Agromyza oryzae (Munakata) - Japanese Rice Leafminer
Systematic position.Class Insecta, order Diptera, family Agromyzidae, subfamily Agromyzinae, genus Agromyza.
Synonyms.Oscinis oryzae Munakata, O. oryzella Matsumura, Agromyza oryzae Hd., A. oryzella Yuasa and Kouama
Biological group.Pest of rice.
Morphology and biology.Small black fly (body length 2.0-3.5 mm). Frons mat-black, ocellar triangle and orbits moderately shining. Orbital hairs directed backward. Cheeks wide, equal to 1/6 eye height. Third antennal segment obliquely emarginated, securiform; arista distinctly pubescent. Mesonotum black, slightly grayish, pollinose, with 6 pairs of dorsocentral setae and with acrostichal hairs in 6 rows. Legs black. Calypter yellowish-white, light brown at margin, with brown to black hairs. Larvae yellowish-white, to 5.5 mm in length. Each oral hook with 5 denticles. Anterior spiracles big, semicircular. Hind spiracles contiguous, surrounded with 4 pairs of tiny sensory papillae. Puparia of wintering and non-wintering generations differ in shape and color. Wintering puparia smaller, darker, more convex. Puparia winter. Female lays eggs on tips of young leaves by 2-3, more often one by one, under leaf epidermis. Larva moves downward, so the mine extends and occupies entire width of a sheet. Basal half of the sheet is never mined. The mine is white or light green in the beginning, then becoming brown or yellow, shrinking and drying. The mine maximal size is 11.5 cm in length, 9 mm in width. Larvae feed 10 to 44 days. Pupation occurs usually on a sheet outside the mine. Puparia of wintering generation fall down on ground where they winter.
Distribution.The species meets in China, Korea, Japan, Philippines, Taiwan. In the former USSR, it is found with confidence in the Far East only (Primorskii Territory). The species records by some authors on its distribution in Eastern Siberia, in the south of Ukraine and in the Northern Caucasus are not confirmed by taxonomists, not accompanied by the morphological description of insect development stages, by data on its bioecology and trophic specialization.
Ecology.Bivoltine species. Small part of the population gives a third generation. Imagoes appear from the end of May to the end of June. The greatest harm of larvae is observed in mid-July. Larvae of the 1st generation pupate in the second half of August. Before pupation they leave their mines, attaching to a green non-mined sheet surface, forming puparia. Flies of summer generation fly and lay eggs at the end of August. New mines appear in the beginning of September. Larvae of the 2nd generation do not harm significantly.
Economic significance.The pest populates rice and wild rice (Zizania latifolia (Griseb.) Stapf) in growth stages of full tillering and booting. Larvae destroy leaves by mining them, and young plants become greatly weakened. Plants are more often damaged at check dams. Control measures include insecticide treatments in the period of the pest oviposition.
Reference citations:Anonym. 2007. Agromyza oryzae. [G o o g l e's cache of http://www.hau1.edu.vn/CD_CSDL/RiceIPM/Html/Agromyza%20riceleafminer.htm as retrieved on 15 Feb 2007 22:03:24 GMT].
Klimanova N.K. 1971. On Agromyza oryzae Mun. In: Esipov A.G., ed. Collection of proceedings of Primorskii Agricultural Institute. V. 13 (1). Increase of efficiency agricultural production. Ulan-Ude, p. 37-40 (in Russian).
Klimanova N.K. 1975. To studying harmfulness of rice mining flies in Primorskii Territory. In: Kaz.min G.T., ed. Works of Far Eastern research institute of agriculture, v. 16(2). KHabarovsk: Dal.nevostochnyi NII sel.skogo khozyaistva, p. 38-45 (in Russian).
Mishchenko A.I. 1957. Insects - pests of agricultural plants in the Far East. Khabarovsk: Khabarovsk Publishing House, 198 p. (in Russian).
Narchuk E.P. 1980. Agromyizidae. In: Kopaneva L.M., ed. Key to harmful and useful insects and mites of grain cultures in the USSR. Leningrad: Kolos: 296-273 (in Russian).
Shchegolev V.N., ed. 1952. Keys to insects by their damage symptoms on cultural plants. Moscow & Leningrad: Sel.khozgiz, 604 p. (in Russian).
Tanasiichuk V.N., Zlobin V.V. 1981. Agromyzidae In: Narchuk E.P. & Tryapitsyn V.A., eds. Insects and mites . pests of agricultural plants. V. 4. Hymenoptera and Diptera. Leningrad: Nauka: 141-155 (in Russian).