We all want to know what the future holds, but when it comes to resistance, being able to predict the drivers of future resistance evolution can be critical to improved management practices.
As part of the Australian Grains Pest Innovation Program (AGPIP), our researchers are investigating the factors that accelerate or delay resistance evolution in insect grain pests.
Insecticide resistance story in Australia
So far, several key grain pests such as the green peach aphid (Myzus persicae), redlegged earth mite (Halotydeus destructor), diamondback moth (Plutella xylostella) and cotton bollworm (Helicoverpa armigera) have already evolved resistance to registered insecticide options.
Additionally, predictive modelling work undertaken by cesar in 2019, as part of a GRDC-funded IPM project led by the Birchip Cropping Group, identified a number of grain pests with a higher risk of evolving resistance in the future.
Exploring drivers of insecticide resistance evolution
cesar’s Senior Research Scientist, Dr James Maino, is leading AGPIP research to extend these findings by developing more accurate predictions of resistance risks to support improved resistance management practices.
The evolution of resistance in pest populations reduces the options available for managing potential outbreaks and can increase selection pressures for remaining chemical actives.
Selection pressures (i.e. pesticide exposure) might be a main driver of resistance evolution, but we currently lack reliable methods to estimate selection pressures for grains pests.
Additionally, there are a number of other factors that may impact the evolution of insecticide resistance including the local environment, species biology and their ecology.
Developing an early warning system
James is working with other AGPIP team members to mine resistance databases and identify cases of resistance both globally and in Australia. This data will then be used to map resistance occurrences and track global resistance trends, as well as inform our understanding of resistance mechanisms and other potential drivers of resistance evolution for key grain pests in Australia.
Long-term the research will support the development of an early warning system that can identify resistance risks for grain pests before the resistance evolves or becomes widespread in Australia.
Ultimately, this will help us better predict when, where, and how resistance might occur, and help direct the development of resistance management strategies!
This research is being undertaken as part of the Australian Grains Pest Innovation Program (AGPIP). AGPIP is a collaboration between the Pest & Environmental Adaptation Research Group at the University of Melbourne and cesar. The program is a co-investment by the Grains Research and Development Corporation (GRDC) and the University of Melbourne, together with in-kind contributions from all program partners.