Are commercial stocks of biological control agents genetically depauperate? – A case study on the pirate bug Orius majusculus Reuter

Publication date: Available online 23 August 2018Source: Biological ControlAuthor(s): Louise B. Rasmussen, Kim Jensen, Jesper G. Sørensen, Elsa Sverrisdóttir, Kåre L. Nielsen, Johannes Overgaard, Martin Holmstrup, Torsten N. KristensenAbstractPredatory arthropods are increasingly used in biological control of insect pests. For this purpose, control agents are produced commercially in large quantities for release in crops. The production stocks, however, may have undergone numerous population bottlenecks and may have been exposed to artificial selection pressures in the production facilities. Accordingly, commercial populations may be experiencing loss of genetic variation through inbreeding and genetic drift, which may reduce fitness and biocontrol efficiency. In the present study we investigated whether populations of the pirate bug Orius majusculus (Reuter) purchased from three European companies differed in a range of performance traits including predation rate, starvation tolerance, body size, locomotor activity, and heat tolerance. Furthermore, we crossed all populations pairwise and tested whether outcrossed F2 hybrid offspring had increased performance compared to the parental populations, as would be expected if they were genetically distinct and depauperate. Transcriptome sequencing (RNA-seq) revealed similar overall levels of genetic variation among commercial populations, but also evidence for genetic differentiation. Generally, females performed better across p...

Source: Biological Control - August 23, 2018 Category: Biology Source Type: research