بررسی بیولوژی و شناسایی دشمنان طبیعی سرخرطومی برگخوار صنوبر

Platymycterus marmoratus Fst. (Col.: Curculionidae) is the important pest of poplar trees in Guilan province. High density of adults were observed on different poplar clones in the last years. Biological characteristics of this pest were studied during 2003-2005 in poplar nurseries in Safrabasteh research station. Based on the results, leaf weevil adults appeared from mid May till late October to mid November, with the peak of population in mid July. The over position started one day after mating . Incubation period of the eggs was 5-7 days . Adults feed were edge of leaves and at females were more than males , but in over position 'period , feeding decreased and then stopped two days before death. The average longevity in feeding condition and without it were 3O=J:23 and 12.5:1.5 days for males and 28.5:25 and 14.5:1.5 days for females respectively . This pest has one generation per year and probably, over winter as pupa in Guilan province. Two species of predator bugs include Coranus sp. and Rhinocoris sp. were feeding on adults. Key word: Platymycterus marmoratus Fst., poplar, biology, natural enemies, Guilan province