Ephestia elutella Hübner
Common names: Chocolate moth, warehouse moth, tobacco moth.
Systematic position: Insecta, Holometabola, Lepidoptera, Pyralidae.
Morphology: The color of the larvae depends on their diet; those reared on tobacco may be yellowish, others are brownish, pinkish or off-white. The head and pronotum are reddish-brown, and the body, which is 10-15 mm in length, bears minute brown dorsal tubercles that carry single setae. The adults are brown-red, forewings grey with 2 transverse white lines, hindwings grey, body length 15-20 mm.
Distribution: Cosmopolitan, more common in cooler regions.
Life history: The females lay several hundred eggs, dependent on the diet. The eggs hatch within a week, and the larvae burrow into the food, wherein they develop, spin silken webs and remain for several months. At the fifth instar they leave the food to climb onto various surfaces, often reaching ceilings and enter diapause. During diapause they are very tolerant to extreme temperatures and humidities. A generation can be completed in 1-3 months, the pest raising a single generation in cool regions, up to 3 in warmer climates.
Economic importance: The larvae feed on many stored products, including grains, cocoa beans, dried fruit, coffee, and many others, causing much damage. The damage is mainly due to the extensive webbing and frass. In Turkey E. elutella is a major pest of stored tobacco.
Management
Monitoring: Pest population density and fluctuations can be monitored with adhesive vertical paper stripes that release an appropriate pheromone.
Fumigation: Exposures of about one day to sulfuryl fluoride or phosphine killed all larvae and pupae.
Chemical control: Dichlorvos, applied daily as an oil mist, provided good control.
Biological control: Trichogramma evanescens Westwood parasitized about 78% pest eggs, down to a depth of 5 cm in bulk wheat. Another common parasitoid is Habrobracon hebetor. Both parasitoids reduced pest populations by >30%. Blattisocius tarsalis is an important egg predator.
References
Ashworth, J.R. 1993. The biology of Ephestia elutella. Journal of Stored Products Research 29:199-205.
Baltaci, D., Gerowitt, B., Drinkall, M.J. and Reichmuth, Ch. 2009. Lethal effects of sulfuryl fluoride on eggs of different ages and other life stages of the warehouse moth Ephestia elutella (Hübner) Journal of Stored Products Research 45: 19-23.
Bell, C.H. 1992. Time, concentration and temperature relationships for phosphine activity in tests on diapausing larvae of Ephestia elutella (Hubner) (Lepidoptera: Pyralidae). Pesticide Science 35: 255-264.
Buchelos, C.Th. and Trematerra, P. 1998. Monitoring of stored tobacco insect pests by means of pheromones: the case of Ephestia elutella (Hübner) and Lasioderma serricorne Fabricius in South Europe. Anzeiger für Schädlingskunde, Pflanzenschutz, Umweltschutz 71: 113.
Coskuncu, K.S. and Kovanc, B. 2009. Seasonal fluctuations in populations of Lepidopteran species as influenced by conventional control in tobacco stores. Journal of Food Agriculture and Environment 7: 839-842.
Green, A.A., Kane, J., Heuser, S.G. and Scudamore, K.A.1968. 1968. Control of Ephestia elutella (Hb.) (Lepidoptera, Phycitidae) using dichlorvos in oil. Journal of Stored Products Research 4: 69-76.
Schöller, M. 2000: Forager in the rye: Biological control of Ephestia elutella in bulk grain. IOBC/wprs Bulletin 23: 149-159.
Schöller, M., Hassan, S.A. and Reichmuth, C. 1996. Efficacy assessment of Trichogramma evanescens and T. embryophagum (Hym.: Trichogrammatidae), for control of stored products moth pests in bulk wheat. Entomophaga 41:125-132.
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