Shift in Phenotypic Variation Coupled With Rapid Loss of Genetic Diversity in Captive Populations of <I>Eristalis tenax</I> (Diptera: Syrphidae): Consequences for Rearing and Potential Commercial Use

Abstract

Because of its importance as a pollinator and its potential economic usefulness for the biodegradation of organic animal waste, the genetic and phenotypic diversity of the drone fly, Eristalis tenax L. (Diptera: Syrphidae), was studied in both wild and captive populations from southeastern Europe. Wild specimens from a natural protected habitat (with low human impact), field crop habitat (semisynanthropic condition), and intensive pig farming habitat (synanthropic condition) were compared with a laboratory colony reared on artificial media An integrative approach was applied based on allozyme loci, cytochrome c oxidase I mitochondrial DNA, wing traits (size and shape), and abdominal color patterns. Our results indicate that the fourth and eighth generations of the laboratory colony show a severe lack of genetic diversity compared with natural populations. Reduced genetic diversity in subsequent generations (F4 and F8) of the laboratory colony was found to be linked with phenotypic divergence. Loss of genetic variability associated with phenotypic differentiation in laboratory samples suggests a founder effect, followed by stochastic genetic processes and inbreeding. Hence, our results have implications for captive bred Eristalis flies, which have been used in crop pollination and biodegradation of organic waste under synanthropic conditions.

Phylogeographic patterns of Merodon hoverflies in the Eastern Mediterranean region: revealing connections and barriers

“…; Francuski et al. ; Haarto and Ståhls ). To further assess the presence of genetic polymorphism within the study taxa, the entire nuclear genome was screened using Inter‐Simple Sequence Repeats (ISSR) with a tetra‐nucleotide primer, (GACA) 4, and converted into a genomic fingerprint.…”

“…Altogether, a few cases of inconsistency between morphological and molecular hypothesis have been observed among Syrphidae taxa in studies concerning very closely related taxa. Introgression among closely related taxa or incomplete lineage sorting resulting in haplotype sharing being hypothesized as likely causes in these studies (e.g., Milankov et al 2009Milankov et al , 2013St ahls et al 2009;Francuski et al 2014;Haarto and St ahls 2014). To further assess the presence of genetic polymorphism within the study taxa, the entire nuclear genome was screened using Inter-Simple Sequence Repeats (ISSR) with a tetra-nucleotide primer, (GACA) 4, and converted into a genomic fingerprint.…”

Assessing spatial population structure and heterogeneity in the dronefly

“…We obtained individual genotypes from subsets of individuals used in previous studies: Francuski et al . (2011; 2013 a,b ; 2014 a,b ). Sample sizes in populations ranged from 11 to 122 individuals while distance between sampling sites ranged from 17 to 3322 km.…”

Effect of mass rearing on the genetic diversity of the predatory mite Amblyseius swirskii

“…Also, inbred populations of the mass-reared parasitoid Trichogramma pretiosum (Riley) produced fewer offspring than genetically variable populations (Guzm an-Larralde et al, 2014). A severe lack of genetic diversity and phenotypic differentiation in wing size and abdomen colour were found for one inbred laboratory colony of the crop pollinator Eristalis tenax (L.) compared with natural populations (Francuski et al, 2014). In another case, reproduction parameters and virulence of the entomopathogenic nematode Steinernema glaseri (Steiner) were reduced after laboratory adaptation took place (Stuart & Gaugler, 1996).…”