小麦族植物的属间亲缘和系统发育的探讨

STUDIES ON RELATIONSHIPS AMONG THE GENERA AND PHYLOGENESIS OF THE TRIBE TRITICEAE

本文研究了国产及引进的小麦族植物共17属。以花序形态演化为基础,结合叶表皮及成熟胚的解剖结构,论述了小麦族下各属的亲缘关系,提出了本族植物的系统演化树系图。作者首次以花序、小穗,小花三级结构相结合的观点分析了小麦族花序的形态演化;叶表皮结构的变化与花序演化基本同步;成熟胚的结构在小麦族中分化不大,但胚芽卷曲状况及其所含维管束数目对本族的系统安排仍有价值。综上述研究,作者将小麦族划分为3个亚族:(1)小麦亚族中小麦属、山羊草属、簇毛麦属、旱麦草属、异花草属及黑麦属彼此亲缘关系较近,并处于本族系统演化的较高位置;偃麦草属和赖草属亦与小麦属有较近的亲缘关系;冰草属、鹅观草属和披碱草属是本亚族中距小麦属较远的类群。(2)大麦亚族在本族的系统发育中有相对独立性,但赖草属和披碱草属与此亚族下某些属在各性状上均有联系,可认为是沟通两亚族间亲缘关系的类群。(8)柱穗麦亚族仅含柱穗麦属,与小麦亚族亲缘较近,系统位置亦较高。

In the present paper, 17 native and introduced genera of Triticeaehave been studied. Based on the inflorescence evolution and the struc- ture of abaxial epidermis of leaf and of the mature embryo, the relation-ships among the genera of Triticeae have been explored, and the phy-logenetic chart of this tribe is proposed. With the viewpoint of combining inflorescence with its spikelets andflorets, the inflorescence evolution in this tribe have been analysed.The evolutionary steps of the epidermis structure of leaf agree with tho-se of inflorescence. In general, the structure of mature embryo differslittle in Triticeae, but the twisting states of embryonic buds and thenumber of vascular bounds they contain are still significant to the ar-rangment of taxonomic system of this tribe. As a conclution, Triticeae is divided into 3 subtribes: (1) SubtribeTriticinae, Triticum, Aegilops, Haynaldia, Eremopyrum,Heteranthelium and Se-cale which subordinate to this subtribe have mutually close relations,and own the high position in the phylogeny of the tribe; Elytrigia andLeymus also have close relations to Triticum; Agropyron, Roegneria andElymus are relatively distant to Triticum in this subtribe. (2) SubtribeHordeinae is somehow independent in the phylogeny of Trititceae, butLeymus and Elymus show relations with some genera of this subtribe byvarious features, and thus, can be regarded as the bridge between thetwo subtribes. (3) Subtribe Henrardiinae contains only Henrardia, it isrelatively close to Triticinae and advanced in the phylogenesis.