Keeping spider mites at bay in aubergines

1/03/2021 - Spring is the time when spider mites often appear in aubergine crops. To keep this pest effectively controlled, we recommend using a combination of the predatory mite Phytoseiulus-System together with the gall midge - Feltiella-System. Highly mobile, this gall midge plays a valuable role by actively seeking out pest hotspots throughout the entire crop.

“Most aubergine growers will have already introduced predatory mites into their crops to target thrips – utilising products like Montdorensis-System or Swirskii-System,” explains Biobest adviser Stefan Bohte. “As soon as growers detect spider mites in the crop, they should start introducing Phytoseiulus-System and Feltiella-System.”

“The predatory mite Phytoseiulus persimilis gets to work immediately feeding on the two-spotted spider mites. However, keep in mind that a strong swirskii population can hinder Phytoseiulus population development - as it can feed on the eggs; this is less of an issue with Transeius montdorensis.”

Gall midge seeks out hotspots

“Growers combining Phytoseiulus-System with Feltiella-System are in a stronger position to effectively control spider mites,” says Stefan.

"The gall midge, Feltiella acarisuga, flies around the greenhouse looking for spider mites. Capable of locating pest hotspots hundreds of metres apart, it lays its eggs in these hotspots. As soon as the eggs hatch, each voracious larva can eat up to 30 spider mites in various stages of development.”

Consult on additional agents

In situations where the two-spotted spider mite is still not adequately controlled, there is the option to apply a chemical or biological agent; however, Stefan stresses this is not necessary if the head of the aubergine plant is still green. “We advise growers to consult their Biobest advisor before applying any pesticide - to check compatibility with the biological controls at work in the crop,” he says. “Growers can also check our side effects list on our website."