福建沿海巨蛎属(Crassostrea)牡蛎的种类及其分布

福建省位于我国东南沿海, 海岸线曲折, 港湾众多, 有多条河流入海, 适宜牡蛎栖息繁衍, 是我国牡蛎资源最丰富的地区之一。迄今关于福建沿海牡蛎种类组成及分布情况的研究报道尚少, 鉴于近20余年福建主要海湾经历了高强度的牡蛎养殖, 有必要了解福建沿海牡蛎自然群体的物种组成和数量占比等自然种质资源状况。基于现场调查取样, 结合采用多重种特异性PCR、ITS2杂交种鉴定和CO I测序共同鉴定福建沿海巨蛎属(Crassostrea)牡蛎种类及其分布情况。研究结果表明, 从福建沿海由北至南牡蛎野生种苗海区的19个采样点共960个样品中发现3种巨蛎属牡蛎, 分别是福建牡蛎(Crassostrea angulata)、熊本牡蛎(C. sikamea)和香港牡蛎(C. hongkongensis), 并未发现以往报道的近江牡蛎(C. ariakensis)。其中福建牡蛎(607个)占63.23%、熊本牡蛎(343个)占35.73%、香港牡蛎(10个)占1.04%。除个别采样点外, 福建牡蛎和熊本牡蛎在各采样海区均有分布。香港牡蛎仅在泉州湾河口湿地自然保护区(新发现群体)有少量分布。研究结果揭示的福建沿海地区巨蛎属的物种种类及其分布为后续开展牡蛎遗传多样性分析和遗传分化等种群遗传研究提供了关键基础资料, 为牡蛎种质资源的保护和利用打下重要基础。

THE SPECIES AND DISTRIBUTION OF CRASSOSTREA OYSTER IN FUJIAN COAST

Fujian Province is located on the southeast of China facing the East China Sea. The irregular coastline forms numerous bays with several sea-going rivers, which is suitable for living and reproduction of oysters. It is one of the regions with the most abundant natural oysters in China. At present, there are few reports on the composition and distribution of oyster species along the coast of Fujian Province. Given that the main bays of Fujian Province have experienced high-intensity oyster culture in the past 20 years, it is necessary to understand the natural species diversity along the coast of Fujian Province. Therefore, based on field surveys and sampling, we used multiplex species-specific PCR, identification of ITS2 nuclear gene hybrids, and CO I sequencing to identify Crassostrea oyster species from the coastal region of Fujian Province and to determine the distribution of specific species. Results show that three species of Crassostrea, namely C. angulata, C. sikamea, and C. hongkongensis, were found in a total of 960 samples collected from 19 sites of typical natural oyster seed-production areas along the coast of Fujian Province. No C. ariakensis was found as previously reported. Among them, C. angulata (607) accounted for 63.23%, C. sikamea (343) for 35.73%, and C. hongkongensis (10) for 1.04%. C. angulata and C. sikamea were the dominant species and distributed in the majority sampling areas. However, C. hongkongensis was merely found in the Quanzhou Bay Estuary Wetland Nature Reserve, which was newly discovered natural population. The species and distribution of oysters in the Fujian coastal area revealed in this study provide key basic data for the analysis of genetic diversity and the genetic differentiation of oyster populations, which pave the road for protection and utilization of oyster germplasm resources.