POLLEN MORPHOLOGY AND RAPD ANALYSIS OF SOME CLOSELY RELATED TAXA OF POLYGONUM.

Abstract: Study on pollen morphology of 3 varieties of P. chinense was undertaken by acetolysis method and DNA polymorphism in 4 species and 2 varieties of Polygonum collected from northeasthern Thailand was examined using random amplified polymorphic DNA (RAPD) technique using twenty primers. The results showed that pollen grains of all three varieties were spheroidal, prolate spheroidal or prolate in shape, isopolar in polarity, 3-colpate in apertures and reticulate in exine sculpturing. The range in diameter of pollen in P. chinense var. chinense, P. chinense var. ovalifolium and P. chinense var. hispidum were 30 – 50µm, 32 – 62.5 µm and 33 – 50 µm, respectively. The pollen morphology cannot be used to distinguish the three varieties of P. chinense where as DNA fringerprints based on RAPD were different. A total of 188 RAPD bands were obtained using six random primers. Of these, 99.47% were polymorphic ranging from approximately 173 to 2,648 base pairs. The geneti