Comprehensive Phenotyping of 1,807 Indian Barnyard Millet (Echinochloa frumentacea Link) Accessions from Indian National Genebank: Unlocking Diversity for Core Set Development

Badal Singh^*Sushil PandeyS NivedhithaNeelam ShekhawatMamta SinghBalram JatChithra Devi PandeyD P SemwalLalit AryaR K GautamG P Singh

• National Bureau of Plant Genetic Resources, Indian Council of Agricultural Research (ICAR), New Delhi, India

A comprehensive characterization of 1,807 barnyard millet (Echinochloa frumentacea Link.) accessions conserved in Indian National Genebank (INGB) was conducted to assess genetic variability and develop a representative core set. Thirteen qualitative and ten quantitative traits were evaluated, revealing significant diversity. Predominant traits included pyramidal inflorescence shape (89%), green inflorescence color (57%) and intermediate inflorescence compactness (46%). Plant height ranged from 72.36 to 213.96 cm, inflorescence length varied from 6.73 to 35.65 cm and 1000-seed weight varied from 1.01 to 5.55 g, demonstrating the wide range of quantitative characteristics. High heritability values (82.08-94.42%) and substantial genetic advances in these traits highlight their importance for agronomic improvement. Five core sets were created using Core Hunter 3, utilizing optimization approaches to enhance representativeness and diversity in order to capture the diversity of the full collection. Among these, core set-3, comprising 271 accessions, achieved the best balance of genetic diversity, trait representativeness and low redundancy. Important indicators were a variable rate of coefficient of variance (VR) of 110.41%, a coincidence rate (CR) of 85.97% and a mean difference percentage (MD) of 30%, all of which were above the parameters for good core sets. Shannon-Weaver diversity indices and evenness values confirmed superior diversity representation of the core set.The representativeness of the core set was confirmed by a comparison of the core set with the entire collection, which showed non-significant differences in means, variances, and frequency distributions for the majority of traits. Correlation analysis and principal component analysis (PCA) confirmed the conservation of trait associations and genetic structures between the core set and the whole collection. PCA revealed that the first five principal components explained 74.9% of the total variance in the core set, closely aligning with the entire collection (70.8%). This study highlights the utility of the INGB barnyard millet core set as a valuable genetic resource for breeding programs. The core set provides opportunity for the effective use and preservation of barnyard millet genetic resources by improving access to genetically varied and agronomically significant germplasm.