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Background: The optimisation of the lure is essential for the implementation of trapping systems to control insect pests. In this work, the response of the red palm weevil (RPW), Rhynchophorus ferrugineus Olivier, to increasing emission rates of its aggregation pheromone (ferrugineol) and the efficacy of a convenient synthetic kairomone based on fermentation odours (ethyl acetate and ethanol) have been evaluated in different years and locations along the Mediterranean basin., Results: In general, although capture data and emission had noticeable variability among locations, significantly fewer RPW were captured in pyramidal Picusan® traps with the lowest ferrugineol emission rates tested (0.6-3.8 mg day -1 ). Captures increased rapidly with ferrugineol emission up to 4-5 mg day -1 ; then, higher emission rates did not improve or reduce captures, up to the highest emission rate tested of 50.9 mg day -1 . Thus, there is no evidence of an optimum release rate corresponding to a maximum of RPW catches. Traps baited with the synthetic kairomone (1:3 ethyl acetate/ethanol) captured 1.4-2.2 times more total weevils than traps baited only with ferrugineol. Moreover, in most of the locations, the synthetic blend was at least as effective as the local coattractants used (plant material + molasses)., Conclusions: Ferrugineol emission rate can vary in a wide range without significantly affecting RPW response. Coattractants based on fermenting compounds, ethyl acetate and ethanol, are able to improve the attractant level of ferrugineol and could be employed to replace non-standardised natural kairomones in RPW trapping systems after further optimisation of their proportions and doses. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

Background: Populations of red palm weevil (RPW), a severe pest of palms in Mediterranean countries, might be limited by semiochemical-based behaviour-disrupting methods. We evaluated the effects of electroantennogram (EAG)-active plant volatiles on the behaviour of RPWs from Italy and Israel. In field experiments, α-pinene, citronellol, geraniol, citral and 1-octen-3-ol were tested for their ability to disrupt attraction to pheromone-kairomone and molasses baited traps. Those that were found to be disruptive in the field were evaluated in a laboratory choice bioassay in individual cages for their effect on RPW female feeding and oviposition., Results: Field experiments showed reduced captures in traps loaded with geraniol (-57%), 1-octen-3-ol (-50%) or α-pinene (-45% to -60%); captures in citronellol- or citral-loaded traps did not differ from control. In laboratory experiments, 1-octen-3-ol was the most potent behaviour-modifying compound, eliciting a significant/marginally significant reduction in both feeding and oviposition at the lowest dose tested in both populations. Geraniol generally caused a strong reduction in feeding and oviposition at each dose tested (Israel), or at the highest dose (Italy). α-Pinene caused some reduction in feeding activity at the highest dose tested (Italy), but no consistent repellency (Israel)., Conclusion: Field and laboratory data suggest the potential for the use of 1-octen-3-ol, geraniol and α-pinene for RPW population management., (© 2014 Society of Chemical Industry.)

Background: The red palm weevil (RPW), Rhynchophorus ferrugineus Olivier, accidentally introduced into the European countries facing the Mediterranean basin, is becoming the most serious pest for ornamental palms in the urban environment. In the present work, tests were conducted on the electroantennogram (EAG) and behavioural responses of RPW adults to five selected synthetic palm esters, ethyl propionate, ethyl butyrate, ethyl isobutyrate, ethyl lactate and ethyl acetate, to assess the application of a mass trapping technique in an urban environment., Results: In the laboratory, EAG bioassays on RPW adults with the synthetic palm esters showed: (1) positive dose-dependent responses; (2) differences among the treatments; (3) a greater response to ethyl propionate; (4) a higher sensitivity of female antennae compared with male antennae. In the urban environment, RPW behavioural responses, evaluated over six biweekly observations on pheromone- and molasses- baited traps, showed that more adults were caught by traps supplemented with ethyl propionate and ethyl acetate than by traps supplemented with only ethyl propionate. Similar catches were recorded in the traps supplemented with ethyl propionate or ethyl acetate., Conclusion: This study supports the application of the mass trapping implemented with synthetic palm esters as a potential tool for the management of RPW populations to protect ornamental palms in urban environments., (Copyright © 2010 Society of Chemical Industry.)

The lethal doses of the pyrethroid deltamethrin were estimated for the egg parasitoid Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae), and the sub-lethal effects of an LD25 on female walking behaviour were evaluated. Linear speed of treated parasitoids was reduced compared with that of untreated ones for a period of up to 24 h. The sub-lethal effects of deltamethrin on parasitoid response to patches contaminated by a contact kairomone from its host, Nezara viridula L (Heteroptera: Pentatomidae), was also evaluated. Both treated and untreated parasitoids responded to host-contaminated patches by increasing residence time and decreasing linear speed. However, treated females showed a significantly lower residence time compared with untreated females. Both treated and untreated females showed a similar decrease over time in the proportion of time spent in the host-contaminated patch. Hence, we hypothesise that the sub-lethal effect of deltamethrin on host foraging may decrease T basalis efficacy in controlling N viridula.