Population structure and recruitment mechanism of Conger myriaster larvae using otolith microsturucture and mitochondrial DNA sequences

利用耳石微结构和线粒体 DNA 序列研究星鳗幼虫的种群结构和招募机制

• 批准号: 09660204
• 负责人: MOCHIOKA Noritaka
• 金额: $ 2.11万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09660204/
• 关键词: Conger myriaster; Leptocephalus larva; Anguilliformes; Otolith; daily increment; mitochondrial DNA; control region; genetic variability; 集団構造; 耳石微細構造; ストロンチウム; カルシウム

The growth history and recruitment of Conger myriaster were studied, based on growth increments in sagittal otoliths of leptocephali collected from Nobeoka (Miyazaki Pref.), Yatsushiro (Kumamoto Pref.), Aji (Kagawa Pref.), Shimizu (Shizuoka Pref.) and Soma (Fukushima Pref.) in 1996 and in 1998. The deep check was recognized at before metamorphic zone from all specimen. The check was called the "Coastal front mark" in the present study and this mark may be useful as a bench mark in studying the growth history and recruitment mechanism of the species. Examination of otoliths showed that larvae has entered into coastal water at the age of 119.5 days, and metamorphosis occurred at 110-210 days. Hatching dates extended from September to January.Mitochondrial DNA sequences that include a part of the cytochrome b gene to the first half of the control region of 16 C.myriaster leptocephali were determined to evaluate the population structure of the species. A total of 591 nucleotide site, including cytochrome b gene to the first half of the control region, was sequenced from 16 specimens from Nobeoka (Miyazaki Pref.), Yatsushiro (Kumamoto Pref.) and Soma (Fukushima Pref.). Out of 396 nucleotide sites on the control region, 31 (7.8 %) variable, 16 haplotypes being found. Differences between nucleotide sequences ranged between 0.25 and 4.55% with average of 1.88 %, indicating that the control region of the mitochondrial DNA in the species is characterized be high variability. The phylogenetic tree constructed by the neighbor-joining method shows neither significant geographic clusters. This result indicate that the present specimen might come from a single population.

根据 1996 年从延冈（宫崎县）、八代（熊本县）、安治（香川县）、清水（静冈县）和相马（福岛县）收集的细头虫矢状耳石的生长增量，研究了海康星的生长历史和招募情况。 1998年，所有标本均在变质带前发现了深部检查。在本研究中，该检查被称为“沿海前线标记”，该标记可用作研究该物种的生长历史和招募机制的基准。耳石检查显示，幼虫在119.5天龄时已进入沿海水域，并在110-210天时发生变态。孵化日期从9月延长到1月。确定了16 C.myriaster leptocephali的线粒体DNA序列，包括细胞色素b基因的一部分到控制区的前半部分，以评估该物种的种群结构。对来自延冈（宫崎县）、八代（熊本县）和相马（福岛县）的 16 个样本进行了总共 591 个核苷酸位点的测序，包括细胞色素 b 基因到对照区域的前半部分。在控制区域的 396 个核苷酸位点中，发现了 31 个（7.8%）可变的、16 个单倍型。核苷酸序列之间的差异范围为0.25%至4.55%，平均为1.88%，表明该物种线粒体DNA的控制区具有高度变异性。通过邻接法构建的系统发育树没有显示出显着的地理聚类。这一结果表明目前的标本可能来自单一种群。