Study of stem and leaf anatomy in the genus Thalictrum from Ranunculacae family in Iran

The genus Thalictrum L. is one of the large genera of Ranunculacea family. In this study 16 population from six species and two varieties (Th. mazandaranicum، Th. minus var. majus و Th. sultanabadense و Th. isopyroides ,Th. foetidum Th. tacabicu ) have studied anatomically. The specimens have collected from their natural habits and after hand sectioning and double staining have studied. The main anatomical characters of stem were : the shape of cross section of stem, number of cholenchyma cell layers, number of schleranchyma cell layers, number of internal phloem layer, presence and number of axial parenchyma, number of vascular bundle rings, and anatomical characters of leaf epidermis such as: number of subsidiary cells, shape of cell epidermis, stomata type, length of guard cells and epidermis tricumes were the most important characters for separating the Thalictrum species. Counspicaous differences in leaf epidermis are trustful solution for separating the species.
Finaly number of palliside parenchyma rows, presence of scleranchyma fibre around vascular bundles in central midribes, presence of cholenchyma cells and trichume types were the most important anatomical characters that could diagnosing the speciesa from each other.