Assessment of chromosomal diversity and underlying relationships among Solanum melongena cultivars and its closest allied species in the subtribe Leptostemonum of Solanaceae based on EMA- fluorescent karyotypes and nuclear ITS sequence analysis
Considering the economic importance of eggplants in India and diversity of cultivars in West Bengal, there is a basic gap in systematic documentation of underlying relationships among widely cultivated brinjal eggplants (Solanum melongena), gboma eggplant (S. macrocarpon), scarlet eggplant (S. aethiopicum) along with other CWRs (S. insanum and S. incanum being the closest species and three distantly species S. viarum, S. virginianum, S. donianum) in Leptostemonum clade. The hypothesis behind the project is that brinjal eggplant clade has inter-specific chromosomal diversity between cultivated eggplant and wild forms and also has infraspecific diversity among the S. melongena cultivars that are highly variable in fruit types. In a previous study, intra- and infra-specific chromosomal differences have been found in line with morphotype differences in chilli pepper species (Capsicum annuum, C. chinense and C. frutescence) of Solanaceae. In order to test the current hypothesis, the key questions raised are like: i) do the diverse eggplant cultivars have significant variations in terms of ploidy/ genome size and karyotype? ii) how do the wild relatives of eggplant share chromosomal relationship with the cultivated forms? iii) Do the cytogenetic relationships among cultivated eggplants and wild species correlate with molecular phylogenetic data? The project will apply advanced cytogenetic techniques complemented with ITS sequencing analysis to find answers to these questions and test the current hypothesis. The result will provide a usable chromosomal catalogue of the divesre cultivated forms of eggplant in West Bengal versus the select wild species to complement future of eggplant breeding and genomics databases in India.