Molecular population genetic study for pantropical plants with seadrifted seeds in aspects of their species integration and speciation

1.木槿及其近缘种：CpDNA分析结果如下。i) 4个亲缘种是由一种带海漂种子的泛热带植物——木槿（Hibiscus tiliaceus）形成的。ii)种子在较广的分布区域内具有长距离传播的能力。(3)美洲大陆两侧的伯南布氏芽孢杆菌具有明显的遗传多样性，并且仅在大西洋种群中有来自H.tiliaceus的遗传渗入。微卫星分析显示：i)基因流动频繁，分布范围很广，某些地区人口局部多样化。ii)巴拿马地峡上可能的花粉基因流动。a)两个亚种间存在明显的遗传分离（ssp）。Pes-caprae和ssp。巴西利亚种)，在形态学上被识别。②美洲大陆东部和西部的种群遗传多样性最大，其次是东太平洋和非洲，但均低于两个亚种之间的水平。3)印度洋和太平洋地区之间没有明显的种群分离，这表明基因流动是通过远距离种子传播的。玫芥：叶绿体基因的系统发育分析表明：i)具有海洋漂流种子的物种具有相同的单倍型。(2)一种单倍型玫瑰花分布在所有的海洋区域。根霉：系统发育分析、叶绿体DNA和种群研究表明：i)美洲大陆两侧红毛豆遗传多样性显著。属于IWP （inwp - west Pacific）种的samoensis在R.mangle的太平洋种群中具有相同的单倍型。

1.Hibiscus tiliaceus and its allied species : CpDNA analysis revealed the followings.i)Four allied species were speciated from a pantropical plants with seadrifted seeds : Hibiscus tiliaceus.ii)Long distance seed dispersal are confirmed over the wide distribution area.iii)Distinctive genetic diversification in H.pernambucensis between both side of American Continents, and introgression from H.tiliaceus only in Atlantic populations.Microsatellite analysis revealed the followings:i)Frequent gene flow over very wide distribution range, and local diversification of population in certain areas.ii)Possible gene flow by pollen over the Isthmus of Panama.2.Ipomoea pes-caprae : AFLP analysis suggested the followings:i)Clear genetic segregation between the two subspecies (ssp.pes-caprae and ssp.brasiliensis) that are morphologically recognized.ii)Genetic diversification of population was largest between Eastern and Western part of America continents, following East Pacific, and Africa, but all of them were less than the level between the two subspecies.iii)No clear segregation of population between the Indian Oceanic and Pacific regions, that suggest gene flow via long distance seed dispersal.3.Canavalia rosea : Phylogenetic analysis of chlroplast genes suggested the followings.i)Identical haplotypes were shared among species with sea-drifted seeds.ii)A haplotype of C. rosea distributes over all the oceanic regions.4.Rhizophora mangle : Phylogenetic analysis chloroplast DNA and population studies suggested the followings.i)Distinctive genetic diversification in R. mangle between both side of American Continents.ii)R.samoensis that belongs to IWP (Indo-West Pacific) species has the same haplotype distributed over Pacific populations of R.mangle.