FUNCTION OF A NEW TRAP FOR ROOT-DESTROYIN G MELOLONTHID BEETLES

A new trap for melolonthid scarabs, named CSAT-m, is described and stu died in order to understand how it works. Eight chemicals from pineapp le were evaluated as attractants with this trap, while ripe pineapple was used as control. Temperature of air inside and outside the CSAT-m trap was recorded during the study. The occurrence of a full solar ecl ipse in the area provided an opportunity to study these temperature di fferentials, observing a 5 degrees C difference in a short time betwee n inside and outside the trap. Methyl acetate and ethyl acetate were t he most volatile of the tested compounds; their use resulted in the mo st insects captured, specially the melonthids Cotinis mutabilis, Cyclo cephalla guttata and Phyllophaga spp. These beetles are important pest s because the adults feed on economic fruit and their larvae damage th e roots of crops. Highest numbers of insects were attracted and captur ed when these chemicals were used during sunny days, when more chemica ls were dispersed. Trap efficiency should be considered in terms of le vel of lure dispersion, not just in terms of time of operation.