Progressing fleabane weed biocontrol solutions for the Australian grains industry

Fleabanes (including flaxleaf and tall fleabane) are amongst the most damaging crop weeds in Australia, resulting in reduced crop production and increased chemical herbicide costs. The rapid spread of some herbicide resistant populations of fleabane is making it increasingly difficult for growers to manage these weeds, especially in summer fallow. Through recent investment by GRDC and AgriFutures Australia, strong advances have been made by the CSIRO in progressing potential biocontrol solutions for managing grain cropping weeds. Firstly, the flaxleaf fleabane rust fungus is in the early stages of release. However, this process needs to be optimised to improve infection rates in the field and monitored to determine how it will be impacted by normal cropping practices. Such optimisation must be achieved prior to a nationwide launch of the fungus with growers and other key stakeholders across the grains sector. Secondly, several candidate insect biocontrol agents that attack multiple fleabane species have been identified to progress to the host-specificity testing stage for biocontrol risk assessment. This project will seek to test the safety of these insects on native and other important plant species in Australia, with the aim of applying to federal regulators for permission to release those insects into the Australian environment to help control the target weeds.