Description, Biology, Life Cycle, Damage, Common Names, Images
- Host plants: plum, apple, peach (nectarine).
- Adult: emerging from hibernation in bark crevices or in other sheltered places, adults resume activity and then destroy numerous buds by forming lateral incision. They eventually attack the young leaves, shoots, flowers and even the fruitlets (*) .
Mating and egg laying occur after 3 to 4 weeks. The female lays eggs in the shoots and eventually in the fruitlets (*) : it forms two galleries, one receiving the egg, the second incising the woody fibres of the peduncle.
Average fecundity, 100 to 150 eggs.
- Egg: development lasts 5 to 9 days.
- Larva: it devours the pulp of the fruit (*) by digging large flat galleries then, after 1 month, vacates the fruit and drops to the ground where it remains in diapause in a small earthen cell for 13 to 14 months.
- Pupation occurs in the middle of the next summer; the adult feeds on the leaves and buds then enters winter shelter.
The complete cycle occurs over 2 years and the insects overwinter in the larval then the adult stages; the eggs laid in May produce larvae which feed then bury themselves in the ground untill pupating in the next summer. The adults emerging in September feed then overwinter and breed only during the next spring.
Adults are harmful at the beginning of feeding, when they destroy the buds.
In addition, the bites allow a fungus (Sclerotinia fructigena) to develop.
- The larva devours a very large number of fruitlets.
HYPPZ on line : Species (scientific name), Pests (common names), Glossary, Crops.