2026/06/22 by Erkan Şeker, Mehmet Çiçek, Okan Çon
Agricultural and Biological Sciences · #Plant Diversity and Evolution #Phytochemistry and Biological Activities #Essential Oils and Antimicrobial Activity
paper · doi:10.1080/01916122.2026.2693291
This study presents the pollen and seed micromorphology and their taxonomic significance of the Thymbra genus in Türkiye. Pollen and seed samples were analyzed using light and scanning electron microscopy, and quantitative measurements were recorded. Multivariate statistical analyses, including principal component analysis (PCA) and cluster analysis, were applied to assess variation and relationships among the taxa. Pollen grains were hexacolpate, mostly suboblate in equatorial view and hexagonal in polar view, with a bi-reticulate exine pattern. The polar axis (P) ranged from 25.31 to 32.45 μm, and the equatorial axis (E) ranged from 32.25 to 39.04 μm. Seed surface and size also varied among taxa, providing additional diagnostic traits. PCA and cluster analyses showed that pollen micromorphological traits effectively distinguish the five taxa, highlighting their taxonomic significance. T. capitata, T. spicata, and T. sintenisii formed distinct groups, primarily influenced by the polar axis (P), equatorial axes (E), amb (E1 and E2) and colpus measurements (Clg and Clt). Intine thickness, P/E ratio, lumina diameter, and reticula diameter were effective characters in differentiation, particularly enhancing discrimination at the subspecies level. The results obtained in this study are consistent with the most recent revision of the studied taxa. This study represents the first comprehensive pollen and seed morphology of Thymbra taxa in Türkiye, offering valuable data for species identification and classification within the genus.