Monday, December 10, 2007 - 8:53 AM

Managing resistance to Bt crops by mass-release of engineered insects

Nina Alphey,, University of Oxford (also Oxitec Limited), Mathematical Ecology Research Group, Department of Zoology, Tinbergen Building, South Parks Road, Oxford, United Kingdom, Paul G. Coleman,, London School of Hygiene & Tropical Medicine (& formerly Oxitec Limited), Department of Infectious & Tropical Diseases, Keppel Street, London, United Kingdom, Christl. A. Donnelly,, Imperial College London, Department of Infectious Disease Epidemiology, Faculty of Medicine, Norfolk Place, London, United Kingdom, and Luke Alphey,, Oxitec Limited (also University of Oxford ), 71 Milton Park, Oxford, United Kingdom.

Transgenic crops producing insecticidal toxins are now widely used to control insect pests. The benefits of this method would be lost if resistance to the toxins spread to a significant proportion of the pest population. The primary resistance management method, mandatory in some countries including the USA, is the high-dose / refuge strategy, requiring toxin-free crops as refuges near the insecticidal crops, and the use of toxin doses sufficiently high to kill insects heterozygous for a resistance allele, thereby rendering the resistance functionally recessive. We propose that mass-release of harmless susceptible (toxin-sensitive) insects could substantially delay or even reverse the spread of resistance. Mass-release of such insects is an integral part of RIDL, a method of pest control related to the Sterile Insect Technique (SIT) using proprietary technology originally developed at the University of Oxford. We show by mathematical modeling that specific RIDL strategies could form an effective component of a resistance management strategy for plant-incorporated protectants and other toxins.

Journal of Economic Entomology 100(5):1642-1649 (2007)