DOI: 10.5061/dryad.5cm7088
title: Data from: The application of self-limiting transgenic insects in managing resistance in experimental metapopulations

description: 1. The mass release of transgenic insects carrying female lethal
 self-limiting genes can reduce pest insect populations. Theoretically,
 substantial releases can be a novel resistance management tool, since wild
 type alleles conferring susceptibility to pesticides can dilute resistance
 alleles in target populations. A potential barrier to the deployment of
 this technology is the need for large-scale area wide releases. Here we
 address whether localized releases of transgenic insects could provide an
 alternative, means of population suppression and resistance management,
 without serious loss of efficacy. 2. We used experimental mesocosms
 constituting insect metapopulations to explore the evolution of resistance
 to the Bacillus thuringiensis toxin Cry1Ac in a high-dose/refugia
 landscape in the insect Plutella xylostella. We ran two selection
 experiments, the first compared the efficacy of ‘everywhere’ releases and
 negative controls to a spatially density-dependent or ‘whack-a-mole’
 strategy that concentrated release of transgenic insects in
 sub-populations with high levels of resistance. The second experiment
 tested the relative efficacy of whack-a-mole and everywhere releases under
 spatially homogenous and heterogeneous selection pressure. 3. The
 whack-a-mole releases were less effective than everywhere releases in
 terms of slowing the evolution of resistance, which in the first
 experiment, largely prevented the evolution of resistance. In contrast to
 predictions, heterogeneous whack-a-mole releases were not more effective
 under heterogeneous selection pressure. Heterogeneous selection pressure
 did, however, reduce total insect population sizes 4. Whack-a-mole
 releases provided early population suppression that was indistinguishable
 from homogeneous everywhere releases. However, insect population densities
 tracked the evolution of resistance in this system, as phenotypic
 resistance provides access to the 90% of experimental diet containing the
 toxin Cry1Ac. Thus, as resistance levels diverged between treatments,
 carrying capacities diverged and population sizes increased under the
 whack- a-mole approach. Synthesis and Applications Spatially
 density-dependent releases of transgenic insects, particularly those
 targeting source populations at landscape level, could suppress pest
 populations in the absence of blanket area-wide management. The resistance
 management benefits of self-limiting transgenic insects are, however,
 reduced in spatially localized releases, suggesting that they are not best
 suited for spatially restricted ‘spot’ treatment of problematic
 resistance. Nevertheless, area-wide and spatially heterogeneous releases
 could be used to support other resistance management interventions.
description: Raw comma separated data
 for experimentpopulation size and
 bioassay data for experimental mesocosms. See readme file for more details
 on column heading and example analysis code.experiment1.csvRaw data for experiment 2population size and bioassay data for experimental mesocosms. See readme file for more details on column headings and example analysis codeexperiment2.csv