Abstract
The bionomics of a major pest beetle of the shiitake mushroom was studied by means of mushrooms' bait trapping and outdoor rearing. D. japonica hibernates in adults and larvae. Most larvae die during hibernation. The adults lay eggs in the mushrooms from March to May and die. The 1 st adults emerge in July and fly to the mushrooms. They eat the mushrooms but do not lay eggs. Then they leave the mushrooms during summer. They make 2 nd flight to the mushrooms in late October and lay eggs. Then they go into hibernation with their progeny larvae. So D. japonica is supposed dominantly to be univoltine.
