Journal of Pest Science (2013) 86, 533-541

Anaïs Chailleux, Philippe Bearez, Jeannine Pizzol, Edwige Amiens-Desneux, Ricardo Ramirez-Romero and Nicolas Desneux (2013)
Potential for combined use of parasitoids and generalist predators for biological control of the key invasive tomato pest Tuta absoluta
Journal of Pest Science 86 (3), 533-541
Abstract: The tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) has recently invaded Mediterranean countries and is a major pest in tomato crops. Trichogrammatid oophagous parasitoids have shown promising potential for controlling the pest before the yield decreases in the greenhouse. In protected tomato crops (greenhouse), mirid predators are commonly used for biological control of whiteflies and they also prey on T. absoluta. These predators do not attack Trichogramma adults but they may partially decrease the overall impact of parasitoids on T. absoluta if intraguild predation (IGP) occurs on parasitized eggs. Under laboratory conditions, we tested if the mirid predator Macrolophus pygmaeus shows preference between parasitized and unparasitized T. absoluta eggs. We also tested if the predator reduces the number of parasitized eggs on caged tomato plants (microcosms) and assessed the efficacy of natural enemies used alone or together in limiting T. absoluta populations. We found that IGP is inflicted on the parasitoid Trichogramma achaeae by M. pygmaeus and that the risk of IGP depends on the developmental stage of T. achaeae inside the egg because the larva is at risk mostly early in its development (when parasitized egg is still yellow). In addition, we observed that non-consumptive events, likely probing of the predator on parasitized eggs, may induce mortality in parasitoid offspring without actual feeding on parasitized eggs. However, both IGP and non-consumptive events decreased when the predator was not confined with parasitized eggs in small arenas. Despite negative effects of the predator to the parasitoid, results demonstrate that adding Trichogramma parasitoids may significantly increase the level of control of the pest over what could be attained when only the mirid predator M. pygmaeus is present on tomato. Implications of results are discussed regarding potential of these natural enemies for biological control of T. absoluta in greenhouse tomato crops.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Nicolas Desneux, Ricardo Ramirez-Romero

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
application technology

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Phthorimaea absoluta	Tomato (Solanum lycopersicum)
Macrolophus pygmaeus (predator)	Phthorimaea absoluta	Tomato (Solanum lycopersicum)
Trichogramma achaeae (parasitoid)	Phthorimaea absoluta	Tomato (Solanum lycopersicum)