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Floral plantings are promoted to foster ecological intensification of agriculture through provisioning of ecosystem services. However, a comprehensive assessment of the effectiveness of different floral plantings, their characteristics and consequences for crop yield is lacking. Here we quantified the impacts of flower strips and hedgerows on pest control (18 studies) and pollination services (17 studies) in adjacent crops in North America, Europe and New Zealand. Flower strips, but not hedgerows, enhanced pest control services in adjacent fields by 16% on average. However, effects on crop pollination and yield were more variable. Our synthesis identifies several important drivers of variability in effectiveness of plantings: pollination services declined exponentially with distance from plantings, and perennial and older flower strips with higher flowering plant diversity enhanced pollination more effectively. These findings provide promising pathways to optimise floral plantings to more effectively contribute to ecosystem service delivery and ecological intensification of agriculture in the future.

Background: The tomato russet mite, Aculops lycopersici, is a major worldwide pest infesting tomato crops for which only few control methods are available. At present, no commercialized beneficial organism has proven to be an effective biological control agent of the pest. As there is a strong need to develop alternatives to synthetic insecticides, we assessed the efficacy of an iolinid mite, Pronematus ubiquitus, as a preventive method against A. lycopersici in comparison with a curative treatment in a replicated experiment in the greenhouse. Results: After pre‐establishment of P. ubiquitus supplied with cattail pollen, followed by infestation of A. lycopersici, the predator was able to reduce pest populations by 98% as compared with control plants. Probably due to lack of food and high temperature, the number of P. ubiquitus decreased during the season and so the Eriophyid population rose, along with crop damage. The sulphur treatment could stop the progress of A. lycopersici, but their population levels remained high. Conclusion: Pronematus ubiquitus has great potential to prevent the establishment of the tomato russet mite. Even if a curative treatment affects the pest mite, the use of a preventive method is preferable as such insecticides/acaricides are harmful for beneficials and are applied after symptom appearance, when the pest pressure is already high. Despite the need to optimise management of the predator throughout the season, P. ubiquitus proved to be able to establish successfully on tomato plants. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Although most biological control programs use multiple biological agents to manage pest species, to date only a few programs have combined the use of agents from different guilds. Using sweet pepper (Capsicum annuum L.), the entomopathogenic fungus Akanthomyces muscarius ARSEF 5128, the tobacco peach aphid Myzus persicae var. nicotianae and the aphid parasitoid Aphidius ervi as the experimental model, we explored whether root inoculation with an entomopathogenic fungus is compatible with parasitoid wasps for enhanced biocontrol of aphids. RESULTS: In dual‐choice behavior experiments, A. ervi was significantly attracted to the odor of M. persicae‐infested C. annuum plants that had been inoculated with A. muscarius, compared to noninoculated infested plants. There was no significant difference in attraction to the odor of uninfested plants. Myzus persicae‐infested plants inoculated with A. muscarius emitted significantly higher amounts of indole, (E)‐nerolidol, (3E,7E)‐4,8,12‐trimethyltrideca‐1,3,7,11‐tetraene and one unidentified terpene compared to noninoculated infested plants. Coupled gas chromatography‐electroantennography, using the antennae of A. ervi, confirmed the physiological activity of these elevated compounds. Inoculation of plants with A. muscarius did not affect parasitism rate nor parasitoid longevity, but significantly increased the speed of mummy formation in parasitized aphids on fungus‐inoculated plants. CONCLUSION: Our data suggest that root inoculation of C. annuum with A. muscarius ARSEF 5128 alters the olfactory‐mediated behavior of parasitoids, but has little effect on parasitism efficiency or life‐history parameters. However, increased attraction of parasitoids towards M. persicae‐infested plants when inoculated by entomopathogenic fungi can accelerate host localization and hence improve biocontrol efficacy. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Manipulation of insect foraging may provide the basis for effective insect pest control strategies. Recent laboratory and small‐scale greenhouse experiments have shown that a blend of styrene and benzaldehyde is attractive to some Aphidius parasitoids, making it a good candidate for attracting and retaining these natural enemies in cropping systems. However, an appropriate dispenser type and appropriate dose for field application and its attraction range have yet to be identified. In this study, we performed experiments to determine an appropriate dispenser type – Omnilure® vs. low‐density polyethylene (LDPE) bags – and the most suitable dose to attract Aphidius colemani Viereck (Hymenoptera: Braconidae) under commercial greenhouse conditions and to determine the maximum distance of attraction. A mixture of 10 mg styrene and 100 μg benzaldehyde was the most attractive dose for A. colemani when provided by the dispensers under greenhouse conditions. The highest percentage of parasitoids was attracted when insects were released at a distance of 0.5 m from the Omnilure dispensers. Nevertheless, compared to the solvent control the blend of styrene and benzaldehyde remained attractive over a distance of up to 5 m. The potential application of these results in novel augmentation biocontrol strategies is discussed. [ABSTRACT FROM AUTHOR]

