1 wasp / mummy / 2 m2 per week. Increase to 5 / m2 for 3 weeks if small aphid colonies are present.
Most crops can be infested with aphids. Damage is caused in three ways: sucking plant sap when feeding, excretion of honeydew leading to sooty mould and some species can transmit plant viruses leading to distortion and disfigured plant growth. Biological control with parasites, predators and fungal pathogens are available depending on crop and environmental conditions. There are a large number of aphid species and identification can be important when parasitic wasps are to be used. Depending on the species there can be alternate plant hosts. Winged forms develop under conditions of high density to migrate to alternate hosts. Resistance to some insecticides is a serious issue with some species.
Activity / Control
Aphidius ervi is specifically for the larger elliptical shaped species including Macrosiphum euphorbiae (potato aphid) and Aulacorthum solani (glasshouse potato aphid). Several other aphid species such as the pea aphid are also parasitised. The adult wasp inserts its egg into the aphid, a parasite larva develops killing the aphid, producing a characteristic goldenbrown papery 'mummy' with Aphidius and Praon species. An adult parasitic wasp later emerges through a round hole on the mummified aphid. The adult wasps also feed as a predator on aphids, killing one or more each day.
Use at the first sign of aphids or better, as an early season preventative.
Aphidius ervi is specifically for the larger elliptical shaped species including Macrosiphum euphorbiae (potato aphid), and Aulacorthum solani (glasshouse potato aphid). Several other aphid species such as the pea aphid are also parasitised.
A strong flier, it can locate small aphid colonies, making it excellent for preventive applications. Capable of parasitising hundreds of aphids.