泡果荠属和阴山荠属(十字花科)的分属界限及两属的分类校订(英文)

Delimitation and revision of Hilliella and Yinshania (Brassicaceae)

泡果荠属Hilliella和阴山荠属Yinshania是十字花科中国特有的两小群植物 ,但是 ,它们的分属界定却一直颇有争议。本文结合前人的研究结果重新对这两群植物做了研究 ,从而进一步确认这两群植物应该界定为两个属 ,即泡果荠属和阴山荠属。文中比较了两属间重要的性状特征 ,并指出它们的主要区别在于 :泡果荠属果实无假隔膜 ,种子较大 ,表面具小瘤状突起 ,染色体倍性为六倍体 ( 2n =6x =42 ) ;而阴山荠属果实有假隔膜 ,种子较小 ,表面具网纹 ,染色体倍性为二倍体 ( 2n =2x =1 2 )。两属其他方面如叶形态、叶表皮结构、被毛类型、地理分布和生境等方面也都存在着一系列区别。这些性状特征的明显不同 ,作为界定两属的界限不仅足够而且清楚。本文对界定两属的观点和界定一属的看法做了详细的分析讨论 ,对两属的属下分类单位也作了校订。长柱泡果荠H .longistylaY .H .Zhang、黎川泡果荠H .lichuanensisY .H .Zhang和广东泡果荠H .guangdongensisY .H .Zhang降级作变种处理。泡果荠属包括有 1 1种和 4个变种。阴山荠属属下仍为两个组 :sect.Yinshania和sect.MicrocarpaY .H .Zhang ,包括 8个种和 2个变种 ;做出 1新组合 :Y .acutangula (O .E .Schulz)Y .H .Zhangvar.gobica (Z .X .An)Y .H .Zhang。文中对两属?

Taxonomic characters for delimitation of Hilliella and Yinshania are discussed. More attention in this study is paid to morphological delimitation of these two genera. The results of the study show that these two genera can be easily separated by two primary morphological features of their fruits and seeds:. Hilliella has eseptate fruits and tuberculate seeds while Yinshania has septate fruits and reticulate seeds. In addition, these two genera also differ in morphology of their leaves I trichomes, sizes of seeds, and their geographical distributions and ecological adaptations as well. Furthermore, both of them have different numbers and ploidy levels of chromosomes. Therefore, Hilliella and Yinshania are retained as two genera in this paper, as was suggested by the previous studies. Hilliella includes I I species, four varieties. U. longistyla Y. H. Zhang, H. lichuanensis Y. H. Zhang and H. guangdongensis Y. H. Zhang are relegated to varieties of H. changhuaensis Y. H. Zhang. Yinshania remains in two sections: sect. Yinshania and sect. Microcarpa Y. H. Zhang including eight species and two varieties. A new combination is proposed: Y. acutangula (O. E. Schulz) Y. H. Zhang var. gobica (Z. X. An) Y. H. Zhang. Descriptions, distributions and keys to the infrageneric subdivisions are provided. Errors and confusions in the previous studies on taxonomy of Hilliella and Yinshania are also discussed and redressed.