Pollen Morphology & Endocarp Studies of Rhamnus cathartica L., and Rhamnus pallasii Fisch. & C. A. Mey (Rhamnaceae) in North of Iran

Pollen morphology of Rhamnus pallasii and Rhamnus cathartica from the family of Rhamnaceae in North of Iran was examined under LM and SEM. Polar axis (P). Equatorial axis (E) and P/E were measured under LM. Exile ornamentation and endocarps of seeds were observed by scanning electron microscope. Based on pollen data, Rh.pallasii the shape is spheroidal and subtriangular in polar view; moreover, subprolate and tricolprate shapes were observed in equatorial view. Ornamentation of exine was obscure or indistinctly reticulate in Rh. pallasii subsp. iranica and Rh. X spathulifolia. Fruit of examined species was dropped with 2-3 seeds. All seeds were presented in ovate shape with light-brown color. Ornamentation of endocarp was foveolate and promaninted spotty. The biggest seed was presented in Rh. Pallasii and the smallest was observed in Rh. Pallasii subsp .Pallasii. The results of current research showed that ornamentation of exine is a valuable taxonomic character in the examined species; in addition, endocarp of seeds was to a great extent similar.