北海道におけるムギキイロハモグリバエの発生生態と被害解析

抄録

In Hokkaido, the wheat leaf-sheath miner, Cerodontha (C.) denticornis (Panzer), may produce 3 generations in a year, with adult flies appearing June, August and September. Larvae initially make straight, slender leaf-mines toward the leaf base, then enter the leaf sheath, where the majority of infestations occur, followed by pupation. Mines on a leaf are visible only as very narrow white lines, and on leaf sheath as scattered inconspicuous white patches. Spring wheat is more susceptible than winter wheat to such infestation. Stems infested by first-generation larvae account for about a 2% loss in yield due to decreased grain weight. In 1996, a rather high 12% infestation of stems was seen in an unsprayed spring wheat field in Kunneppu. Neverthless, the estimated yield loss of 0.24% may be negligible.