The current honey bee decline necessitates the use of alternative native pollinators to ensure global food security. Here, we compared the pollination behaviour and efficiency of the African honey bee (Apis mellifera) and six African endemic Meliponini (Meliponula bocandei, Dactylurina schmidti, Meliponula lendliana, Hypotrigona gribodoi, Meliponula ferruginea and Meliponula togoensis) in a greenhouse with the non-parthenocarpic cucumber variety Super Marketer. Honey bees and D. schmidti started foraging on introduction in the greenhouse, while M. lendliana and M. togoensis showed the longest delay. In most species, foragers collected nectar and pollen, excepting M. bocandei that specialized in nectar collection, and H. gribodoi and M. togoensis, specialized in pollen collection. African honey bees visited flowers the shortest, while H. gribodoi and D. schmidti had a 2-fold probing time, on average. Most stingless bees species had a lower hive activity with fewer foragers encountered per hour than for honey bees, except D. schmidti. M. bocandei, M. ferruginea, A. mellifera scutellata and H. gribodoi, yielded a seed germination percentage of around 90%. M. lendliana, M. togoensis and D. schmidti yielded a much lower seed germination percentage around 30%, which indicates that the quality of pollination was remarkably lower by using these three species. The highest sugar content was recorded in fruits from flowers pollinated by M. bocandei, African honey bees, D. schimdti or M. togoensis with the same solid content as the gold standard method, i.e., hand cross-pollination. We found that M. bocandei was the most efficient cucumber pollinator of all species tested: because pollination by this species yielded the largest and heaviest fruits and the highest seed numbers. [ABSTRACT FROM AUTHOR]

Insect communities consist of species from several trophic levels that have to forage for suitable resources among and within larger patches of nonresources. To locate their resources, insects use diverse stimuli, including olfactory, visual, acoustic, tactile and gustatory cues. While most research has focused on cues derived from plants and other insects, there is mounting evidence that insects also respond to volatile organic compounds (VOCs) emitted by microorganisms. However, to date little is known about how the olfactory response of insects within and across different trophic levels is affected by bacterial VOCs. In this study, we used Y‐tube bioassays and chemical analysis of VOCs to assess how VOCs emitted by bacteria affect the olfactory response of insects of the same and different trophic levels. Experiments were performed using two aphid species (Amphorophora idaei Börner and Myzus persicae var. nicotianae Blackman), three primary parasitoid species (Aphidius colemani Viereck, A. ervi Haliday, and A. matricariae Viereck), and two hyperparasitoid species (Asaphes suspensus Nees and Dendrocerus aphidum Rondani). Olfactory responses were evaluated for three bacterial strains (Bacillus pumilus ST18.16/133, Curtobacterium sp. ST18.16/085, and Staphylococcus saprophyticus ST18.16/160) that were isolated from the habitat of the insects. Results revealed that insects from all trophic levels responded to bacterial volatiles, but olfactory responses varied between and within trophic levels. All bacteria produced the same set of volatile compounds, but often in different relative concentrations. For 11 of these volatiles we found contrasting correlations between their concentration and the behavior of the primary parasitoids and hyperparasitoids. Furthermore, olfactometer experiments on three of these compounds confirmed the contrasting olfactory responses of primary parasitoids and hyperparasitoids. The potential of these findings for the development of novel semiochemical‐based strategies to improve biological aphid control has been discussed. [ABSTRACT FROM AUTHOR]

Chrysoperla species include well-known predators of aphids and other soft-bodied arthropods. As such, they are considered important biological control agents of herbivorous pests in agroecosystems where many of green lacewings species occur. Despite the high number of species of the genus Chrysoperla , only a few have been assessed for the predation efficiency of their larvae against pests infesting plants, and even fewer are currently marketed for use in biocontrol practice. Difficulties in species identification within the Chrysoperla carnea complex species in particular has been related to varying success of commercial C. carnea s.l. releases in the field. In this study, we assessed the ability of two Chrysoperla species, Chrysoperla agilis a member of the carnea cryptic species group, and Chrysoperla mutata of the pudica group to consume aphid and mealybug individuals and suppress their populations in sweet pepper plants. We found that third-instar larvae of both species were able to consume a high number of aphids (approximately 120 nymphs per larva) and mealybugs (approximately 105 nymphs per larva) within 24 h. Furthermore, the release of second-instar larvae of both C. agilis and C. mutata was shown to be remarkably efficient in suppressing the pest populations in long-term greenhouse experiments. Aphid populations were suppressed by approximately 98% and mealybugs by 78% as compared to control plants. Our results highlight the predation efficiency and the biocontrol potential of two widespread Chrysoperla species for their use in pest control. [ABSTRACT FROM AUTHOR]