Pollen Morphology of Polygala L. (Polygalaceae) from Turkey and its Taxonomic Implications

Abstract

Pollen morphology of Polygala taxa from the family Polygalaceae in Turkey is presented in this study. Pollen features of 18 species along with one undescribed species in the section Polygala were examined with light and scanning electron microscopy, 11 of which were studied and defined for the first time. Cluster analysis and principal components analysis were conducted to determine informative palynological characters and to discover similarities among the studied taxa. Based on qualitative and quantitative variables in the phenogram, the studied taxa were divided into three major clusters. Multivariate analyses revealed that apocolpium characters, including a psilate apocolpium, the presence of apocolpial lumens with granules and small depressions with psilate or rugulate walls are the most distinct features for discriminating Polygala taxa. Intraspecific variations in some pollen characters, such as the exine pattern and aperture membrane features, are reported for several taxa. Pollen morphological data obtained in the present study are compared with those from previous studies for a number of species, and the results are evaluated. In addition, the aperture number and its probable significance in the Turkish Polygala are considered for some taxa, with emphasis on their known pollination strategies.