Recognizing Icerya purchasi:
Icerya is a pest species on several ornamental plants groups such as Pittosporum, Albizia and Mimosa. Icerya seems a bit like mealybugs but they are really different, belong to a different pest genus. The adult female lives on branches of woody shrubs and produces big, white egg-masses with longitudinal ridges. Within the egg mass there are hundreds of eggs. Nymphs hatch from these eggs and spread themselves all over the plant in search for a proper place to sit and feed. They prefer younger twigs. During development they moult several times. For each moulting the nymphs find themselves a new place. The older the nymphs get the more they prefer wooden parts of the shrub. All stages produce lots of honeydew. Plants get very sticky when they are infested by Icerya. Fungus may start growing on the honeydew making plant even more dirty.
All stages are plant sucking which causes inhibited growth and malformation. Main damage is caused by the big number of waxy threads and honeydew excretion. Photosynthesis may be seriously hampered by fungus growing on the honeydew.
- hundreds of eggs per female in big, white waxy egg mass
- egg mass has clearly visible longitudinal ribs
- eggs are orange, crawlers red, nymphs red-brown with yellow spots
- development time egg - adult 6 - 8 week
- in greenhouse several generations a year
- reproduction mainly hermaphrodite, males are very rare
Host plants Icerya;
- more than 50 host plants, mainly woody ornamental shrubs