The Foxglove Aphid (Aulacorthum solani) is a pest of multiple agricultural crops including, tomatoes, cucumbers, and peppers. They are also sometimes found on lettuce.
Life cycle and appearance
Aphids have a complex life cycle, with both winged and wingless forms of adults and a great variety in colour. When reproduction is asexual, the young aphids are born as developed nymphs. They immediately start to feed on plant sap and grow rapidly. When reproduction is sexual, the aphids lay eggs that overwinter. In greenhouses reproduction also takes place by parthenogenesis, with unfertilized viviparous females continuing to produce new generations of females. Aphids moult four times before reaching adulthood. With each moult they shed white skin, betraying their presence in the crop.
Foxglove Aphids have multiple color forms, anywhere from green to orange to pink with dark spots at the base of the cornicles. Winged adults are browner in color than the wingless forms, and also have various black markings. An easier way to know if you’re dealing with this aphid is the black banding on their legs and antenna, this is not present with many other common greenhouse aphids.
The Foxglove Aphid will pierce the leaves or the fruit of the crop in question for a food source. Plant sap is rich in sugars, but has a low protein content. Aphids therefore need to extract large quantities of sap to get sufficient protein. The excess sugar is secreted in the form of honeydew, making the crop and its fruit sticky. Black fungal moulds (Cladosporium spp.) grow on this honeydew, contaminating fruit and ornamental crops and rendering them unsuitable for market. At the same time, photosynthesis in the leaves is reduced, affecting production. It is also known to transmit the lettuce Mosaic Virus.
How to get rid of Foxglove Aphid
Koppert offers different solutions for biological pest control of Foxglove Aphid.