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Field margins have an important ecological role in agroecosystems including hosting beneficial insect such as syrphids. However, little is known of syrphid preferences for different types of field margins. Syrphids were sampled in field margins in an organic agroecosystem to test the hypothesis that syrphid abundance in field margins depends not only on the floral resource abundance but also on field margin component type, field margin complexity, and adjacent land-use type. Floral resource abundance had the greatest influence on the number of syrphids surveyed. Field margin characteristics were deemed to effect syrphid abundance both independently of their effect on floral resources and by altering floral resource abundance. Syrphids were more abundant in field margins adjacent to cropped fields than those adjacent to grazed fields or roads. More syrphids were found in ditch components than in tree or grass strip components. The influence of floral resources on syrphid abundance varied depending on their botanical families, although no significant differences were observed for the effect of botanical family floral resource index on syrphid abundance. These findings demonstrate that field margin characteristics play an important role in facilitating plant–syrphid interactions and offer an insight in agroecosystem management for the promotion of beneficial insects. The influence of field margin characteristics on other beneficial insect groups should also be investigated.

Spiders are key predators in many agroecosystems, including orchards. Despite the importance of spiders in biological control, pesticide nontarget effects on this group are poorly described. This is especially true for herbicides, which spiders frequently encounter as they move between the ground cover and tree canopy. We sought to determine the nontarget effects of seven herbicides used in orchards on three species of spiders that are commonly found in Washington state (USA) orchards: Pelegrina aeneola (Curtis) (Araneae: Salticidae), Philodromus cespitum (Walckenaer) (Araneae: Philodromidae), and Phanias watonus (Chamberlin & Ivie) (Araneae: Salticidae). Immature spiders were collected from orchards and used in laboratory assays. Single spiders were placed in vials with dried herbicide residues and mortality was evaluated after 1, 2, and 5 d. We also evaluated herbicide impacts on prey consumption rates and on spider movement using motion-tracking software. Only oxyfluorfen caused significant spider mortality. P. cespitum seemed to be less acutely sensitive to oxyfluorfen than the two salticid species. Several herbicide treatments significantly increased locomotion in P. cespitum, whereas rimsulfuron numerically decreased movement of P. aeneola. Sulfonylurea herbicides (rimsulfuron, halosulfuron) decreased prey consumption of P. aeneola. Our work indicates that although spiders may be less acutely sensitive to some pesticides than beneficial insects, they can be affected by sublethal effects of herbicides. Future work should determine if herbicide applications impact spider abundance in the field and reduce biological control services. In general, more work is needed on the impacts of herbicides on natural enemies.

Designing wildflower habitats to support beneficial insects providing pollination and pest control services is important for supporting sustainable crop production. It is often desirable to support both groups of insects, making the selection of resource plants for insect conservation programs more challenging. Moreover, the process of selecting resource plants is complicated by the array of possible options in each region, and the need to provide resources over the entire growing season. Identifying traits shared by resource plants that are attractive to both bees and natural enemies can reduce the need to evaluate new plants in each region, by providing a guide for the types of plants expected to be rewarding to these insects. Using insect visitation data collected from replicated common garden plantings of native wildflower and shrub species from the Great Lakes region of the United States, we found a high degree of correlation between the abundance of bees and natural enemies visiting native plant species. These results were used to identify a set of 15 plant species that can provide resources for these insects throughout the summer. Across all tested species, pollen quantity per flower and the week of bloom were positively correlated with some, but not all, taxonomic groupings of beneficial insects. In contrast, floral area was consistently positively associated with visitation of both natural enemies and wild bees. This trait is easy to document and can allow for efficient local testing of potential resource plants, providing a faster path to implementing insect conservation in working landscapes.

Background In recent years, Microtermes obesi (Holmgren) (Blattodea: Termitidae) has been recorded as a major pest of tea crop, causes significant losses in production. Managing termite pests in tea crops through an integrated approach has been suggested, and the use of microbial biocontrol agent is one of the economical methods. The present study evaluated the pathogenic efficacy of an entomopathogenic fungus Metarhizium anisopliae s.l. (= M. anisopliae) against M. obesi damaging tea plants under field conditions. Results Metarhizium anisopliae s.l. was formulated as 5% aqueous suspension (AS). Large-scale field trials with formulated entomopathogen revealed that 1000 and 1200 ml concentrations of M. anisopliae s.l. 5%AS (each concentration containing 2 × 107 conidia/ml) each in 400 l of water/ha significantly (P M. obesi in tea gardens at Dooars and Darjeeling regions, India. In the field study, M. anisopliae s.l. was more effective than the standard insecticide and was non-pathogenic on the beneficial insects present in the tea gardens. In addition, M. anisopliae s.l. 5%AS had no phytotoxic effect on the tea leaves, with acceptable organoleptic attributes. Conclusion Metarhizium anisopliae s.l. isolate can be commercialized as an alternative natural termiticide to reduce the load of synthetic insecticides in the tea crop.

The use of insecticides in flowering oilseed rape (Brassica napus L.) against pest insects such as the brassica pod midge (Dasineura brassicae W.) often conflicts with the protection of pollinating and beneficial insects. Dasineura brassicae is a major pest insect in European oilseed rape production. However, a comprehensive and sustainable pest control strategy within the framework of integrated pest management (IPM) does not exist, and little research on the insect has been published during the past two decades. This paper reviews the existing knowledge about D. brassicae along its life cycle and is intended to form the basis for further research activities on pod-damaging pest insects in oilseed rape. Important knowledge gaps are identified, regarding the significance of natural enemies, diapause induction, and predictions on damage potential, based on initial pest insect population. The short lifespan of the adults is particularly challenging in praxis. The implementation of IPM for D. brassicae is discussed on the basis of the four IPM steps (set an economic threshold, establish pest monitoring, preventive measures, and direct control measures) and remaining hurdles, as well as potential solutions for a better IPM, are identified. For D. brassicae, there is no science-based economic threshold and no applicable monitoring methods for farmers, which hinders a field-specific damage forecast and the precise timing of insecticide applications. Research into improved monitoring (e.g. selective attractants, real-time monitoring using remote-sensing technologies) appears to be a promising step towards an integrated pest management of D. brassicae.

Introducing areas of wildflower vegetation within crop fields has been shown to enhance pollinator activity and pollination services to crops, and findings in Europe showed an interaction effect between floral treatments and landscape context. Natural fynbos patches in the South African Cape Floristic Region (CFR) are potential reservoirs for beneficial insects that could enhance pollinator populations and crop pollination in commercial apple orchards. However, the effect of proximity to natural habitat and floral enhancement treatments on crop pollinators and yield are yet to be fully tested in southern temperate regions.\ud \ud To elucidate the impact of enhanced floral resources to apple flower visitors and crop yield, we established small experimental patches of flowers in non-productive areas of commercial apple Malus domestica orchards in the CFR. Experimental orchards were embedded in landscapes with varying proportions of natural habitat within 1 km. We used pollinator exclusion experiments to determine the benefits of insect pollination on apple yield, quality and economic value.\ud \ud We found that the primary pollinator of apple flowers in the region is the endemic Cape honey bee, Apis mellifera capensis. Floral plantings enhanced overall pollinator abundance and honey bee flower visitation within the orchards, and positively affected apple size and economic value. Increased landscape complexity had a significantly positive effect on wild bees but not on honey bees.\ud \ud Synthesis and applications. We demonstrate that presence of floral plantings within orchards enhances pollinator activity within apple orchards and apple quality. This sustainable management practice may represent a profitable choice for growers, which could increase pollination services while reducing reliance on renting hives. These practices can indirectly contribute to increased landscape-scale resilience and connectivity while also benefiting pollinators within the remaining natural habitat.

Agroecosystems produce profound alterations on the structure and functioning of the original environment, mainly due to the reduction of biodiversity. Flower flies (Diptera: Syrphidae) are potentially useful organisms for the diverse ecosystem services they provide. We studied syrphids collected in a Pampean agroecosystem to assess richness, abundance, host plants, and the ecosystem services they could offer. Flower flies were represented by three subfamilies, eight tribes, 17 genera, and 26 species/morphospecies. Adults of these flies visited flowers of 44 species of wild and/or cultivated plants and exhibited a generalist interaction pattern. Larvae of the most abundant species were predators (mainly soft-bodied Hemiptera) and/or decomposers/aquatic filters. Only one species was pollinivorous. Our results, together with the scarce published bibliography, suggest that the syrphid communities of the highly modified Pampean region are composed of a few very abundant species and many rare or low representative species.

