MORPHOLOGICAL CHARACTERIZATIONS OF BUD, ANTHER AND MICROSPORES IN NGOC LINH GINSENG- PANAX VIETNAMENSIS HA ET GRUSHV. VAR. VIETNAMENSIS (ARALIACEAE)

Ngoc Linh ginseng (Panax vietnamensis Ha et Grushv. var. vietnamensis) is a valuable and endemic medicinal plant of Vietnam. Propagation of Ngoc Linh ginseng plants is mainly dependent on seeds produced via self-fertilization. However, little is known about reproduction development in Ngoc Linh ginseng. In this study, several morphological characteristics of inflorescences, floral buds, anthers, and microspores were observed and described. The results showed that floral buds ranged from 0.5 to 4.4 mm, anthers from 0.48 +/- 0.28 to 1.56 +/- 0.45 mm, and microspores from 20.82 +/- 2.49 to 41.22 +/- 1.44 mu m. A strong correlation between bud length, anther length and developmental stage of microspores were shown, which were 0.905 and 0.781, respectively. Moreover, microspores of different developmental stages in a single anther were observed. These study results can be used to improve the sexual reproduction of this ginseng.