Developmental and Structural Section
Tsai, Meng-Ying , Chen, Su-Hwa , Kao, Wen-Yuan .
A histological study of microsporogenesis and pollen development of Oxalis corymbosa and Oxalis corniculata inTaiwan.
Oxalis corymbosa DC., an exotic species in Taiwan, produces two different colors (yellow and white) of anthers. No pollen is found in white anthers, while low pollen viability in yellow anthers (~4%). In contrast, O. corniculata, the native congener of O. corymbosa, produces yellow anthers with relatively high pollen viability (~50%). To understand the failure of microsporogenesis and pollen development in O. corymbosa, we made histological comparison of androecium ontogeny in three types of anthers (yellow anthers of O. corniculata and yellow or white anthers of O. corymbosa).The microsporangium ontogeny of O. corniculata can be assigned into six stages: sporogenous tissue, microspore mother cell (MMC), tetrad, free microspore (uni-nucleate microspore), bicellular pollen grain and mature pollen grain stage. At sporogenous tissue and MMC stage, no significant difference was found in the two Oxalis species. In white anthers of O. corymbosa, obvious vacuolated/enlarged cells of middle layer were observed at tetrad and free microspore stage. In addition, at free microspore stage, almost all microspores within the white anthers had degraded cytoplasm and less deposition of sporopollenin-like materials on the wall of microspores. Subsequently, the aggregated microspores collapsed and deformed. As a result, no healthy pollen grains were observed in white anthers of O. corymbosa. In yellow anthers of O. corymbosa, many deformed microspores were observed after tetrad stage. Besides, some microspores had three nucleuses at free microspore stage. Finally, few normal pollen grains were developed in yellow anthers of O. corymbosa. Accordingly, the developmental failure of free microspore in O. corymbosa might result from meiotic problem at tetrad stage.
Log in to add this item to your schedule
1 - National Taiwan University, Institute Of Ecology And Evolutionary Biology, Rm. 1230, Life Science Building, 1, Sec. 4, Roosevelt Rd. Taipei 106, Taiwan, Tapei, N/A, 10617, Taiwan
2 - National Taiwan University, Department of Life Science, Rm 1136, Life Science Building, 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan
3 - National Taiwan University, #1, Roosevelt Rd. Sec.4, Taipei, 10617, Taiwan
Presentation Type: Poster:Posters for Sections
Location: Battelle South/Convention Center
Date: Monday, July 9th, 2012
Time: 5:30 PM