Systematics of Leguminosae common to Japan and N.America

1995年8月1日至8月31日、1996年9月29日至11月14日和1997年9月28日至10月20日在美国进行了实地工作。本研究共收集了3000份植物标本、150份酒精标本和100份用于提取DNA的干叶标本。（二）1995年12月10日至17日在美国哈佛大学植物标本室、1997年12月3日至22日在美国哈佛大学植物标本室和纽约植物园进行了植物标本室工作。从分支系统、花粉形态和小叶脉序等方面阐明了三棘属植物的分类地位（Ohashi et al.1996）。2. 将2个北美种与6个亚洲种进行了比较，在花、果和块茎的形态上，北美种与亚洲种区分出2个亚属。3. 北美胡枝子属11种在花、果实和种子的形态上与亚洲种有明显区别。4. 对温带豆科植物Cicereae、Trifolieae和Vicieae进行了系统发育分析，包括形态学、孢粉学和化学分类数据（Endo and Ohashi 1996,1997a, b）。形态学方面的研究：证明弯曲属花序结构是一个简化的假花序，并明确了与相关属的结构关系（Nemoto and Ohashi 1996）。2. 北美铁丝菊的花粉形态与亚洲铁丝菊的花粉外叶分层不同。3. 研究了胡枝子（lepedeza, Nemoto and Ohashi, 1997）中闭花配花的形态、变异和属内变异。4. 子叶微孔是豆科植物子叶中发现的一个新的分类特征（Endo and Ohashi 1998）。分子系统发育研究：叶绿体rbcL基因表明，石楠亚族的石楠亚族和石楠亚族是单系的，是石楠亚族的姐妹族（Doyle et al. 1997）。2. 叶绿体rpl2内含子的缺失支持了除Bryinae亚族、Neocollettia亚族和Phylaciun亚族外的大多数Desmodieae族的单一性（Donovan Bailay et al.1997）。3. 对胡枝子中trnL和trnF之间的非编码区域的系统发育分析表明，胡枝子中trnL和trnF之间的非编码区域代表了亚洲和北美之间的早期多样化，表明两大洲之间只有一次迁移事件。4. 木本分离种对枝藤属、紫藤属中trnL和trnF的非编码区序列分化程度大于草本种对胡枝子属和两栖属。少

I.Field works had been made in U.S.A.from 1 Aug.to 31 Aug.in 1995, from 29 Sep.to 14 Nov.in 1996 and from 28 Sep.to 20 Oct.in 1997. About 3000 herbarium specimens, 150 alcoholic specimens and 100 dried leaf samples for extraction of DNA were collected.II.Herbarium works had been made in U.S.A.from 10 Dec.to 17 Dec.1995 in Harvard University Herbaria and from 3 Dec.to 22 Dec.1997 in Harvard University Herbaria and New York Botanical Garden.III.Results of our researches in this project are summarized below.A.Taxonomic researches : 1. Taxonomic position of Trifidacanthus was clarified by branching system, pollen morphology and leaflet venation (Ohashi et al.1996) . 2. Two North American species of Apios were compared with six Asian species, and two subgenera were recognized in Norht American species distinguished from Asian ones in morphology of flowers, fruits and tubers. 3. Eleven species of North American Lespedeza were distinguished from Asian species in morphology of flowers, fruits … More and seeds. 4. The phylogenetic analysis was done on the temperate legume species, i.e., Cicereae, Trifolieae, and Vicieae, with morphological, palynological, and chemotaxonomical data (Endo and Ohashi 1996,1997a, b).B.Morphological researches : Inflorescence structure of Campylotropis was shown to be a reduced pseudoraceme and the structural relationships with the related genera were clarifited (Nemoto and Ohashi 1996) . 2. Pollen morphology of North American Desmodium was shown to be different from Asian ones in exine stratification. 3. Morphology and variation of cleistogamous flowers and the infrageneric variation were clarified in Lespedeza (Nemoto and Ohashi 1997) . 4. Cotyledon areole was discovered as a new taxonomic character in legume cotyledons (Endo and Ohashi 1998) .C.Molecular phylogenetic researches : 1. The chloroplast rbcL gene showed that subtribe Lespedeziinae and Desmodium of tribe Desmodieae are monophyly and sister to tribe Phaseoleae (Doyle et al. 1997) . 2. The loss of chloroplast rpl2 intron supported the monophyly of most of tribe Desmodieae except subtribe Bryinae, Neocollettia and Phylaciun (Donovan Bailay et al.1997) . 3. The phylogenetic analysis of a non-coding region between trnL and trnF in Lespedeza represented the early diversification between Asia and North America, and it suggests a scenario of only one event of migration between both continents. 4. The degree of sequence divergence of the ono-coding region between trnL and trnF was larger in woody disjunct species pairs of Cladrastis, Wisteria than herbaceous Lespedeza and Amphicarpaea. Less