Mythimna loreyi (Duponchel)
(Also known as Acantholeucania loreyi (Duponchel), Hyphilare loreyi (Duponchel) and Leucania loreyi (Duponchel).
Common name: Loreyi leafworm, rice armyworm.
Systematic position: Insecta, Holometabola, Lepidoptera, Noctuidae.
Geographical distribution: Cosmopolitan, except in cold regions.
Host plants: Various Poaceae (Graminae), including wheat, barley, maize (corn) and sorghum.
Morphology: The adults are about 15-20 mm in length, forewings pale-brown, with a small dark spot in the middle, hindwings whitish, with pale-brown veins. The legs are also brown. The larvae are grey–brown with 2 dark and 2 pale longitudinal stripes, about 35 mm long.
Life history: The adults are nocturnal, producing >1000 eggs/female that are placed on host leaf sheaths and stems. The emerging larvae skeletonize and devour the leaves, pupating in the soil. The adults live for 2-3 weeks and raise several annual generations.
Economic importance: This armyworm is an occasional serious pest of many gramineous crops. These include wheat and barley in winter, maize and sorghum in summer, whose yields are reduced.
Management
Biological control: Several parasitoids attack the pest in Turkey. Of these Cotesia ruficrus was the most abundant, with almost 70% parasitization rates. In addition, in Turkey M. loreyi was also parasitized by 4 tachinids, which together killed about 18% of the pest’s population. Other control agents include a strain of Bacillus thuringiensis that was isolated from dead M. loreyi larvae in Spain and a new entomophagenic virus which was discovered in Egypt.
References
Fédière, G., El-Sheikh, M.A., Abol-Ela, S., Salah, M., Masri, M. and Veyrunes, J.-C. 1995. Isolation of a new densonucleosis virus from Mythimna loreyi Dup. (Lepidoptera: Noctuidae) in Egypt. Bulletin of the Faculty of Agriculture, University of Cairo 46: 693-702.
Hirai, K. and Santa, H. 1983. Comparative physio-ecological studies on the armyworms, Pseudaletia separata Walker and Leucania loreyi Duponchel (Lepidoptera: Noctuidae). Bulletin of the Chugoku National Agricultural Experiment Station, E 21: 55-101.
Kara, K, Gözüaçık,C. and Mart, C. 2007. Note: Tachinid parasitoids (Diptera: Tachinidae) of Mythimna (Acantholeucania) loreyi in the southeast Anatolian region of Turkey. Phytoparasitica 35: 136-139.
Porcar, M. and Caballero, P. 2000. Molecular and insecticidal characterization of a Bacillus thuringiensis strain isolated during a natural epizootic. Journal of Applied Microbiology 89: 309-316.
Sertkaya, E. and Bayram, A. 2005. Parasitoid community of the loreyi leaf worm Mythimna (Acantholeucania) loreyi: Novel host — parasitoid associations and their efficiency in the eastern Mediterranean region of Turkey. Phytoparasitica 33:441–449.