Avicennia marina (Forssk.) Vierh is distributed in patches along the Farasan archipelago coast and is the most common mangrove species in the Red Sea. However, to date, no studies have been directed towards understanding its genetic variation in the Farasan archipelago. In this investigation, genetic variations within and among natural populations of Avicennia marina in the Farasan archipelago were studied using 15 microsatellite markers. The study found 142 alleles on 15 loci in nine populations. The observed (Ho) and expected (He) heterozygosity values were 0.351 and 0.391, respectively, which are much lower than those of earlier studies on A. marina in the Arabian Gulf. An inbreeding effect from self-pollination might explain its heterozygote deficiency. Population genetic differentiation (F_ST = 0.301) was similar to other mangrove species. Our findings suggest that the sea current direction and coastal geomorphology might affect genetic dispersal of A. marina. The more isolated populations with fewer connections by sea currents exhibited lower genetic variation and differentiation between populations. The genetic clustering of populations fell into three main groups—Group 1 (populations of Farasan Alkabir Island), Group 2 (populations of Sajid Island), and Group 3 (mix of one population of Farasan Alkabir Island and a population of Zifaf Island). More genetic variation and less genetic differentiation occurred when the population was not isolated and had a direct connection with sea currents. Both of these factors contributed to limited propagule dispersal and produced significant structures among the population. It is expected that the results of this research will be useful in determining policy and species-conservation strategies and in the rehabilitation of A. marina mangrove stands on the Farasan islands in an effort to save this significant natural resource.

中文翻译：

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法拉桑群岛红树林物种（Avicennia marina（Forssk。）Vierh）的空间结构和遗传变异

Avicennia marina（Forssk。）Vierh分布在Farasan群岛沿岸的斑块中，是红海中最常见的红树林物种。然而，迄今为止，还没有研究针对了解法拉桑群岛的遗传变异。在这项调查中，使用15种微卫星标记研究了法拉桑群岛Avicennia滨海自然种群内部和之间的遗传变异。该研究在9个人群的15个基因座上发现了142个等位基因。观察到的（Ho）和预期（He）杂合度值分别为0.351和0.391，远低于以前对滨海曲霉的研究。在阿拉伯海湾。自花授粉的近交效应可以解释其杂合子缺乏。种群遗传分化（F _ST = 0.301）与其他红树林物种相似。我们的发现表明，海流方向和沿海地貌可能会影响滨海曲霉的遗传扩散。。与海流联系较少的更多孤立种群显示出较低的遗传变异和种群间分化。人群的遗传聚类分为三个主要组：第1组（Farasan Alkabir岛的人口），第2组（Sajid岛的人口）和第3组（Farasan Alkabir岛的一个人口和Zifaf岛人口的混合）。当种群不是孤立的并且与海流有直接联系时，发生更多的遗传变异而较少发生遗传分化。这两个因素都导致了繁殖体的有限传播，并在人群中产生了重要的结构。预期这项研究的结果将对确定政策和物种保护策略以及滨海曲霉的恢复有用。 红树林屹立在Farasan群岛上，以保存这一重要的自然资源。