Genetic Divergence in Foxtail Millet (Setaria italica L.) Germplasm Accessions for Quality and Yield Contributing Traits

Millets, particularly foxtail millet (Setaria italica L.), are gaining renewed attention for their nutritional, agronomic and ecological advantages. Despite its potential, genetic improvement of foxtail millet has been limited compared to major cereals. This study aims to evaluate the genetic divergence among 72 core germplasm accessions of foxtail millet and quantify carotenoid content in selected high-yielding lines to support future breedin g efforts. Although the genetic resources are large in this crop, it is kept unused and said to be underutilized crop. Thus, it is more important to expose the genetic parameters for the desirable traits in the germplasm accessions to improve its quality with yield. Hence, the evaluation of genetic resources had been taken for future research.

The present study aimed to assess the genetic diversity and carotenoid content among 72 foxtail millet accessions and two check varieties [CO (Te) 7 and ATL 1] sourced from the Ramiah Gene Bank. Field evaluations were conducted using a randomized complete block design (RCBD) at the Centre of Excellence in Millets, Tamil Nadu, during the 2023 Rabi season. Nine qualitative and eleven quantitative traits were recorded.

Cluster analysis based on Mahalanobis D² statistics grouped the accessions into six clusters, indicating significant genetic diversity. Cluster III exhibited superior performance for key agronomic traits, while Cluster IV had the lowest mean for days to maturity, suggesting potential for breeding early-maturing, high-yielding varieties. The traits contributing most to genetic divergence included plant height (20.79%), panicle length (15.50%) and single plant stover yield (14.75%). Additionally, carotenoid content analysis in 25 elite accessions revealed a range from 0.18 to 1.68 mg/100 g, with accessions TGP/ISE-26 and TGP/ISE-183/1 showing the highest levels. The findings highlight promising genotypes for genetic improvement programs focused on yield and nutritional enhancement, particularly for biofortification with carotenoids.