中国禾本科植物新资料(Ⅱ)

Notes on the Family Poaceae in China (Ⅱ)

摘要:

报道了我国境内新发现的2种外来禾草：宽叶臂形草[Brachiaria platyphylla (Munro ex C. Wright) Nash]和车前臂形草[B. plantaginea (Link) Hitchc.]，这2物种有时被处理为尾稃草属(Urochloa)的成员。依据小穗第一颖背部具向轴性，第二外稃先端不具小尖头的形态特征，认为他们更接近于国产臂形草属(Brachiaria)的物种，编制了他们与国产近缘物种、属的分类检索表，并讨论了2外来种的潜在入侵风险。

Abstract:

Two exotic weeds, Brachiaria platyphylla (Munro ex C. Wright) Nash and B. plantaginea (Link) Hitchc, are firstly reported in China. They share the characters of the lower glume adaxial and the upper lemma obtuse with Chinese Brachiaria species, without the characters of the abaxial lower glume, long mucro upper lemma of Urochloa species. The taxonomic differences among these two new record grasses and the other Brachiaria species from China are edited in one key. Their potential invasion risks are discussed.