• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.165-168
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• 2007

This experiment was conducted to investigate population dynamics of white grubs and its damages in sweet potato fields. There were three species of white grubs that fed on the roots of sweet potato in Honam area. Among them, Holofrichia parallela was a major insect pest. Damage rate of sweet potato by white grubs were about 2 to 40% differed with regions. In some region where it was severe the damage rate of sweet potato was about 80% or more. H. parallela overwintered as a late 3rd instar larvae in soil from late October to late-June, and the survival rate of them was 92%. The occurrence pattern of H. parallela larvae varied in different seasons. In sweet potato field, H. parallela larvae populations started being observed during late-July to mid.-August. The damage by the grub began to occur late-August in field and lasted to the harvest time.