نوع مقاله : مقاله پژوهشی
عنوان مقاله [English]
The Sunn pest is the major insect problem of cereal, especially wheat and barley in Iran. Chemical control is the most effective and frequently used control method against sunn pest. Most treatments to control of this pest are done when adults and nymphs are in fields with the highest number. It means chemical materials are used against overwintering adults and nymphs. For several years, two commercially insecticides, deltamethrin and fenitrothion, have used for achieving control of sunn pest were. A new project was designated to evaluate efficiency of a newly introduced chemical insecticide to control the pest. Insecticides were tested in two locations in Ghazvin and Kermanshah provinces. For comparison, two formulations of Deltamethrin, Deltamethrin EC 2.5%, Deltamethrin SC 2.5% , a formulation of Fenitrothion,Fenitrothion EC50%andlambda cyhalothrin ( Karate zone CS100® ) were tested based on a randomized complete block design with four replications. All chemicals were tested against both 2nd nymphal stages and overwintering adults. Two concentration ofDeltamethrin SC 2.5%, 250 and 300 ml/ha, and two of Karate zone CS100, 75 and 100 ml/ha, were tested. Average mortality percent of overwintered adults in two locations, were 84.94, 88.2, 87.93, 92.2, 90.65, 93.11 respectively and for nymphal stages 85.92, 92.18, 95.37, 90.35, 92.14 and 94.32 respectively. The results of the experiment showed no statistically significant difference between treatments and all insecticides can be effective in reducing the percentage of quantitative and qualitative damage. The efficiency of treatment by two insecticides, Deltamethrin SC 2.5% and Karate zone CS100 for 20 days after spraying was more than 70 percent so these insecticides are recommended to be included in a pesticide rotation with others for reducing the probability of resistance biotype formation in sunn pest.