Summary: | We examined the genetic population structure of the european hake (Merluccius merluccius) using electrophoretically detectable population markers in 35 protein loci. Samples were collected from 7 locations in the Atlantic Ocean and Mediterranean Sea. Six loci were polymorphic using the 0.05 criterion of polymorphism. Sample heterozigosities ranged from 0.052 to 0.072 and averaged 0.0625. In this study, significant allele frequency differences were detected between Atlantic and Mediterranean populations in three polymorphic loci: GAPDH-1*, GPI-2* and SOD-1*. Two major genetic groups were considered: a North-Atlantic stock and the Mediterranean stock. The Nei genetic distance, D, (based on 33 loci) between samples from these two groups ranged from 0.002 to 0.006. Genetic differenciation between these areas appears to reflect the barrier effect of Strait of Gibraltar. On average over loci, 96.92 % of the total gene diversity was contained within samples, 0.23 % expressed differences among locations within areas, and 2.64 % differences between regions. A review of morphological variation together with the genetic data presented here suggest that the populations of hake from these areas are subdivided into two different stocks: the North-Atlantic stock and the Mediterranean stock. The most conservative approach to the management of these stocks is to consider the Atlantic and Mediterranean stocks independently from one another L'anàlisi electroforètica de mostres pertanyents a Port de la Selva, Palamós, Blanes, Sant Carles de la Ràpita, Gandia, Huelva i Donostia ha permès de detectar 35 loci electroforètics dels quals 16 presenten variabilitat genètica i 6 són polimòrfics: GAPDH-1*, GPI-1*, GPI-2*, G3PDH* SOD-1* i CAT*. El grau de diferenciació genètica trobat per aquests loci a les diverses localitats mostrejades indica que existeixen diferències significatives entre les poblacions mediterrànies i atlàntiques de lluç, per la qual cosa podem afirmar que aquestes poblacions formen part de dos estocs diferents. ...
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