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This report presents testing of a prototype cantilevered liquid-nitrogen-cooled silicon mirror. This mirror was designed to be the first mirror for the new soft X-ray beamlines to be built as part of the Advanced Light Source Upgrade. Test activities focused on fracture, heat transfer, modal response and distortion, and indicated that the mirror functions as intended. [ABSTRACT FROM AUTHOR]

Abstract: An understudied aspect of insecticides is their stress on non‐targeted pest species. Sublethal insecticidal stress may elicit a range of protective and non‐protective responses that may affect behaviour and sexual fitness of the exposed insects, which may lead to negative, neutral or stimulatory (i.e. hormetic) responses. We assessed the behavioural response of the Neotropical brown stink bug, Euschistus heros, a soybean pest in the Neotropical region with increasing pest status, following exposure to chlorantraniliprole, pyriproxyfen and spinosad, insecticides commonly used against soybean caterpillars and whiteflies. Both individuals, or only the male or female of each mating pair, were exposed. Reproductive behaviour and output were measured to determine insecticide‐ and gender‐mediated fitness. We found that treatment scenario significantly affected mating behaviour, and that the duration of some behaviours were significantly affected. Chlorantraniliprole and pyriproxyfen reduced latency to mate, while spinosad increased this behaviour. Insecticide exposure also decreased the interacting time of each couple and male antennation of the female. Fertility table analyses of exposed couples indicated negligible effect of pyriproxyfen exposure, while spinosad extended generation time and reduced net reproductive rate, leading to lower rates of population growth of the brown stink bug. In contrast, chlorantraniliprole led to only a slight extension on the generation time, but enhanced net reproductive rate of the stink bug leading to higher rates of population growth; no effects on sexual fitness were observed, as both compounds exhibited similar effect on females and males. Latency to mate correlated significantly with the population growth rate. The positive response to chlorantraniliprole exposure reinforces the notion that sublethal exposure of the brown stink bug to this insecticide may lead to stimulatory (hormetic) response favouring its outbreaks in soybean fields. [ABSTRACT FROM AUTHOR]

BACKGROUND Hormetic preconditioning, whereby exposure to mild stress primes an organism to better tolerate subsequent stress, is well documented. It is unknown if exposure to hormetic concentrations of insecticide can trans-generationally prime insects to better tolerate insecticide exposure, or whether exposure to hormetic concentrations of insecticide can induce mutations in genes responsible for insecticide resistance. Using the aphid Myzus persicae (Sulzer) and the insecticide imidacloprid as a model, we examined if exposure to mildly toxic and hormetic concentrations of imidacloprid reduced aphid susceptibility to insecticides across four generations, and whether such exposures induced mutations in the imidacloprid binding site in post-synaptic nicotinic acetylcholine receptors. RESULTS Chronic, multigenerational exposure of aphids to hormetic concentrations of imidacloprid primed offspring to better survive exposure to certain concentrations of imidacloprid, but not exposure to spirotetramat, an insecticide with a different mode of action. Exposure to hormetic and mildly toxic concentrations of imidacloprid did not result in mutations in any of the examined nicotinic acetylcholine receptor subunits. CONCLUSION Our findings demonstrate that exposure to hormetic concentrations of insecticide can prime insects to better withstand subsequent chemical stress, but this is dependent upon the insecticide exposure scenario, and may be subtle over generations. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Weeds are one of the most limiting factors in the commercial production of lowbush blueberries Vaccinium angustifolium ( Ericaceae). Sheep sorrel ( Rumex acetosella) and hairy fescue ( Festuca tenuifolia) are prominent weeds in lowbush blueberry fields., Because the granivorous insects Harpalus rufipes ( Carabidae) and Gryllus pennsylvanicus ( Gryllidae) are common in lowbush blueberry fields when sheep sorrel and hairy fescue are dispersing seeds, we examined how granivorous insects can contribute to the biocontrol of these weeds., In the laboratory, H. rufipes and G. pennsylvanicus consumed a significant number of seeds of sheep sorrel and hairy fescue, and a field experiment found that insects probably consume a significant number of sheep sorrel and hairy fescue seeds in blueberry fields., Additional experiments found that H. rufipes was highly susceptible to field rates of phosmet and acetamiprid, although not to field rates of spirotetramat, which are insecticides that may be used in blueberry fields when the beetle is active., Natural populations of granivorous insects probably provide a valuable ecological service in commercial lowbush blueberry fields and should be conserved in the development of integrated weed management programmes. [ABSTRACT FROM AUTHOR]

