Comparing the benefits between pesticides and ethylene treatments in reducing olive moth population numbers and damage

Abstract

Two treatments to control the olive pest Prays oleae Bern. were compared in a 2-year study at five different olivegrowing sites. In one treatment the pesticide dimethoate was sprayed, and in the second treatment ethylene was applied to olive trees in the form of ethrel (2-chloroethyl-phosphonic acid). In 2005 and 2006 the ethylene treatment provided a mean benefit of 340 Euros per hectare, whereas in the dimethoate treatment there were losses of 100 Euros per hectare. We conclude that treatments with dimethoate, the most widely used pesticide in southern Spain, are undesirable, reducing both the activity and killing efficiency of indigenous predators of P. oleae, mainly the green lacewing Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae), compared to control and ethylene-treated trees.

Monitoring and population characteristics of Prays oleae (Lepidoptera: Yponomeutidae) on different insecticidal treatments

“…Shehata et al (2003) showed that the lower threshold temperature (LTT) for total larval development was found to be 10.9 °C, registered in our study between April 10 th and 23 rd , and on May15th, 2014. The variable predator activity in this survey and that of Rosales et al (2008) was similar; i.e. : in our investigation, PA on dimethoate treatment were 63.3% and 73.2% on control plots, versus 60.9% and 72.7% respectively.…”

“…Flowers and fruits were examined under a stereo binocular microscope (Carl Zeiss, Oberkochen, Germany). The variable predator activity (PA%) has been determined according to Rosales et al (2006Rosales et al ( , 2008 and Sabouni et al (2008), i.e. the presence of predatory fauna of Chrysopidae were indirectly measured as the percentage of predation (ratio of destroyed eggs in the total number of observed eggs).…”