Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Genetic Variation in Four Hatchery Populations of Thai Pangas, Pangasius Hypophthalmus of Mymensingh Region in Bangladesh Using Allozyme Marker

Suman Barua
Fisheries Geneticist, North-West Fisheries Resources Development and Management Project, Parbatipur, Dinajpur, Bangladesh.

Mohammad Shafiqul Alam
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh.

Md. Mukhlesur Rahman Khan
Department of Fisheries Biology and Genetics, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh.

Vibeke Simonsen
Department of Marine Ecology, University of Aarhus, Finlandsgade 14, Denmark

Abstract/ Executive Summary:

To investigate genetic variation four hatchery populations (Shambhuganj, Brahmaputra, Anudan and Bhai-Bhai) of Thai pangas (Pangasius hypophthalmus) of Mymensingh region in Bangladesh were analyzed by allozyme electrophoresis. Using six enzymes, nine presumptive loci were identified where three (Est-1*, Gpi- 2* and Pgm*) were polymorphic (p≤ 0.95) in Anudan and Brahmaputra populations and one locus, Est-1*, was polymorphic in Shambhuganj population. No polymorphic locus was found in Bhai-Bhai population. The mean proportion of heterozygous loci per individual was 11.3±8.5% which ranged from 0.0% (Bhai-Bhai population) to 20% (Anudan population). The mean number of allele per locus was 1.3 that ranged from 1.0 (Bhai-Bhai population) to 1.6 (Anudan population). The UPGMA dendrogram showed that the four populations were divided into two groups by the genetic distance, D=0.18 but the populations were not geographically isolated. Finally the results indicated that the Anudan and Brahmaputra populations were showed higher genetic variation whereas Bhai-Bhai population lost their genetic variation completely.

Keywords: Thai pangas (Pangasius hypophthalmus), Hatchery populations, Genetic variation, Allozyme mlliker

Location: Shambhuganj Government Fish Seed Multiplication Farm, Brahmaputra Fish Seed complex, Anudan hatchery and Bhai-Bhai Fish Seed Plant, Mymensingh

Start Date: 00-04-2002

End Date: 00-04-2002

Program Area: Variety and Species

Commodity: Pangus

Objectives:

To clarify genetic variation of P. hypophthalmus using four hatchery populations from Mymensingh region in Bangladesh.

Methodology:

The fingerlings of Thai pang as were collected from four different hatcheries i.e., Shambhuganj Government Fish Seed Multiplication Farm, Brahmaputra Fish Seed complex, Anudan hatchery and Bhai-Bhai Fish Seed Plant, Mymensingh during April, 2002. Details of the sampling localities, number of samples and collection. All the samples were reared in the newly constructed ponds after collection. Twenty individuals from each population were caught randomly after they get a size so that muscle and liver samples could be taken for allozyme work. The muscle and liver tissues were collected from each fish separately and immediately frozen at -20^oC and stored at this temperature until electrophoretic analysis. In the experiment, horizontal starch gel electrophoresis, using citric acid-aminopropylmorpholine buffer (pH 6.1) was used for allozyme work. The enzymes analyzed, abbreviation of enzymes, enzyme patterns, E.C. numbers, tissue types and buffer systems for horizontal starch-gel electrophoresis. Allele frequencies were calculated directly from observed genotypes. The distribution of observed genotypes was compared with that expected, calculated from the Hardy-Weinberg equilibrium using a X²test. When the most common (major) allele existed in a frequency less than or equal to 0.95 at a given locus, this locus was regarded as polymorphic. The mean proportions of heterozygous loci per individual, mean proportion of polymorphic loci per population, average number of alleles per population were calculated so as to show the extent of genetic variability. Coefficient of genetic variation (G_sT) was also calculated in order to estimate diversity between sample lots. Genetic distance values (D) were calculated from allelic frequencies for all possible pairs of sample lots. The analyses of allozyme data were performed using G-Stat, version 3.1 and TREE VIEW. Based on the D-values, a dendrogram was made by the unweighted pair group method using arithmetic average (UPGMA) method.

Source of Information: Pakistan J oumal of Biological Sciences 7 (2): 144-149, 2004 (ISSN I 028-8880)

Article Link (Online Journal):

Funding Source:

Budget:

Total Budget (Tk.) :

Achievement/Findings:

Finally the results indicated that the Anudan and Brahmaputra populations showed higher genetic variation whereas Bhai-Bhai population lost their genetic variation completely.

Knowledge Management: Journal