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The relationship between susceptibility of different peach cultivars (cvs) to the Mediterranean fruit fly (medfly), Ceratitis capitata, and the volatile composition of ripe fruit of each cv has been investigated, since understanding the fruit-insect interaction mechanism is crucial for developing control strategies for such a pest. Volatile compounds were analyzed by SPME-GC-MS in three cvs highly susceptible to medfly attack (Fair Time, Flaminia, Sicilia Piatta), and in two less susceptible cvs (Percoca Romagnola 7 and Doctor Davis). Among the volatile compounds detected, 88 could be identified. The main differences found in the volatile composition of the cvs, concerned the relative abundance of esters. The least susceptible cvs, above all Percoca Romagnola 7, contained the higher amounts of hexenyl, hexyl, 3-methylbutyl, butyl and 2-methylpropyl esters; among these, some C6 derivatives detected, such as (Z)-3-hexenyl acetate, are known to act as priming agents, enhancing plant defence response to insects. Instead, a lower relative content of methyl esters, such as methyl hexanoate and methyl octanoate, known to act as medfly pheromone and attractant respectively, was found in the least susceptible cvs. © 2013 Elsevier Ltd. All rights reserved.

Apricot is one of the least sensitive stone fruit to aphids, but infestations of the mealy plum aphid may commercially damage fruits ready to harvest. Management of aphid infestations in organic orchard should also consider enhancing beneficial insects and limiting aphid species hard to control (wax-protected aphids). Green lacewings management through lures should represent a potential way to enhance the efficiency of this generalist predator against aphids. To evaluate this strategy, tests were performed in the frame of the P.O.N. BRIMET project (cod. MIUR 12929), between 2005 and 2007, in organic orchards in Southern Italy, near Nova Siri Marina (MT). Experimental design was used to assess attractiveness of a mixture of phenylacetaldehyde, methylsalicylate and acetic acid, and to evaluate the influence on oviposition of green lacewings. The experimental field was parcelled out into two similar lots, one of which with the lure in the central area. Trials on apricot were compared to the results obtained in peach orchards of the Centro di Ricerca per la Frutticoltura, near Rome. Results prove the attractiveness of this chemical lure towards Chrysoperla carnea (Stephens), but with a slight increase of oviposition in the apricot parcel with tested substances through the years. Only in 2007 we could measure an evident increase of oviposition on apricot trees. Better results were achieved on peach orchard where we could notice a more complex entomofauna. On apricot, the aphid presence can be assumed as a key factor for lacewings oviposition, and the presence of this lure as a secondary factor for a higher oviposition rate. Further basic researches on lacewings oviposition strategies are evidenced; moreover, an on-time application of lures upon the early symptoms of aphid infestations could represent the best application strategies to enhance natural population of lacewings on field.

Keywords. Neuroptera, Chrysopidae, Chrysoperla, green lacewings, attractant, phenylacetaldehyde Abstract. At five sites in Hungary and Italy, traps baited with phenylacetaldehyde caught significantly higher numbers (10 to 100 times more) of green lacewings than unbaited traps, which demonstrates that this compound is an attractant. Traps with three bait dispensers usually caught more than those with one dispenser, but the difference was significant only at two out of five test sites. There was no difference in the numbers caught by sticky delta and funnel traps baited with phenylacetaldehyde. However, funnel traps could be adapted to catch living green lacewings. The vast majority of the specimens belonged to the Chrysoperla carnea spe- cies complex. Ch. carnea sensu lato dominated the catches at all sites. At some sites 3-11% of the insects caught were Ch. lucasina Lacroix. Phenylacetaldehyde-baited traps were attractive to both sexes, but generally more females were caught than males. Funnel traps baited with three dispensers of phenylacetaldehyde caught green lacewing adults throughout the season in Hungary.

In field trapping tests, the catch of Chrysoperla carnea sensu lato (Neuroptera: Chrysopidae) increased when acetic acid was added to lures with phenylacetaldehyde. The addition of methyl salicylate to the binary mixture of phenylacetaldehyde plus acetic acid increased catches even further. The ternary blend proved to be more attractive than beta-caryophyllene, 2-phenylethanol, or 3-methyl eugenol (compounds previously described as attractants for chrysopids) on their own, and no influence on catches was recorded when these compounds were added as fourth components to the ternary blend. There were minimal changes in activity when (E)-cinnamaldehyde or methyl anthranylate (both evoking large responses from female or male antennae of C. carnea in this study) were added, although both compounds showed significant attraction on their own when compared to unbaited traps. In subtractive field bioassays with the ternary mixture, it appeared that the presence of either phenylacetaldehyde or methyl salicylate was important, whereas acetic acid was less so in the ternary mixture. The ternary blend attracted both female and male lacewings at sites in southern, central, and northern Europe. Possible applications of a synthetic attractant for lacewings are discussed.