Taxonomic evaluation of three Egyptian Solanum species based on morphology, DNA sequences, and chromosome analysis

Abstract

We investigated the intra-specific relationships between three Solanum species in Egypt: Solanum nigrum, Solanum villosum, and Solanum sinaicum, in addition to the inter-specific relationships among the populations of the three studied species. These species’ taxonomic difficulty is primarily due to its inconsistent infra-specific treatments in various floras. The morphological studies revealed distinguishing characteristics for the three investigated Solanum species mainly fruit and flower characteristics. The morphological differences allowed S. villosum to be divided into two subspecies: subsp. villosum, and subsp. miniatum. The genetic variation between the three Solanum species was clarified using AFLP technique. The ribosomal DNA ITS1-5.8S-ITS2 region of the three studied species was sequenced using the universal primers ITS4 and ITS5. The DNA sequences of Solanum species were counted. The karyotypes of the species under examination were established using the chromosome number and genome size acquired from mitotic chromosomal preparations.