Four species of Salvia L., S. palaestina, S. spinosa, S. compressa, and S. multicaulis, sustained scrutiny by the internal transcribed spacer (ITS) fragments (ITS1, 5.8S rRNA gene, and ITS4) analysis with Ocimum basilicum to identify and explore their phylogenetic relationship based on many morphologically investigated properties. The analysis of the phylogenetic tree revealed that Salvia L. is a polyphyletic genera, indicating varying degrees of genetic relatedness among Salvia spp. and clearly distinct from Ocimum basilicum. This genetic differentiation is highly consistent with the obtained morphological data, which provide valuable insights into the evolutionary relationships between both genera and among Salvia spp. The observed genetic diversity highlights the reasons beyond morphological modification, including the number of biotic and abiotic environmental factors. Several characters, such as the calyx shape, corolla shape, and stamen features, revealed valuable taxonomic importance of the infrageneric and interspecific differentiating. The newly recorded ITS sequences attained the NCBI GenBank deposit to enrich the species database for more future investigations. The ITS markers represent the most preservative and useful taxonomic tools. Breeding approaches can employ genetic divergence and broad taxonomic phylogeny for Lamiaceae genera.

Keywords: Salvia, Ocimum, species, morphological traits, ITS, phylogenetic tree

Key findings: Morphological analysis of four Salvia spp. and Ocimum basilicum revealed many features of significant taxonomic importance. Molecular analysis based on nuclear ribosomal internal transcribed spacer regions (nrITS) results in the identification of studied taxa, with the new accessions deposited in the NCBI GenBank and construction of a phylogenetic tree.