Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.639192
Title: Genetic variation and differentiation in Asian populations of Artemia
Author: Thomas, K. M.
Awarding Body: University College of Swansea
Current Institution: Swansea University
Date of Award: 1995
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Abstract:
A survey of genetic variation in newly discovered Chinese and other Asian populations of Artemia has been carried out using allozyme electrophoresis (20 loci), restriction fragment length polymorphisms in the 16S rRNA mitochondrial gene, and cytological techniques. The principal objectives were to study and analyse genetic variation and differentiation in the Artemia populations examined to clarify the phylogenetic and taxonomic status of the genus and to estimate the extent of genetic variation available for possible exploitation in aquaculture. Mitochondrial DNA studies give results broadly concordant with those from work with allozymes, confirming high nucleotide divergence (12.4-14.9%) between Old and New World populations and substantial nucleotide divergence (4.55%) between Chinese and other Asian populations. The 16S rRNA gene appears to be an informative genetic marker for differentiating between some species in the genus. Length variation and length heteroplasmy were found in the Artemia populations studied. Analysis of the presence or absence of chromocentres makes it possible to differentiate between Old and New World Artermia. The presence of A.franciscana (introduced widely throughout South East Asia) is demonstrated in several of the populations examined. Heteroploidy and aneuploidy are found among the bisexual species A.sinica and A.urmiana and among several diploid and tetraploid parthenogenetic populations. An updated and revised phylogeny of the genus using both allozyme and mtDNA data displays high divergence levels of genetic differentiation among Eastern Old World populations. The considerable genetical reservoirs within populations and the large genetic differences between populations represent both considerable evolutionary capital and a resource potentially of great value in the exploitation of Artermia for aquaculture.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.639192  DOI: Not available
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