Genetic composition of a population of natural common bream Abramis brama × roach Rutilus rutilus hybrids and their morphological characteristics in comparison with parent species

Abstract

Common bream Abramis brama, roach Rutilus rutilus and their hybrids were collected in the Dobczyce Reservoir in southern Poland in 2006-2013 to study whether it is better for a hybrid individual to resemble and compete with one of its parents, or to minimize competition by having a distinctive phenotype. All hybrids were F crosses and originated predominantly (93·2%) from matings between female A. brama and male R. rutilus parents. In morphometric analyses, a newly defined coefficient, L = 2·5 (body mass) (L × body depth) , which enables forms with similar length-depth proportions but different length-mass relationships to be distinguished was used. Morphometric and meristic characteristics of the hybrids were intermediate in comparison with the parental species, with small but significant deviation towards R. rutilus in longitudinal body dimensions (trunk and tail length) and towards A. brama in body cross-sectional shape (body depth and L coefficient). This may result in a more R. rutilus like propulsion in hybrids and a more A. brama like ability to manoeuvre.

Molecular Structure and Hybridization Patterns of Abramis brama × Rutilus rutilus Hybrids from Modrac Reservoir, Bosnia and Herzegovina

“…Analysis of the mitochondrial cytb region revealed that hybrids in Modrac Reservoir originate predominantly from the mating between bream females and roach males. This is in agreement with previous studies (Wyatt et al, 2006;Hayden et al, 2010;Kuparinen et al, 2014;Konopiński and Amirowicz, 2017) and appears to be a universal direction of hybridization of these two species, across their overlapping range in Europe. When all markers and analyses were concerned, 16 specimens appeared as undoubted hybrid individuals.…”

“…Although it could be argued that the number of employed microsatellite markers was low, private alleles were observed for all five loci used in calculations (Table 1), proving their informativeness for the delineation of parental species and hybrid individuals. The mean gene diversity for hybrids was high (0.884) in our study, as it was in Konopiński and Amirowicz (2017), in which the mean genetic diversity in hybrids (0.716) was slightly lower than in R. rutilus (0.731), but higher than in A. brama (0.370). For the chosen microsatellite set, hybrids from our survey displayed higher gene diversity than both parent species (Table 2).…”

“…However, the crossing of bream and roach (female first) was successful under controlled conditions in a study by Matondo et al (2008). Though the possibility of backcross of F 1 -hybrids with either parental species has been demonstrated under controlled conditions (Pitts et al, 1997), the frequency of occurrence of F 2 -hybrids in nature is low (Wyatt et al, 2006;Hayden et al, 2010;Kuparinen et al, 2014, Konopiński andAmirowicz, 2017). The variation in observable morphometric and meristic characteristics in the hybrid offspring is likely increased by backcrossing, aggravating the identification problems (Wood and Jordan, 1987).…”

Vigour‐related traits and immunity in hybrids of evolutionary divergent cyprinoid species: advantages of hybrid heterosis?

“…Hybridization is associated with a strong bias in mating preference; i.e ., it was shown that F1 hybrids originated from the mating of common bream females with roach males (Hayden et al ., 2010; Konopiński & Amirowicz, 2018; Kuparinen et al ., 2014), whereas a similar proportion of F1 hybrids with a different maternal parent (common bream or roach) was reported in some regions (Krasnovyd et al ., 2017). Hybrids of roach and common bream express an intermediate morphological phenotype (Hayden et al ., 2010; Konopiński & Amirowicz, 2018), display an intermediate niche breadth and trophic position and use a broader range of trophic resources compared with parental species (Hayden et al ., 2011; Toscano et al ., 2010; Wood & Jordan, 1987). A wider food spectrum and less sensitivity to fluctuations in the availability of particular foods facilitate rapid growth in hybrids (Hayden et al ., 2014).…”

Genetic Differentiation of Ukrainian Populations of Eusomus ovulum (Coleoptera, Curculionidae): Evidence of Multiple Hybrid Speciation

“…Hybrids are oft en sterile (Feng et al, 2020). Numerous fertile hybrids can be an important component of the populations of parental species (Konopiński, Amirowicz, 2018.). Finally, hybridization generates sometimes a new genetic form that diff ers from both parental species and is capable to reproduce autonomically (hybrid speciation) (Mallet, 2007;Vallejo-Marín, Hiscock, 2016).…”