he present work was carried out to describe a new innovation of a simple detachable olfactometer for measuring the olfactory responses of fruit flies to different odors. Such device may be useful to discover the efficiency of current attractive or repellent odors or new odors that could be used for controlling fruit flies in fields. It could save effort, time and money required to investigate any new attractive or repellent material prior usage in the field Many experiments were conducted to standardize this device using the standard attractive material " Buminal ". These trials included determination of optimum concentration of test odor, optimum dose to test, velocity of air flow inside device, optimum number of flies that could be used in every test, optimum light intensity, best exposure time to test material and relationship between response of flies to test odor and temperature.

Two experimental designs were carried out at Fayoum Governorate during mature fruit seasons of 2006 and 2007 to establish different levels of infestation on the economic injury level of the Mediterranean fruit-fly (Medfly) Ceratitis capitata (Wied.). In the first trial, four mandarin trees at different levels of infestation were surrounded by muslin cages constructed by wooden frames. Sticky traps baited with trimedlure were hung on each tree for evaluating adult fly density and the relationship between trap catch and infestation percent, total of living stages and crop loss. The second trial was carried out to establish a range of infestation levels across experimental field plots of mandarin using different insecticide treatments to evaluate the relationship between C. capitata density and the abovementioned parameters. High levels of C. capitata adults in trap catch were associated with significant reductions in fruit yield. The loss in mandarin yield was evaluated at different levels of infestation. High yield loss was obtained (903$/feddan) in mandarin plots when no control practices were applied.

Field experiments were conducted to evaluate the efficiency of Makkar and El-Abbassi plastic trap loaded with four attractant sachets against the Mediterranean fruit fly Ceratitis capitata (Wied). Trials were carried out in two different locations,