بر جمعيت آن در مزارع نيشكر SCLIO FLAVIBARBIS M. )SCELIONIDAE( و اثر زنبور بارازيتوييد LOCUSTA MIGRATORIO L )ACRIDIDAE( بررسي بيولوژي ملخ

Investigation on Biology of Locusta Migratoria L. and Effects of the Parasitoid Scelio flavibarbis M. on the Grasshopper Population

The migratory locust Locusta migratoria L. is one of the most important acridids that causes heavy losses in sugarcane fields in Khuzestan. Because of its occasional damage, there has been less attention to this problem. To apply a safe control method, a study of biology and natural enemies is necessary. The biological studies were conducted under field and laboratory conditions in Khuzestan province in 1996 - 1999. The model of egg capsul distribution and effect of natural enemies were investigated. The biological studies showed that this pest had 3 generations under the field conditions. The population of the first generation was low and increased to overlap the second and third generations, which occurred in July and Agust. Hibernation occurred as egg, but the pest had 5 generations under laboratory conditions. It is concluded that the grasshopper has no obligate diapause. The model of egg capsul dispersion was clumped. The wasp Scelio flavibarbis was parasitized 44 - 52 % of the egg capsuls during 1996-1999. It is recommended that the wasp population in the field -must be supported by the use of careful cultivation operations.