Abstract Seedling vigour is a key trait ensuring uniform crop establishment and stable yields, especially under direct-seeded/aerobic systems and abiotic stress conditions. This study aimed to evaluate 31 rice genotypes using an integrated approach combining morphological screening, physiological assessment and molecular analysis for seedling vigour. The experiment was conducted during the wet season of 2019 at Indian Council of Agricultural Research (ICAR) - Indian Institute of Rice Research (IIRR), Hyderabad, India, and the Department of Seed Science and Technology, College of Agriculture (CoA), Professor Jayashankar Telangana Agricultural University (PJTAU), Hyderabad, India and oxygen-sensing-based seedling vigour analysis was additionally performed at the University of Hohenheim, Germany. Significant genotypic variability was observed and seedling dry weight recorded the highest heritability (90.7%). High genetic advance as percent of mean (GAM) was noted for coleoptile length (66.1%). Seedling length exhibited a significant positive correlation with seedling vigour index (0.97***), shoot length (0.67***), root length (0.59***), and seedling dry weight (0.37*). Q2 scanner-based physiological profiling revealed that oxygen metabolism rate (OMR) showed significant positive correlation with seedling vigour index (0.98***) and seedling length (0.97**), with Dular recording the highest OMR. However, there were no significant correlations among the Q2 parameters. Based on morphological observations genotypes, Vandana, AUS 276, N22, Adday Sel and Bala were observed with high seedling vigour. Molecular screening indicated suggestive association between validated SSR markers and key seedling vigour traits, with genotypes such as AUS 276, Varalu, UPLRI5, RNR 15048, Teqing and Black Gora carried multiple reported QTLs. The SSR markers evaluated (RM15337 for coleoptile length, RM6326 for mesocotyl length, RM264 for root length, RM148 and RM85 for shoot length) provide indicative evidence for preliminary use in early-stage screening; however, further validation in structured mapping populations is required prior to marker-assisted selection (MAS). Future studies should validate these findings across diverse environments and leverage advanced genomics platforms such as high-density SNP arrays, GWAS and sequencing-based approaches to identify novel loci and refine candidate gene resolution. Integrating molecular markers, physiological traits like OMR, seed enhancement strategies and gene-editing technologies will support the development of high-vigour rice cultivars and improved early crop establishment.
Akshitha et al. (2026) studied this question.