Cost–benefit analysis of pistachio twig borer, Kermania pistaciella Amsel (Lepidoptera: Oinophylidae) chemical control

Abstract

Pistachio twig borer is a major pest of pistachio orchards in Iran. In order to reduce the pest damage, a conventional pesticide application is used annually. However, it is not known how much damage is caused by this pest. To determine the potential damage of Kermania pistaciella, and to qualify how efficient chemical control is in reduction of the pest damage, an experiment was conducted at two pistachio orchards in Kerman province (Kerman and Sirjan). A randomised complete block design, with two treatments – chemical control (a mixture of endosulfan EC 35 and volk, 2.5:5 l/ha) and check with five replications were performed. To estimate the pest damage, 25 randomly selected trees were chosen then the total fruit bunches of each tree were checked for infestation to the pest. The infestation percentage in Kerman was greater than that for Sirjan region (10.3% vs. 5.9%). When treatments were compared, the infestation rate of check plots were significantly more in comparison of treated plots in Kerman (10.3% vs. 3.6%); however, there was no significant difference between treatments in Sirjan (5.9% vs. 3.1%). The efficiency of chemical control was 60.7% and 48.7% in Kerman and Sirjan, respectively. There was not definite correlation between the number of capture and the infestation rate (r = 0.442). Cost–benefit ratio calculation was less than 1 (Kerman (−0.89) and Sirjan (−0.94)) and it means that chemical control at this damage percentage is not economic.

Keywords:

• chemical control
• Iran
• Kerman
• Kermania pistaciella
• pistachio

Acknowledgements

This project was funded by the Iranian Research Institute of Plant Protection. The authors would like to thank their colleagues in the Department of Plant Protection of Agricultural and Natural Resource Research Centre of Kerman province.