Pear psylla is an increasing problem. The extensive presence of this parasite can cause considerable economic damage. As the larvae transform (L1 to L5) the amount of honeydew secreted also increases. This honeydew is a major cause of fungus formation. In addition to damage to the flowers and leaves, the fruit is also damaged by this parasite. The pear psylla sucks on the leaf and can therefore easily transmit bacteria and viruses to the plant.
After overwintering, from early spring the adult females lay their eggs in the young leaves and flowers. Larvae hatch from these eggs. The pear psylla has five larval stages. The adult emerges after the fifth stage. On average four or five generations develop in any one calendar year, overlapping each other. At higher temperatures (20°C - 25°C) the life cycle of these psyllas is 30 to 35 days.
- The honeydew secreted can attract harmful fungi. Honeydew also means visual damage.
- The sucking insects can transmit bacteria and fungi to the plant.
- In spring, the psyllas are active on the young leaves and young flowers. In summer they especially occupy the new shoots.