Horticultural practices may impact invertebrates in agroecosystems, particularly natural enemies. Impacts can be better understood by grouping organisms functionally or using morphological traits in addition to taxonomic determinations., We compared the effects of mulch type (compost, pine needles, unmulched) and weeding strategy (weeded, unweeded) on beetle (Coleoptera) communities in highbush blueberries, focusing on early-season captures that reflected overwintering habitat., Beetle diversity was similar between plot types, although functional grouping revealed differences as a result of mulching but not weeding. Predatory and granivorous Carabidae were most abundant in unmulched plots, mycetophages were most abundant in pine needles, and saprophages were most abundant in compost. Predatory Staphylinidae were most diverse in compost plots, and the diversity of granivores was greatest in unmulched plots., Carabid biomass was greater in unmulched than compost mulched plots partly as a result of larger beetle size., Beetle communities in unmulched and pine needles mulched plots were more similar than those in compost mulched plots., A combination of compost mulched and unmulched areas should benefit all predatory taxa, although mulch use for pest control will need to be evaluated within the context of other production goals. [ABSTRACT FROM AUTHOR]

ABSTRACT Global declines of bumble bees and other pollinator populations are of concern because of their critical role for crop production and maintenance of wild plant biodiversity. Although the consensus among scientists is that the interaction of many factors, including habitat loss, forage scarcity, diseases, parasites, and pesticides, potentially plays a role in causing these declines, pesticides have received considerable attention and scrutiny. In response, regulatory agencies have introduced more stringent pollinator testing requirements for registration and reregistration of pesticides, to ensure that the risks to pollinators are minimized. In this context, guidelines for testing bumble bees ( Bombus spp.) in regulatory studies are not yet available, and a pressing need exists to develop suitable protocols for routine higher-tier studies with these non- Apis sp., social bees. To meet this need, Bayer CropScience LP, Syngenta Crop Protection LLC US, and Valent USA. Corporation organized a workshop bringing together a group of global experts on bumble bee behavior, ecology, and ecotoxicology to discuss and develop draft protocols for both semi-field (Tier II) and field (Tier III) studies. The workshop was held May 8-9, 2014, at the Bayer Bee Care Center, North Carolina, USA. The participants represented academic, consulting, and industry scientists from Europe, Canada, the United States, and Brazil. The workshop identified a clear protection goal and generated proposals for basic experimental designs, relevant measurements, and endpoints for both semifield (tunnel) and field tests. These initial recommendations are intended to form the basis of discussions to help advance the development of appropriate protocol guidelines. Integr Environ Assess Manag 2016;12:222-229. © 2015 The Authors. Integrated Environmental Assessment and Management Published by SETAC [ABSTRACT FROM AUTHOR]

Several megachilid bees are excellent crop pollinators, and many species show potential for management as they nest in pre-existing cavities in artificial substrates. Some species, particularly in the Osmiini, however, have nesting habits not conducive to conventional trap-nesting. Here we report on an artificial nest for species of Osmia bees which normally build nests on the underside of stones., The Holarctic species Osmia inermis accepted overturned terracotta saucers as nesting sites, with 10% of the saucers occupied in the fall of 2011., These saucers are inexpensive and available in many sizes, facilitating further scientific study of this, and other species. Implications of using artificial nests for managing this bee for crop pollination, and for its conservation, are discussed. [ABSTRACT FROM AUTHOR]

