Pollen morphology of eight endemicInulaL. (Asteraceae) species in Turkey

The pollen morphology of eight endemic species of the genusInulaL. (Asteraceae) -I. heleniumsubsp.orgyalis(Boiss.) Grierson,I. heleniumsubsp.vanensisGrierson,I. macrocephalaBoiss. & Kotschy ex Boiss.,I. discoideaBoiss.,I. saranaBoiss.,I. fragilisBoiss. & Hausskn.,I. anatolicaBoiss. andI. sechmeniiHartvig & Strid - distributed in Turkey was studied with light microscopy and scanning electron microscopy. We found that the pollen of theseInulataxa are prolate-spheroidal in shape (except inInula discoidea), with the polar axis ranging from 19.18 to 33.14 mu m and the equatorial diameter ranging from 18.54 to 32.92 mu m. The pollen grains are tricolporate and their ornamentation is echinate. The exine thickness ranges from 0.87 to 2.07 mu m. As this study demonstrates, results of Principal Component Analysis are revealed that some of the pollen characters, such as spine length and width, are significant morphological characters for taxonomic discrimination of the eight endemicInulataxa. According to cluster analysis, two main groups of examined taxa are constituted.

Automated summary

The pollen morphology of eight endemic species of the genus Inula in Turkey was studied, revealing prolate-spheroidal pollen grains with tricolporate apertures and echinate ornamentation. Principal Component Analysis showed that spine length and width were significant morphological characters for taxonomic discrimination of these Inula species. Cluster analysis revealed two main groups among the examined taxa.