Allozyme variability of brown trout (Trutta L.) populations across the rhenanian-danubian watershed in southwest germany

Abstract

Using horizontal agarose thin layer gel electrophoresis, 35 allozyme loci were screened in 233 brown trout (Salmo trutta L.) from 11 populations in southwest Germany across the Rhenanian- Danubian watershed. Polymorphism was found at 10 loci, with stocked populations exhibiting significantly increased polymorphism compared with unmanaged stocks (P= 0.219 vs. P= 0.132). Standard genetic distances between populations from different brooks averaged at D = 0.01. Of the total gene diversity of GST = 0.198, only a negligible amount partitioned between Rhenanian and Danubian drainages (Ggt = 0.010). One biallelic locus, LDH-5*, indicated river-specific allele frequencies, with the allele LDH-5* 105 being markedly more frequent within the Danubian drainage system. In contrast, LDH-5*100 was close to fixation in the Rhenanian populations. This locus suggests a phylogeographical relationship of Danubian trout from southwest Germany with brown trout from southeastern Europe rather than with conspecifics of adjacent Rhenanian origin. © 1995 The Genetical Society of Great Britain.