BACKGROUND Blueberry maggot, Rhagoletis mendax Curran (Diptera: Tephritidae), is the most important pest of blueberries in eastern North America. Insecticide use in fruit-bearing lowbush blueberry fields could be reduced with management strategies focused on vegetative fields. Fly distribution and fruit infestation levels were assessed where fruit-bearing and vegetative fields adjoin and along forested edges of vegetative fields. RESULTS Along adjoining edges, immature female flies were captured in fruiting fields and mature females in vegetative fields throughout the season. Male fly captures and fruit infestation levels were greater at 5 m than at 30 m from the edge. Along forested edges, fly captures were best predicted by densities of ripe lowbush blueberries and large coniferous trees. Maggot infestation level in lowbush blueberries was best predicted by blueberry density and small deciduous trees. Bunchberry, Cornus canadensis L., was the only non-crop host in which blueberry maggot was found. CONCLUSIONS We have shown that relatively high numbers of flies occur in vegetative fields and at edges of fruiting fields. Ripe blueberries and certain vegetation in forested edges affect fly distribution and probably maintain populations. These results may help to predict where controls for blueberry maggot should be targeted and suggest that management strategies focused on vegetative fields and field edges may be worthwhile. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Ecological backlashes such as insecticide resistance, resurgence and secondary pest outbreaks are frequent problems associated with insecticide use against arthropod pest species. The last two have been particularly important in sparking interest in the phenomenon of insecticide-induced hormesis within entomology and acarology. Hormesis describes a biphasic dose-response relationship that is characterized by a reversal of response between low and high doses of a stressor (e.g. insecticides). Although the concept of insecticide-induced hormesis often does not receive sufficient attention, or has been subject to semantic confusion, it has been reported in many arthropod pest species and natural enemies, and has been linked to pest outbreaks and potential problems with insecticide resistance. The study of hormesis remains largely neglected in entomology and acarology. Here, we examined the concept of insecticide-induced hormesis in arthropods, its functional basis and potential fitness consequences, and its importance in arthropod pest management and other areas. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Neonicotinoid insecticides have been the target of much scrutiny as possible causes of recent declines observed in pollinator populations. Although neonicotinoids have been implicated in honey bee pesticide incidents, there has been little examination of incident report data. Here we summarize honey bee incident report data obtained from the Canadian Pest Management Regulatory Agency ( PMRA). RESULTS In Canada, there were very few honey bee incidents reported in 2007-2011 and data were not collected prior to 2007. In 2012, a significant number of incidents were reported in the province of Ontario, where exposure to neonicotinoid dust during planting of corn was suspected to have caused the incident in up to 70% of cases. Most of these incidents were classified as 'minor' by the PMRA, and only six cases were considered 'moderate' or 'major'. In that same year, there were over three times as many moderate or major incidents due to older non-neonicotinoid pesticides, involving numbers of hives or bees far greater than the number of moderate or major incidents suspected to be due to neonicotinoid poisoning. CONCLUSIONS These data emphasize that, while exposure of honey bees to neonicotinoid-contaminated dust during corn planting needs to be mitigated, other pesticides also pose a risk. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Insect pest management in wild blueberry ( Vaccinium angustifolium Aiton) usually involves insecticidal sprays, which may have detrimental effects on non-target beneficial insects. Dogbane beetle ( Chrysochus auratus Fabricius) (Coleoptera: Chrysomelidae) feeds almost exclusively on spreading dogbane ( Apocynum androsaemifolium L.), an increasing weed problem in wild blueberry production. Because C. auratus is an important natural enemy of spreading dogbane, we assessed its susceptibility to several insecticides it may be exposed to during insect pest management. In laboratory bioassays, we found adult dogbane beetles were highly susceptible to field rates of phosmet (Imidan) and acetamiprid (Assail) by direct topical contact and ingestion of treated foliage, whereas no mortality was seen with spirotetramat (Movento) and chlorantraniliprole (Altacor). Topical applications of spinetoram (Delegate) did not cause significant mortality of beetles, but high mortality to beetles was found when they ingested spinetoram-treated foliage. The results suggest that while some insecticides used in blueberry management will be hazardous to C. auratus, options are available that will cause little harm to this natural enemy. [ABSTRACT FROM AUTHOR]

BACKGROUND Pollinator exposure to pesticides is a concern in agricultural systems that depend on pollinators for crop production. However, not all pesticides elicit toxic effects, and response to a pesticide will vary depending on dose and exposure route. The effects of biopesticide formulations of Bacillus subtilis and Beauveria bassiana and of the tetramic acid insecticide spirotetramat on the common eastern bumblebee, Bombus impatiens, were evaluated. Microcolonies of bees were exposed to field-rate or lower concentrations, and data were collected over 60 days. RESULTS When ingested, field rates of spirotetramat caused high mortality after 10 days, and B. subtilis significantly reduced drone production, number of days to oviposition and number of days to drone emergence. Converse to effects observed following ingestion, topical applications of B. subtilis at concentrations less than the recommended field rate resulted in a hormetic response, with significantly increased drone production. Topical application of spirotetramat and oral or topical application of B. bassiana had no effects on bees. CONCLUSIONS Spirotetramat and B. subtilis can induce adverse effects on B. impatiens, but hormetic effects following B. subtilis treatment can also occur, depending on exposure route. Additional experiments are required to determine whether similar toxic or hormetic effects occur under more realistic field conditions. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The article studies the impact of exposure to sublethal concentrations of imidacloprid and azadirachtin on reproduction in green peach aphid, Myzus persicae. It is stated that Myzus persicae is an important insect pest of many crops that are exposed to sublethal insecticides concentrations. When the insects were exposed to potato leaf discs coated with sublethal concentrations of insecticide, almost all measured endpoints were affected. