Anatomical and palynological studies on Turkish Primula taxa (Primulaceae) and their taxonomic and phylogenetic significance

Abstract

Anatomical (scape, pedicel, leaf lamina, and leaf midrib) and pollen morphological features of 11 taxa belonging to the genus Primula subgen. Primula (P. vulgaris subsp. vulgaris, P. vulgaris subsp. rubra, and P. megaseifolia, P. meyeri, P. elatior subsp. pallasii, P. pseudoelatior, P. veris subsp. columnae, P. veris subsp. macrocalyx) and subgen. Aleurita (P. longipes, P. algida, and P. auriculata) were examined using light and scanning electron microscopy to shed light on the existing taxonomic and phylogenetic relationships. The anatomical and palynological features of the majority of the taxa studied were revealed for the first time in this study. In anatomical studies, the very large intercellular space under the epidermis, the number of sclerenchyma layers in the scape, and the midrib shape in the leaf lamina were found to be of taxonomic importance at the subgenus level. In palynological studies, pollen grain size, pollen surface ornamentation patterns, and pollen aperture types could be used as important characters to distinguish species, sections, and subgenera. Significant differences were found between subgenera and between the pollen grains of pin and thrum flowers of the same taxon. Mostly, the subgen. Aleurita taxa had significantly smaller pollen grains than the subgen. Primula taxa, and pollen grains from flowers with pin morphology were smaller than those from flowers with thrum morphology. Our studies showed that both anatomical and palynological features have not only taxonomic but also phylogenetic importance.