A1, B1, C1 - L. trifolii . C2 - L. huidobrensis . A. Fly head showing background coloration. L. huidobrensis arrived in Israel resistant to conventional insecticides. Although L. huidobrensis is highly polyphagous, the two most important field crops affected are potatoes and celery.
Optimum catches are when yellow sticky traps are placed at, or slightly above, plant height.
Leaf samples are the best means to monitor larvae and the effects of insecticides. Each line represents the average number of leafminer adults from 2-6 fields that were monitored with yellow sticky traps Growers, responding to this peak of adult activity, first begin applying insecticides to control the leafminers and may make multiple applications until the end of the season in May or June. Trials were designed to reduce the number of insecticide applications by utilizing knowledge of the biology of the leafminer with the known mode of action of the available insecticides, thus treating the larval population that eventually will cause this peak of adult activity. The single application of these insecticides, 10-14 d before the anticipated adult peak, was intended to kill the larvae present in potato leaves. A dipterous leaf-miner on Cineraria , new to science.