Pests
Pandemis ribeana Huebner - Barred Fruit-tree Tortrix
Systematic position.
Class Insecta, order Lepidoptera, family Tortricidae, subfamily Tortricinae, tribe Archipini, genus Pandemis.Synonyms.
Pandemis cerasana Hbn., Pandemis chlorograpta Meyr.Biological group.
This species is a Polyphagous pest of rosaceous fruit and berry cultures and forest plantations.Morphology and biology.
Fore wings ocher-yellow or light brown with yellowness, having indistinct reticulate pattern (wingspan 15-24 mm). Pretornal area, oblique median band, and semicircular or triangular sub-apical spot are somewhat darker, brownish and distinct. Hind wings dark gray, with yellow anterior margin. Eggs are oval, lentiform, light green. Caterpillars of younger instar light- or yellow-green. Elder instar caterpillars are light-green or green. Pupa are 11-14 mm long, light brown with darker back. Cremaster is conical with transverse furrows. Average fertility is 200-270 eggs for females of wintered generation, 80-165 eggs for females of summer generation; sometimes females are sterile. Eggs are laid in groups (shields) on the upper surface of leaves mainly, less often on bark and fruits, in the upper and middle parts of crowns. Female lays up to 6 batches, up to 180 eggs in a batch. Embryonic development lasts 7-10 days. Wintered caterpillars feed on blossoming buds in the beginning, especially at the tips of twigs, gnawing out buds and flowers. In older instars they fold leaves along main veins or pull them together in bundles, gnawing around ovaries and fruits. In autumn until winter they usually sceletonize leaves from below, under their wrapped edges, or near veins. Pupation occurs in feeding places on plaited leaves. Diapausing caterpillars of 3rd, less often 4th instar, winter in dense silky cocoons among bark crevices on trunks mainly at heights up to 1 m above the ground, less often in branch forks at base of buds.Distribution.
Occurs in Western Europe (everywhere), Asia Minor, Iran, Mongolia, China, Japan, the Himalayas; Northern America (adventive). In the former USSR it is found in the European part (from White Sea coast to the Caucasus), in Transcaucasia, Kazakhstan, southern Siberia, in the south of the Far East.Ecology.
The species is monovoltine north of Ryazan Region, bivoltine in the south (2nd generation is incomplete). In spring the over-wintered caterpillars appear and restart their feeding when the apple buds blossom, i.e., at average daily air temperature of 10-14°C, usually at the end of April or in the 1st third of May. Phenology varies in different areas; caterpillars develop slowly. In Byelorussia caterpillars are found in May to the 1st third of June and in July; pupae occur at the end of May to the 1st half of June and in the 1st half of August. In Crimea pupation begins in middle of May. In Moldova the majority of caterpillars (65-75%) stop feeding in June through the beginning of July, braiding cocoons under bark or in bark crevices, and diapausing, then hibernating. The 1st generation moths fly from the middle of May until the middle of June, the moths of the 2nd generation fly in August through September. Males live 18-28 days, females 14-25 days.Economic significance.
This is a dangerous pest of gardens and forest plantations in steppe and forest-steppe zones of the former USSR, especially in Moldova and Ukraine. The species (together with other leaf rollers) caused harm to a lesser degree in the Leningrad and Moscow regions, Latvia and Byelorussia (not included into the low damage zone). Polyphagous caterpillars damage all rosaceous fruit and berry cultures, especially apple, forest plantations and landscape cultures. Damaged ovaries fall down and fruits are deformed or rotted.Control measures.
Agronomical measures include pruning old and diseased branches. Biological measures include application of biological preparations. Chemical measures include local insecticide treatments during development of 2nd-instar caterpillars before flowering and in summer during development of caterpillars of the 2nd generation. Monitoring and forecast are possible with the use of pheromone traps.Reference citations:
Ermolaev V.P. 1988. Tortricidae. In: Kirpichnikova V.A., Ler P.A., eds. Butterflies - pests of agriculture in the Far East. Keys. Vladivostok: Biology and Soil Institute, DO AN SSSR. 65-99 p. (In Russian)Galetenko S.M. 1964. To morphology of fruit leafrollers. In: Kochkin M.A., Rubtsov N.I., Ryndin N.V., eds. 150 years to State Nikitskii botanical garden. Collection of scientific works. V. 37. Moscow: Kolos. 531-395 p. (In Russian)
Kostyuk Yu.A. 1974. Family Tortricidae. In: Vasil.ev, V.P., ed. Pests of agricultural crops and forest plantations. V. 2. Arthropods. Kiev: Urozhai. 261-320 p. (In Russian)
Kostyuk Yu.A. 1980. Tortricidae. Issue 10. Tortricinae. In: Dolin V.G., ed. Fauna of Ukraine. V. 15. Kiev: Naukova dumka. 424 p. (In Ukrainian)
Kuznetsov V.I. 1994. Family Tortricidae. In: Kuznetsov, V.I., ed. Insects and mites - pests of agricultural plants. V. 3(1). Lepidoptera. St. Petersburg: Nauka. 51-234 p. (In Russian)
Litvinova A.N. 1969. On preferences to host plants in caterpillars of dendrophilous leafrollers (Lepidoptera, Tortricidae). Vestsi Akademii navuk BSSSR. Seryya byalagichnykh navuk (Minsk: Navuka i tekhnika), 4: 107-109. (In Russian)
Savkovskii P.P. 1976. Atlas of the pests of fruit and berry plants. Kiev: Urozhai. 207 p. (In Russian)
Vasil.ev V.P., Livshits I.Z. 1984. Pests of fruit crops. Moscow: Kolos. 399 p. (In Russian)