Evaluation of some insecticides to control the potato tuberworms Phathorimaea operculella (Zeller) on tomato crop in Al-Kharj province.

The purpose of present study is to evaluate and to know the efficiency of some insecticides used to control the potato tuberworms Phathorimaea operculella (Zeller), and to know the effect of infestation on the yield of tomato, and to record the effect of the mis-use of insecticides in traditional farms. The best insecticide tested was cypermethrin , which reduced infestation by 85.5%, then Beta-cyfluthrin (67.3%). The results indicate the decrease in the efficiency of these insecticides. There was a similarity of the results of most of these insecticides , except for cypermethrin and Beta-cyfluthrin. Also, the results indicate the presence of resistance among the population of this insect as a result of the mis-use of insecticides in some traditional farms