Author
Sonja Stutz
s.stutz@cabi.org
CABI
Delémont
Coauthors
Cornelia Cloşca, CABI, Delémont, Switzerland
Ghislaine Cortat, CABI, Delémont, Switzerland
Patrick Häfliger, CABI, Delémont, Switzerland
Hariet L Hinz , CABI, Delémont, Switzerland
Lauréline Humair, CABI, Delémont, Switzerland
Urs Schaffner, CABI, Delémont, Switzerland
Philip Weyl, CABI, Delémont, Switzerland
Abstract
It has been widely accepted that open-field host specificity tests are the most reliable method to determine the ecological host range of potential biological control agents. This is largely linked to the more natural setting of open-field tests when compared to tests conducted in cages. However, even open-field tests may over- or underestimate the likelihood of an agent utilizing non-target species after its introduction into a new range.
We will present the methods, results and interpretation of open-field tests that we conducted with a wide range of potential biological control agents from several insect orders using different designs. More specifically, we will explore how factors such as the spatial distribution of target and non-target plants (e.g. distance from the release point and/or the closest host plant), the habitat in which the test is set up, the biology and mobility of the agents as well as the phenology of the exposed plants may influence the results of open-field tests. The advantages and limitations of the different open-field designs will be explored and the conclusions that can be drawn from them will be discussed.
keywords
open-field test
host-specificity testing
design
agent biology
Highlights
Biology and habitat preference of agent need to be considered when conducting open-field tests
Open-field tests provide information on host-specificity, but also on e.g., dispersal behaviour
Careful selection and use of various open-field designs facilitate interpretation of results