Cross transferability of finger millet SSR markers to little millet (Panicum sumatrense Roth. Ex Roem & Schult.)

Abstract

Little millet is an important cereal known as a “nutra-grain' because of its numerous health benefits. Due to lack of genomic information, the present study analyzed the cross-transferability of finger millet SSR markers to little millet. SSR analysis using genomic DNA with 18 available markers in little millet revealed that 12 SSR markers had unique amplicons with the expected size, indicating 66.66 % cross-transferability. This indicates the conservation of the repetitive motifs AG, CTG, GTT, ACG, CGG, (GA)₂₆, (TC)21, (CA)₇N₁₂ (GA)₁₅, and (GA)₇AA (GA)₁₉ in both species. Genetic analysis with these transferable twelve SSR markers in 16 little millet genotypes revealed a total of 39 alleles with an average of 3.25 alleles per primer. The highest number of alleles (8) was found at GB-FM -53, while the lowest number of alleles (2) was found at GB-FM -67, GB-FM -87, GB-FM -98 and UGEP-101. Out of the total twelve amplified primers, four primers GB-FM -53, GB-FM -67, GB-FM -70 and UGEP-93 were found to be highly effective and best based on highest SSR primer index value, observed and effective number of alleles, Nei genetic diversity, Shannon information index and polymorphic information content. Finger millet SSR markers distinguished sixteen genotypes of little into two major clusters, where two genotypes, WV-151 and WV-152, were highly diverse. This study establishes the high cross-transferability of finger millet SSR markers to little millet facilitating genomic research and breeding efforts for genetically neglected little millet.