A Taxonomic Study of Eragrostis Wolf (Poaceae) in Taiwan

• Main Authors: Kuan-Yin Liu, 劉冠吟
• Other Authors: Chang-Sheng Kuoh
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/39961812119110220896

碩士 === 國立成功大學 === 生物多樣性研究所 === 97 === The grass family (Poaceae or Gramineae) is the fourth largest flowering plant family and contains about 11 000 species in 800 genera worldwide. The genus Eragrostis, contain 400 or more species, is the largest genus within the subfamily Chloridoideae. There were many different taxonomic treatments for this diversity genus mostly by their gross morphology. In this taxonomic study on Eragrostis of Taiwan, we find that growth pattern of culm, morphology of leaf, inflorescence, spikelet, floret, and caryopsis respectively are reliable characters, and the distribution of gland and hair are the most valuable characters for classification. In this study, 21 species in the genus Eragrostis of Taiwan were treated. In which, some species name are retreated as the followings: E. bulbillifera Steud. was treated as synonym of E. brownii Kunth; E. poaeoides P. Beauv. was treated as synonym of E. minor Host, meanwhile three new record species were described：E. atrovirens（Desf.）Trin., E. curvula（Schrad.）Nees, and E. tenuifolia (A. Rich.) Hochst., and two uncertain species（E. sp.1 & E. sp.2）need further study. The distribution of gland and cilia, the morphology of caryopsis, and the persistence of glumes and lemma are the most valuable characters for classification within the section Eragrostis. The model of florets falling-off, the morphology of inflorescence, and the growth pattern of culm are also provided for identification. Anatomical characters, such as cell type and pattern of leaf epidermis, sclerenchyma and bulliform cell of leaf cross section are different between taxa. On the other hand, these morphological data were entered as a DELTA database and then the cluster analysis was conducted by UPGMA and PCO. The results show that there are 4 distinct groups within 21 species of this genus.