Molecular Genetic Diversity of Major Indian Rice Cultivars over Decadal Periods

Abstract

Genetic diversity in representative sets of high yielding varieties of rice released in India between 1970 and 2010 was studied at molecular level employing hypervariable microsatellite markers. Of 64 rice SSR primer pairs studied, 52 showed polymorphism, when screened in 100 rice genotypes. A total of 184 alleles was identified averaging 3.63 alleles per locus. Cluster analysis clearly grouped the 100 genotypes into their respective decadal periods i.e., 1970s, 1980s, 1990s and 2000s. The trend of diversity over the decadal periods estimated based on the number of alleles (Na), allelic richness (Rs), Nei’s genetic diversity index (He), observed heterozygosity (Ho) and polymorphism information content (PIC) revealed increase of diversity over the periods in year of releasewise and longevitywise classification of rice varieties. Analysis of molecular variance (AMOVA) suggested more variation in within the decadal periods than among the decades. Pairwise comparison of population differentiation (Fst) among decadal periods showed significant difference between all the pairs except a few. Analysis of trends of appearing and disappearing alleles over decadal periods showed an increase in the appearance of alleles and decrease in disappearance in both the categories of varieties. It was obvious from the present findings, that genetic diversity was progressively on the rise in the varieties released during the decadal periods, between 1970s and 2000s.

Physio-biochemical and molecular characterization for drought tolerance in rice genotypes at early seedling stage

“…These results agree with Babu et al (2014) and Choudhary et al (2013). These differences could be attributed to differences in genotypes as well as SSR primers.…”

Genetic diversity and population structure of Bambara groundnut (Vigna subterranea (L.) Verdc.): synopsis of the past two decades of analysis and implications for crop improvement programmes

“…Genetic diversity, population structure analysis and its implication for crop improvement programmes Molecular genetic diversity analyses have been used to aid breeding decisions and germplasm conservation agenda in crop species (Choudhary et al 2013;Huynh et al 2013). Specifically for Bambara groundnut, various molecular analyses of diversity have been reported to either argument or validate the various reports based on phenotypic descriptors (Table 6; Pasquet et al 1999;Massawe et al 2003aMassawe et al , 2002Olukolu et al 2012;Aliyu and Massawe 2013;Mayes et al 2013;Molosiwa et al 2015).…”

“…The use of molecular markers to assess genetic diversity in landraces, breeding lines, varieties, wild relatives and mutant populations to aid breeding decisions in major crops such as rice (Oryza sativa L.) (Zhang et al 2011;Choudhary et al 2013), maize (Zea mays L.) (Lu et al 2011;Wen et al 2012), soya bean (Glycine max (L.) Merr.) (He et al 2012) and cowpea (Vigna unguiculata (L.) Walp.)…”

Review of methods for the detection and quantification of adulteration of rice: Basmati as a case study

“…As of now, more than 50,000 microsatellite markers are on hand in the rice. Microsatellite DNA markers have been extensively used in mapping and tagging genes, study of diversity, phylogeny and population genetics, disease diagnosis, and forensic Nakamura and Ohtsubo (2010) investigations (Coburn et al 2002;Srividhya et al 2010;Yadav et al 2013;Choudhury et al 2013;Vemireddy et al 2007). In addition, microsatellite markers have the potential to be used for unequivocal detection and quantification of adulteration in Basmati rice (Bligh 2000;Archak et al 2007;Vemireddy et al 2007).…”