碩士 / 國立屏東科技大學 / 水產養殖系所 / 96 / The Sparidae fishes are the main economical resource of conventional fishing and the in extensive farming distributed around the world. Picnic sea bream (Acanthopagrus berda) inhabits estuaries and coastal waters throughout the Indian Ocean, West Pacific Ocean, and Red Sea. It is an important species of recreational fisheries in estuarine and coastal waters of Taiwan. Due to the drastically decrease in wild populations, there is an urgent need to determine strategies of the conservation based on study of population structure. This research includes: (1)To determine either genetic differentiation among five populations and the geographic on gene flow between population by juveniles estimation drift to other population depend on the current transport (2)To understand of genetic differentiation between A. berda populations distributed the Northern and the Southern hemispheres. (3) To distinguish A. berda and A. taiwanensis in Dapeng Bay based on morphometric and molecular technique. A total of 224 of A. berda specimens were collected from Tanshui, Tungshih, Penghu, and Dapeng Bay in the Western Taiwan and Townsville in the northeastern Australia and 39 of A.
taiwanensis specimens were collected from the Dapeng Bay. Genetic variations among these five populations were examined by eight polymorphic microsatellite loci Ab-A, B, E, G, H, I, J, and L, and mitochondrial DNA. The allelic size of the eight loci within the five populations ranged from 79 bp (Ab-J) to 179 bp (Ab-A) in length. All loci were polymorphic. Total allelic numbers (na) in each population ranged from 66 (Townsville) to 127 (Dapeng Bay). The means of observed (Ho) and expected heterozygosity ranged from 0.44 vs. 0.64 (Townsville) to 0.70 vs. 0.82 (Dapeng Bay). We assume that the lower genetic diversity resulted from effects of inbreeding or overfishing. Additionally, from the results of two molecular markers, higher genetic similarities were found among four populations in Taiwan when compared with the population in Townsville. These results suggested a significant genetic differentiation between A. berda populations in the Northern and the Southern hemispheres. The reason for the genetic differentiation is attributed to the ocean current conduction and geographic isolation. Results of a principle components analysis (PCA) based on morphometric data indicated the significant distinction between sympatric A. berda and A. taiwanensis. The interspecific genetic distance of the cytochrome (Cyt) b gene (0.118 ± 0.01) was higher than the respective intraspecific distances (0.003 for A. berda and 0.007 for A. taiwanensis). FST (0.134) and RST (0.404) where examined from microsatellite data and indicated significant differentiation between two species. All results for the morphometrics, mitochondrial DNA and microsatellite DNA analyses confirmed the presence of two species, A. berda and A. taiwanensis.
| Identifer | oai:union.ndltd.org:TW/096NPUS5086003 |
| Date | January 2008 |
| Creators | Wan-Lin Tsai, 蔡宛霖 |
| Contributors | Mei-Chen Tseng, 曾美珍 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 109 |
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