In June of 2013 an application of dinotefuran on an ornamental planting of European linden trees (Tilia cordata Mill. [Malvales: Malvalceae]) in a shopping mall parking lot in Wilsonville, Oregon provoked the largest documented pesticide kill of bumble bees in North America. Based on geographic information systems and population genetic analysis, we estimate that between 45,830 and 107,470 bumble bees originating from between 289 and 596 colonies were killed during this event. Dinotefuran is a neonicotinoid that is highly effective in exterminating and/or harming target pest insects and non-target beneficial insects. Analysis to detect the concentration of pesticides in flowers that received foliar application revealed that the minimum reported dinotefuran concentration of a sampled T. cordata flower was 7.4 ppm, or in excess of 737% above the LC50 of the beneficial pollinator, the honey bee (Apis mellifera Linnaeus, 1758 [Hymenoptera: Apidae]). Furthermore, sampled Vosnesensky bumble bees (Bombus vosnesenskii Radoskowski, 1862 [Hymenoptera: Apidae]) were found to have an average dinotefuran concentration of 0.92 ppm at the time of death, which exceeds the maximum LC50 of A. mellifera (0.884 ppm). Our study underscores the lethal impact of the neonicotinoid pesticide dinotefuran on pollinating insect populations in a suburban environment. To our knowledge, the documentation and impact of pesticide kills on wild populations of beneficial insects has not been widely reported in the scientific literature. It is likely that the vast majority of mass pesticide kills of beneficial insects across other environments go unnoticed and unreported.

The knowledge of the entomological fauna in productive systems is important for the agroecological management since beneficial insects are a key resource for pest management in horticultural systems. Scientific information on the biodiversity present in a given area is essential as well as the ecological function and/or feeding habits of the insects. In Alto Valle de Río Negro and Neuquén, horticultural production systems can be described as highly dependent on chemical inputs for pest management and fertilization. The aim of this study is to carry out an inventory of the biodiversity of some families of Hemiptera, Coleoptera (Curculionidae) and Hymenoptera present in peri-urban and rural farms located in Neuquén and Río Negro, respectively. Insects were collected through pitfall and sweeping net on tomato and pepper crops and the surrounding non-cultivated areas. Idiosystatus Berg (Auchenorrhyncha) was cited for the first time from Argentina. Species cited for the first time from Neuquén: Hemiptera: Auchenorrhyncha: Acanalonia chloris (Berg), Syncharina punctatissima (Signoret), Amplicephalus dubius Linnavuori, Exitianus obscurinervis (Stål), Agalliana ensigera Oman and Bergallia signata (Stål); Hemiptera: Heteroptera: Harmostes (Harmostes) prolixus Stål and Atrachelus (Atrachelus) cinereus (Fabricius); Coleoptera: Curculionidae: Hypurus bertrandi (Perris), Naupactus leucoloma Boheman, Otiorhynchus rugosostriatus (Goeze) and Sitona discoideus Gyllenhal and Hymenoptera: Xylocopa (Neoxylocopa) augusti Lepeletier and Pseudagapostemon (Neagapostemon) singularis Jörgensen. Species cited for the first time from Río Negro: Hemiptera: Auchenorrhyncha: Amplicephalus dubius Linnavuori, Amplicephalus marginellanus Linnavuori, Circulifer tenellus (Baker) and Xerophloea viridis (Fabricius); Hemiptera: Heteroptera: Tupiocoris cucurbitaceus (Spinola), Atrachelus (Atrachelus) cinereus (Fabricius), Dichelops furcatus (Fabricius) and Harmostes (Harmostes) prolixus Stål; Coleptera: Curculionidae: Naupactus xanthographus (Germar) and Hymenoptera: Diadasia pereyrae (Holmberg) and Dialictus autranellus (Vachal). El conocimiento de la fauna entomológica presente en los sistemas productivos es importante para el manejo agroecológico ya que los insectos beneficiosos son un recurso clave para el manejo de plagas en los sistemas hortícolas. Es esencial contar con información científica sobre la biodiversidad presente en un área determinada y la función ecológica y/o los hábitos alimenticios de los insectos. En el Alto Valle de Río Negro y Neuquén, los sistemas de producción hortícola pueden describirse como altamente dependientes de los insumos químicos para el manejo de plagas y fertilización. El objetivo de este estudio es realizar un inventario de la biodiversidad de algunas familias de Hemiptera, Coleoptera (Curculionidae) e Hymenoptera presentes en las chacras periurbanas y rurales ubicadas en Neuquén y Río Negro, respectivamente. Los insectos fueron recolectados a través de trampas de caída y red entomológica en cultivos de tomate y pimiento, y áreas circundantes no cultivadas. Idiosystatus Berg (Auchenorrhyncha) fue citado por primera vez en Argentina. Especies citadas por primera vez en Neuquén: Hemiptera: Auchenorrhyncha: Acanalonia chloris (Berg), Syncharina punctatissima (Signoret), Amplicephalus dubius Linnavuori, Exitianus obscurinervis (Stål), Agalliana ensigera Oman y Bergallia signata (Stål); Hemiptera: Heteroptera: Harmostes (Harmostes) prolixus Stål y Atrachelus (Atrachelus) cinereus (Fabricius); Coleoptera: (Curculionidae): Hypurus bertrandi (Perris), Naupactus leucoloma Boheman, Otiorhynchus rugosostriatus (Goeze) y Sitona discoideus Gyllenhal e Hymenoptera: Xylocopa (Neoxylocopa) augusti Lepeletier and Pseudagapostemon (Neagapostemon) singularis Jörgensen. Especies citadas por primera vez en Río Negro: Hemiptera: Auchenorrhyncha: Amplicephalus dubius Linnavuori, Amplicephalus marginellanus Linnavuori, Circulifer tenellus (Baker) y Xerophloea viridis (Fabricius); Hemiptera: Heteroptera: Tupiocoris cucurbitaceus (Spinola), Atrachelus (Atrachelus) cinereus (Fabricius), Dichelops furcatus (Fabricius) y Harmostes (Harmostes) prolixus Stål; Coleoptera: Curculionidae: Naupactus xanthographus (Germar) e Hymenoptera: Diadasia pereyrae (Holmberg) y Dialictus autranellus (Vachal). Área Investigación y Desarrollo Tecn. Agricultura Familiar - Región Patagonia Fil: Alvarez, Leopoldo Jesus. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: Bernardis, Adela M. Universidad Nacional del Comahue. Facultad de Ciencias del Ambiente y la Salud; Argentina Fil: Defea, Bárbara Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina Fil: Dellapé, Pablo Matías. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil. Del Río, Maria Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina Fil: Gittins Lopez, Cecilia Gabriela. Instituto Nacional Tecnología Agropecuaria (INTA). Área Investigación y Desarrollo Tecn. Agricultura Familiar - Región Patagonia; Argentina Fil: Lanteri, Analía A. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: López Armengol, María Fernanda. Universidad Nacional del Comahue. Facultad de Ciencias del Ambiente y la Salud; Argentina. Instituto Nacional Tecnología Agropecuaria (INTA). Área Investigación y Desarrollo Tecn. Agricultura Familiar - Región Patagonia; Argentina Fil: Marino de Remes Lenicov, Ana María. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: Minghetti, Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: Paradell, Susana Liria. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CIC PBA); Argentina Fil: Rizzo, Maria Estefania. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Dispersal is a key ecological process affecting community dynamics and the maintenance of populations. There is increasing awareness of the need to understand individual dispersal potential to better inform population-level dispersal, allowing more accurate models of the spread of invasive and beneficial insects, aiding crop and pest management strategies. Here, fine-scale movements ofPoecilus cupreus, an important agricultural carabid predator, were recorded using a locomotion compensator and key movement characteristics were quantified. Net displacement increased more rapidly than predicted by a simple correlated random walk model with near ballistic behaviour observed. Individuals displayed a latent ability to head on a constant bearing for protracted time periods, despite no clear evidence of a population level global orientation bias. Intermittent bouts of movement and non-movement were observed, with both the frequency and duration of bouts of movement varying at the inter- and intra-individual level. Variation in movement behaviour was observed at both the inter- and intra- individual level. Analysis suggests that individuals have the potential to rapidly disperse over a wider area than predicted by simple movement models parametrised at the population level. This highlights the importance of considering the role of individual variation when analysing movement and attempting to predict dispersal distances.

Biological stimulation induced by low doses of toxicants or other stressors is known as hormesis. Hormetic stimulation of life history traits in insect pests can negatively impact agriculture, but stimulation of beneficial insects could be leveraged to enhance biological control agents. We examined whether low doses of imidacloprid could enhance oviposition, fecundity, fertility, and survival in the beneficial stink bug predator, Podisus maculiventris (Say) (Hemiptera: Pentatomidae), exposed at different life stages and across two generations. When treated as young adults, P. maculiventris fecundity was stimulated at 0.5 and 1.0 mg/liter imidacloprid (

In citrus groves, beneficial insects that reduce abundance of pests are considered a key component of integrated pest management strategies. The aim of this article was to assess the biodiversity of parasitoids and predators in citrus orchards in Moroccoto facilitate future investigations on their potential as biocontrol agents. Data of 105 citrus beneficial insects were gathered and summarized in a data matrix. Variables such nature, target pests, type, establishment, and efficacy were assessed. More than two-thirds of parasitoids and predators species identified in citrus groves of Morocco (105 species) are native (> 70%). Both groups represent only a small fraction of the introduced species. The mostly attack armored scale insects (Diaspididae) and aphids (Aphididae). The ladybeetle Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae) is the first beneficial species introduced in 1921 to the Moroccan citrus orchards to control the cottony cushion scale Icerya purchasi (Maskell) (Hemiptera: Monophlebidae). Major introductions of these parasitoids and predators were carried out during the ninetieth to control the main citrus pests whereas they were accidentally introduced. These purposely introduced species are mainly Aphelinidae, Encyrtidae, Eulophidae, Coccinellidae, and Phytoseiidae. Whereas a high proportion of the introduced beneficial insects was established and no species have been reported to be harmful to this date. Considering only the introduced species used in classical biological control context, about 20 and 40% of them are considered as effective or partially effective, respectively.

