Upon herbivory, plants release herbivore-induced plant volatiles (HIPVs), which induce chemical defenses in the plant as well as recruit natural enemies. However, whether synthetic HIPVs can be employed to enhance biological control in a cultivated crop in the field is yet to be explored. Here we show that a biodegradable formulation loaded with induced and food-signaling volatiles can selectively recruit the common green lacewing, Chrysoperla carnea, and reduce pest population under field conditions. In apple orchards, the new formulation attracted lacewing adults over a 4-week period, which correlated well with independent assessments of the longevity of the slow-release matrix measured through chemical analyses. In barley, lacewing eggs and larvae were significantly more abundant in treated plots, whereas a significant reduction of two aphid species was measured (98.9% and 93.6% of population reduction, for Sitobion avenae and Rhopalosiphum padi, respectively). Results show the potential for semiochemical-based targeted recruitment of lacewings to enhance biological control of aphids in a field setting. Further research should enhance selective recruitment by rewarding attracted natural enemies and by optimizing the application technique.

Several important vegetable crops grown outdoors in temperate climates in Europe can be damaged by the root-feeding larvae of Diptera (Delia radicum, Delia floralis, Chamaepsila rosae, Delia platura, Delia florilega, Delia antiqua). Knowledge of pest insect phenology is a key component of any Integrated Pest Management (IPM) strategy, and this review considers the methods used to monitor and forecast the occurrence of root-feeding flies as a basis for decision-making by growers and the ways that such information can be applied. It has highlighted some current management approaches where such information is very useful for decision support, for example, the management of C. rosae with insecticidal sprays and the management of all of these pests using crop covers. There are other approaches, particularly those that need to be applied at sowing or transplanting, where knowledge of pest phenology and abundance is less necessary. Going forward, it is likely that the number of insecticidal control options available to European vegetable growers will diminish and they will need to move from a strategy which often involves using a single ‘silver bullet’ to a combination of approaches/tools with partial effects (applied within an IPM framework). For the less-effective, combined methods, accurate information about pest phenology and abundance and reliable decision support are likely to be extremely important.

Olfaction is the most important sensory mechanism by which many insects interact with their environment and a wind tunnel is an excellent tool to study insect chemical ecology. Insects can locate point sources in a three-dimensional environment through the sensory interaction and sophisticated behavior. The quantification of this behavior is a key element in the development of new tools for pest control and decision support. A wind tunnel with a suitable flight section with laminar air flow, visual cues for in-flight feedback and a variety of options for the application of odors can be used to measure complex behaviour which subsequently may allow the identification of attractive or repellent odors, insect flight characteristics, visual-odor interactions and interactions between attractants and odors lingering as background odors in the environment. A wind tunnel holds the advantage of studying the odor mediated behavioural repertoire of an insect in a laboratory setting. Behavioural measures in a controlled setting provide the link between the insect physiology and field application. A wind tunnel must be a flexible tool and should easily support the changes to setup and hardware to fit different research questions. The major disadvantage to the wind tunnel setup described here, is the clean odor background which necessitates special attention when developing a synthetic volatile blend for field application.

Conservation biological control (CBC) is a sustainable measure for ecological intensification in agriculture to establish and maintain robust natural enemy populations. CBC is contributing to integrated pest management with reduced use of pesticides and support of native biodiversity in agroecosystems. Despite rapidly expanding research on CBC during the last decades, its application in pest management at the farm level is very limited. Here, we tested a CBC strategy in a 5-year on-farm study at three locations in East Norway. This CBC strategy combined two tools to increase biological control of aphids in spring barley; 1-ATTRACT, the application of a volatile organic compound (VOC) attractant that increases lacewing egg laying, and 2-HABITAT, the maintenance of natural border vegetation. We found that the VOC attractants recruited natural enemies and guided them to the right place at the right time from the border vegetation into the cropping area to control the aphid population efficiently and reliably. The results also showed that the VOC attractants combined with periodical maintained natural border vegetation provided a higher lacewing activity and aphid suppression than with annual sown floral buffer strips. We found that maintained natural border vegetation supported by VOC attractants provided lacewing populations that controlled aphids up to 100 m into the cropping area. Without VOC attractants we recorded lacewing activity up to 50 m from the border into the cropping area if natural border vegetation was available, and up to 25 m if no border vegetation existed. The overall results demonstrated the feasibility of this CBC approach under Norwegian farming conditions leading to the successful adoption of this CBC-strategy by the farming community.