Genetic variability of sorghum landraces from lower Eastern Kenya based on simple sequence repeats (SSRs) markers

Abstract

The aim of this study was to estimate the genetic variability of sorghum landraces grown in lower eastern Kenya based on simple sequence repeats (SSRs) markers. A total of 44 landraces obtained from the farmers and four improved varieties were analyzed using 20 SSR markers. All markers were polymorphic with polymorphism information content (PIC) value ranging from 0.04 to 0.81 with a mean of 0.49. Heterozygosity ranged from 0.00 to 0.04 suggesting that each detected a single genetic locus and that each of the sorghum accession used was stable. The alleles ranged between 2 and 10 and an average of 5.05 alleles per primer pair. The gene diversity ranged from 0.04 to 0.83 with a mean value of 0.53. All possible allele combinations ranged from 2 to 10, while major allele frequency ranged from 0.32 to 0.98. Genetic distances varied from 0.15 to 0.90 with two genotypes Karuge 1 and Karuge 2 obtained from Kiritiri in Mbeere having the minimum (0.15) and indication of very close relatedness. The diversity of the landraces was structured more on geographical locations and on seed colorations than agroecological conditions. Such intraregional genetic proximity in sorghum landraces would arise through seed exchanges among farmers. Analysis of molecular variation indicated higher variation within populations than among the groups. The genetic diversity can be exploited in hybridization programs to improve sorghum varieties grown by farmers in semi arid areas.

Genetic diversity of sorghum (<i>Sorghum bicolor </i>(L) Moench) accessions from thirteen regions of Burkina Faso

“…These markers do not vary much. Similar data were obtained by Barro-Kondombo et al (2010), Mbeyagala et al (2012) and Catherine et al (2016). The hypothetical K value obtained showed the three clusters in which the lines were embedded.…”

Genetic diversity analysis of sorghum [Sorghum bicolor (L.) Moench] races in Ethiopia using simple sequence repeats (SSR) markers

“…Similar findings by Cuevas and Prom ( 2013), and to a certain extent Agrama and Tuinstra (2003) also reported average PIC values 0.78 and 0.622, respectively. However, the observed PIC value is higher than that of Geleta et al (2006), Antoine et al (2015) and Catherine et al (2016) who reported 0.46, 0.33 and 0.49, respectively. This may be the result of low numbers of accessions considered in their studies and sample collections represented are from specific areas of agroecologies.…”

“…Qualitative and quantitative studies, in addition to RAPD, AFLP and SSR markers utilized by different scholars also revealed the same amounts of variations among their collections (Ayana and Bekele, 1998;Geleta et al, 2006;Cuevas and Prom, 2013). SSR marker studies from Eritrean, Eastern Kenya, Benin and Zambia collections also showed presence of wide genetic diversity of sorghum bicolor in Africa mainly in Eastern regions (Tesfamichael et al, 2014;Catherine et al, 2016;Antoine et al, 2015;Ng'uni et al, 2011). The existence of imbalanced sorghum races in the sample collections of the different studies from Ethiopia might contribute to the overall observed genetic variation (Cuevas and Prom, 2013).…”