Sterile Insect Technique (SIT) for vector and pest control: the partial sterile case and nonlinear control strategies for release

International audienceThe Sterile Insect Technique (SIT) is a biological control method that consists of releasing males thathave been sterilized using ionizing radiation; these males will mate with wild females that will not produceviable offsprings.In this talk we present a minimalist model for SIT, assuming that residual fertility can occur in the sterilemale population after radiation. Taking into account that we are able to get regular measurements fromthe biological system along the control duration, such as the size of the wild insect population, we studydifferent control strategies that involve either continuous or periodic impulsive releases. We show that acombination of open-loop control with constant large releases and closed-loop nonlinear control leads tothe best strategy in terms of both number of releases and total quantity of sterile males to be released.Additionally, we show that SIT fails if the residual fertility is greater than a threshold value that dependson the wild population biological parameters. Moreover, even for small values, the residual fertility inducesthe use of such large releases, that SIT alone is not always reasonable from a practical point of view. Weprovide applications against a mosquito species, Aedes albopictus, and a fruit fly, Bactrocera dorsalis