This is a final research report from Hort Innovation’s historical archives. Please note that as these reports may date back as far as the 1990s, the content and recommendations within them may be superseded by more recent research.

What was it all about?

At the commencement of this project the Victorian strawberry industry was facing a crisis in the form of insecticide resistant insects and mites. In particular, western flower thrips (WFT) and two-spotted mite (TSM) were causing significant problems as growers tried to deal with them using a pesticide-based approach. These pests were threatening the viability of individual farms and also the Victorian strawberry industry.

This project developed an alternative method of controlling these key pests, and also all other pests, for those growers who want to use it. An Integrated Pest Management (IPM) strategy had been developed that had biological and cultural controls as the basis for managing pests, with insecticides or miticides used only as support tools (not as the primary control).

The biological control agents used in the strategy included both naturally occurring and commercially produced predatory insects and mites. The commercially produced species included the predatory mites Persimilis, Hypoaspis and Cucumeris. Naturally occurring species included predatory thrips (Haplothrips), brown lacewings, damsel bugs, hoverflies and predatory mites.

Cultural control methods may have included removal of heavily infested leaf material, weed management, grass inter-rows, the use of covers or not, and plant canopy management.

Chemical control options within the strategy relied on minimal pesticide use and the use of selective or low-residual products where available. Reports from local resellers were that sales of Lannate® and dimethoate (previously the mainstays of crop protection in the industry) were down by 80% since the commencement of this project.

Many Victorian strawberry growers were now successfully using the IPM strategy (as outlined in Appendix 1 of this report). Adoption of this strategy was extremely high, in terms of the percentage of strawberry production now using IPM, and rapid compared to most IPM projects (worldwide). Hort Innovation (which was then Horticulture Australia Limited) estimated that over 50% of Victorian production was now achieved using IPM.