The production of sexual and asexual larvae within single broods of the scleractinian coral, Pocillopora damicornis
The production of sexual and asexual larvae within single broods of the scleractinian coral, Pocillopora damicornis
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石珊瑚 (Pocillopora damicornis) 单窝内有性和无性幼虫的产生
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
C. Dai
中科院分区：
文献类型：
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作者：
Shang;C. Dai
通过对台湾南部的成体珊瑚群进行详尽的抽样研究，研究了两个栖息珊瑚 Pocillopora damicornis 种群的基因型组成。此外，从每个群体内的单个亲本收集的 1,000 多个育雏幼虫中随机选择了 100 只幼虫。使用 7 个多态性微卫星标记，发现两个群体都具有高度克隆性，并鉴定了 7 个克隆谱系。一个克隆谱系 (C1) 在两个研究领域均占主导地位，占所有采样集落的 54.9%，而其他 6 个克隆谱系中的任何一个所占比例不超过 5%。从每个亲本中随机抽取 100 只幼虫进行基因分型，克隆繁殖程度很高，分别仅发现 29 只和 6 只幼虫与其亲本存在基因型差异。在 35 种基因型不同的幼虫中，33 种被认为来自有性生殖，2 种被认为是经历了体细胞突变的克隆繁殖体。在两个有性幼虫阵列之一中还发现了两个基因型相同的幼虫，表明多胚现象可能存在。成虫群体和孵卵幼虫中克隆性的高比例表明，无性繁殖的幼虫可能对当地种群的招募做出了重大贡献。研究区密集的大角鹬克隆种群有利于克隆繁殖体在受到干扰后快速重新定殖。
The genotypic compositions of two populations of the brooding coral, Pocillopora damicornis, were studied by exhaustive sampling of adult colonies on a fine scale in southern Taiwan. In addition, 100 larvae were randomly selected among more than 1,000 brooded larvae collected from a single broodparent within each population. Using 7 polymorphic microsatellite markers, both populations were found to be highly clonal, and 7 clonal lineages were characterized. One clonal lineage (C1) dominated both study areas and comprises 54.9% of all colonies sampled, while any of the other 6 clonal lineages represented no more than 5%. Among the 100 larvae randomly selected for genotyping from each broodparent, the extent of clonal reproduction was high, and only 29 and 6 larvae, respectively, were found to be genotypically different from their broodparent. Among the 35 genotypically distinct larvae, 33 were thought to be derived from sexual reproduction, and 2 were assumed to be clonal propagules that had undergone somatic mutations. Two genotypically identical larvae were also found in one of the 2 sexually derived larva arrays, indicating the possible existence of polyembryony. The high proportions of clonality in both adult colonies and brooded larvae suggest that asexually produced larvae might significantly contribute to the recruitment of local populations. The dense clonal population of P. damicornis in the study area favors the quick recolonization view of clonal propagules after disturbances.