Insects provide key ecosystem services such as pollination, dung burial, soil enhancement, and pest control. Global insect decline requires restoration of the plant–insect mutualistic interactions. By using magnet plants, it is possible to supply beneficial insects with better resource availability and create more sustainable habitats. Current management practices recommend using Umbellifers (Apiales, Apiaceae) in restoration projects. However, analyses of the structure and dynamics of entomofauna associated with this plant family is needed to facilitate practical actions. Here the attention is focused on species composition and seasonal dynamics of beneficial insects associated with sweet fennel Foeniculum vulgare (Apiaceae, Umbelliferae) in Crimea. A 2-year sampling campaign identified 60 insect species from 40 genera across 20 families and four orders: Hymenoptera, Diptera, Coleoptera, and Neuroptera. These insects represented the groups such as social wasps, bees, ants, bumble bees, potter wasps, beetles, lacewings, mud daubers, tachinid flies, and hoverflies. Social wasps and hoverflies dominated in sample collections. Most of insects collected benefit ecosystems and provide essential ecosystem services. During fennel’s flowering season, the number of visits by bumble bees, beetles, bees. and wasps decreased. Contrastingly, dipterans visitation increased towards the end of the season. Such trends might be explained with fennel’s functional protandry, bias in nectar production between male and female flower stages, and insects’ feeding preferences. F. vulgare attracts a diverse assemblage of beneficial insects and consequently can be recommended as a magnet species. When aiming to attract specific insect groups, the seasonal dynamics of fennel’s associated entomofauna should be considered.

1. Hover flies (Syrphidae: Diptera) are a cosmopolitan group of insects that provide important ecosystem services including pollination and pest control. The seasonal migration of hover flies is probably best known in Europe, but it remains unstudied in many other parts of the world. 2. Australia is believed to be home to around 160 hover fly species, some of which are common in urban and agricultural environments. The current evidence for hover fly migration in Australia is scarce and anecdotal, yet migration may be critical to the success of pollination and the biological control of aphids. 3. In this study, species occurrence records from an online biodiversity database (Atlas of Living Australia) were used to look for evidence of migratory behaviours in all Australian hover flies with more than 200 occurrence records. 4. Four of the 10 species displayed seasonal changes in their distribution consistent with migration, including Australia's two most abundant species: Melangyna viridiceps and Simosyrphus grandicornis. This work is an important first step in understanding the prevalence of migration in Australian hover flies. However, confirmation of our findings requires additional evidence to rule out other plausible explanations for the observed patterns. 5. Based on changes in summer and winter latitudinal distribution, it is estimated that some Australian hover flies may make annual migrations of 400–1800 km. 6. This work suggests that the management of beneficial insects requires consideration of factors at both local and continental scales, as landscape use changes may have an impact on ecosystem services delivered hundreds of kilometres away.

Context Predatory insects contribute to the natural control of agricultural pests, but also use plant pollen or nectar as supplementary food resources. Resource maps have been proposed as an alternative to land cover maps for prediction of beneficial insects. Objectives We aimed at predicting the abundance of crop pest predating insects and the pest control service they provide with both, detailed flower resource maps and land cover maps. Methods We selected 19 landscapes of 500 m radius and mapped them with both approaches. In the centres of the landscapes, aphid predators – hoverflies (Diptera: Syrphidae), ladybeetles (Coleoptera: Coccinellidae) and lacewings (Neuroptera: Chrysopidae) – were surveyed in experimentally established faba bean phytometers (Vicia faba L. Var. Sutton Dwarf) and their control of introduced black bean aphids (Aphis fabae Scop.) was recorded. Results Landscapes with higher proportions of forest edge as derived from land cover maps supported higher abundance of aphid predators, and high densities of aphid predators reduced aphid infestation on faba bean. Floral resource maps did not significantly predict predator abundance or aphid control services. Conclusions Land cover maps allowed to relate landscape composition with predator abundance, showing positive effects of forest edges. Floral resource maps may have failed to better predict predators because other resources such as overwintering sites or alternative prey potentially play a more important role than floral resources. More research is needed to further improve our understanding of resource requirements beyond floral resource estimations and our understanding of their role for aphid predators at the landscape scale.

Beneficial plant–microbe interactions in the rhizosphere have been found to enhance plant growth and development. Arbuscular mycorrhizal fungi (AMF), a major group among these microbes, have been found to improve plant fitness through mycorrhizal symbiosis. Despite being well documented in various natural and domesticated study systems, few studies have examined whether AMF also has cascading effects on other traits, such as influencing insect community dynamics through attraction/repulsion of beneficial and harmful insects. To test this, we planted Sorghum-sudangrass (Sorghum x drummondii), a fast-growing annual grain/forage crop, either inoculated with commercial AMF mix or left as control in lab and field experiments. We hypothesized that AMF would enhance plant growth and influence the recruitment of insect herbivores and their natural enemies due to possible alterations in plant defense pathways. Our results suggest that while AMF-inoculated plants had significantly better germination, growth, and establishment; they also experienced a lower initial incidence of Spodoptera frugiperda, a major herbivore on Sorghum in the Lower Rio Grande Valley. In addition, our insect community trapping experiment revealed that AMF-inoculated plants attracted significantly more beneficial insects (predators and parasitoids) and a lower number of damaging herbivores. Taken together, our field and lab data show that AMF can not only positively influence plant growth traits but can also provide defenses against herbivores by selectively attracting beneficial insects and repelling herbivores, with implications for sustainable pest management strategies.

A study was conducted to investigate the diurnal activity patterns of hymenopteran pollinators in culinary melon and the dynamics of hymenopteran pollinators of five selected cucurbitaceous vegetables viz.,culinary melon, bitter gourd, pumpkin and ridge gourd in 34 locations of Kerala from 06:00 h to 18:00 h with a cone type hand net. The study revealed that Apis cerana indica was dominant in culinary melon, pumpkin and ridgegourd and Tetragonula travancorica was dominant in bitter gourd and ash gourd, A. cerana indica, T. travancorica and Halictus sp. recorded highest foraging speed during 10:00 h to 11:00 h; Ceratina hieroglyphica and Lasioglossum sp. recorded highest foraging speed during 09:00-10:00 h; T. travancorica, C. hieroglyphica and Lasioglossum sp. recorded maximum foraging rate during 10:00 h to 11:00 h; A. cerana indica and Halictus sp. recorded highest foraging rate during 11:00-12:00 h and 09:00-10:00 h.

The efficacy of commercially available chemical insecticides and biopesticides on the cotton mealybug (CMB), Phenacoccus solenopsis, was evaluated in the glasshouse. Spirotetramat, sulfoxaflor and buprofezin were identified as key insecticides for use in integrated pest management (IPM) strategies aimed at controlling CMB without flaring other co-occurring pests. When used as a single application, spirotetramat and sulfoxaflor at the rate of 96 g (active ingredient, ha−1) provided variable control of CMB. Spirotetramat used in a double spray tactic (two sequential sprays, 14–15 days apart) without crop oil provided ≥80% control of adult CMB while the addition of oil (5% v/v) increased control to ≥90%. Clothianidin synergised the spirotetramat + oil combination and was identified as a potentially useful tank mix option for use in situations where a quick knockdown of high density and/or large infestation of CMB is required, or to treat high risk infestations in squaring or younger cotton when the abundance of beneficial insects is typically low. Sulfoxaflor used in a double spray tactic provided ≥90% control of adult CMB. The addition of Pulse® penetrant (0.5% v/v) to both options improved overall efficacy. Addition of crop oil to sulfoxaflor did not yield any tangible benefits. Spirotetramat and buprofezin were identified as important tools in managing situations where whitefly (Bemisia tabaci) is the primary pest management target, but CMB is also present in the crop. Buprofezin was effective on early instar mealybugs; this makes it an option for arresting CMB population growth while allowing the beneficial insect populations to increase. Sulfoxaflor was shown to be a useful option in situations where CMB is present along with key pests such as mirids (Creontiades spp.). Mealybugs are typically well controlled by naturally occurring beneficial insects without the need for insecticide use. Chemical insecticides for CMB control should be considered only as a last resort and deployed within the bounds of an IPM strategy.

