author(s)
Wiem Hached, Hajer Sahraoui, Achref Blel and Kaouthar Lebdi Grissa

abstract
The carob moth, Ectomyelois ceratoniae (Lepidoptera: pyralidae) is a polyphageous pest that ingest several important economic host plants in Tunisia such as dates and pomegranates. During the latest years, damages on citrus fruits were reported in Tunisian citrus orchards. As this pyralid has an endophytic behavior which makes its control with insecticides inefficient, biological control could be a crucial tool in the fight against it. For that reason, our study was conducted to investigate the efficacy of an oophagous parasitoid, Trichogramma cacoeciae, for biological control of this pest thanks to three releases conducted in a Tunisian citrus field. Results showed a significant difference between laboratory and field conditions for both emergence and parasitism rates of Trichogramma cacoeciae. Moreover, a significant difference in the infestation rates at harvest between the control and the two treated blocks after T. cacoeciae releases in the citrus field was obtained, thus the efficacy of this parasitoid was about 44.5% at harvest. Several factors that affect T. cacoeciae efficacy in the citrus field were discussed. However, despite the infestation level decrease in the treated blocks, this rate was not sufficient to limit economic losses suggesting that, this biological agent could be used as a part of an integrated pest management program of this pest.