Abstract

Drought stress poses a significant threat to okra (Abelmoschus esculentus L.), impacting its growth, yield, and overall productivity. To effectively screen and select genotypes at the seedling stage for drought tolerance, this study aimed to standardize polyethylene glycol (PEG) 6000 concentration for drought simulation. Four genotypes-Pusa Sawani, Bhindi Panchwati, MS-1031, and Sonam, were evaluated under six PEG 6000 treatments ranging from 0% (control) to 30% (severe stress). Analysis of variance revealed highly significant differences (P < 0.01) for genotypes, treatments, and their interactions, underscoring the effectiveness of PEG in simulating drought conditions. Increasing PEG concentration resulted in significant reductions in shoot length, root length, and both fresh and dry weight across all genotypes. Notably, two genotypes, namely, Bhindi Panchwati and MS-1031 failed to survive at higher PEG concentrations of 25% and 30%. Strong positive correlations were observed between traits, such as days to germination and days to true leaf emergence (r = 0.95, P < 0.001), which highlights the key developmental stages that were impacted by drought. Dendrogram analysis revealed that early seedling traits clustered separately from biomass traits, indicating different sensitivities to stress at various growth stages. This study provides valuable insights into optimizing PEG concentrations for simulating drought stress and standardizing screening procedures for drought tolerance in okra. This is the first report on genotype-specific PEG standardization in okra, integrating morphometric clustering analysis.

Key words: Keywords: - Okra, drought, polyethylene glycol, correlation, clustering