~ 1276 ~ International Journal of Chemical Studies 2020; 8(4): 1276-1282 P-ISSN: 2349–8528 E-ISSN: 2321–4902 www.chemijournal.com IJCS 2020; 8(4): 1276-1282 © 2020 IJCS Received: 20-05-2020 Accepted: 22-06-2020 Neeraj Kumar Department of Genetics and Plant Breeding, College of Agriculture, CCS Haryana Agricultural University, Hisar, Haryana, India Ram Avtar Department of Genetics and Plant Breeding, College of Agriculture, CCS Haryana Agricultural University, Hisar, Haryana, India Nisha Ahlawat Department of Genetics and Plant Breeding, College of Agriculture, CCS Haryana Agricultural University, Hisar, Haryana, India Rakesh Department of Genetics and Plant Breeding, College of Agriculture, CCS Haryana Agricultural University, Hisar, Haryana, India Corresponding Author: Neeraj Kumar Department of Genetics and Plant Breeding, College of Agriculture, CCS Haryana Agricultural University, Hisar, Haryana, India Molecular diversity analysis using Simple sequence repeats (SSRs) in ‘A’ and ‘R’ lines of Ogura CMS system in Indian mustard Neeraj Kumar, Ram Avtar, Nisha Ahlawat and Rakesh DOI: https://doi.org/10.22271/chemi.2020.v8.i4k.9778 Abstract Fifty-eight SSR primers were used for molecular diversity analysis among 45 ‘A’ and ‘R’ lines (5 A lines and 40 restorers) of Indian mustard. Out of 58 primers 33 primers were found to be polymorphic. A total of 95 alleles were detected across all 45 genotypes. The PCR amplified products ranged from 70 bp to 350 bp in size. The number of alleles per locus varied from 2 to 5 with an average of 2.89. The PIC value varied from 0.206 to 0.749 with an average of 0.519. The highest PIC value was obtained for BG 132 (0.749) followed by BG 114 (0.744). The UPGMA cluster analysis suggested demarcation of 45 genotypes into six distinct groups in dendrogram wherein three groups had single genotype (restorer line) each. Cluster VI consisted of all five Ogura CMS lines only. In the remaining clusters, restorer lines were distributed. Based on similarity coefficient, cross combinations viz., RH 0749-OA & IOR-17, RH 0749- OA & IOR-20 and RH 119-OA & OR-17 were identified as diverse and might be suitable for using parent in heterosis exploitation in Indian mustard. Keywords: Indian mustard, ‘A’ and ‘R’ lines, SSRs, molecular diversity Introduction Indian mustard [Brassica juncea (L.) Czern & Coss.], commonly known as raya, is one of the major oilseed crops cultivated in the Indian sub-continent. The predominant oilseed Brassica species plays a pivotal role in the vegetable oil economy. B. juncea (AABB; 2n=36) is a natural amphiploid arisen from hybridization between B. rapa (AA; 2n=20) and B. nigra (BB; 2n=16) followed by chromosome doubling which led to the evolution of it (U, 1935). The wild form of B. rapa and B. nigra are found in the Middle East hence, this region is the most probable place of origin of B. juncea (Prakash and Hinata, 1980) [11] . Indian mustard plays a crucial role in the Indian oilseed economy and shares about 23.5% area with 24.2% production of total oilseeds in the country. The oil content in Indian mustard varies from 38-46% (Tomar et al. 2015) [19] . Mustard oil is low in saturated fat and high in monounsaturated and polyunsaturated fat along with a significant amount of omega-3 fatty acids. The mustard oil-cake is a valuable protein source and recommended feed of cattle. The mustard seed contains some of the essential nutrients such as selenium, magnesium, dietary fibre, omega-3 fatty acids, vitamin B3, calcium, protein and zinc (Kaur et al., 2019) [6] . In India during rabi, 2018-19 Indian mustard was grown in an area of 6.94 million hectares with an output of 7.20 million tons. Yet, India meets 57% of the domestic edible oil requirements through imports and ranked 7 th largest importer of edible oils in the world. The further boom in human population and improved living standards has led to a rapid increase in the per capita oil consumption. Thus, there is an urgent need to increase the yield potential through genetic interventions to meet the present and future oil requirements. Heterosis breeding could be a potential alternative to substantially increase the productivity of Indian mustard (Ghosh et al., 2002) [4] . Attempts to exploit hybrid vigour have been stimulated by the availability of a large number of CMS sources. These are nap, polima, ogura, tournefortii, axyrrhina, siifolia, catholica, sinapis, trachystoma, moricandia and lyratus. Among these, Ogura (Ogu) CMS shows very stable and complete sterility suitable for hybrid development. Hybrid development depends upon the magnitude of heterosis. Heterosis in crosses involving diverse parents is generally higher than related parents. Hence, the selection of parents based