REVISION ON TAXONOMY OF POLYGONUM SECTIONS IN IRAN BY PALYNOLOGICAL CHARACTERS

Abstract

Species belonging to different sections of the genus <em>Polygonum</em> L. were studied micro-morphologically. For this purpose, digital images were obtained from all species and lower taxa belonging to sections <em>Persicaria</em>, <em>Bistorta</em>, <em>Tiniaria</em> and <em>Pleuropterus</em>. Since section <em>Polygonum</em> is much diverse, pollens of three representative species <em>Polygonum luzuloides</em>, <em>P. olivascens</em> and<em> P. setosum</em> were photographed by Scanning Electron Microscopy (SEM). Based on SEM studies shape, size, ornamentation of exine and porate/colpate pollens are considered diagnostic for separating the sections from each other. An identification key to the section <em>Persicaria</em> is presented and section is to be promoted to genus level.