K.L. JEENGAR*, A.K. SRIVASTAVA AND O.P. AMETA

Studies on the seasonal incidence of the insect pests of maize were conducted during 2003-2004 at the Krishi Vigyan Kendra (MPUAT, Udaipur), Bhilwara, Rajasthan. The stem borer [Chilo partellus (Swinhoe)], the armyworm (Mythimna separata Walker), maize aphid (Rhopalosiphum maidis Fitch) and the kharif grasshopper (Hieroglyphus nigrorepletus Bolivar) were recorded as the major pests. The infestation of stem borer began in the last week of July (30th standard meteorological week) and reached to its peak in second week of August (32nd standard meteorological week), that of army worm began in the second week of August (32nd standard meteorological week) and reached to its peak in last week of August (35th standard meteorological week). The infestation of aphid and grasshopper began in the first week of August (31st standard meteorological week). The peak of aphid population was recorded during the 36th standard meteorological week in either year. The kharif grasshoppers were in significant numbers during 34th and 35th standard meteorological weeks. The abiotic factors of the environment did not show any significant influence on the major insect pests.