Diversity analysis of Selected <em>Solanum</em> species in Sri Lanka using molecular and morphological descriptors

Abstract

The family Solanaceae is composed of a broad list of species, which includes both commercial and wild accessions with enormous medicinal importance. The published phylogenies on Sri Lankan wild and naturalized Solanum spp. confers that S. hispidum, and S. torvum are sister species. However, this has not been proved using multiple barcoding markers. Moreover, S. torvum, an underutilized crop is expected to contain multiple varieties. However, varietal descriptions using morphological and DNA markers have not been done so far. Therefore, our study was aimed at accurate identification of four Solanum spp. found in Sri Lanka (S. torvum 'Bindu' and landraces S. hispidum and S. pubescens) using chloroplast marker based DNA barcoding combined with a morphological description. We used 29 quantitative and 22 qualitative parameters, comprised of vegetative and reproductive traits along with eight DNA barcoding markers. We sequenced rbcL and trnL-F to check the DNA polymorphisms. According to the combined morphological analysis of reproductive and vegetative parameters, the four species clustered separately. There were no separation observed between S. torvum and S. hispidum. Solanum pubescens diverged out and cladded with old world nightshades in molecular analysis. These results are in line with published literature and validates that trnL-trnF could be used as a potential marker to carry out a combined DNA barcoding analysis with matK. However, trnL-trnF could not be used to discriminate between S. torvum and S. hispidum species.