Morphological and Palynological Studies in Some Achillea L. Species (Asteraceae) of Iran

Morphological and palynological studies were performed in 34 populations of 12 achillea species belonging tothree sections of santolinoidea, millefolium and fitipendnlinae growing in iran. morphological studies wereperformed on 34 populations of 12 species. in total 33 morphological characters including 13 quantitative and 20qualitative were scored. anoya test showed significant difference for most of quantitative characters among thespecies and populations studied. upgma clustering of the populations and species studied based on merelyquantitative morphological characters and also based on both quantitative and qualitative characters separatedpopulations of each species from the others indicating the use of these characters in species delimitation. however noresolved relationship could be obtained and the species from 3 sections stated in flora iranica are intermingled. thesize of the pollen grains ranged from 22.4-30.0 urn, with similar pie ratio, trizonocolporate, radially symmetrical,isopolar, spheroidal. the spines are pointed and are dome shaped broad based. the number of spine rows betweencolpi varies from 3 to 5 among the species. this feature can be determined easily in the polar view by lightmicroscope. the exine thickness varies from 2.4 (mu)m to 4.5 (mu)m among the species and pollen sculpturing is echinatein all. clustering and ordination of species based on palynological characters also showed mixing of species from 3 sections mentioned in flora iranica.