Aphidalia
General
Acyrthosiphon malvae rogersii is a pest of strawberry that is widely distributed in northern and western Europe.
Life cycle and appearance of Acyrthosiphon malvae rogersii
Aphids have a complex life cycle, with both winged and wingless forms of adults and a great variety in colour. In greenhouses, reproduction 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.
Acyrthosiphon malvae rogersii is holocyclic (i.e. they mate in autumn and produce eggs to overwinter) and monoecious (i.e. they do not change their host plant for overwintering).
Wingless females are green or yellow green, often shiny with pale siphunculi and 1.5-2.7 mm long.
Damage symptoms
Wingless aphids may form large colonies on young strawberry foliage, particularly along the petioles. In outdoor strawberries they reach their peak in June. Winged aphids are formed from May onwards and are responsible for spreading the infestation to other strawberry plants. Acyrthosiphon malvae rogersii can spread strawberry mottle virus.
