is a nutritionally valuable legume crops; however, its productivity is significantly constrained by drought stress. This study aimed to evaluate morpho-physiological traits and molecular response of chickpea genotypes under well-watered (control) and drought conditions to identify drought-tolerant lines. Plants of 83 chickpea genotypes (55–60 days old) were subjected to drought by withholding irrigation until soil moisture dropped 20–40%. Key physiological and agronomic traits such as relative water content (RWC), membrane stability index (MSI), chlorophyll content, yield parameters, drought tolerance efficiency (DTE), and drought susceptibility index (DSI) were measured. Data analysis was performed using R software for pairwise distance, correlation, Principal Component Aanalysis (PCA), and heat mapping. PCA explained 53.8% of the total variability, effectively separating genotypes based on stress response. Additionally, simple sequence repeat (SSR) markers were used to evaluate genetic variability. Genotypes SAGL19008 and SAGL162380 showed higher RWC, MSI, and chlorophyll content under drought, while genotype ICC4958 exhibited the highest DTE (101.19%) and the lowest DSI (60.54%), indicating strong drought tolerance. The identified genotypes hold potential for incorporation into breeding programs aimed at improving drought resilience in chickpea, thereby contributing to food security and sustainable agriculture.