Spilonota ocellana (Denis & Schiffermüller)
Common name: Eye-spotted bud moth.
Systematic position: Insecta, Holometabola, Lepidoptera, Tortricidae.
Morphology: The larvae are 9-13 mm in length, body mostly dark-red to brown, head and prothorax black, legs dark brown. Adult body about 9 mm in length, mostly brown. Forewings with proximal and distal parts brown, middle part grey, but with an anterior dark blotch. Hindwings uniformly grey.
Distribution: North America, North Africa, Europe, Iran, Turkey and Cyprus and Far East,
Host plants: Mostly Rosaceae but also plants in other families.
Life history: Spilonota ocellana completes 1-2 annual generations, dependent on the region. Females lay eggs singly on leaves, whereon the newly hatched larvae feed. Elder larvae construct and enter a webbed protective covering (hibernaculum), usually next to a spur, wherein they overwinter. They resume feeding in spring, consuming buds (hence their common name), blossoms and leaves. The larvae also nibble on apple fruits, causing tiny, shallow circular wounds on the fruit surface. They pupate between leaves, near the feeding site and the adults (of the monovoltine population) emerge by mid-summer. The bivoltine adults emerge earlier and raise the second generation in late summer.
Economic importance: Spilonota ocellana is an important pest of young Rosaceous fruit trees, such as almond, apple, apricot, pear, plum and others. Apple losses can reach 50%, due to shallow wounds on the face of apples, to the destruction of buds and to boring into growing shoots, which results in restricted growth or abnormal tree form.
Management
Monitoring: Pheromone traps are used for forecasting.
Horticultural methods: Pruning and removing old and diseased branches.
Mating disruption: Pheromone‐based mating disruption of the pest in a North American apple orchard resulted in 95% mating reduction of virgin females.
Chemical control: Due to chemical sprays applied against other orchard pests, there is seldom need for such applications.
Biological control: The egg parasite Trichogramma embryophagum (Hartig)) may attack up to 50% of the pest’s eggs in Turkey. About half a dozen other hymenopterous parasites are known from North America. Applications of Bacillus thuringiensis resulted in smaller pest larvae, retarded development and higher mortality. A North American nuclear polyhedrosis virus disease of S. ocellana usually killed less than 10 per cent of the pest population
References
Bulut H, 1990. Investigations on the distribution and natural effectiveness of Trichogramma embryophagum (Hartig) in the eggs of Hedya nubiferana and Spilonota ocellana F. Proceedings of the Second Turkish National Congress of Biological Control. Izmir, Turkey: Ege Universitesi, pp. 25-35.
Swain, J.A. 2016. Impact of temperature and relative humidity on the eye-spotted bud moth, Spilonota Ocellana (Lepidoptera: Tortricidae): a climate change perspective. M.Sc. thesis, Simon Fraser University, pp. 87.
Jaques, R.P. and Stultz, H.T. 1966.The influence of a virus disease and parasites on Spilonota ocellana in apple orchards. The Canadian Entomologist 98: 1035-1045.
McBrien, H.L., Judd, G.J.R. and J. H. Borden, J.H. 1998. Development of pheromone‐based mating disruption for control of the eye‐spotted bud moth, Spilonota ocellana. Entomologia Experimentalis et Applicata 88: 101-107.
McBrien, H.L. and Judd, G.J. 2004. Emergence of overwintered larvae of eye-spotted bud moth, Spilonota ocellana (Lepidoptera: Tortricidae) in relation to temperature and apple tree phenology at Summerland, British Columbia. Journal of the Entomological Society of British Columbia 101: 15–28.
Oatman, E.R. and Legner, F.E. 1962. Bionomics of the eye-spotted bud moth, Spilonota ocellana, on cherry in Wisconsin. Journal of Economic Entomology 55: 930-934.
Oatman, E.R. and Legner, F.E. 1964. Additional studies of the effects of Bacillus thuringiensis on the eye-spotted bud moth, Spilonota ocellana. Journal of Economic Entomology 57: 264.
Sadava, D. and Miller C.D.F. 1967. Taxonomy of last-instar larval remains of parasites from Spilonota ocellana. The Canadian Entomologist 99: 436-442.
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