TECHNICAL
STRAWBERRY GROWERS TAKE STRIDES TOWARDS INTEGRATED PEST MANAGEMENT, WITH NEW RESEARCH SHOWING PROMISE Words by Hugh Chesterman : Communications and Events Assistant, HortNZ
Early findings from a three-year research project into thrips management are already yielding promising results, and sparking conversations about how Integrated Pest Management, or IPM, can be adopted by the industry. More than 50 strawberry growers, consultants, and industry specialists attended a field day on 14 January to see field trials at Anthony Rakich’s Danube Orchards. The field day marked a key milestone of the Sustainable Farming Fund research project which seeks to find new ways to treat thrips using an IPM based approach. At Anthony’s family property, Plant & Food Research are testing, in consultation with Dr Paul Horne (IPM Technologies Pty Ltd, Australia) and Chris Thomson (Bioforce Ltd), a range of IPM strategies as part of the “Future-proofing thrips management in strawberries” research project.
If we’re able to have less pests and use less spray, we’ll have a better product. That would be a win-win for everyone “The results have been really exciting,” said Anthony. “Thrips numbers are already starting to come down, and I’ve been finding predators that have been released spreading to other blocks. It’s really cool to see. “We’ve learnt a lot from the trials already. We missed an opportunity to spray early on which could have helped the establishment of predators, but it’s all part of building information that growers can use about what to do and when to do it. “I’m really optimistic about what IPM can offer. I want to be able to have a programme that doesn’t rely on sprays, especially with resistance increasing. I think it would be
great for the industry if we’re able to embrace it early while we still have an arsenal of working soft chemistries. “As an industry, we want people to buy strawberries. If we’re able to have less pests and use less spray, we’ll have a better product. That would be a win-win for everyone.” To understand what species of thrips, other pests, and their natural enemies are present on strawberry crops, the first year of the project sought to identify bugs present in crops and review what has worked overseas in treating pests. “A cornerstone of the trials, and any IPM strategy, has been monitoring the numbers of pest species and their naturally occurring predators,” said Dr Mette Nielsen, Entomologist at Plant & Food Research. “By monitoring levels in our test block against Anthony’s control block, we’re able to test the effectiveness of various IPM interventions. Blue sticky traps and the release of commercially available predatory mite controls such as Cucumeris, Hypoaspis and Persimilis have already been successfully deployed in Danube Orchards this season. “Cucumeris mite has proved to be a promising beneficial (predatory insect) that is already on the market. It feeds on the early larval stages of thrips, disrupting their lifecycle. They also can feed on other pests such as the ‘two spotted spider mites’. “We’re also looking at what pesticide products most accurately target pests. By combining field monitoring with spray diaries, we’re able to get a good picture of which sprays are most effective and don’t disrupt beneficials.” NZGROWER : FEBRUARY 2021
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