author(s)
Poornima V Matti, Lavanya DS and Tippannavar PS

abstract
White grub is an endemic pest and it is causing severe damage to the crop and reduction in cane yield. Usually adult emergence of H. serrata beetles is observed during the month of May-June beetles after the receipt of pre-monsoon showers, hence they are commonly known as May-June beetles. But a varied time of adult emergence in irrigated ecosystem was observed which is mainly attributed to growing of sugarcane in non traditional areas (rainfed area), wherein optimum soil moisture through protective irrigation during summer. Thus present investigation was carried out to know the adult emergence pattern of Holotrichia serrata in sugarcane irrigated ecosystem during 2018-20 at Bellad bagewadi, Hukkeri. Three years study revealed that, the emergence of H. serrata adults was commenced from February 7^th MSW (February) with weekly catches of 117.33 mean number of adults, which gradually increased from 8^th MSW and reached peak adult emergence during 10^th MSW (March) with 567.66 mean number of adults. At 14^th MSW (April), declined emergence of 94.66 mean number of adults was noticed and later 15^th MSW onwards negligible emergence was observed. However, during the period of present study emergence pattern of H. serrata adults under irrigated sugarcane ecosystem in overlapping stages of insect throughout the sugarcane growing season making the management of the pest more difficult. Our findings provide new insights of location specific management practices that can followed based on the adult emergence pattern of white grub. To determine spread and extent of the mean number of grub load per meter square at study location on other kharif crops was also recorded and results revealed that the grub load per meter square ranged highest of 10.33 in sugarcane during July month in study location. Whereas, highest of 3.56 no. grubs/m² on groundnut during July month, but least no. of grubs per square meter was recorded on soybean (0.78 no. grubs/m²).