BIOLOGICAL AND MICROBIAL CONTROL Suitability of the Pest–Plant System Tuta absoluta (Lepidoptera: Gelechiidae)–Tomato for Trichogramma (Hymenoptera: Trichogrammatidae) Parasitoids and Insights for Biological Control ANAI ¨ S CHAILLEUX, 1,2,3 ANTONIO BIONDI, 1,4 PENG HAN, 1 ELISABETH TABONE, 5 AND NICOLAS DESNEUX 1 J. Econ. Entomol. 106(6): 2310Ð2321 (2013); DOI: http://dx.doi.org/10.1603/EC13092 ABSTRACT The South American tomato leafminer, Tuta absoluta Meyrick (Lepidoptera: Gelechii- dae), is a major pest that has recently invaded Afro-Eurasia. Biological control, especially by Tricho- gramma parasitoids, is considered to be promising as a management tool for this pest. However, further development of Trichogramma-based biocontrol strategies would beneÞt from assessing the impact of released parasitoid offspring on the pest. Under laboratory conditions, we 1) compared the parasitism of Þve Trichogramma species-strains on the pestÐplant system T. absolutaÐtomato, and 2) assessed various biological traits of parasitoids, mass-reared on a factitious host (Ephestia kuehniella Zeller), when developing on T. absoluta. In addition, we evaluated the overall efÞciency of two speciÞc Trichogramma species when released under greenhouse conditions in combination with a common natural enemy in tomato crop, the predator Macrolophus pygmaeus Rambur. Parasitoids emerging from T. absoluta on tomato showed lower parasitism rates and poor biological traits, for example, wing deformations, reduced longevity, when compared with the control reared on the factitious host. Under greenhouse conditions, the parasitoids that developed on T. absoluta after initial releases contributed little to biological control of T. absoluta, and parasitism tended to be lower when the predator was present. However, a slightly higher T. absoluta control level was achieved by combining the predator and release of the parasitoid Trichogramma achaeae Nagaraja and Nagarkatti. This study shows that Trichogramma parasitoids may not build up populations on the T. absolutaÐtomato system, but that Trichogramma parasitoids can be used in combination with M. pygmaeus to enhance biological control of the pest in tomato crops. KEY WORDS Þtness, generalist predator, invasive species, inundative release, mass-rearing The South American tomato leafminer, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is one of the most devastating tomato pests in South America (Gon- tijo et al. 2013). The pest has recently invaded and spread in the Afro-Eurasian continent, and in few years has become a major pest in tomato crops (Desneux et al. 2010, 2011a). Appearance of T. ab- soluta has led to extensive insecticide use by tomato growers, potentially causing a multitude of undesired side effects on nontarget organisms (Desneux et al. 2007; Arno ´ and Gabarra 2011; Biondi et al. 2012, 2013a). Among possible management methods cur- rently studied (Amer et al. 2012, Cagnotti et al. 2012, Caparros Megido et al. 2012, Cocco et al. 2013), bio- logical control is considered for the development of environmentally and economically sound pest man- agement tools for this pest in Europe (Desneux et al. 2010, Zappala ` et al. 2013). Agricultural pests are largely controlled via topÐ down inßuences of natural enemies in a wide range of agro-ecosystems (van Dri- esche and Bellows 1996, Hawkins et al. 1997, Symond- son et al. 2002, Lu et al. 2012). However, their use as biocontrol agents, either through augmentation or conservation biological control, is often slowed down because their effectiveness in the Þeld is difÞcult to predict. Parasitoids belonging to the Trichogramma genus (Hymenoptera: Trichogrammatidae) are generalist egg parasitoids, mainly of Lepidoptera. They are fre- quently used in biological control programs, notably through inundative releases (Smith 1996, Pintureau 2009, Mills 2010). In addition, inoculative releases of Trichogrammatids have been tested on agricultural pests in various crops (Thomson et al. 2003, Hoffmann et al. 2006, Mills 2010). In South America, T. absoluta is parasitized by Trichogramma pretiosum Riley under laboratory conditions (Pratissoli and Parra 2000), and 1 French National Institute for Agricultural Research (INRA), ISA, 400 Route des Chappes, 06903 SophiaÐAntipolis, France. 2 InVivo AgroSolutions, 83 avenue de la Grande Arme ´ e, 75782 Paris, France. 3 Corresponding author, e-mail: chailleux.anais@gmail.com. 4 Department of Agri-Food and Environmental Systems Manage- ment, University of Catania, Via Santa SoÞa 100, 95123 Catania, Italy. 5 French National Institute for Agricultural Research (INRA), UEFM, 90 Chemin Gustave Raymond, 06160 Antibes, France. 0022-0493/13/2310Ð2321$04.00/0  2013 Entomological Society of America