适应辐射类群穇属的系统学研究进展

Advances in Systematics of Adaptively Radiated Eleusine Gaertn. (Poaceae)

摘要:

综合花序拓扑学、比较形态学、分子系统发育、细胞遗传学等资料，对适应辐射类群穇属(Eleusine Gaertn.)的系统学研究进展进行了述评。穇属系统位置——Eleusiinae亚族成员得到分子系统发育证据的支持。该属具有3种花序类型、7个基因组类型、多倍体均由二倍体杂交起源、C4植物高度适应半湿润-半干旱镶嵌气候等特征。据可靠化石记载和现代地理分布推断，穇属很可能起源于东非，时间是晚中新世，而适应辐射则发生在上新世-中新世间隔。总的来说，分子系统发育、细胞遗传学、古地质、古气候数据的整合研究能够为穇属多倍体起源和谱系多样化历史提供令人信服的证据。

Abstract:

The advances in systematics of adaptively radiated Eleusine (Poaceae), involving inflorescence typology, comparative morphology, cytogenetics, molecular phylogeny, were overviewed. Systematic position for Eleusine as a member of subtribe Eleusininae has been verified based on molecular phylogenic analysis, the common characters of Eleusine included three subtypes of inflorescences, seven forms of genome, tetraploids originated from hybridization between diploids, C4 grasses adapted to the mosaic climatic region of semi-arid and semi-humid in east Africa. Based on reliable fossil record and currently geographic distribution, it suggest that Eleusine has originated in east Africa during the late Miocene, and radiated during the Pliocene-Pleistocene interval. The integrating investigation of molecular phylogeny, cytogenetics, paleogeology, paleoclimate data could provide evidence for polyploid orgin and lineage diversification of Eleusine.