Allozyme Variation in the Large-scale Mullet Liza Macrolepis (Perciformes: Mugilidae) from Coastal Waters of Western Taiwan

臺灣沿海岸大鱗鯔異構酶之變異

李信徹(Sin-Che Lee) ； 鄭蕙玲(Hui-Ling Cheng) ； 張羢悌(Jung-Ti Chang)

《Zoological Studies》 35卷2期 (1996/04) Pp. 85-92

摘要

本文報導採自臺灣西海岸淡水河口、澎湖、高雄愛河及東港大鵬灣大鱗鱗異構酶之分析比較。上述四個地區樣品間所估算出之遺傳相似度（I=0.992-0.999）極高，足證彼應同屬一族群。由sAAT-1、CK-B、GPI-A、GPI-B、LDH-C、IDHP-A、sMDH-A、sMDH-B、ME-1及MPI-1等十個基因座雜合率（P99）之比較，發現除了大鵬灣之GPI-B及淡水河口之IDHP-A外，其餘八個基因座均符合哈溫定律。綜合比較四個樣品之雜合率，大鵬灣（0.044）及淡水河口樣品（0.043）遠高於高雄愛河（0.029）及澎湖（0.028），可能緣於大鵬灣受到較嚴重的污染衝擊（尤其是有機性的）及淡水河口之較低溫環境。再則由於大鵬灣樣品MPI-1基因座之高頻度現象可能引致大鵬灣魚群與其它三處間有明顯的遺傳變異現象。大鵬灣因屬半封閉之潟湖，內中魚群與外海魚群間之基因交流不若其它三處顯著，使得大鵬灣大鱗鯔呈現偏高之近交係數。

關鍵字

族群遺傳 ； 異構酶比較 ； 大鱗鯔

並列摘要

Allozyme variation was studied in the large-scale mullet Liza macrolepis collected from 4 sites: 3 sites on the west coast of Taiwan, the Tanshui estuary, the Kaohsiung River (Love River) and Dapong Bay (Tungkang); and 1 site about 50 km off the west coast of Taiwan, the Penghu Islands. The genetic similarities among these 4 localities are rather high (0.992-0.999), indicating that they belong to the same population. The inter-sample comparisons of heterozygosity based on 10 polymorphic loci (sAAT-1, CK-B, GPI-A, GPI-B, IDHP-A, LDH-C, sMDH-A, sMDH-B, ME-1 and MPI-1) under the 0,99 criterion revealed that most loci conform with the Hardy-Weinberg Equilibrium, except those at GPI-B from Dapong Bay and IDHP-A from the Tanshui estuary, Analysis of overall mean heterozygosities among 4 inter-sample comparisons revealed that the samples from Dapong Bay and the Tanshui estuary have higher values (0.044 and 0.043, respectively) than those from the Kaohsiung River and Penghu (0,029 and 0.028, respectively), probably due to heavy organic pollution in Dapong Bay and colder temperatures in the Tanshui estuary. Comparisons of overall FST (local subpopulation differentiation) of Dapong Bay with those of the three other locations indicate a moderate genetic differentiation which is mainly contributed by the unusually high allele frequency of the MPI locus, A higher inbreeding coefficient (Fls) in the Dapong sample corresponds to the high inbreeding potential at this site, probably due to its nearly land-locked habitat, which limits the exchange of individual fish between the bay and the open coast.

並列關鍵字

Population genetics ； Allozyme comparisons ； Large-scale mullet