Wasps contribute to environmental quality and ecosystem services, and play a key role in the functioning of many environments. The present study identified the diversity of species of solitary wasps that occupied trap-nests in farming environments. as well as the architecture of the nests found. The study focused on three areas of agroecosystem, where 30 blocks of trap-nests, with four diameters (5 mm, 7 mm, 9 mm, and 11 mm), were installed. A total of 56 nests were occupied by solitary wasps, with the most frequent species being Trypoxylon sp.1 (N=100, 54.9%), Pachodynerus cf. brevithorax (N=31, 17.0%), Trypoxylon sp.2 (N=27, 14.8%) and Caenochrysis nigropolita (N=9, 4.9%). The wasps occupied preferentially the trap-nests of 5 mm and 7 mm in diameter. Six wasp families were recorded, with the most abundant being the Crabronidae with 127 individuals, followed by the family Vespidae (N=36). Reduced number of species was recorded in the study area with frequent use of pesticides, and farming practices, which may damage nesting sites. These findings provide important guidelines for the use of agricultural practices, and emphasize the need for the adoption of effective strategies for the conservation and sustainable management of the populations of these potentially beneficial insects. KEY-WORD: Conservation, hymenopterans, agroecosystems. RESUMO: As vespas contribuem para a qualidade ambiental e os serviços ecossistêmicos e desempenham um papel fundamental no funcionamento de muitos ambientes. O presente estudo investigou a diversidade de espécies de vespas solitárias que ocuparam ninhos-armadilha em ambientes de cultivo, bem como a arquitetura dos ninhos encontrados. .. O estudo concentrou-se em três áreas de agroecossistema, onde foram instalados 30 blocos de ninhos-armadilha, com quatro diâmetros (5 mm, 7 mm, 9 mm e 11 mm). Um total de 56 ninhos foram ocupados por vespas solitárias, sendo as espécies mais freqüentes Trypoxylon sp.1, Crabronidae (N=100, 54,9%), Pachodynerus cf. Brevithorax, Vespidae (N=31, 17,0%), Trypoxylon sp.2, Crabronidae (N=27, 14,8%) e Caenochrysis nigropolita, Chrysididae (N=9, 4,9%). As vespas ocuparam preferencialmente os ninhos-armadilha de 5 mm e 7 mm de diâmetro. Seis famílias de vespas foram registradas, sendo as mais abundantes Crabronidae com 127 indivíduos, seguida da família Vespidae (N=36). O número reduzido de espécies registradas na área de estudo pode estar relacionado ao uso frequente de pesticidas e às práticas agrícolas, que podem danificar os locais de nidificação. Esses resultados fornecem alertas importantes para o uso de práticas agrícolas e enfatizam a necessidade de adoção de estratégias eficazes para a conservação e manejo sustentável das populações desses insetos potencialmente benéficos. PALAVRAS-CHAVE: Conservação, himenópteros, agroecossistemas.

Many insects, especially nocturnal insects, exhibit positive phototaxis to artificial lights. Light traps are currently used to monitor and manage insect pest populations, and play a crucial role in physical pest control. Efficient use of light traps to attract target insect pests is an important topic in the application of integrated pest management (IPM). Phototactic responses of insects vary among species, light characteristics and the physiological status of the insects. In addition, light can cause several biological responses, including biochemical, physiological, molecular and fitness changes in insects. In this review, we discuss several hypotheses on insect phototaxis, factors affecting insect phototaxis, insect-sensitive wavelengths, biological responses of insects to light, and countermeasures for conserving beneficial insects and increasing the effect of trapping. In addition, we provide information on the different sensitivities to wavelengths causing positive phototactic behavior in > 70 insect pest and beneficial insect species. The use of advanced light traps equipped with superior light sources, such as light-emitting diodes (LEDs), will make physical pest control in IPM more efficient. © 2019 Society of Chemical Industry.

Creating non-crop habitats for sustaining pollinators and other beneficial insects in agricultural landscapes has gained momentum in recent times. However, in the tropics, considering limited availability of land for non-crop habitat creation, it is critical to select right kind of non-crop plant species with floral traits that can attract pollinators in good number. We tried to understand bees’ preferences with respect to two important visual cues belonging to four common non-crop species (Sida acuta, Stylosanthes hamata, Limnophila repens, Tephrosia purpurea) in the study area. We grew these plants in pots and arranged them in 5 combinations based on flower colour and structure. Increased bee visitation was observed in flowers that had blue petals and in complex flowers (reproductive parts hidden). However, complex structure of the flower rather than petal colour was more important in attracting bees. This information will be crucial in making species choice for creation of non-crop habitats in the limited available spaces in the tropical agricultural landscape.

The results show that the orb-weaver spiders, Neoscona theisi and Cyrtophora citricola, occurred in both guava and citrus agroecosystems, and their prey primarily comprised a wide diversity of insect pests. In contrast, the sheet web-constructing social spider, Stegodyphus sarasinorum, occurred only in the citrus agroecosystem and preyed mainly on the beneficial insects, particularly the pollinators, including the Asian honeybee, Apis cerana, along with the predaceous ladybird beetle, Coccinella septempunctata, damselfly, Agriocnemis femina, and the ant, Camponotus compressus. Field observations revealed that the beneficial insects caught and captured by the social spiders comprised mainly the flower-visiting insects of ornamental and weed plants growing in the vicinity of the fruit trees. N. theisi preyed predominantly on pests of paddy (Nephotettix nigropictus, Oxya nitidula), wheat (Rhopalosiphum padi), citrus (Papilio demoleus) and guava (Bactrocera dorsalis) and to a lesser extent on damselflies, houseflies, and ants. C. citricola with smaller orb webs preyed upon N. nigropictus, R. padi, M. domestica, C. septempunctata, and C. compressus. Except the guava pest, B. dorsalis, the pests of paddy and wheat from the infested crops cultivated in the nearby ~ 500-m distant located farm were attracted by the streetlights and were preyed upon by the arboreal spiders. The results highlight the significant role of orb web spiders in the suppression of insect pests of crops and also provide direct evidence of the negative role of social spiders as predators of the Asian honeybee, A. cerana, and other beneficial insects.

Agricultural intensification is a key suspect among putative drivers of recent insect declines, but an explicit link between historical change in agricultural land cover and insect occurrence is lacking. Determining whether agriculture impacts beneficial insects (e.g. pollinators), is crucial to enhancing agricultural sustainability. Here, we combine large spatiotemporal sets of historical bumble bee and agricultural records to show that increasing cropland extent and decreasing crop richness were associated with declines in over 50% of bumble bee species in the agriculturally intensive Midwest, USA. Critically, we found that high crop diversity was associated with a higher occurrence of many species pre-1950 even in agriculturally dominated areas, but that current agricultural landscapes are devoid of high crop diversity. Our findings suggest that insect conservation and agricultural production may be compatible, with increasing on-farm and landscape-level crop diversity predicted to have positive effects on bumble bees.

Pollinators underpin global food production, but they are suffering significant declines across the world. Pesticides are thought to be important drivers of these declines. Herbicides are the most widely applied type of pesticides and are broadly considered ‘bee safe’ by regulatory bodies who explicitly allow their application directly onto foraging bees. We aimed to test the mortality effects of spraying the world's most popular herbicide brand (Roundup®) directly onto bumble bees Bombus terrestris audax. We used three Roundup® products, the consumer products Roundup® Ready‐To‐Use and Roundup® No Glyphosate, the agricultural product Roundup® ProActive, as well as another herbicide with the same active ingredient (glyphosate), Weedol®. Label recommended pesticide concentrations were applied to the bees using a Roundup® Ready‐To‐Use spray bottle. Bees exhibited 94% mortality with Roundup® Ready‐To‐Use® and 30% mortality with Roundup® ProActive®, over 24 hr. Weedol® did not cause significant mortality, demonstrating that the active ingredient, glyphosate, is not the cause of the mortality. The 96% mortality caused by Roundup® No Glyphosate supports this conclusion. Dose‐dependent mortality caused by Roundup® Ready‐To‐Use, further confirms its acute toxicity. Roundup® products caused comprehensive matting of bee body hair, suggesting that surfactants, or other co‐formulants in the Roundup® products, may cause death by incapacitating the gas exchange system. These mortality results demonstrate that Roundup® products pose a significant hazard to bees, in both agricultural and urban systems, and that exposure of bees to them should be limited. Synthesis and applications. Surfactants, or other co‐formulants, in herbicides and other pesticides may contribute to global bee declines. We recommend that, as a precautionary measure until co‐formulant identities are made public, label guidelines for all pesticides be altered to explicitly prohibit application to plants when bees are likely to be foraging on them. As current regulatory topical exposure toxicity testing inadequately assesses toxicity of herbicide products, we call for pesticide companies to release the full list of ingredients for each pesticide formulation, as lack of access to this information hampers research to determine safe exposure levels for beneficial insects in agro‐ecosystems.

