Euzopherodes vapidella (Mannerheim)
(Sometimes placed in the genus Ephestia).
Taxonomic placing: Insecta, Holometabola, Lepidoptera, Pyralidae.
Common name: Citrus stub moth, yam moth.
Geographical distribution: Europe, Western and North Africa, the Middle East.
Host plants: Citrus, carob (Ceratonia siliqua Linnaeus), yam (Dioscorea alata Linnaeus).
Morphology: Body of adult 5-8 mm long, forewings red-brown with obscure markings, hindwings white. Body of larva white-yellow, 8-10 mm long, with long setae, head brown.
Life history: At 29ºC the pest raises a generation in 3-4 weeks, laying 80-120 eggs/female on citrus stubs or grafting wounds, on wounded olive bark or yam tubers. Neonate larvae penetrate beneath of the bark to feed. On yam they place their eggs on wounds or pierce the skin of tubers to lay eggs. They can complete 4-5 annual generations in the field.
Economic importance: The larvae (caterpillars) feed beneath and around the bark and stubs of citrus seedlings, sometimes girdling them, causing them to dry up and/or to break off. The leaves of infested olive trees turn yellow and tree growth may decline. The moths are post-harvest pests of yam tubers, especially during the first four months of storage. The larvae tunnel into the tubers, causing deterioration, reducing the value of the crop and even total loss after one month of storage.
Management
Monitoring. The presence of faecal pellets and gum near and under the bark of citrus trees and seedlings and of faecal pellets woven together by silk threads on yam tubers indicate the presence of the pest.
Horticultural methods: Grafted citrus rootstocks are to be pruned to their bases and the wounds treated with grafting wax; likewise with wounds on olive trees. Storage facilities for yam tubers should be cleaned and even disinfected prior to storage, which is to be at low temperatures (but higher than 12ºC to avoid damage to tubers). Only tubers without any signs of damage should be stored.
Chemical control: Organophosphates and pyrethroids have been applied onto stored tubers. Oil and ethanol extracts from several tropical plants inhibited egg hatch and adult emergence when applied to cut or damaged surfaces of yam tubers.
Biological control: The parasitoid Apanteles sp. (Braconidae) attacks the moth in Iran, and three ant species fed on the larvae, but their controlling effect is not known.
References
Akinneye, J.O. and Ashamo, M.O. 2006. Some aspects of the biology of the yam moth, Euzopherodes vapidella Mann (Lepidoptera: Pyralidae), a pest of stored yam tubers in Nigeria. Journal of Entomological Research 30: 59-63.
Alemansoor, S., Alehosein A. and, Keyhanian, A. 2012. Biological characteristics of yam moth, Euzopherodes vapidella vapidella Mann (Lepidoptera: Pyralidae) xylophagous pest of olive orchards in the Fars province, Iran. Proceedings 20th Iranian Plant Protection Congress, Shiraz- Iran.
Ashamo, M.O. and Odeyemi, O.O. 2001. Effect of rearing temperature on the fecundity and development of Euzopherodes vapidella Mann (Lepidoptera: Pyralidae), a pest of stored yam. Journal of Stored Products Research 37: 253-261.
Ashamo, M.O. and Akinneye, J.O. 2004. The insecticidal activity of some extracts and oils of some tropical plants against the yam moth Euzopherodes vapidella Mann (Lepidoptera: Pyralidae). Ife Journal of Science 6: 10-13.