Pests
Chaetocnema concinna Marsh. - Mangold Flea Beetle
Systematic position.
Class Insecta, order Coleoptera, family Chrysomelidae, genus Chaetocnema Steph.Synonym.
Ch. heikertingeri Lubisch.Biological group.
This species is a pest of sugar and fodder beet; also causes damage to buckwheat, spinach and sorrel to a lesser degree.Morphology and biology.
This species has a body length of 1.5-2.3 mm. Female is somewhat bigger than male. The 1st segment of male fore tarsus is 1.3-1.4 as wide as 2nd one. Body is green in color, upper side with reddish or greenish metallic shine, fore and middle femur black, tibia and tarsus dark-brown. Frons has a median carina. Pronotum along basal margin has a row of punctures and slightly oblique impressions. Middle and hind tibia in outer apical 1/3 with emargination covered with short hairs. Beetles appear at the end of March or in April at temperatures of 8-9°C, and eat leaf parenchyma. Propagation begins at 19.5°C. Oviposition occurs from the 1st third of June until the end of July. Female lays eggs in groups of 2-6 in the soil near host plants at a depth of 3-5 cm. Fertility is about 40 eggs. Polygonum lapathifolium L. is the most attractive plant for females. Development of eggs lasts 11-13 days. Larva eats mainly roots of P. lapathifolium, buckwheat, and hemp; also sorrel and rhubarb to a lesser degree. Pupation occurs in soil. Adults of new generation appear at end of summer, migrating in the middle of September to forest belts and in sod for hibernation.Distribution.
This species inhabits Europe, Asia Minor, Northern Africa and was introduced into North America. In the former USSR it is widely distributed from the west borders of the Ukraine east to Kuril Islands.Ecology.
Polyzonal species, being distributed from taiga to steppe. In arid climates it usually occurs in agrocenosis. In May-July adults are concentrated on Rumex, Polygonum, and Rheum. In spring they stay on sugar-beet crops for more than 2 weeks. Beetles migrate to Polygonaceae plants, when 4-5 leaves appear on sugar-beet seedlings. The species is monovoltine in major areas, being perhaps bivoltine in southern regions.Economic significance.
This insect causes damage while in adult stage. Damage is increased after drought. Control measures include sowing sugar-beet at earliest time, using fertilizers to accelerate seedling development and eradication of weeds from fields. Pesticide treatment is necessary in spring after the beetles. mass emergence following hibernation.Reference citations:
Dubeshko L.N., Medvedev L.N. 1989. Ecology of leaf beetles from Siberia and the Far East. Irkutsk: Irkutsk University. 224 p. (In Russian)Konstantinov A.S. 1988. Landscape-zonal peculiarities of the Chaetocnema beetles distribution (Coleoptera, Chrysomelidae). Vestnik Zoologii, 6: 44-47. (In Russian)
Kopaneva L.M., ed. 1981. Keys to harmful and useful insects and mites on the industrial crops in the USSR. Leningrad: Kolos. 272 p. (In Russian)
Lopatin I.K. 1977. Leaf beetles (Chrysomelidae) from Middle Asia and Kazakhstan. Leningrad: Nauka. 289 p. (In Russian)
Lopatin I.K., Kulenova K.Z. 1986. Leaf beetles (Coleoptera, Chrysomelidae) from Kazakhstan. Alma-Ata: Nauka. 199 p. (In Russian)
Lubischev A.A. 1963. Two new Palearctic species of the genus Chaetocnema of the group Ch. concinna March. (Coleoptera, Chrysomelidae, Halticinae). Entomol. Review, 42(4): 858-863. (In Russian)
Medvedev L.N. 1982. Leaf beetles of the Mongolia, Key. Moscow: Nauka. 304 p. (In Russian)
Medvedev L.N. 1992. Family Chrysomelidae - leaf beetles. In: The key to insects from the Far East of the USSR. V. 3. Coleoptera, or beetles. Part 2. St. Petersburg: Nauka. 704 p. (In Russian)
Medvedev L.N., Ammosov Yu.N. 1978. Fauna of leaf beetles (Coleoptera, Chrysomelidae) and the cardinal zoogeografical peculiarities. Ecofaunistical investigations of insect from Yakutia. Yakutsk: Yakutsk filial SO AN SSSR. 113-128 p. (In Russian)
Palii V.F. 1959. Leaf beetles. In: Sveklovodstvo. Pests of sugar-beet and control measures. Kiev: Sel'khoz lit. Ukr. SSR. 155-170 p. (In Russian)
Palii V.F. 1961. Fauna of pest flea beetles from the USSR. Frunze: AN Kirgiz. SSR. 101 p. (In Russian)
Putele V. 1970. Fauna of the flea beetles from Latvian SSR. Materials of 7th Baltic meeting on plant protection (part 2). Pests of agricultural and forest plants and their control. Elgava: Latvian Ministry of Agriculture. 17-20 p. (In Russian)
Shutak V.I. 1973. Numerous pests of flea beetles from the Bashkiria and South of Cis-Ural. Science for production (collection of works). Voronezh: Minsel.khoz. 85-88 p. (In Russian)
Zverezomb-Zubovskii E.V. 1956. Pests of sugar-beet. Kiev: AN Ukr. SSR. 276 p. (In Russian)