- The scientific name : parlatoria oleae
- the family : homoptera
- Symptoms of the disease :
- The insect attacks the vegetative organs, sucks the juice from them, and causes deformation of the leaves. A dark (violet) color spot appears on the fruits, in the middle of which the peel appears.
- Description of the insect:
The color of the insect is purple and is covered by a gray shell with a black umbilicus on the sides, diameter (0.9 mm). The shape of the shell is oval for the female insect and elongated for the male.
- The causes of disease :
- Excessive irrigation, continuous heavy rainfall, high ground water levels
- Poor use of insecticides can eliminate a large portion of parasites and cause natural imbalance
- Conditions suitable for the spread of the disease :
- High temperatures are appropriate for the development and reproduction of the pest and the formation of its crust.
- Fluctuation and irregularity of humidity helps lentigines to a great extent.
- The presence of other pests in the field, such as red spiders and whiteflies, greatly contributes to infection
- Disease development cycle:
- Eggs are laid between March and October, with peak numbers observed in June. At 24 and 30°C, females lay an average of about 124 and 105 eggs each, but egg production.. Although adult males live for only 1-3 days, females generally live for 1-2 months or more.
- The nymphs emerge from under the female's shell and spread across the plant and begin to secrete the protective shell. The life cycle of the first generation is completed in June, and the life cycle of the second generation is completed in October, where the adult insects lie under their shell until the beginning of next spring.
- Losses of disease spread
- When the insect attaches to a plant, it secretes a toxic liquid that causes the plant tissue to turn from dark red to almost black. This may reduce the commercial value of crops
- Olives may suffer from a certain decrease in the amount of oil.
- Control strategy
- Preventive measures to prevent the occurrence of the disease
- High temperatures range between 30°C and 35°C, which reduces the duration of egg laying and the number of eggs.
- Light pruning.
- Plowing the soil and applying organic fertilizer.
- Chemical and organic control recommendations
- Using parasitology (by two apheline parasites, Aphytis paramaculicornis and Coccophagoides utilis
- Oil emulsion in the spring, before the leaves appear
- Lime sulfur is an insecticide but is not suitable for use near homes.
- References
- Biche, Mohamed, and Mahdi Selami. “Biology of Parlatoria oleae (Homoptera, Diaspididae) in the area of Cap-Djinet (Algeria).” Agriculture and Biology Journal of North America 2.1 (2011): 52-55
- Habib, A., Salama, H. S., & Amin, A. (1969). The biology of the plum scale, Parlatoria oleae (Colvee)(Coccoidea: Diaspididae). Bulletin of the Société Entomologique d'Egypt, 53, 283-297.
- MCCONNELL, H. S., et al. Parlatoria oleae Colv., a privet pest in Maryland. Journal of Economic Entomology, 1930, 23.1: 142-144.
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