Euzophera osseatella (Treitschke)
Taxonomic placing: Insecta, Holometabola, Lepidoptera, Pyralidae.
Common name: Eggplant stem borer.
Geographic distribution: Europe and the Mediterranean region.
Morphology: The adult is 10-13 mm long, body light brown, forewings pale brown, with a dark spot at the center and undulating brown lines at their distal parts. Hindwings white-grey with a dark line along their margins. Body of larva 15-20 mm in length, white-grey, head brown.
Host plants: Solanaceae, such as, eggplant, pepper, potato and tomato.
Life history: Females lay their eggs (up to 200/female) on the host-plant stems wherein the emerging larvae bore, moving down towards the roots. They may also excavate galleries in potato tubers, and pupate at their feeding sites. The adults live for 1-2 weeks and fly by night. The threshold of development was calculated to be at around 11ºC and the development of one generation may acquire 930 day degrees. The pest raises 5 annual generations.
Economic importance: The boring of one or more larvae in eggplant stems affects plant vigor, weakens the stems and reduces yield. Rot microorganisms invade the plants and further reduce their health. Tomato fruits are tunneled and yield may be reduced by 25%. Rates of infestation depend on the availability of the hosts in various regions, thus potatoes are heavily damaged during early summer and eggplants during summer and autumn.
Management
Host resistance: Various Egyptian eggplant cultivars are partially resistant to E. osseatella.
Biological control: The pest is attacked by the parasitoids Cremastus ornatus (Szépligeti), Pimpla roborator Fabricius and Angitia sp. (Ichneumonidae) and by Chelomus sulcatus Jurine (Braconidae).
References
Ali, M.A., Essa, A.Es., Abd El-Wahab, H.A. and Ooda, M. 2011.Thermal constant and degree-day requirements for the development of the development of the eggplant stem borer, Euzophera osseatella Triet. (Lepidoptera: Pyralidae). Egyptian Journal of Agricultural Research 89: 899-905.
El-Sherif, S.I. 1971. Infestation rates and annual generations of Euzophera osseatella Treit. (Lepid., Pyralidae) under field conditions in Alexandria area. Zeitschrift für Angewandte Entomologie 69: 37-43.
Harakly, F. A. 1965. External morphology and life –history of egg-plant stem borer, Euzophora osseatella Treit. (Lepidoptera, Pyralidae). Bulletin of the Egyptian Entomological Society 49: 259-276.
Rivnay, E. 1966. A Contribution to the biology of the eggplant borer Euzophera osseatella Tr. (Pyralidae Lep.). Israel Journal of Entomology I: 1- 13.