Spotted wing drosophila fly threat on fruit farms

Fruit growers have been urged by Teagasc to monitor for the presence of the spotted wing drosophila (SWD) fly.
Spotted wing drosophila fly threat on fruit farms

Its presence in Ireland was confirmed for the first time last June, at commercial fruit growing farms in Dublin and Wexford.

Recognised as a pest in Europe since 2008, it damages fruit and can allow secondary pathogens to infest fruit.

It was blamed for losses of up to 80% in some strawberry crops in southern France in 2010.

More recent evidence from Holland and England indicated that losses of 30% plus.

According to Teagasc, it is clear that the cost of treating for SWD is far less than the potential yield loss.

Potential losses of 50% are reported for raspberry and other cane fruit, 33% for sweet cherry, and 25% for blueberry.

Also susceptible are blueberries, tomatoes, plums, apples, raspberries, pears, currants, blackberry and honeysuckle.

Eradication is not considered feasible.

In addition to direct yield loss, five to 14 extra applications of insecticides are needed to control SWD, and there is extra labour for monitoring for damage in harvested crops and extra labour costs in disposing of infested fruit.

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