Studying on possibility of simultaneous control of olive psyllid, Euphyllura straminea Loginova and olive soft scale, Parlatoria oleae Colvee in Tarom region of Zanjan province

Olive soft scales Euphyllura straminea Loginova and olive psyllid Euphyllura straminea Loginova are important pests of olive trees in Tarom region of Zanjan province. The use of dormant oil in winter to control of these pests is recommended based on research done in the past years. Due to reports of inefficiency of dormant oil for the control of olive soft scales and olive psyllid, this project was conducted to evaluate the results of previous findings as well as to evaluate the possibility of simultaneous control olive soft scales and olive psyllid. Experiment was carried out based on RCBD with split plot arrangement in four replications. Main factor was time of application in three levels:  1- winter 2- winter + spring and 3- spring and sub-factor was type of spraying solution in four levels:  1- dormant oil, 2- mixture of oil (1.5%) + chlorpyrifos (0.2%), 3- chlorpyrifos (0.2%), and 4- control treatment. Sampling was performed once before and 3 times including 2, 3 and 4 weeks after treatments and subsequently number of alive and dead specimens were counted. Based on results, the mixture of oil + chlorpyrifos caused 94.25 and 100% mortality and chlorpyrifos caused 85.75 and 100% mortality on olive soft scales and olive psyllid respectively in winter (preferably the second half of March in Tarom climatic conditions).