Management of agricultural pests requires an understanding of pest species diversity, their interactions with beneficial insects and spatial-temporal patterns of pest abundance. Invasive and agriculturally important insect pests can build up very high populations, especially in cropping landscapes. Traditionally, sampling effort for species identification involves small sample sizes and is labour intensive. Here, we describe a multi-primer high throughput sequencing (HTS) metabarcoding method and associated analytical workflow for a rapid, intensive, high-volume survey of pest species compositions. We demonstrate our method using the taxonomically challenging Bemisia pest cryptic species complex as examples. The whiteflies Bemisia including the ‘tabaci’ species are agriculturally important capable of vectoring diverse plant viruses that cause diseases and crop losses. Our multi-primer metabarcoding HTS amplicon approach simultaneously process high volumes of whitefly individuals, with efficiency to detect rare (i.e., 1%) test-species, while our improved whitefly primers for metabarcoding also detected beneficial hymenopteran parasitoid species from whitefly nymphs. Field-testing our redesigned Bemisia metabarcoding primer sets across the Tanzania, Uganda and Malawi cassava cultivation landscapes, we identified the sub-Saharan Africa 1 Bemisia putative species as the dominant pest species, with other cryptic Bemisia species being detected at various abundances. We also provide evidence that Bemisia species compositions can be affected by host crops and sampling techniques that target either nymphs or adults. Our multi-primer HTS metabarcoding method incorporated two over-lapping amplicons of 472bp and 518bp that spanned the entire 657bp 3’ barcoding region for Bemisia, and is particularly suitable to molecular diagnostic surveys of this highly cryptic insect pest species complex that also typically exhibited high population densities in heavy crop infestation episodes. Our approach can be adopted to understand species biodiversity across landscapes, with broad implications for improving trans-boundary biosecurity preparedness, thus contributing to molecular ecological knowledge and the development of control strategies for high-density, cryptic, pest-species complexes.

Aphids are one of the most economically important pests to California’s Central Coast lettuce industry. Aphids vector the lettuce mosaic virus and are crop contaminants in the packaging of the product. Lettuce aphid, Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae), is one of the predominant aphid species in lettuce, and it poses unique management challenges forming colonies inside the lettuce head. Current management practices rely on repeated foliar insecticide applications to reduce aphid densities per plant. Some organic growers have explored the release of laboratory-reared beneficial insects to manage aphids in their commercial fields. This project sought to document the effects of drone-released lacewing eggs on lettuce aphid densities in organic romaine lettuce fields. Commercially reared lacewing eggs were released at a rate of 74,131 eggs/ha and organic-certified insecticides were sprayed following their respective label recommendations. Our results could be interpreted as preliminary evidence that drone release of lacewings could reduce aphid densities (15.6–150.0 aphids/lettuce head) when compared to the untreated plots (32.1–257.9 aphids/lettuce head). Aphid densities were also decreased after the application of foliar organic-certified insecticides (11.77–143.5). Traditionally, the cost of labor has limited the use of beneficials in the lettuce production system, but the use of drones for these releases may make this strategy more attractive. Based on our calculations, spraying an organic-certified insecticide is less expensive (direct operational costs of U.S. $ 116.36/ha) than releasing beneficial insects by hand ($ 185.40) or by drone ($ 176.00) when mimicking the conditions of this study.

Local knowledge on entomofauna influences environmental actions, particularly management practices, which can be sustainable or unsustainable. A farmer’s decision about which practice to adopt is associated with their knowledge of beneficial insects and pests. This study aimed to assess local knowledge of entomofauna in relation to associated management practices, within a context of socio-cultural and environmental change. Research was carried out in Santa Lucia, a small mestizo village located in the deforestation frontier of the Peruvian Amazon. Mestizos are migrants, or descendants of migrants, from non-Amazonian regions of Peru. First, freelistings were conducted with a group of 19 women and 25 men farmers to evaluate their theoretical knowledge of insects, and to select the most salient insects associated with cassava, maize and plantain. Second, two focus groups (with women and men separate) evaluated the practical knowledge of management practices for the most salient insects in the context of climate change. The most salient insects were collected and identified to the minimum possible taxonomic level. The results showed that farmers have a negative perception of entomofauna associated with cassava, maize and plantain, as they considered insects to be harmful to their staple crops. Most farmers are not aware of the importance of beneficial insects such as pollinators and natural enemies. The findings of the study further showed that mestizo farmers did not have any management practices to preserve beneficial entomofauna, half of the insects they regarded as pests did not present any associated management practices , and the other half applied both sustainable (preventive and curative) and unsustainable practices (e.g. use of pesticides). The paper further discusses the dynamics of mestizo local knowledge on entomofauna in a changing environment; and concludes that local capacities should be built to enrich the knowledge on the recognition, biology, and ecological role of entomofauna (e.g. pollination, natural predation), and associated management practices (e.g. agroecological preventive practices that decrease pest incidence and protect pollinators, instead of curative practices) as an adaptation strategy to climate change.

Bees and other beneficial insects experience multiple stressors within agricultural landscapes that act together to impact their health and diminish their ability to deliver the ecosystem services on which human food supplies depend. Disentangling the effects of coupled stressors is a primary challenge for understanding how to promote their populations and ensure robust pollination and other ecosystem services. We used a crossed design to quantify the individual and combined effects of food resource limitation and pesticide exposure on the survival, nesting, and reproduction of the blue orchard bee Osmia lignaria . Nesting females in large flight cages accessed wildflowers at high or low densities, treated with or without the common insecticide, imidacloprid. Pesticides and resource limitation acted additively to dramatically reduce reproduction in free-flying bees. Our results emphasize the importance of considering multiple drivers to inform population persistence, management, and risk assessment for the long-term sustainability of food production and natural ecosystems.

We have demonstrated how management of key orchard pests including the insect invasive species Halyomorpha halys (Stal) (Hemiptera: Pentatomidae) can be accomplished using a systems-level approach termed IPM-CPR (Integrated Pest Management-Crop Perimeter Restructuring) in apple. We conducted on-farm comparisons of IPM-CPR to standard management program for managing H. halys, Cydia pomonella (L.) (Lepidoptera: Tortricidae), Grapholita molesta (Busck) (Lepidoptera: Tortricidae), and Lygus lineolaris Palisot de Beauvois (Hemiptera: Miridae) in commercial apple orchards in 2014, 2016, and 2017 in New Jersey, Maryland, and Virginia. The presence and abundance of key pests and fruit injury at harvest were used as a measure of success of the program. We compared the amount of insecticide applied for each management program. In majority of instances, there were no differences in the IPM-CPR and the standard management program in terms of H. halys numbers in baited pyramid traps and stink bug injury at harvest. Damage from C. pomonella and G. molesta in the IPM-CPR treatment was significantly lower than the standard management program in 2014 and 2017. Amount of active ingredient used was on average 62.1% lower in the IPM-CPR treatment compared with standard management program. Despite a reduction in insecticide use, there were minimal impacts on beneficial insects. Overall, IPM-CPR in apples successfully managed key orchard pests, including H. halys, and used significantly less insecticide than a standard insecticide-based management program and could be adopted as a systems-level approach for pest population reduction. USDA CPPMUnited States Department of Agriculture (USDA) [2015-70006-24282] The authors are grateful to Ann Rucker, for her enormous assistance in the field work. We also express our gratitude to our research interns Nicholas Serata, Meghin Rollins, Christina Little, Marina Perez, and Nicolas Avila at Rutgers University for their assistance in field work and fruit injury assessment. We thank David Schmidt for his assistance in compilation of insecticide records from cooperative growers. We also thank our collaborators, especially those in Virginia and USDA, namely John Cullum, Nate Brandt, Lee Carper, and Chris Hott, who provided various technical assistance to the work. All the cooperators who made available their farms are very much acknowledged. This research was supported by USDA CPPM #2015-70006-24282. Public domain – authored by a U.S. government employee

Simple Summary Plants often increase their odor emissions after herbivore feeding damage, which in turn attract natural enemies of the herbivores such as insect predators. Synthetic versions of these so-called herbivore-induced plant volatiles (HIPVs) can be used to monitor populations of beneficial insects in agriculture. In addition, HIPVs can potentially attract the herbivores themselves. However, whether synthetic HIPVs interact with color to affect insect communities in farms is unknown. In this study, we tested a lure containing the HIPV methyl salicylate (named ‘PredaLure’) in combination with five different colored sticky traps to monitor insect populations in cranberry fields (also known as bogs). We found that hoverflies (also called flower flies or syrphid flies), whose larvae are predators of several insect pests including aphids and thrips, were attracted to PredaLure but this attraction was affected by the color of the trap. In fact, the numbers of hoverflies were 2–4 higher on yellow and white traps baited with PredaLure than on unbaited traps. Irrespective of trap color, plant-feeding thrips were also more attracted to PredaLure-baited than unbaited traps. Our study provides guidelines for the use of odor-baited colored sticky traps to monitor natural enemies such as hoverflies in an agricultural system like cranberries. Abstract Synthetic herbivore-induced plant volatiles (HIPVs) could be used to monitor insect populations in agroecosystems, including beneficial insects such as natural enemies of herbivores. However, it is unknown whether insect responses to HIPVs are influenced by visual cues, e.g., color. We hypothesized that the HIPV methyl salicylate (MeSA) interacts with color to affect insect captures on sticky traps. To test this, we conducted a 5 × 2 factorial field experiment in a commercial cranberry farm to monitor numbers of insect predators, parasitoids, and herbivores by using five colored sticky traps that were either baited with a MeSA lure (named ‘PredaLure’) or unbaited. At the community level, PredaLure increased captures of predators. At the individual-taxon level, captures of the hoverfly Toxomerus marginatus (Diptera: Syrphidae) and thrips (Thysanoptera: Thripidae) were higher on PredaLure-baited traps. However, only captures of T. marginatus on PredaLure-baited traps interacted significantly with color such that the numbers of this hoverfly on yellow and white traps were 2–4 times higher when baited with PredaLure. This study is the first to document the interactive effects of synthetic HIPVs and color on an insect community. Our findings have implications for optimal selection of HIPV-baited colored traps to monitor natural enemy populations in agroecosystems.

