Detection of True Hybrids in Pearl Millet Cross Combinations by Employing SSR Molecular Markers

Abstract

Pearl millet (Pennisetum glaucum L. R. Br.), a crucial staple food and significant cereal crop, is gaining prominence due to its versatile applications as feed, food, and fodder. Heterosis of this crop has been extensively harnessed to increase productivity. Hybrid variants exhibit superior grain and stover yields compared to open-pollinated varieties.Top of Form The primary aim of this investigation was to evaluate and confirm authentic hybrids within three resultant F1 progenies. The assessment of parents and F1 hybrids was carried out during the Kharif 2021for the purpose of accurate discrimination and rapid verification of true hybrids by employing 20 SSR molecular markers. The experimental materials consisted of three distinct cytoplasmic male sterile (CMS) lines including ICMA 843-22, ICMA 04999, and ICMA 02333, used as female parents along with three fertility restorers, viz., ICMR 01004, ICMR 20233, and ICMR 20342, were utilized as male parents. The analysis of SSR profiles was based on distinctive banding patterns, resulting in unique profiles for the hybrids. The amplified fragment sizes ranged between 90 to 300 base pairs (bp), effectively enabling the differentiation of authentic hybrids. Within the specific crosses, the percentage of polymorphism was determined 75% for the cross ICMA 843-22 × ICMR 01004, 80% for the cross combination  ICMA 04999 × ICMR 20233, and 75% for the cross ICMA 02333 × ICMR 20342. The true hybrids were calculated using hybrid purity percentage formula using heterozygous banding patten among total plants evaluated. Among a total of 100 F1 plants, 85, 86, and 88 plants were accurately identified as true hybrids in the respective crosses i.e., ICMA 843-22 × ICMR 01004, ICMA 04999 × ICMR 20233, and ICMA 02333 × ICMR 20342. The identified markers hold significant potential for applications such as hybridity test, genetic purity assessments, diverse germplasm identification, and DNA fingerprinting endeavors in future.