Molecular Characterization of Solanum Species Using EST-SSRs and Analysis of Their Zinc and Iron Contents

Aims: The objectives of study were to establish genetic diversity among the populations of three Solanum sp: Solanum torvum, Solanum aethiopicum and Solanum anguivi and identify species with the highest concentration of iron and zinc which can be recommended for improved maternal and child nutrition. It also aimed to identify polymorphic markers useful in Solanum species diversity studies or screening in Ghana.

Place and Duration of Study: CSIR-Crops Research Institute, Molecular Biology Lab, Kumasi. The study was carried between March 2011 and June, 2012.

Methodology: Investigations were carried out on 30 accessions of three Solanum species assembled from five geographical regions of Ghana. EST-SSR and AAS were employed for the estimation of genetic diversity and assessment of mineral concentrations respectively. Data generated were analysed using POPGENE version 1_32, Genstat software version 9 and Microsoft excel software (Windows 2007).

Results: All the markers showed allelic polymorphism in all the accessions studied. Overall genetic diversity was considerably high (I =1.0032, He = 0.4942, Nei’s He = 0.4859) and fixation index statistics (Fst) shows that 10% of the variation exists among the population. Clustering of the accessions did not exactly coincide to the populations of the different Solanum sp under study. Outcrossing rate (t = 0.8154) and Gene flow (Nm = 2.2071) of populations of the accessions were extremely high. Assessment of their mineral contents suggests that S. torvum and S. aethiopicum species are rich in Fe and Zn respectively.

Conclusion: EST-SSR markers and mineral analysis revealed genetic diversity among the different accessions. However the population studies suggest gradual homogeneity of these accessions due the high gene flow and outcrossing rate over time.