Biodiversity is decreasing dramatically worldwide with land use change and habitat degradation being among its major causes. In Europe, this biodiversity loss is strongly related to the intensification of agriculture which has led to the simplification of landscapes. This resulted in the homogenization of landscapes where only a few crops dominate, accompanied with an increase of field size. Natural and semi-natural landscape elements, such as hedgerows, vegetation strips and groves were withdrawn, while more and more grasslands were being cropped or abandoned. Yet, grasslands are important functional biodiversity providers for crops in agricultural landscapes, including species that can provide ecosystem services such as pest control or pollination to farming activities. This PhD thesis therefore aimed at disentangling the influence of field and landscape parameters on the arthropod communities of adjacent grasslands and croplands of agricultural landscapes. We sampled arthropods from pairs of neighboring cereal fields and grasslands in order to compare the field and landscape influences on the biodiversity of these two agricultural land cover types. Our research took place in three study regions of southeastern France, each of them representing a different gradient between annual winter cereal crops and permanent grasslands. We mainly focused on carabids, though we also studied to some extent ground-dwelling spiders as well as pollinators such as hoverflies and lacewings. The landscape parameters were based on a land cover recording of cropped, grasslands and (semi-)natural areas and linear elements 500 m around every sampled location.Concerning carabids, cropland and grassland assemblages remained mainly distinct, but they showed higher similarity when located closer, up to 4 km from each other. Carabid activity-density was higher in the study regions with higher grassland coverage. In grasslands, we found a higher species richness when the landscape diversity around was increased, except for the study region which was strongly dominated by grassland. In winter cereal crops, the landscape parameters showed no significant effect on carabid species richness. Moreover, the common species richness in neighboring cereal fields and grasslands was enhanced by higher density of field borders between these two land cover types in the studied landscapes. Though the land cover type was by far the major determinant of carabid traits, landscape parameters also had a significant influence. Polyphagous species tended more to be commonly appearing in neighboring grassland and cereal crop. Phytophagous species were highly exclusive to grasslands, while predatory were it in cereal crops.Regarding other arthropod groups, we observed that the spider family richness was higher in permanent grasslands, though there were more individuals caught in cereal fields. Both hover flies and lacewings sampled density were higher in cereal fields and lower in the neighboring of higher grassland coverage.This thesis indicates that the preservation and restoration of a mosaic of permanent grasslands within diversely cropped landscapes is important for functional biodiversity. The inclusion of grasslands can enhance the diversity of beneficial arthropods and provide complementary resource and habitats to communities for pest control in crops. ; La biodiversité connaît un déclin préoccupant à l’échelle mondiale, les modifications et dégradations des habitats en demeurent l’une des causes principales. En Europe, la perte de biodiversité est étroitement liée à l’intensification de l’agriculture, qui a conduit à la simplification des paysages. En a résulté l’homogénéisation des paysages, où une faible diversité de cultures domine, ainsi qu’un agrandissement des parcelles. Les éléments naturels et semi-naturels, tels que les haies, les bandes enherbées ou les bosquets, furent retirés, alors que les prairies permanentes furent mises en culture ou abandonnées. Les prairies sont pourtant essentielles pour la biodiversité auxiliaire, car elles abritent et favorisent des espèces qui peuvent fournir lutte biologique et pollinisation à l’agriculture. Cette thèse propose donc de distinguer les influences de la parcelle, locale, et du paysage sur les communautés d’arthropodes de prairies permanentes et de cultures céréalières avoisinantes.Nous avons échantillonné des arthropodes d’appariement de céréales et prairies voisines, afin de comparer les effets de paramètres locaux et paysagers sur les biodiversités de ces deux couvertures du sol typiques des paysages agricoles. Nous avons mené ces travaux dans trois territoires différents, tous situés en Auvergne Rhône-Alpes. Chaque territoire était représentatif d’un gradient d’équilibre différent entre les couvertures en cultures annuelles et prairies permanentes. Notre intérêt s’est principalement porté sur les carabes, bien que nous ayons aussi étudié, dans une moindre mesure, les araignées ainsi que des pollinisateurs volants tels que les syrphes et les chrysopes. Les paramètres paysagers ont été établis à partir d’un recensement manuel de toutes les couvertures du sol, cultivées ou naturelles, ainsi que des éléments linéaires dans un rayon de 500 m autour de chaque site échantillonné.Les assemblages de carabes dans les prairies et céréales étaient très distincts, même s’ils ont présenté plus de similarités quand ils étaient plus proches, dans des parcelles distantes jusqu‘à 4 km l’une de l’autre. L’activité-densité des carabes était supérieure dans les territoires où la couverture globale en prairies permanentes était plus importante. Dans les prairies, nous avons trouvé une plus grande richesse spécifique dans des contextes paysager plus diversifiés, à l’exception du territoire fortement dominé par des prairies. Nos analyses n’ont pas mis en évidence d’effet du paysage sur la richesse spécifique des carabes dans les céréales. Par ailleurs, la richesse spécifique commune aux deux couvertures du sol était plus importante dans des contextes paysagers où céréales et prairies partageaient plus de bordures ensemble. Bien que le type de couverture du sol fût un facteur majeur dans la détermination des traits de vie des carabes, les paramètres paysagers eurent aussi leur importance. Ainsi, les espèces polyphages furent les plus sensibles d’être échantillonnées à la fois dans des prairie et céréale appariées. Les espèces phytophages ont ainsi été très souvent exclusivement échantillonnées dans les prairies, alors que les prédatrices l’étaient dans les céréales.Concernant les autres arthropodes, nous avons observé une plus grande richesse en familles d’araignées dans les prairies, bien qu’elles présentassent plus d’individus dans les céréales. Le nombre de syrphes et de chrysopes échantillonnés était plus important dans les céréales, et négativement influencé par la couverture paysagère en prairies.Notre thèse indique qu’il serait utile de préserver et restaurer une mosaïque de prairies permanentes dans les paysages agricoles diversifiés. Les prairies peuvent en effet améliorer la diversité auxiliaire des arthropodes et procurer des ressources complémentaires à leurs communautés.

Carabids (ground beetles) are important beneficial insects that contribute to biological control of pests and weeds in crop production. They can be found in different agricultural landscape habitats. However, little has been studied about the composition and similarity of carabid assemblages between two major land covers types: cropland and grassland. In a context of declining grassland areas in farmlands, highlighting complementarities of these two land covers is crucial to encourage land use planning that favors biodiversity. The objective of this study was to evaluate the relative and shared contribution of cereal crops and grasslands to carabid diversity in farmlands. Carabids were sampled in 104 pairs of cereal fields and grasslands in 3 agricultural regions of southeastern France. Carabid diversity was further analyzed with multiple regression models, including different local parameters. The correlations between assemblage similarities and geographical distance of sampled cereal fields and grasslands were also studied. Overall, 115 different species were found, 82 in cereal fields and 95 in grasslands. Per site species number and activity-density were higher in the two study regions with higher grassland cover. Evenness of carabid assemblages were higher in grasslands. Cropland and grassland remained strongly distinct, but assemblages showed higher similarity up to 4 km distance from each other. The study illustrates the major interest in preserving grassland within farmland for land use planners and/or policy makers. We found that grasslands and croplands complement each other. Though they host distinct communities, they provide continuous and different resources to the species throughout the year.

Organic vegetable farmers rely heavily on labor-intensive tillage for weed management, which adversely affects soil health and harms beneficial insects that consume crop pests and weed seeds. Using cover crop residues as a weed-suppressive mulch enables some reduction in tillage, and combining this tool with recently developed organic herbicides may further enhance weed suppression in vegetable production. However, organic herbicides may also adversely affect beneficial insects, and their nontarget effects are unknown. Here, we examine the combined impacts of cultural and chemical tools on weed cover while monitoring activity of beneficial epigeal insects and measuring rates of weed seed biological control to assess potential nontarget effects of organic herbicides. In a 2-yr experiment, we compared three cover crop mulch treatments and three organic herbicide treatments (capric/caprylic acid, corn gluten meal, and herbicide-free) in a reduced-tillage system. Organic herbicides led to no reductions in beneficial insect activity nor weed seed biocontrol. In both years, capric/caprylic acid herbicide and cover crop mulches reduced weed pressure relative to a fallow control treatment, whereas corn gluten meal had no effect. In year 2, a combination of cover crop mulch with organic herbicide had the greatest weed suppression relative to the fallow control. Integrated weed management is a perpetual challenge, but our results suggest that organic herbicides used in concert with cover crop mulch may enhance weed control and reduce the need for tillage, with limited collateral damage to natural enemies.

