IMPACT OF DIFFERENT MAIZE CULTIVARS ON PRE HARVEST INFESTATION BY SITOTROGA CEREALELLA (OLIVIER) (LEPIDOPTERA: GELECHIIDAE)

Abstract

This experiment was carried out in the Maize research station at Vaagarai during the year of 2013-2014 for assessing the “Effect of different cultivars on the pre harvest infestation by Sitotroga cerealella”. A total of 41 samples collected from the maize field. They were of four types: extra early, early, medium and late maturing hybrids. Among the 41 samples, 14 are extra early, nine are early, nine samples are medium and 9 are late maturing hybrids. From all the samples, adult emergence was recorded for every day up to eight weeks. Adult emergence was recorded in all the four samples types. There is no relation between type of hybrids and sowing date and harvesting time. But compared to the late and extra early samples types, the early and medium types were infested with less percentage of adults. The possible reasons for the field incidence may be due to Harvesting of crop in phased manner because of non synchronisation in grain maturation in a particular place, which in turn is due to staggered sowing. So the infestation from matured crop is carried over to the late maturing crop in the field itself, In double and triple cropped areas, its field incidence may be prolonged because of the continuous availability of host as at Vaagarai, In single and double cropped areas, during the off season it may survive on the alternate hosts like rice, sorghum, pearl millet and barnyard millet, Migrations of S. cerealella from the nearby the godown to the field and he variations in the level of infestation might be due to variation in cropping systems, seasons, time of harvest, availability of alternate hosts and debris.