Genetic diversity of the giant tiger prawn Penaeus monodon in relation to trace metal pollution at the Tanzanian coast.
The genetic diversity of giant tiger prawns in relation to trace metals (TMs) pollution was analysed using 159 individuals from eight sites at the Tanzanian coast. The seven microsatellites analysed showed high degree of polymorphism (4-44 alleles). The measured genetic diversity (Ho=0.592±0.047) was comparable to that of populations in the Western Indian Ocean. Apart from that, correlation analysis revealed significant negative associations between genetic diversity and TMs pollution (p<0.05), supporting the genetic erosion hypothesis. Limited gene flow was indicated by a significant genetic differentiation (FST=0.059, p<0.05). The Mantel test rejected the isolation-by-distance hypothesis, but revealed that gene flow along the Tanzanian coast is limited by TMs pollution. This suggests that TMs affect larvae settlement and it may account for the measured deficiency of heterozygosity. This calls for strengthened pollution control measures in order to conserve this commercially important species.
Vrije Universiteit Brussel (VUB), Ecology and Biodiversity, Marine Biology, Pleinlaan 2, 1050 Brussels, Belgium; Sokoine University of Agriculture, Department of Biological Sciences, 3038 Morogoro, Tanzania. Electronic address: ckrumisha@yahoo.com.
Cyrus
C
Rumisha
Vrije Universiteit Brussel (VUB), Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium.
Martine
M
Leermakers
Vrije Universiteit Brussel (VUB), Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium.
Marc
M
Elskens
Sokoine University of Agriculture, Department of Medicine & Public Health, 3021 Morogoro, Tanzania.
Robinson H
RH
Mdegela
Sokoine University of Agriculture, Department of Microbiology, Parasitology and Immunology, Genome Science Center, 3019 Morogoro, Tanzania.
Paul
P
Gwakisa
Vrije Universiteit Brussel (VUB), Ecology and Biodiversity, Marine Biology, Pleinlaan 2, 1050 Brussels, Belgium.
Marc
M
Kochzius
D000818:Animals; D004247:DNA / Q000235:genetics; D051456:Gene Flow / Q000187:drug effects; D014644:Genetic Variation; D019156:Indian Ocean; D019216:Metals, Heavy / Q000032:analysis* / Q000633:toxicity; D018895:Microsatellite Repeats / Q000235:genetics; D033561:Penaeidae / Q000737:chemistry / Q000187:drug effects* / Q000235:genetics; D013636:Tanzania; D014131:Trace Elements / Q000032:analysis* / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity
D019216:Metals, Heavy; D014131:Trace Elements; D014874:Water Pollutants, Chemical; D004247:DNA
East Africa; Genetic population structure; Giant tiger shrimp; Heavy metal pollution; Simple sequence repeats (SSR)