Morphological and genetic diversity assessment of sesame (Sesamum indicum L.) accessions differing in origin

Abstract

Sesame is an important ancient oilseed crop of high medicinal value. In the present study, 37 characters including both quantitative and qualitative traits of sixty genotypes were characterized following IPGRI morphological descriptors for sesame. Multivariate analysis was computed to distinguish the varieties into different groups. Though thirty six microsatellite markers including genomic and Est-SSR markers were initially selected, but, finally, the accessions were genotyped by eight polymorphic primers. Altogether, 27 alleles were detected among the 60 genotypes, with an average of 3.37 alleles per locus. The number of alleles ranged from 2 to 6 alleles. From data of microsatellite markers, dissimilarity coefficients between varieties were computed following Jaccard's coefficient method. Principal co-ordinate analysis was used to represent the varieties in bi-directional space. Dendrogram was constructed using NJ method based on dissimilarity matrix. Cluster analysis based on morphological and molecular marker classified sesame genotypes into two major groups. Mantel test showed an insignificant correlation between phenotypic and molecular marker information. The genotypes belonging to the same geographical area did not always occupy the same cluster. The results confirmed that both genetic and phenotypic diversity in a combined way could efficiently evaluate the variation present in different sesame accessions in any breeding program.

Assessment of Genetic Diversity in Indigenous Sesame Genotypes

“…Each marker amplified 1 to 5 alleles with an average of 2.89 alleles per locus. The SSR markers in the present study showed a lower number of alleles than previous analysis of the diversity of sesame accessions conducted with SSR markers (Dixit et al, 2005;Gebremichaeland Parzies, 2011;Kumar and Sharma, 2011;Nweke et al, 2015;Pandey et al, 2015).…”

Relationship of Parental Genetic Distance with Heterosis and Specific Combining Ability in Sesame (Sesamum indicum L.) Based on Phenotypic and Molecular Marker Analysis

“…In an earlier study reported by Pandey et al (2015), a collection of 60 sesame genotypes including exotic collections, indigenous collections and landraces were classified based on morphological and marker analysis which served as a base population for selection of seven parents. Based on three clustering pattern and yield performance records, the seven parents namely, Gujarat Til-2 (Western India), TKG-22 (Central India), OSC-593 (South Eastern India), , , UMA (South Eastern India) and one indigenous collection, NIC-8316 (Eastern India) (Table 1) from five major sesame-growing states of India were selected for a 7 9 7 half-diallel mating design.…”

“…DNA amplification was done in 25 μL reaction mixture that consists of 0.2 μmol L −1 SSR primers, 0.2 mM of each dNTPs, 2 mmol L −1 MgCl 2 , 1X PCR buffer and 0.5 unit Taq polymerase, and 50 ng sample DNA. The procedures for SSR and Est-SSR were performed on a DNA thermocycler kit (Eppendorf AG 6321, Germany) as described by Pandey et al (2015). 3% agarose gel (Sigma USA) was used for separating the amplified PCR products.…”

Genetic variation via SSR polymorphic information content and ecological distribution of Nigerian sesame

“…Microsatellites or simple sequence repeat (SSR) is considered a good choice because of high abundance and reproducibility, easy scoring, low cost, extensive coverage, high polymorphic information content (PIC)and its co dominant nature (Wei et al,2014;Pandey et al, 2015;Dossa et al, 2017a).…”