Rhynchites auratus (Scopoli)
Taxonomic position: Insecta, Holometabola, Coleoptera, Rhynchitidae.
(Formerly placed in the family Curculionidae).
Common name: Apricot weevil, golden green snout beetle.
Geographical distribution: Eastern Mediterranean to southern Russia.
Morphology: The adult is 7-9 mm in length, golden-red and hairy; legs and rostrum brown. Elytra regularly punctate. Larva 12 mm long, white except brown head, body curved and apodous.
Host plants: Several species of Prunus, like sweet cherry (P. avium L.), and other fruit trees, including apple.
Life history: The adults appear in early spring and initially feed on the blossoms of cherries and other Rosaceous trees. Later they bore holes in young fruits into which eggs are placed; each female producing 90-150 eggs. They hatch within a few weeks and the emerging larvae bore within the fruit and move towards the stone (the seed) to feed on it. Later the larvae drop to the soil, wherein pupation takes place. Overwintering is either as pupae or as adults, which hide in tree crevices or under its loose bark. In Syria and Lebanon the pest has a single annual generation.
Economic importance: Attacks on green fruits can be seen as small holes (the egg-laying scars); there is no other external sign. However, severely damaged fruits drop, and those that attain maturity are pierced down to the stone. Sweet cherries may suffer 10-85% infestations and apples up to 60%. Varieties with small fruits are more heavily damaged.
Management
Monitoring: The presence of 3 weevil adults/10 cherry branches would indicate the need for a chemical treatment.
Chemical control: Sprays with or organophosphate or with pyrethroids are effective.
References
Andreev, R., Kutinkova, H. and Baltas, K.. 2009. Non-chemical control of some important pests of sweet cherry. Journal of Plant Protection Research 48: 503–508.
Khairushev, E. K. 1970. The cherry-fruit weevil (Rhynchites auratus). Zashchita Rastenii 15,12: pp. 41 (in Russian with an English Abstract).
Kutinkova, H. and Andreev, R. 2004. Integrated pest management in sweet cherry (Prunus avium L.) orchards in Bulgaria. Journal of Fruit and Ornamental Plant Research 12: 41-47.
Özbek, H., Güçlü, Scedilla, and Hayat, R. 1996. Investigations on the phytophagous and predator insect species on stone fruits in the north-east agricultural region of Turkey. Turkish Journal of Agriculture & Forestry 20: 267-282 (in Turkish with an English abstract).
Talhouk, A.M. 2002. Insects and Mites Injurious to Crops in Middle Eastern Countries, 2nd Edition. American University of Beirut Press.