Ecology and genetics of the palm Carpoxylon macrospermum from Vanuatu

An extensive survey in 1994 which visited 12 islands (Aneityum, Futuna, Tanna, Erromango, Efate, Tongoa, Epi, Malakula, Ambrym, Pentecost, Ambae and Espiritu Santo), an earlier survey on Espiritu Santo in 1993, and subsequent investigations, documented a total population of the endangered palm, Carpoxylon macrospermum, comprising 154 reproductively mature individuals, ± 145 juveniles and ± 640 seedlings. Of the mature individuals, 122 (80% of total) are known to have been planted in village/garden situations. Naturally occurring mature individuals total 32 and occur on Aneityum, Tanna and Futuna. Two populations on Aneityum and Tanna were studied in detail: the Anetchininbeke site on Aneityum was visited on 9 November 1994 and the Lown'ock site on Tanna was visited on 14 November 1995 - refer to the paper for further details. A total of 114 seeds were collected from 26 sites on the islands Aneityum, Tanna, Malakula, Espiritu Santo and Epi. Of the 114 seeds collected, 86 (from 19 of the 26 collection sites) provided embryos that were in a fit condition for DNA extraction. Seeds from 1994 were mature, fallen seeds that had to hydrated prior to DNA extraction. Those collected in 1995 were mostly taken directly from the palms and the endosperms were still hydrated and the embryos extracted immediately upon arrival at AIMS.Genetic variation within the population was determined by random amplified polymorphic DNA (RAPD) analysis. At only 2 (Lawn'oek and Yeruareng on Tanna) of the 19 sites sampled was any significant variation detected. Seed locations, whether from a naturally occurring population, the number of embryos from which DNA could be extracted and the numbers of seeds providing reliable RAPD patterns with each primer (AP3 to AP13) were recorded: the number of RAPD patterns produced from all seeds, with all primers, was 757.Cluster analysis of RAPD patterns of Carpoxylon macrospermum was carried out. To determine any genetic variation within the population of the endangered palm, Carpoxylon macrospermum.

1994年开展的一项大范围调查共走访了12座岛屿（阿内蒂乌姆岛、富图纳岛、塔纳岛、埃罗芒阿岛、埃法特岛、通戈阿岛、埃皮岛、马拉库拉岛、安布里姆岛、彭特科斯特岛、安巴岛以及圣灵岛），结合1993年针对圣灵岛的前期调查与后续考察，共计记录濒危棕榈物种大籽椰（Carpoxylon macrospermum）的种群总量：含154株繁殖成熟个体、约145株幼株与约640株幼苗。在所有成熟个体中，122株（占成熟个体总数的80%）为人工种植于村落或菜园生境中；自然生长的成熟个体共计32株，仅分布于阿内蒂乌姆岛、塔纳岛与富图纳岛。研究团队对阿内蒂乌姆岛与塔纳岛的两个种群开展了详细研究：1994年11月9日走访阿内蒂乌姆岛的阿内奇尼贝克（Anetchininbeke）样地，1995年11月14日考察塔纳岛的洛诺克（Lown'ock）样地，详细信息请参阅相关学术论文。研究人员从阿内蒂乌姆岛、塔纳岛、马拉库拉岛、圣灵岛与埃皮岛的26个采样点中共采集114粒种子。在采集的114粒种子中，有86粒（来自26个采样点中的19个）获得了符合DNA提取要求的胚。1994年采集的种子为自然脱落的成熟种子，需先进行水合处理后方可开展DNA提取；1995年采集的种子大多直接从植株上获取，其胚乳仍保持水合状态，研究人员抵达澳大利亚分子科学研究所（AIMS）后即刻完成了胚的提取。种群内的遗传变异通过随机扩增多态性DNA（Random Amplified Polymorphic DNA, RAPD）分析进行检测。在19个采样点中，仅塔纳岛的洛诺克（Lawn'oek）与耶鲁阿伦格（Yeruareng）两个样地检测到了显著的遗传变异。研究人员记录了种子采样点信息（是否来自自然种群）、可用于DNA提取的胚的数量，以及每对引物（AP3至AP13）所获得的可靠RAPD扩增条带数；所有引物对所有种子共产生757条RAPD扩增条带。本研究对大籽椰的RAPD扩增条带进行了聚类分析，以明确该濒危棕榈种种群内的遗传变异情况。