Biological pest control in greenhouse crops is usually based on periodical releases of mass-produced natural enemies, and this method has been successfully applied for decades. However, in some cases there are shortcomings in pest control efficacy, which often can be attributed to the poor establishment of natural enemies. Their establishment and population numbers can be enhanced by providing additional resources, such as alternative food, prey, hosts, oviposition sites or shelters. Furthermore, natural enemy efficacy can be enhanced by using volatiles, adapting the greenhouse climate, avoiding pesticide side-effects and minimizing disrupting food web complexities. The special case of high value crops in a protected greenhouse environment offers tremendous opportunities to design and manage the system in ways that increase crop resilience to pest infestations. While we have outlined opportunities and tools to develop such systems, this review also identifies knowledge gaps, where additional research is needed to optimize these tools.

Novel lighting technology offers the possibility of improved arthropod integrated pest management (IPM) in artificially lighted crops. This review compiles the current knowledge on how greenhouse pest and beneficial arthropods are directly affected by light, with the focus on whiteflies. The effect of ultraviolet depletion on orientation and colour‐coded phototaxis are to some extent studied and utilised for control of the flying adult stage of some pest species, but far less is known about the visual ecology of commercially used biological control agents and pollinators, and about how light affects arthropod biology in different life stages. Four approaches for utilisation of artificial light in IPM of whiteflies are suggested: (a) use of attractive visual stimuli incorporated into traps for monitoring and direct control, (b) use of visual stimuli that disrupt the host‐detection process, (c) radiation with harmful or inhibitory wavelengths to kill or suppress pest populations and (d) use of time cues to manipulate daily rhythms and photoperiodic responses. Knowledge gaps are identified to design a road map for research on IPM in crops lighted with high‐pressure sodium lamps, light‐emitting diodes (LEDs) and photoselective films. LEDs are concluded to offer possibilities for behavioural manipulation of arthropods, but the extent of such possibilities depends in practice on which wavelength combinations are determined to be optimal for plant production. Furthermore, the direct effects of artificial lighting on IPM must be studied in the context of plant‐mediated effects of artificial light on arthropods, as both types of manipulations are possible, particularly with LEDs.

This review describes the effects of the current and emerging lighting technologies on plants, and the plant‐mediated effects on herbivorous and beneficial arthropods in high‐technology year‐round greenhouse production, where light quality, quantity and photoperiod differ from the natural environment. The spectrum provided by the current lighting technology, high‐pressure sodium lamp (HPSL), differs considerably from that of solar radiation. The major plant‐mediated effects on arthropods were predicted to result from (a) extended photoperiods and lower light integrals, (b) the attenuation of ultraviolet (UV) wavelengths, particularly UV‐B, (c) the high red: far‐red (R : FR) ratio and lower blue : red (B : R) in comparison with solar radiation and (d) the high proportion of yellow wavelengths during winter months. Of these light factors (a–d) (ceteris paribus), (a) and (b) were hypothesised to result in increased performance of herbivores in winter months, whereas the high R : FR ratio decreased herbivore performance or not affected it, at least when interlights are used. The predictions obtained on the basis of this review are also discussed in relation to the modifying factors prevailing in these production environments: enriched CO2 levels, high nutrient amounts, optimised irrigation and temperatures optimal for plants' needs. Based on the carbon/nitrogen and growth/differentiation balance theories, these modifying factors tend to produce plants that allocate most resources to growth at the expense of defensive secondary metabolism and physicochemical defensive structures. At the end, this review discusses knowledge gaps and future research prospects, in which light‐emitting diodes, the emerging lighting technology, play an important role by enabling the targeted manipulation of plant responses to different wavelengths.

We conclude that the new reduced risk insecticides metaflumizone and chlorantraniliprole and the fungicides myclobutanil, potassium bicarbonate and cyprodinil + fludioxonil are safe for greenhouse use in the presence of bumble bees. This information can be used preserve greenhouse pollination programs while maintaining acceptable pest management.

Insecticides are the most commonly used tactic to control western flower thrips (WFT), Frankliniella occidentalis Pergande (Thysanoptera: Thripidae), on greenhouse cucumber. However, WFT has developed resistance to several of the insecticides presently in use. In addition, some of these insecticides adversely affect greenhouse biological control agents used to control WFT, resulting in subsequent pest resurgence. Therefore, there is a need to identify novel insecticides with unique modes of action for use in integrated pest management (IPM) programs to effectively control WFT with minimal impact on associated biological control agents. In laboratory bioassays conducted in 2001, immature and adult WFT and three associated greenhouse biological control agents: Amblyseius cucumeris Oudemans (Acarina: Phytoseiidae), Orius insidiosus Say (Hemiptera: Anthocoridae) and Encarsia formosa Gahan (Hymenoptera: Aphelinidae) were exposed to direct, direct/residual, and residual contact applications of the novel biopesticide, spinosad (Conserve  120 SC), and the industry standard for whitefly control, endosulfan (Thiodan  50 WP). In all three types of assay, spinosad was effective against immature and adult WFT life stages. It showed low toxicity to A cucumeris, moderate toxicity to O insidiosus and high toxicity to E formosa. Greenhouse studies involving exposure of immature and adult WFT and adult biological control agents to cucumber leaves sprayed previously with spinosad supported the laboratory data. Spinosad showed low toxicity to A cucumeris exposed to leaves 1 day after treatment (DAT), moderate toxicity to O insidiosus 1 and 8 DAT, and high toxicity to E formosa up to 28 DAT. These data, along with spinosad's unique mode of action, suggest it would be a valuable reduced-risk control agent for greenhouse cucumber IPM programs.