This project will use individual-based modelling to investigate how genetic, biological, ecological and management factors interact to affect the evolution of resistance to the grain fumigant phosphine in the stored-grain pest, the lesser grain borer. This information will help identify optimal management strategies for delaying or avoiding the evolution of resistance.

What is the biosecurity problem?

The evolution of resistance to phosphine in the lesser grain borer.

The main output of this project is to:

• create simulation and statistical models of the population dynamics of Rhyzopertha dominica (lesser grain borer) that will incorporate evolution of resistance to phosphine. These models will be used to evaluate monitoring strategies and management programs to avoid, delay or minimise the evolution of resistance.

Who will be the end-users of this research?

Scientific researchers and agriculture biosecurity policy makers. Public and private extension officers, agronomists and farmers will be indirect end-users through resulting recommendations.

This project will provide a mathematical framework from which future management strategies on phosphine fumigation of Rhyzopertha dominica can be derived, with consideration of the species' increasing genetic resistance to phosphine.

What is the biosecurity problem?

Phosphine resistance of Rhyzopertha dominica
(Coleoptera: Bostrichidae).

The outputs of this project are to:

• develop an understanding of the significance of the differences between resistance occurring on one gene compared to two genes for the emergence of resistance

• develop a preliminary software tool for assessing different fumigation strategies, and

• train an honours student in insecticide resistance modelling in the postharvest system, with the view to developing the skills necessary to do a PhD in this area.

Who will be the end-user of this research?

Bulk handlers are the major end uses of the project, although any stakeholder that stores grain will benefit from the research developed in the project. Stored product researches will also benefit from insights delivered by the project.