A study of evolution of plants in South Pacific islands

本研究的目的是为了更好地了解南太平洋岛屿植物物种的进化和繁殖机制。我们的输出如下：本文首次报道了新喀里多尼亚特有种、代表被子植物进化第一个分支的三毛Amborella trichopoda的胚胎学研究。通过与已有资料的比较，阐明了与安博亚属相邻分支的仙女亚属（Nymphaeales）和百合亚属（Illiciales）的胚学特征的单象性。（Tobe et al. 2000）本文报道了首个毛线虫的核型分析。它有2n=26 x=13。在此基础上，我们讨论了Amborella的染色体数可能来源于x=14，被子植物的原始染色体数可能是x=7。（Oginuma et al. 2000）。本文在查阅文献的基础上，对月桂属植物的胚胎学研究进展进行了综述。月桂属植物分布于东、新世界热带地区，包括南太平洋岛屿。此外，在现有的月桂属植物分子树的基础上，探讨了月桂属植物胚胎学特征的进化，同时明确了哪些植物类群和哪些胚胎学特征需要研究。（Kimoto and Tobe 2001）。首次利用rbcL和matK的叶绿体DNA序列对分布于南太平洋岛屿（和澳大利亚）的木麻黄科植物进行了系统发育研究。结果显示：（gyynmostoma (Ceuthostoma (Allocasuarina Casuarina))）)等关系。（Sogo et al. 2001）。首次对生长在日本伊里奥莫特岛的红树8属8种进行了花香分析。我们发现了61种化合物，并讨论了它们与传粉昆虫的关系。（Azuma et al. 2002）。本文首次对台湾14种海棠进行了体细胞染色体核型分析。在此基础上，我们讨论了它们的进化过程，并明确了台湾有5个新种。（Oginuma and Peng 2002）。少

The purpose of the present study is to contribute to better understanding of evolution and reproductive mechanisms of plant species growing in South Pacific islands. Our output is as follows.1. We presented the first embryological study of Amborella trichopoda representing the first branch of angiosperm evolution, which is an endemic species in New Caledonia. Compared to already known information on Nymphaeales and Illiciales which represent branches next to Amborella, symplesiomorphies of embryological characters were clarified. (Tobe et al. 2000).2. We presented the first karyotype analysis in Amborella trichopoda. It has 2n=26 with x=13. Based on analyses, we discussed that the chromosome number of Amborella is likely to have been derived from x=14 and that a primitive chromosome number of angiosperms is likely to be x=7. (Oginuma et al. 2000).3. A review of embryological studies on Laurales which are distributed worldwide in tropics of Old and New World including South Pacific isla … More nds was presented on the basis of a literature survey. In addition, in the light of molecular trees available for the Laurales, we tried to discuss an evolution of embryological characters, and simultaneously clarified what plant groups and what embryological characters need investigations. (Kimoto and Tobe 2001).4. An overall phylogenetic study of Casuarinaceae that are distributed in South Pacific islands (and Australia) was conducted for the first time using chloroplast DNA sequences of rbcL and matK. Results showed relationships like (Gynmostoma (Ceuthostoma (Allocasuarina Casuarina))). (Sogo et al. 2001).5. We analyzed floral scent in 8 species of 8 genera growing hi mangrove of Iriomote islands, Japan for the first time. We found 61 chemical compounds and discussed relationships with polinators. (Azuma et al. 2002).6. Fourteen species of Begonia from Taiwan were analyzed with respect to karyotypes of their somatic chromosomes for the first time. Based on results, we discussed their evolution, and clarified that 5 new species exist in Taiwan. (Oginuma and Peng 2002). Less