Systematic phenotypic approach to explore wild sesame germplasm for enhancing yield attributing traits in cultivated sesame

Abstract Crop wild relatives represent an essential reservoir of untapped genetic diversity for crop improvement. Despite sesame ( Sesamum indicum L.) being an important oilseed crop, its wild relatives remain underutilized for characterization and breeding efforts. To comprehensively assess their potential, a field evaluation was conducted during the kharif seasons of 2022 and 2023 on 53 accessions belonging to seven wild, three S. indicum accessions, and three cultivated species. Thirty-four agro-morphological traits (18 qualitative, 16 quantitative) were characterized under field conditions. Substantial variability was observed across key traits, including plant height, branching patterns, leaf morphology, corolla structure and pigmentation, capsule size and shape, seed characteristics, and yield-contributing attributes. Multivariate analyses revealed significant clustering patterns, and several traits, notably capsule width, capsule length, corolla length, seed area and test weight, exhibited high heritability. Importantly, certain wild accessions such as IC621506 and IC557250 (early maturity), IC409053, IC204658, IC208661 and IC208662 (greater capsule number), and IC208661, IC208662 and IC409053 (superior seed yield per plant) outperformed cultivated sesame species. These novel accessions constitute valuable genetic resources for broadening the cultivated gene pool and enhancing breeding strategies. This study provides the first comprehensive characterization of morphological diversity in wild sesame species, underscoring their potential utility in developing high-yielding, resilient varieties that can address future agricultural challenges.