The sexual calling incidence of wild and mass‐reared Mediterranean fruit fly males, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), was studied at 25 °C and a photophase of 14 h starting at 0600 h. Wild males fed on yeast hydrolysate and sugar attained sexual maturity earlier and exhibited higher calling activity than males fed on sugar alone. In both sugar and yeast hydrolysate‐fed wild males, calling levels were high during the first hours of the photophase, declined at 0900–1000 h, then increased again reaching high levels between 1200 and 1500 h, and finally declined and ceased after 1600 h. Food deprivation for 8 h or more caused a significantly lower frequency of calling. Irradiated (sterile) and unirradiated mass‐reared males fed on either sugar and yeast or sugar alone did not differ in the age of attaining sexual maturity (maximum levels of calling occurred about 8 days earlier than in the wild males). However, irradiated males fed on sugar called less frequently than males in the other treatments of mass‐reared males. The daily rhythm of calling in protein and sugar‐fed irradiated males differed somewhat from that of wild males. Calling was recorded at high levels from the beginning of the photophase until 1300 h without any decrease at 0900–1000 h. It then decreased to very low levels from 1500–1800 h and increased slightly at 1900 h. These findings are discussed in relation to the mating behavior of the fly and to the effectiveness of released sterile males in Sterile Insect Technique programs.

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The response of wild Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) males to orange peel chemicals and their effect in mating competitiveness of males exposed to these chemicals was studied in the laboratory (25±2 °C, 65±5%, r.h.). Males were attracted, landed, and arrested on ripe oranges that were superficially wounded in the flavedo region of the peel, and fed on the wounds. Exposure to wounded oranges conferred to males a mating advantage over unexposed males. In flies of 1 to 10 days of age, this advantage was independent of the age of the flies during exposure and lasted at least 10 days following exposure. Twenty‐four hours of exposure ensured this effect. Exposure to intact oranges, or to wounded oranges covered with a wire‐screen, which allowed olfactory response and landing on the screen but not direct contact with the fruit, did not confer any mating advantage. Apparently, males required direct contact with wounded oranges in order to increase their mating competitiveness. It is suggested that the acquisition of certain substances of the flavedo, most probably through their ingestion, is responsible for the observed phenomenon. Our findings are discussed in relation to the sexual behaviour of this fly. Implications of these findings for the enhancement of the mating competitiveness of released sterile males and of the effectiveness of the Sterile Insect Technique programs are discussed as well.

The Dipteran family Tephritidae (true fruit flies) comprises more than 5000 species classified in 500 genera distributed worldwide. Tephritidae include devastating agricultural pests and highly invasive species whose spread is currently facilitated by globalization, international trade and human mobility. The ability to identify and exploit a wide range of host plants for oviposition, as well as effective and diversified reproductive strategies, are among the key features supporting tephritid biological success. Intraspecific communication involves the exchange of a complex set of sensory cues that are species- and sex-specific. Chemical signals, which are standing out in tephritid communication, comprise long-distance pheromones emitted by one or both sexes, cuticular hydrocarbons with limited volatility deposited on the surrounding substrate or on the insect body regulating medium- to short-distance communication, and host-marking compounds deposited on the fruit after oviposition. In this review, the current knowledge on tephritid chemical communication was analysed with a special emphasis on fruit fly pest species belonging to the Anastrepha, Bactrocera, Ceratitis, and Rhagoletis genera. The multidisciplinary approaches adopted for characterising tephritid semiochemicals, and the real-world applications and challenges for Integrated Pest Management (IPM) and biological control strategies are critically discussed. Future perspectives for targeted research on fruit fly chemical communication are highlighted.

Trapping experiments were conducted during the period of flight activity of the cherry fruit fly Rhagoletis cerasi L. in the area of Thessaloniki, northern Greece, during the years 1993-1997 to test several traps alone and in combination with different food attractants. Yellow sticky-coated visual traps were more effective than McPhail-type traps baited with different food attractants. Of the visual traps, the most effective was the yellow Rebell trap. The Rebell trap, provided with a dispenser containing a slow release formulation of ammonium acetate attached to the lower part of the trap, was found to be the most effective of all treatments tested, capturing approximately 50% more R. cerasi flies than the Rebell trap without any attractant. Ammonium carbonate dispensers did not increase the performance of Rebell traps. More mature females were captured in Rebell traps baited with or without ammonium acetate than in McPhail-type traps baited with ammonium acetate. This study demonstrates that Rebell traps baited with an ammonium acetate dispenser can provide a more effective tool for monitoring and mass trapping of R. cerasi than the currently used unbaited Rebell traps.