Conservation practices in agriculture—such as biological pest control, provision of pollinator habitat and cover cropping—may provide ecosystem services that are beneficial to both farmers and wildlife. Despite these benefits, however, their use is not yet widespread and the factors that may limit adoption are not well-understood. In this study we tested potential associations between farmers' beliefs about ecosystem services and their management practices using data collected from questionnaires and cognitive maps from 31 Michigan blueberry and cherry farmers describing their farming systems. We found that farmers who included key biological pest control concepts in their mental model representations reported the use of more conservation practices, and/or participation in conservation programs, than those who did not. In addition, the timing of management practices was a more central factor in the mental models of farmers who included both natural predators and beneficial insects than those omitting these factors. Finally, the farmers who included those two factors showed higher degrees of systems thinking based on mental model metric analysis. We suggest that outreach emphasizing the relationships between ecosystem services and the factors farmers view as most important may positively influence communication and potential of adoption of conservation practices and preventative pest management strategies.

Syahidah T, Rizali A, Prasetyo LB, Pudjianto, Buchori D. 2020. Short Communication: Landscape composition alters parasitoid wasps but not their host diversity in tropical agricultural landscapes. Biodiversitas 21: 1702-1706. The diversity of parasitoid wasps and their hosts in an agricultural landscape is affected by crop management and habitat conditions around crop fields. The composition of agricultural landscapes that are dominated by non-crop or natural habitats are assumed to be able to support the presence of parasitoid wasps as biological control of pests. The aim of this study was to investigate the effect of landscape composition on the diversity of parasitoid wasps and their hosts in agricultural landscapes. The research observations were conducted on six fields of long-bean cultivation located in Bogor District, West Java Province, Indonesia. Parasitoid wasps were collected by hand-collecting of their hosts (lepidopteran larvae) within 60 m distance transect to each long-bean field. In total, 17 species of parasitoid wasps and 12 species of lepidopteran larvae were found from all agricultural landscapes. A parasitoid wasp, Microplitis manilae was found in all long-bean fields (except Bantarjaya) and only parasitized the tobacco cutworm (Spodoptera litura). The tomato looper, Chrysodeixis chalcites had the highest associated parasitoids and was also parasitized by Braconidae sp5 which was also a parasitoid of S. litura. Based on the analysis results, the patch numbers of natural habitats had a positive effect on the diversity of parasitoid wasps and had no effect on the diversity of lepidopteran larvae. In conclusion, landscape compositions with patchy natural habitats have an important role to preserve beneficial insects and maintain ecosystem services in tropical agricultural landscapes.

Frequent extreme weather events, which jeopardize agriculture by affecting crop health, characterize the ongoing climate change. Temporary patches where sown plants are poorly developed (hereafter “field defects”) are likely to increase with climate change and can be colonized by other plant species. Although perennial non-crop habitats can act as refuges for beneficial insects in agricultural landscapes and increase ecosystem services (ESs) in neighbouring arable fields, the relevance of field defects is unknown. Here, we quantified two ESs (pest and weed seed predation) in field defects within oilseed rape crops and related the ES levels with the activity-density of ground beetles and temperature. In 10 fields, we used artificial caterpillars made of plasticine and seed cards of two weed species (Taraxacum sp. and Stellaria sp.) to quantify the ESs in two sampling periods (spring and summer) and three habitat types: field defects, crops grown in standard conditions (field interiors) and crop-defect boundaries. Ground beetles were sampled using pitfall traps and classified into feeding guilds and body-size classes. Insects and mammals were the main pest predators, and predation increased in summer but did not differ among habitats. Seed predation rates for both species were significantly higher in summer. Predation upon Taraxacum seeds was higher in the field interiors, whereas the predation rate upon Stellaria seeds was significantly higher in the field interiors and defects compared to that in the crop-defect boundaries. The predation rate by insects increased with the activity-density of the medium- and large-sized carnivorous carabids, whereas the seed predation rate for both weed species was positively related to the activity-density of medium-sized herbivorous carabids. Finally, the mean and maximum temperatures were negatively linked to the predation rates on artificial caterpillars and seeds of Taraxacum, respectively. Our results suggest that these ephemeral habitats are not related to a strong decrease in ecosystem services; thus, field defects may not cause substantial changes in ES provisioning. We confirmed that ground beetles are important providers of both investigated ESs and showed that microclimatic conditions might play an important role in the regulation of ESs in agroecosystems. Grant Agency of the Czech Republic (18-26542S); Faculty of Environmental Sciences, Czech University of Life Sciences Prague (IGA) (42110/1312/3118) info:eu-repo/semantics/publishedVersion

Aguero, J.I., Rollin, O., Torretta, J.P., Aizen, M.A., Requier, F., Garibaldi, L.A. 2018. Honey bee impact on plants and wild bees in natural habitats. Ecosistemas 27(2): 60-69. Doi.: 10.7818/ECOS.1365 The honey bee (Apis mellifera L.) has been spread all over the world by humans and is now the most widespread bee invasive species. In spite of being considered a beneficial species, there is a controversy around its impact on natural habitats caused by its high densities. Here we review the most important effects and mechanisms attributed to an increase in honey bee abundance on plants and wild bees. We found that the impacts can be negative and positive as well, playing an important role the ecological context (resource availability, wild pollinator community, etc.) and the honey-bee density. Effects occur at the individual, population, and community level, affecting plant-pollinator networks, while the consequences for ecosystem functioning and crop pollination are still uncertain. It has been recently shown that the honey bee can also act as a selective force affecting plant evolution in a relative short time. The parasite and pathogen transmission from honey bees to wild pollinators has become a relevant issue in the last years. Although honey bees can benefit wild plants pollination, because impacts in other bees are primary negative, we should be careful with hives introduction at natural sites. Especially until we can determine the parasites and pathogen transmission consequences.

Switchgrass (Panicum virgatum) and a mix of native warm season grasses with forbs (NWSG-mix) have received attention as cellulosic biofuel sources. While numerous studies support greater biodiversity within those biofuel crops than corn, it is unclear how switchgrass and NWSG-mix affect beneficial insects such as pollinators (PO) and predators/parasites/parasitoids (PPP). Also, few empirical studies have explored the effects of biofuel crop harvest on insects. We investigated the responses of PO and PPP insects to those two biofuel crops and harvest frequency in Mississippi, USA, during 2011–2013. We established 16 fields on agricultural lands and randomly assigned each one of 4 treatments: switchgrass with single harvest; switchgrass with multiple harvests; NWSG-mix with single harvest; NWSG-mix with multiple harvests. We set up 3 sampling stations per field and conducted insect sampling 1–3 times monthly during summer to fall using colored pan traps. We tested treatment effects with general linear mixed models and redundancy analyses. While treatment effects varied by season and year, biofuel crop type influenced abundance and insect family diversity but harvest frequency did not. During summer, total abundance and guild-level (PO and PPP) abundance were high in switchgrass in 2011. During fall, total abundance and abundance of PPP were high in NWSG-mix in 2011 and 2012 and abundance of PO in 2011 and 2013. Family richness was also greater in NWSG-mix across seasons in 2011 and 2012 and during fall in 2013. More families tended to be associated with NWSG-mix than switchgrass. Our results suggest that 1) biofuel crop type is a more important factor influencing beneficial insects than harvest frequency and 2) compared to NWSG-mix, switchgrass may provide more resources for insects during summer or during the first year after establishment; however, NWSG-mix could enhance insect diversity and abundance of pollinators for a longer period of time.

The parasitoid communities in organic and integrated pest management (IPM) kiwifruit orchards have previously been found to differ significantly, but we do not know if this affects the quality or quantity of biocontrol services. We compared parasitism of two leafroller (Lepidoptera: Tortricidae) pest species, Ctenopseustis obliquana (Walker) and Cnephasia jactatana (Walker), in the two types of orchard. Within each orchard, we focussed on a large shelterbelt between the kiwifruit vines and an alternative land-use to also investigate whether the shelterbelts and neighbouring habitat were a source of pests or beneficial insects for these orchards. Sentinel larvae were used to determine both parasitoid identity and parasitism rate each month during the kiwifruit growing seasons in 2013/14 (16 orchards) and 2014/15 (12 orchards). The numbers of Tortricidae and parasitoids in the shelterbelt on each orchard in each month was also assessed in 2014/15. Four parasitoid species emerged from the sentinel larvae, although average parasitism rates were very low (1–3%). There were no detectable effects of orchard management, shelterbelt type or neighbouring land-use on parasitism rates. Parasitoid numbers were low in all orchards in 2014/15, although more parasitoids were collected from the IPM orchards than the organic ones. This may have been in response to the increasing numbers of Tortricidae in the shelterbelts on the IPM orchards during the season, a trend that was not observed in the organic orchards. Both shelterbelt composition and neighbouring land-use were found to affect total combined counts of Tortricidae and parasitoids, with higher counts in shelterbelts composed of Cryptomeria japonica and where adjacent land contained native bush or tree-based scrub. Each may therefore be a source of both taxa for the orchards. Modifications to the shelterbelts that increase parastoids but not Tortricidae are needed.

On the Ground • Grasshopper outbreaks in Nebraska have resulted in losses over $2 million per year due to lost forage for livestock. As much as 23% of western U.S. forage is consumed by grasshoppers annually. • Controlling grasshoppers reduced grasshopper numbers without negatively impacting beneficial insects. • In 2011, 29 more 318 kg steers could have grazed a 1000 hectare pasture for a 5 month growing season due to grasshopper suppression. In 2012 (a drought year), 54 more steers could have been grazed if grasshoppers were controlled. Grasshopper infestation can result in significant reduction in livestock grazing capacity especially in dry conditions.

