Pests
Laspeyresia nigricana Fabricius - Pea moth
Systematic position.
Class Insecta, order Lepidoptera, family Tortricidae, subfamily Olethreutinae, tribe Grapholitini, genus Cydia.Synonym.
Cydia nigricana Stephens.Grapholita nigricana F.
Biological group.
These are oligophagous pea pests.Morphology and biology.
The moth's wing span is about 13-17 mm. Front wings are dark-brown or brown-gray with metallic shine. There are some light stripes (7-12) near the front wing border, decreased from external border to its base. Between stripes dark touches are located, perpendicular to external border. Some dark spots and white comma-like spots are near the hind wing border. Hind wings are white-yellow (brown near hind border). The oval egg (0.75-0.8 mm) is flattened on one side. At first, it has a white color and then it becomes yellow. In the end the color turns dark. The larva reaches 14 mm long. At first it is white, then yellow with dark head and anal scutellum. It has eight lines of dark warts with hairs. Larva also has 8 pairs of legs (3 pairs on thorax). The body length of yellow-brown pupae varies from 5 to 7 mm. The over-wintering takes place during the phase of 5th-instar larvae, within dense oval cocoon in ground on fields of pea, lentil, peavine and vetch. An insignificant number of caterpillars over-winter in places where grain is dried and threshed. The insects pupate, in their cocoons, underground during the month of May. The pupae period lasts 10-18 days. The first moths appear during the period of wild vetch and pea-vine blooming. When first buds appear, the moths are found on pea. After coupling, which takes place 4-7 days after emergence from cocoon, the insects begin to lay eggs. Additional feeding on pea flowers is preferred. Moths fly in the evening; they live 10-14 days. Mass oviposition occurs at the beginning of July. The oviposition lasts 25-30 days. Pests lay eggs in groups of one, two or three (rarely four) on upper leaves (lower side), peduncle, bell, stems. Embryonic development lasts 6-10 days. Fecundity reaches 200 eggs. Hatching caterpillars penetrate into the pods and gnaw grains from above, making wide channels, ending in a hollow at one end. They soil the grain with fecal masses and cobwebs. Usually, one, rarely two or more (up to four) caterpillars are located in pods. The entire larval period (lasting 16-25 days) occurs inside one pod. The larvae have five instars, four molts. Then the insect makes a hole in the pod wall and comes out, making a cocoon in the ground. This take place when the pods become mature and the plants become dry (from the end of July and up to the first ten-day period of September). Young caterpillars (not 5th instar) that didn't finish their feeding can diapause, but eventually they perish.Distribution.
The insect is widespread in West, Central and South Europe up to Minor Asia; in the southern part of North Europe up to Asia Minor; in USA, Canada. Within the territory of the Former Soviet Union the species occurs widely: in the European part of Russia, in Byelorussia and the Baltic states. Northern border of the area reaches 61-62°N; eastern border, usually, is Irtysh. Some nidus. are located in Kemerovo and Krasnoyarsk regions; Primorskii, Pribaikal, Priamur Territories. The species occurred in northern regions of Ukraine, in the north of Kazakhstan. High harming activity has been reported in the Non-Chernozem zone of the European part of Russia.Ecology.
Insect development depends on weather conditions. Moth appearance is inhibited by soil temperatures. The activity of adult insects depends on the intensity of light and air temperature. The most favorable conditions for these insects are a temperature of 21-25°C and relative humidity of 70-90%. The sum of effective temperatures for insect development is 442°C; the minimum effective temperature is 12-13°C. Moth vitality decreases at a temperature of more than 32°C. Hot and dry weather is bad for the insects, because the plants rapidly mature, dry out and insects cannot feed normally. Frequent rains prevent the moth from flying and wash off the eggs and caterpillars. The beginning of over-wintering coincides with a constant average daily temperature of 11°C and length of day at 14 hours. The species is monovoltine. During favorable weather conditions the caterpillars of the second generation can appear, but eventually they perish. The species is flexible and can develop within a wide spectrum of temperatures and humidity levels. Diapaused insects are cold-resistant. They can survive at low temperatures (-13-14°C) for a long period. Snow is necessary for good over-wintering of the pest.Economic significance.
