Pollen morphology of six Achillea L. sect. Achillea (Asteraceae) species in Turkey

Authors : Hanife AKYALÇIN, Turan ARABACI, Bayram YILDIZ

Pages : 183-201

View : 13 | Download : 5

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The pollen morphology of 48 specimens of 6 species insert ignore into journalissuearticles values(9 taxa); of the genus Achillea L. sect. Achillea insert ignore into journalissuearticles values(Asteraceae);, A. nobilis L. subsp. neilreichii insert ignore into journalissuearticles values(A.Kern.); Formánek, A. nobilis subsp. densissima insert ignore into journalissuearticles values(O.Schwarz ex Bässler); Hub.-Mor., A. nobilis subsp. sipylea insert ignore into journalissuearticles values(O.Schwarz); Bässler, A. nobilis subsp. kurdica Hub.-Mor., A. filipendulina Lam., A. clypeolata Sm., A. coarctata Poir., A. biebersteinii Afan., and A. cappadocica Hausskn. & Bornm. distributed in Turkey were investigated using light insert ignore into journalissuearticles values(LM); and scanning electron microscopy insert ignore into journalissuearticles values(SEM);. The pollen grains were oblate-spheroidal, prolate-spheroidal, subprolate and generally tricolporate, though at times tetracolporate or even pentacolporate. The size of the grains varied, ranging from 17.6 to 57.5 µm on the polar axis mean and from 19.7 to 55.2 µm on the equatorial axis mean. Their outline is oval, compressed oval, or circular in the meridional optical section and trilobulate or sometimes tetralobullate in the polar optical section. The structure of the exine is double tectate and mean exine thickness varied from 3 to 8.5 µm. The pollen ornamentations are echinate in LM and echinate-microperforate and echinate-rugulate-microperforate in SEM. In conclusion, the species examined showed substantial variation in pollen characteristics, at both the interspecific and intraspecific levels.
Keywords : Key words Achillea, Compositae, LM, pollen morphology, SEM, taxonomy