Nontarget Host Risk Assessment of the Egg Parasitoid Trichogrammatoidea cryptophlebiae (Hymenoptera: Trichogrammatidae) for Classical Biological Control of the False Codling Moth (Lepidoptera: Tortricidae) in Israel.

Abstract

The false codling moth Thaumatotibia leucotreta (Meyrick), is an invasive species in Israel. In order to carry out a classical biological control program, the African egg parasitoid Trichogrammatoidea cryptophlebiae (Nagaraja) was recently introduced into Israel, and nontarget host risk assessment was performed as required. In no-choice tests we determined that T. cryptophlebiae was unable to develop in eggs of four nontarget Lepidopteran species: Pectinophora gossypiella (Saunders), Spodoptora littoralis (Boisduval), Ephestia kuehniella (Zeller), and Belenois aurota (Fabricius). Conversely, it developed in three Lepidopteran species eggs of the Tortricidae family: Cydia pomonella (Linnaeus), Lobesia botrana (Denis and Schiffermüller), and Epiblema strenuana (Walker). Epiblema strenuana eggs showed the lowest parasitism level among all tested moth eggs of the Tortricidae family. The progeny production of parasitized false codling moth eggs was similar to that of C. pomonella eggs, but smaller than that of L. botrana eggs. However, moth egg and parasitoid clutch sizes were smallest on L. botrana eggs and largest on C. pomonella eggs. In choice bioassays, T. cryptophlebiae significantly preferred to parasitize T. leucotreta eggs over the eggs of C. pomonella, L. botrana, and E. strenuana. Moreover, the choice of T. leucotreta eggs over the eggs of L. botrana was not affected by the parasitoids' rearing histories. Our data support the assumption that T. cryptophlebiae develops only in moth species of the Tortricidae family. Thus, the risk that it may attack nontarget species is low.