Species causes damage to pea and lentil, feeding on grains. The weight of grains decreases. These grains are not suitable for sowing. The pest can also feed on horse latipudes, chick-pea, lupin, babies'-slippers, wild vetch and yellow atrophy. Control measures include forecasting of pest appearance, early sowing of grains, sowing early types, shortening period between harvesting and threshing, using mixed crops (with barley), deep under-winter plowing (using plough with coulter), eradication of weeds, insecticide treatments, and use of Trichogramma evanescens Westw.Reference citations:
Antsiferova T.A., Dobrosmyslov P.A. 1966. To damage of pea moth. In: Antsiferova T.A., ed. The proceedings of Mordov State University, N. 54. Saransk: Moscow State University. 82-95 p. (In Russian)Arkhipov G. 1965. The pea moth-dangerous pest. Zernobobovye cultury, 6: 36-7. (In Russian)
Arkhipov G.E. 1967. The pea moth (Laspeyresia nigricana Steph.) and factors restricting its number and damage in Chuvash ASSR region conditions. PhD Thesis. Leningrad: VIZR. 17 p. (In Russian)
Arkhipov G.E. 1969. The features of pea moth development. In: Polyakov I.M., ed. The proceedings of 5th scientific conference of young scientists. Leningrad: VIZR. 66-9 p. (In Russian)
Chislov M.E., Turaev N.S. 1975. Trophic connections of pea moths in Middle Ural. In: Turaev N.S., ed. The proceedings of Sverdlovsk Agricultural Institute. Perm': Sverdlovsk Agricultural Institute. V. 35: 96-8. (In Russian)
Chmyr' P.G. 1968. Biological features of pea moth. Zashchita rastenii, 10: 47. (In Russian)
Eenlaid A. 1953. The significance of pea moths Laspeyresia dorsana F. and L. nigricana Steph., that are the pea pests, their biology, ecology and possibilities of control. PhD Thesis. Tartu: Tartu University. 25 p. (In Russian)
Gorbunova N.N. 1963. Control against pea moth. Sel'skoe khozyaistvo Byelorusii, 16: 9. (In Russian)
Kagan F. 1968. The methods for forecasting and calculation of control dates against pea moth. In: Polyakov I.M., ed. The proceedings of scientific-methodical conference on problem "the methods for forecasting of main pests and diseases on agricultural plants and signalling of treatments dates". Leningrad: ViZR. 144-5 p. (In Russian)
Lipskii B.A. 1938. Pea moths and their control. In: Bagdanov-Kat'kov N.N., ed. The proceedings of Leningrad region plant protection station. 24 p. (In Russian).
Lukina M.I. 1970. Pea moth (Laspeyresia nigricana Steph.) and elaboration of complex control measures against it. PhD Thesis. Moscow: TSKhA. 22 p. (In Russian)
Nikitina T.F., Shcherbinina G.I. 1968. Pea moth. In: Oleshko V.D., ed. The proceedings of Kostroma Agricultural Institute, N. 9. Yaroslavl': Kostroma Agricultural Institute. 67-72 p. (In Russian)
Nikitina T.F., Shcherbinina G.I. 1970. The biophenology of pea moth and effectiveness of some treatments against it. In: Oleshko V.D., ed. The proceedings of Kostroma Agricultural Institute, N. 19. Kostroma: Kostroma Agricultural Institute. 67-72 p. (In Russian)
Ozols E.Ya. 1950. The influence of climatic conditions on mass reproduction of pea moth Laspeyresia nigricana Steph. in Latvian SSR. In: Koshik A.K., ed. Mass reproduction of animals and it forecasting. Part I. Kiev: Kiev university publishing house. 150 p. (In Russian)
Petrukha O.I. 1935. To biology of pea moth Laspeyresia (Grapholita) nigricana Steph. In: Panasyuk M.P., ed. The proceedings Belotserkov' selection station, XLVI. 113-21 p. (In Russian)
Povalikhina A.A. 1963. On duration of damaging by pea moth and its harmfulness in Kaliningrad region. In: Ozols E.Ya., ed. Brief totals of scientific researchs on plant protection in Baltic zone of SSSR. Riga: Zvaigzne. 13-5 p. (In Russian)
Turaev N.S., Volov L.M. 1977. Distribution and harmfullness of pea moth in Ural. In: Turaev N.S., ed. The proceedings of Sverdlovsk Agricultural Institute. Perm': Sverdlovsk Agricultural Institute. V. 50: 38-43 p. (In Russian)
Turaev N.S., Volov L.M., Chislov M.E. 1977. In: Turaev N.S., ed. The proceedings of Sverdlovsk Agricultural Institute. Perm': Sverdlovsk Agricultural Institute. V. 50: 3-38. (In Russian)
Volov L.M. 1979. The pea moth in Middle Ural and control treatments with it. PhD Thesis. Leningrad: VIZR. 16 p. (In Russian)
Zatyamina V.V. 1976. Pea moth. In: Lakhidov A.I., ed. The method for forecasting and calculation of diseases and pests development on field cultures in the Central Black Earth zone. Voronezh: Central Black Earth Publishing House. 85 p. (In Russian)