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The tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) represents a global threat to commercial tomato (Solanum lycopersicum L.) production, both in open field and greenhouse. Native to South America, it spread over the Mediterranean Basin, Europe, Africa and part of Asia in only 12 years, and currently it is reported in over 80 countries. Biological control is one of the options for its control and a large number of natural enemies has been reported in association with the pest, both in the areas of origin and of introduction. The egg parasitoid Trichogramma pretiosum, in South America, and the mirid predators Macrolophus pygmaeus and Nesidiocoris tenuis, in Europe and the Mediterranean basin, are used as commercial biocontrol agents. Even if several natural enemies might be promising candidates for biocontrol, their potential role in quantitative pest reduction has been seldom established under practical tomato production conditions. Since climatic suitability indices predict a high probability for continued invasion by T. absoluta, mainly in China and the USA, there is an urgent need for new control options. In order to minimise the use of broad spectrum insecticides, biocontrol techniques should be considered. As tomato is produced seasonally, augmentative biocontrol seems to be the most effective control option, but pest reduction might be optimised by adding conservation biocontrol, and by combining biocontrol within IPM programmes. Here, an overview of predators and parasitoids of T. absoluta in South American and Euro-Mediterranean regions, and their biological control efficacy under laboratory, semi-field and field conditions is provided. Fil: Ferracini, Chiara. Università di Torino; Italia Fil: Bueno Vanda H. P.. Universidad Federal de Lavras; Brasil Fil: Dindo, María Luisa. Universidad de Bologna; Italia Fil: Ingegno, Bárbara L.. Università di Torino; Italia Fil: Luna, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina. Universidad Nacional de San Antonio de Areco; Argentina Fil: Salas Gervassio, Nadia Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina. Universidad Nacional de San Antonio de Areco; Argentina Fil: Sanchez, Norma Elba. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina Fil: Siscaro, Gaetano. Università Degli Studi Di Catania; Italia Fil: Van Lenteren, Joop C.. University of Agriculture Wageningen; Países Bajos. Universidad Federal de Lavras; Brasil Fil: Zappalà, Lucia. Università Degli Studi Di Catania; Italia Fil: Tavella, Luciana. Università di Torino; Italia

Organic avocado (Persea americana Mill. (Lauraceae) farming is a growing industry in eastern Sicily, and in this environment Protopulvinaria pyriformis (Cockerell) (Hemiptera: Coccidae) is a key pest. Biological control strategies against this invasive scale are thus crucial for the sustainability of this cropping system. A field trial was performed to record the natural enemy complex in early autumn, and for comparing the efficacy of a paraffinic oil application (Biolid E® at 2L/ha), of the release of adults (1/m2) of the predator Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae), and of their combined application, i. e. oil spray and after one week predator release. In the pretreatment sampling a high proportion of ovipositing female, 38. 64% of the entire population, was recorded. The natural parasitoid community of P. pyriformis consisted of two primary parasitoids and one facultative hyperparasitoid species. Metaphycus helvolus (Compere) (Hymenoptera: Encyrtidae) accounted for 81% of the parasitoids recovered; Microterys nietneri (Motschulski) (Hymenoptera: Encyrtidae) for 8%, and the secondary parasitoid Pachyneuron muscarum (L. ) (Hymenoptera: Pteromalidae) for 11%. The mean percentage of parasitism recorded was 2. 45%, however, an encapsulation rate of 1. 78% was also observed. Adults and larvae of generalist predators belonging to the genera Scymnus spp, Exochomus spp. (Coleoptera: Coccinellidae) and larvae of Chrysopa spp. (Neuroptera: Chrysopidae) were also noticed actively feeding on immature stages of the soft scale. The number of live scales (N2-oviposting females) was reduced by 54. 16, 55. 73 and 19. 58 % following the oil application, the oil plus predator release and predator alone, respectively. While, in the control plots the number of live scales increased by 23. 4%, and no changes in the presence of natural enemies was recorded in the sprayed plots. The recorded data suggest that any pesticide application should take into account and thus respect the activity of the rich natural enemy assemblage. In addition, artificial releases of C. montrouzieri were not able to effectively control the scale population., Entomologica, V. 47 (2016)

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The South American tomato pinworm, Tuta absoluta (Meyrick), is one of the major pests of tomato crop. Since its detection in the Mediterranean basin, it has been commonly controlled using chemical insecticides. However, inoculation and conservation of predatory mirids, integrated with sprays of selective insecticides, has been demonstrated to be a cost-effective strategy for controlling this pest. In this work, we tested the efficacy of two sulphur formulations, dustable and wettable powder, for controlling T. absoluta on tomato under greenhouse and open-field conditions. In addition, the side effects of both sulphur formulations on the predator, Nesidiocoris tenuis (Reuter), were evaluated under laboratory conditions. Dustable sulphur, applied weekly on tomato seedlings artificially infested with T. absoluta in greenhouse conditions, significantly reduced the infestation levels and was demonstrated to have a repellent effect on oviposition. Wettable sulphur was not effective for controlling T. absoluta populations in both greenhouse and open-field experim ents. In the side effect trials conducted with N. tenuis, only dustable sulphur resulted in being moderately harmful as a fresh residue and slightly harmful as a 7-day-old residue; no effects were recorded exposing the predator to 14-day-old sulphur residues. In contrast, wettable sulphur was classified as harmless to N. tenuis. Our results suggest that the use of sulphur, especially as dustable powder, could be considered as a tool in T. absoluta management strategies, although its side effects on N. tenuis should be taken into account. The implications of these results for the use of sulphur formulations in pest and disease management programmes in tomato crops are discussed.