Resistance to genetic insect control: Modelling the effects of space.
Genetic insect control, such as self-limiting RIDL2(Release of Insects Carrying a Dominant Lethal) technology, is a development of the sterile insect technique which is proposed to suppress wild populations of a number of major agricultural and public health insect pests. This is achieved by mass rearing and releasing male insects that are homozygous for a repressible dominant lethal genetic construct, which causes death in progeny when inherited. The released genetically engineered ('GE') insects compete for mates with wild individuals, resulting in population suppression. A previous study modelled the evolution of a hypothetical resistance to the lethal construct using a frequency-dependent population genetic and population dynamic approach. This found that proliferation of resistance is possible but can be diluted by the introgression of susceptible alleles from the released homozygous-susceptible GE males. We develop this approach within a spatial context by modelling the spread of a lethal construct and resistance trait, and the effect on population control, in a two deme metapopulation, with GE release in one deme. Results show that spatial effects can drive an increased or decreased evolution of resistance in both the target and non-target demes, depending on the effectiveness and associated costs of the resistant trait, and on the rate of dispersal. A recurrent theme is the potential for the non-target deme to act as a source of resistant or susceptible alleles for the target deme through dispersal. This can in turn have a major impact on the effectiveness of insect population control.
Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire SL5 7PY, United Kingdom. Electronic address: bmw45@cam.ac.uk.
Benjamin
B
Watkinson-Powell
Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire SL5 7PY, United Kingdom; Mathematical Ecology Research Group, Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, United Kingdom. Electronic address: nina.alphey@zoo.ox.ac.uk.
Nina
N
Alphey
D000818:Animals; D005787:Gene Frequency / Q000235:genetics; D005799:Genes, Dominant; D007300:Insect Control; D007313:Insecta; D008962:Models, Theoretical; D010572:Pest Control, Biological; D011157:Population Dynamics
Mathematical modelling; Pest insects; Self-limiting RIDL; Spatial dynamics; Sterile insect technique (SIT)