Application of mtDNA markers for European huchen (Hucho hucho Linnaeus, 1758) management in Poland

Abstract

Four broodstocks of European huchen (Hucho hucho) from Poland, Germany, Slovakia, and Ukraine were investigated using five selected fragments of mtDNA. The mitochondrial DNA sequence analysis was successfully applied to the Polish and German broodstocks of European huchen for the first time. A very low haplotype (h = 0.097) and nucleotide (π = 0.00013) diversity across 3573 bases of mtDNA fragments (partial regions of NADH-1, ATPase 6, Cytochrome b, evidenced by three closely related mtDNA haplotypes were found. The analysis of pairwise genetic differentiation (Fst) displayed a statistically significant differentiation between German (clade A) and the rest of examined broodstocks (clade B), clustering them into two separate groups. Moreover, the applied mtDNA markers did not reveal any differences among fish from the clade B, suggesting that other markers should be used to display a deeper genetic background of the studied broodstocks. The two clusters of European huchen distinguished under the current study should be considered as distinct management units by managers, who may be tempted to transport brood fish or yearlings across the range of European huchen distribution. It means that stocking material and spawners of European huchen from the upper parts of the Danube River (Clade A) should not be mixed with those from the lower parts (Clade B). Moreover, for any supplementation of broodstocks in order to increase their genetic variability only the fishes within the described management units should be used.

Conservation genetics study of huchen in Slovenia recommends river system‐based management and indicates self‐sustainability of the middle Sava population

“…Genetic differentiation among these three populations is even larger than that observed among geographically distant huchen brood stocks from hatcheries in Germany, Poland, Slovakia, and Ukraine (Kuci nski et al, 2015a). By contrast, NADH-1 analysis showed, as in previous mtDNA studies of huchen (Weiss, Mari c & Snoj, 2011;Kuci nski et al, 2015b), an extremely low level of polymorphism, which isin terms of nucleotide and haplotype diversitycomparable to the values obtained for wild huchen in Serbia (Mari c et al, 2014) and brood stocks in central and eastern Europe (Kuci nski et al, 2015b).…”

“…Thus, an obvious conflict of interests exists between hydropower exploitation and protection of huchen habitat. Genetic analysis of wild populations and brood stocks of huchen across most of its range have shown extremely low genetic diversity, low intraspecific divergence and relatively weak natural fragmentation (Geist et al, 2009;Weiss, Mari c & Snoj, 2011;Mari c et al, 2014;Kuci nski et al, 2015a;Kuci nski et al, 2015b). Although surveyed, huchen from Slovenia (Weiss, Mari c & Snoj, 2011) was underrepresented for providing sufficient insight into the species' genetic structure there.…”

Phylogenetic analysis of Brachymystax and Hucho genera—Summary on evolutionary status within the Salmoninae subfamily

“…However, some of analyzed in this study haplotypes that were previously assigned to Clade A (haplo2 and 3) displayed closer relationship to haplotype classified to Clade B (haplo1). The exceptionally low frequencies of German specific haplotypes and prevalence of haplotypes specific for Clade B reported by Kucinski et al (2015) may be sign of historical introgression between mentioned clades.…”

“…The performed molecular dating evidenced that the observed split between both lineages most likely occurred before the last glaciation (150,000-200,000 years ago), where each of them may represent previously hypothesized different glacial refugia-associated lineages, i.e., North/North-Eastern (Gum et al, 2005;Panin et al, 2020). The available phylogeographic data display similar pattern of two distinct phylogenetic clusters across Europe, namely: Clade A (Austria, Slovenia and Germany) and Clade B (Poland, Slovakia, Ukraine, Bosnia-Herzegovina, Montenegro, and Serbia) (Kucinski et al, 2015;Maric, Razpet, et al, 2014;Weiss et al, 2011). However, some of analyzed in this study haplotypes that were previously assigned to Clade A (haplo2 and 3) displayed The genus Parahucho is known as unique monotypic lineage, which is exclusively represented by one anadromous species, i.e., P. perryi.…”

“…The phylogenetic analyses were based on mitochondrial and nuclear genetic data retrieved from NCBI. To construct a supermatrix, the data previously deposited by Kucinski et al (2015) (KM593284‐KM593293) was used as reference. The search for homologous DNA clusters was performed by application of Genome Workbench software (version 3.6.0) (Kuznetsov & Bollin, 2021).…”