Numbers peak in late summer so everbearer varieties are particularly badly affected - the nymphs and adults of ETPB forage on developing flowers, causing fruit to malform.
More than 50 per cent of fruit can be downgraded as a result of capsid feeding in unsprayed crops. Currently, no bio-control measures are commercially available so growers are reliant on insecticides. HDC project SF 95 was commissioned to screen a range of insecticides against different life stages of the pest and determine the optimal application timing.
Strawberry growers have relied heavily on Brigade (bifenthrin), which is effective. But as a synthetic pyrethroid, it is incompatible with the IPM programmes needed to control other common everbearer pests. It is also harmful to bees so should not be applied freely during flowering, making it difficult to use on everbearers.
In the first year of trials in 2008, Brigade and Hallmark (lambda-cyhalothrin) were the most effective. The experiments had been timed to target different life stages of the capsid but the products tested appeared equally effective against all stages. In 2009, the most effective treatments were applied to everbearers in late July when pest populations were present.
Only Brigade significantly reduced the percentage of capsid-damaged fruits. In terms of pest control, Brigade was outstanding, reducing numbers to close to zero. With only one treatment, ETPB numbers were still significantly lower than any other treatment 23 days after application. Use of Brigade should be avoided where IPM is being used.
Horticultural Development Company
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