Genetic differentiation and geographical Relationship of Asian barley landraces using SSRs

Abstract

Genetic diversity in 403 morphologically distinct landraces of barley (Hordeum vulgare L. subsp. vulgare) originating from seven geographical zones of Asia was studied using simple sequence repeat (SSR) markers from regions of medium to high recombination in the barley genome. The seven polymorphic SSR markers representing each of the chromosomes chosen for the study revealed a high level of allelic diversity among the landraces. Genetic richness was highest in those from India, followed by Pakistan while it was lowest for Uzbekistan and Turkmenistan. Out of the 50 alleles detected, 15 were unique to a geographic region. Genetic diversity was highest for landraces from Pakistan (0.70 ± 0.06) and lowest for those from Uzbekistan (0.18 ± 0.17). Likewise, polymorphic information content (PIC) was highest for Pakistan (0.67 ± 0.06) and lowest for Uzbekistan (0.15 ± 0.17). Diversity among groups was 40% compared to 60% within groups. Principal component analysis clustered the barley landraces into three groups to predict their domestication patterns. In total 51.58% of the variation was explained by the first two principal components of the barley germplasm. Pakistan landraces were clustered separately from those of India, Iran, Nepal and Iraq, whereas those from Turkmenistan and Uzbekistan were clustered together into a separate group.

Comparison of allelic diversity between native gene resource plantings and selections in open-pollinated progeny test of Pinus radiata D. Don.

“…This loss is a reflection of the fact that almost 50 % of diversity is distributed among populations for inbred species (LOVELESS and HAMRICK, 1984). For example, NAEEM et al (2011) reported genetic diversity among populations to be 40% compared to 60 % within populations of Asian barley. However, maize provides an example of a domesticated form which maintained a high level of genetic diversity, although it is highly differentiated from its wild ancestor (LEFEVRE, 2004).…”

Analysis of genetic diversity and population structure of some Ethiopian barley (Hordeum vulgare L.) accessions using SSR markers

“…[13,42] reported average PIC values of 0.78 and 0.73 from ICARDA and Ethiopia, respectively. In contrast, lower PIC values of 0.58, 0.54 and 0.46 were reported by [57][58][59], respectively. In general, a PIC value greater than 0.5 is useful in genetic studies since it can distinguish a marker's polymorphism [60].…”

Genetic Structure and Geographical Relationship of Selected Colocasia esculenta [L. Schott] Germplasm Using SSRs

“…Allelic diversity is vital for delineating the potential of germplasm for further conservation studies and crop improvement. Previous reports have used SSRs in determining the number of alleles and alleles per locus in various food crops [18,19,10]. In general, as the number of cultivars in any given population increased so did the diversity and the number of alleles/locus.…”