Identification of polymorphic SSR markers in elite genotypes of pearl millet and diversity analysis

Pearl millet is a climate-resilient crop of marginal agro-ecologies and semi-arid tropics of Asia and Africa. With substantial nutritional qualities crop requires low inputs and is capable of giving economic returns. Development of high-yielding hybrids is an important breeding objective for pearl millet worldwide. The knowledge of genetic diversity is a prerequisite for developing superior hybrids. In the current study, attempts were made to evaluate the diversity of 17 important Indian pearl millet inbred genotypes and one popular hybrid 9444 using fluorescent labeled SSR markers. A total of 342 polymorphic alleles with an average of 4.62 alleles per primer were produced from 74 SSR markers. Polymorphic information content (PIC) ranged from 0.10 to 0.89 with an average of 0.55. A very low level of heterozygosity was detected in genotypes. The average genetic dissimilarity detected between pairs of inbred lines was 0.66. Genetic dissimilarity estimates calculated among the inbred lines varied from 0.108 (AIMP-03 and AIMP-08) to a maximum of 0.851(AIMP-03/AIMP-08 and 81B). The results indicated that sufficient genetic variability is available in studied genotypes which can be exploited through heterosis breeding to develop hybrids. The study also presents a suit of SSR markers that could be effectively used for genetic diversity analysis in pearl millet.