Neonicotinoid insecticides are currently the fastest-growing and most widely used insecticide class worldwide. Valued for their versatility in application, these insecticides may cause deleterious effects in a range of non-target (beneficial) arthropods. However, it remains unclear whether strong patterns exist in terms of their major effects, if broad measures of arthropod performance are negatively affected, or whether different functional groups are equally vulnerable. Here, we present a meta-analysis of 372 observations from 44 field and laboratory studies that describe neonicotinoid effects on 14 arthropod orders across five broad performance measures: abundance, behavior, condition, reproductive success, and survival. Across studies, neonicotinoids negatively affected all performance metrics evaluated; however, magnitude of the effects varied. Arthropod behavior and survival were the most negatively affected and abundance was the least negatively affected. Effects on arthropod functional groups were inconsistent. Pollinator condition, reproductive success, and survival were significantly lower in neonicotinoid treatments compared to untreated controls; whereas, neonicotinoid effects on detritivores were not significant. Although magnitude of arthropod response to neonicotinoids varied among performance measures and functional groups, we documented a consistent negative relationship between exposure to neonicotinoid insecticides in published studies and beneficial arthropod performance.

Understanding beta-diversity, i.e. species turnover in space and time, is essential for informing conservation actions. Soaring cultivation of mass flowering crops (e.g. oil seed rape OSR) and loss of semi-natural habitats (SNH) can strongly affect populations of native pollinators, yet it remains unclear how OSR and SNH affect spatial and temporal turnover of pollinator communities. Here, we examined how the landscape-scale proportions of OSR and SNH affect spatial and temporal community turnover in solitary bees and hoverflies, two key provider groups of pollination and pest control services in temperate agro-ecosystems. Using a novel grid-based landscape-wide sampling approach, we quantified pollinator communities within ten 1 km × 1 km landscapes representing independent gradients in OSR and SNH availability. We sampled during and after OSR flowering, in two subsequent years, yielding app. 8800 specimens representing 160 species. Spatial community turnover, measured as the slope of the dissimilarity-distance relationship, was not influenced by the proportion of OSR at any time. In contrast, SNH decreased community turnover for bees during OSR flowering and for hoverflies after flowering, likely caused by pollinator movement between land use types. This suggests that a high availability of SNH may help to promote an even distribution of native bees and hoverflies within temperate agricultural landscapes, hereby potentially stabilizing landscape-wide pollination services.

Experimental approaches to studying the consequences of pesticide use, including impacts on beneficial insects, are vital; however, they can be limited in scale and realism. We show that an ecoinformatics approach that leverages existing data on pesticides, pests, and beneficials across multiple fields can provide complementary insights. We do this using a multi-year dataset (2002-2013) on pesticide applications and density estimates of two pests, citrus thrips (Scirtothrips citri (Moulton [Thysanoptera: Thripidae])) and citrus red mites (Panonychus citri McGregor [Acari: Tetranychidae]), and a natural enemy (Euseius spp. predatory mites) collected from citrus groves in the San Joaquin Valley of California. Using correlative analyses, we investigated the long-term consequences of pesticide use on S. citri and P. citri population densities to evaluate the hypothesis that the pest status of these species is largely due to the disruption of natural biological control-i.e., these are induced pests. We also evaluated short-term pesticide efficacy (suppression of citrus thrips and citrus red mite populations immediately post-application) and asked if it was correlated with the suppression of Euseius predator populations. Although the short-term efficacy of different pesticides varied significantly, our dataset does not suggest that the use of citrus pesticides suppressed Euseius densities or worsened pest problems. We also find that there is no general trade-off between pesticide efficacy and pesticide risk to Eusieus, such that highly effective and minimally disruptive compounds were available to citrus growers during the studied time period.

Berry crops are increasingly produced in high tunnels, which provide growers with the opportunity to extend their production season. This is particularly beneficial for the northern region of the United States with short and unpredictable growing seasons and where rainfall limits fruit quality. However, little is known about the effect of high tunnels on the community of pests, natural enemies, or pollinators, especially in berry crops, and there are few reports of the insect community in raspberries in this region. We compared the abundance of these insects during two growing seasons in field-grown and tunnel-grown floricane and primocane producing raspberries through direct observation and trapping at five sites in southwestern and central Michigan. We found eight key pests, including spotted wing Drosophila, leafhoppers, and thrips, and seven key natural enemies including parasitoid wasps, spiders, and lacewings, that were common across all sites. Pest populations were up to 6.6 times higher in tunnels, and pests typical of greenhouse systems became more dominant in this environment. Natural enemies observed on plants under tunnels were also more abundant than in the field, but this trend was reversed for natural enemies trapped on yellow sticky cards. There was also a reduction of both honey bees and wild bees under the high tunnels, which was balanced by use of commercial bumble bees. These data not only provide much-needed information on the phenology of the insect community on raspberry plantings, they also highlight the entomological implications of protected raspberry culture.

Soybean, the main crop of Argentina, has promoted spatial and temporal homogenization of the agricultural landscape accompanied by significant losses of biodiversity, along with increases in the use of chemical inputs. One of the possible solutions to overcome these effects is the diversification of the agroecosystem, avoiding the control of weed species that could act as attractants of beneficial insects and deterrents of herbivory, without compromising crop yield. The aims of this work were to evaluate the composition, abundance and richness of insect assemblages in different soybean-weed (Artemisia annua and Chenopodium album)-herbivory combinations and to determine the relationship between insect assemblages and volatile signals emitted by the different combinations. Two factorial experiments were conducted during two consecutive seasons under field conditions. Factors were: i) crop-weed combinations with five levels: pure soybean (PS), soybean + 2 A. annua plants m−2 (2A), soybean + 4 A. annua plants m−2 (4A), soybean + 2 C. album plants m−2 (2C) and soybean + 4 C. album plants m−2 (4C) and ii) herbivory with two levels: with (+H) and without (−H). Volatile signals were measured with an electronic nose and insects were sampled with pitfall traps located in the center of each plot. Different insect assemblages related to treatments were identified. Richness increased when soybean was accompanied by weeds. The proportion of non-herbivores was always higher than that of herbivores. In both seasons, the same sensors detecting volatile cues were the main explanatory variables of the insect data, being responsible for the separation of A. annua treatments from the others. Many non-herbivore species were attracted to A. annua and repelled by signals captured by these sensors and, on the contrary, many herbivore and non-herbivore species were attracted to those blends associated to PS and C. album. PS and C. album could represent a food source for herbivores and alternative food or host for non- herbivores. Herbivory was not a discriminant explanatory variable. This work highlights that insect assemblage varies according to different crop-weed combinations and their volatile signals. Considering the positive impact on insect diversity of some species currently considered as weeds, could be useful to design future agro-ecosystems in which the regulation of pests is accomplished by increasing the fauna of beneficial insects and, thus, reducing the use of pesticides.

Paved roadways, spanning 6.6 million kilometres across the continental United States, are often bordered by natural or restored habitats and could provide opportunities for pollinator conservation. Because insects are frequently killed by auto traffic, roadside habitats may be ecological traps that kill more pollinators than they produce. Here we compare insect traffic mortality when roadsides are bordered by woodlots, meadows, or lawns. We also compare study sites with and without restored medians to examine the impact of creating habitat that can only be accessed by crossing traffic. We confined our study to high speed roads (70–90 km h−1) with heavy traffic volume. Both habitat type and the presence of a vegetated median affect vehicle strikes fatal to insects. Insect mortality in general, and its effect on bees and butterflies in particular, was consistently lower when roads were bordered by woodlots than when they were bordered by lawn or meadows. Which roadside habitats were associated with the highest insect mortality depended on the taxon in question and the presence or absence of a vegetated median. Butterfly and dragonfly mortality was highest on roads with meadow medians, while bee mortality was highest on roadsides with lawn medians. Across most site comparisons, vegetated medians significantly elevated fatal insect-vehicle strikes. Regardless of the habitat bordering roadsides, insect mortality was unacceptably high for areas being considered for conservation. We suggest four research directions that may lead to reduced insect mortality in roadside habitats.

The benefits of farming organically in the USA are increasingly known; however, organic farmers also encounter considerable risks, especially from weeds. Without herbicides, organic farmers can rely only on crop rotations, mechanical cultivation, manual weeding, beneficial insects and other cultural practices, termed ecological weed management (EWM), to control weeds. Despite promising results and the many ways in which EWM can be employed, it remains poorly adopted by the organic community. Organic farmers resist research and recommendations from University scientists and Extension, instead preferring to rely on local family and friends and their own experience to guide decisions. Here we investigate factors that may lead organic farmers to recognize that they need additional information about EWM and to seek that information out. Using a national survey of organic farmers (n = 554) and a risk-information seeking and processing model, we show that farmers’ risk and benefit perceptions, worry, social norms encouraging seeking out information, and farmers’ own perceived knowledge gaps, particularly with respect to their most problematic weed, influence information-seeking behavior. Identifying characteristics that may distinguish those organic farmers who need and want additional information, we provide recommendations to Extension and University scientists about how best to communicate, build trust and provide decision support to the organic community with respect to EWM.