Allozyme variability in brown trout <i>Salmo trutta</i> in Chile

Abstract

1. Brown trout ova were imported during the last century from different locations in Europe to establish populations in Chilean rivers (South America). The rivers are currently occupied by naturalized populations that have adapted to very different environmental conditions, such as areas of semi‐desert in the north, or rainy and cold areas in the south. 2. In this first study in this geographical area, electrophoretic variability of proteins encoded by twenty‐five loci was screened in seven populations from northern to southern Chile. 3. The results show significant heterogeneity of allelic frequencies between populations in seven of eleven polymorphic loci detected. The estimated value of genetic diversity 0.1274 ( H T ) is higher than that observed in populations from areas of natural distribution of this species. However, only 12.64% of this genetic diversity was found between samples ( G ST ), indicating a low genetic divergence among Chilean populations. The observed associations among the Chilean and ‘modern’ group of European populations suggests the probable origin of the new populations.