Summary Sown flower strips are increasingly implemented within agri‐environment schemes (AES) to increase functional biodiversity and ecosystem services such as pollination or natural pest control, but their effectiveness in achieving these goals remains poorly studied. We tested the performance of experimentally sown annual flower strips specifically designed to promote natural enemies of aphids and their pest control services (tailored flower strips) in adjacent potato crops (n = 8) compared with control fields (n = 10). Flower strips consisted of 11 plant species providing abundant floral and extra‐floral resources. The abundance of key natural enemies of aphids (hoverflies, lacewings and ladybirds) and hoverfly species richness was greatly enhanced in tailored flower strips compared with potato control strips. This resulted in an average increase in the number of eggs deposited by hoverflies and lacewings by 127% and 48%, respectively, and a reduction in the number of aphids by 75% in adjacent potato crops. Synthesis and applications. We conclude that tailored flower strips can be an effective agri‐environmental measure to enhance natural enemies and aphid control in nearby crops. Indeed, tailored flower strips may help to reduce insecticide input in potato production as they significantly decrease the probability that action thresholds are reached. Promoting natural enemy abundance and diversity, as observed for hoverflies, may increase the stability of pest control and provide additional benefits to agro‐ecosystems in terms of natural enemy conservation. We thus recommend establishing tailored flower strips as a promising management option to reconcile the objectives of ecological intensification and biodiversity conservation.

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There was an error published in J. Exp. Biol. 213,[3388][3389][3390][3391][3392][3393][3394][3395][3396][3397] In the text of this paper, the proportions of two compounds in the plant-derived volatile mixture tested, i.e. (E)-2-hexenal and benzaldehyde, were inadvertently exchanged.In the second paragraph of the 'Chemicals and mixtures' section on p. 3389, it is stated that the mixture mimicking bioactive peach shoot volatiles was composed of (Z)-3-hexenyl acetate, (Z)-3-hexen-1-ol, (E)-2-hexenal, benzaldehyde and benzonitrile, at ratios of 69.74:14.62:13.24:2.25:0.15 vol./vol., respectively. The proportions of the compounds in the mixture should read: 69.74:14.62:2.25:13.24:0.15 vol./vol.The authors apologize for this error but confirm that the correct proportions of compounds were used throughout the study and therefore results and conclusions remain unaffected.

Insect herbivores that have more than one generation per year and reproduce on different host plants are confronted with substantial seasonal variation in the volatile blends emitted by their hosts. One way to deal with such variation is to respond to a specific set of compounds common to all host plants. The oriental fruit moth Cydia (=Grapholita) molesta is a highly damaging invasive pest. The stone fruit peach (Prunus persica) is its primary host, whereas pome fruits such as pear (Pyrus communis) are considered secondary hosts. In some parts of their geographic range, moth populations switch from stone to pome fruit orchards during the growing season. Here, we tested whether this temporal switch is facilitated by female responses to plant volatiles. We collected volatiles from peach and pear trees in situ and characterized their seasonal dynamics by gas chromatography-mass spectrometry. We also assessed the effects of the natural volatile blends released by the two plant species on female attraction by using Y-tube olfactometry. Finally, we related variations in volatile emissions to female olfactory responses. Our results indicate that the seasonal host switch from peach to pear is facilitated by the changing olfactory effect of the natural volatile blends being emitted. Peach volatiles were only attractive early and mid season, whereas pear volatiles were attractive from mid to late season. Blends from the various attractive stages shared a common set of five aldehydes, which are suggested to play an essential role in female attraction to host plants. Particular attention should be given to these aldehydes when designing candidate attractants for oriental fruit moth females.

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