POPULATION BUILT UP OF SUGARCANE WOOLLY APHID, CERATOVACUNA LANIGERA IN MAHARASHTRA AND ITS RELATION WITH ESTABLISHMENT OF PREDATOR, DIPHA APHIDIVORA

摘要

The survey of population built up of sugarcane woolly aphid (SWA) and establishment of its predator, D. aphidivora was taken in three agro-climatic zones (South, Central and Northeast) of Maharashtra to know the subsequent relation of the predator with the incidence of SWA in sugarcane during 2006-07 and 2007-08. The survey result showed that in all the three zones, the maximum SWA population of 89.43 nymphs and adults/2.5 cm~2 was recorded in Northeast Maharashtra in December 2006 while predator development was maximum of 2.42 larva and or cocoon/leaf in Central Maharashtra in October 2006.In South Maharashtra, the SWA population hardly moved above 25 nymphs and adults/2.5 cm~2. A better establishment of predator in 2006-07 resulted in low population built up of SWA in 2007-08 in Central Maharashtra. The heavy SWA incidence coincided with low predator development in Northeast Maharashtra and therefore augmentative release of predators for the coming year is necessary for the better establishment of the predators. This programme will be helpful in the management of SWA in Northeast Maharashtra.In all the agro-climatic zones, SWA population start in July, increase in August and reduce in the month of October due to increase in population of D. aphidivora. However, SWA population again increases in December as establishment ofD. aphidivora is hampered due to cold weather. In the summer months of April to June, SWA population remains absent.