Redcurrant blister aphid

The Redcurrant blister aphid (scientifically known as Cryptomyzus ribis) is a significant pest belonging to the order Hemiptera and the family Aphididae. It is a highly specialized insect that targets specific species of Ribes bushes as its primary host plants.

This pest is primarily found on red and white currants, although it can occasionally infest black currants and gooseberries. The aphids settle on the underside of young leaves, making them difficult to spot during the initial stages of colonization until the plant starts showing visible symptoms.

The life cycle begins with overwintering eggs located near the buds of host plants. When the buds break in spring, the eggs hatch into fundatrices (stem mothers). During the summer, the population grows rapidly through asexual reproduction, leading to the appearance of winged migrants, while sexual forms emerge in autumn to lay overwintering eggs.

Damage is characterized by the formation of blister-like galls on the upper surface of leaves. These blisters are usually red, yellow, or pale green. The feeding activity disrupts the plant's photosynthetic process, causing severe leaf curling, premature yellowing, and eventual leaf drop, which weakens the host plant.

Control strategies involve both cultural and chemical methods. Early monitoring is crucial, as the first signs of damage appear as the leaves expand. Chemical intervention with systemic or contact insecticides is most effective just before flowering or immediately after the harvest season to prevent population explosions.

• Pruning and destroying heavily infested shoot tips.
• Encouraging natural predators like ladybirds and hoverfly larvae.
• Applying insecticides before the curling of leaves makes the pest unreachable.
• Maintaining vigorous plant health through adequate nutrition and irrigation.