Phylogenetic Relationships Among Eggplant Species: Insights from ITS5 and trnL-F Molecular Markers

Karataş M. D., Boncukçu S. D.

Türk Tarım ve Doğa Bilimleri Dergisi, cilt.13, sa.4, ss.621-634, 2026 (Hakemli Dergi)

Özet

Approximately 2300 species have been identified within the Solanaceae family, with almost half belonging to the genus Solanum. Among these, eggplant (Solanum melongena L.) stands out as an economically important crop grown in tropical and subtropical regions. This study investigated the genetic relationships among 13 eggplant accessions representing 11 Solanum species using internal transcribed spacer (ITS) and cpDNA trnLF sequence data. This study also compared the performance of Neighbor Joining (NJ) and Maximum Likelihood (ML) methods in resolving the phylogenetic relationships among eggplant accessions. ITS5 sequence lengths ranged from 424 to 700 bp, whereas trnL-F sequence lengths ranged from 464 to 680 bp. Both markers differentiated the examined accessions, although the resulting tree topologies varied according to the marker and phylogenetic method. In the ITS5-based analyses, S. insanum, S. incanum, S. indicum, and S. aethiopicum (22) formed a closely related group, while S. anguivi was clearly differentiated from the other accessions. In the trnL-F-based analyses, S. insanum, S. incanum, and S. indicum were consistently grouped within the same cluster. The ML analyses produced high bootstrap support for several major clades, reaching 100% for ITS5 and 98% for trnL-F. However, bootstrap support varied among individual nodes depending on the marker and phylogenetic method. Overall, the ML method provided clearer phylogenetic separation of eggplant accessions than the NJ method based on both ITS5 and trnL-F data. In addition, ITS5 showed greater discriminatory power than trnL-F markers across all analyses. In conclusion, these findings provide useful insights into the genetic relationships among cultivated eggplant and its wild relatives and may support future germplasm conservation and breeding studies.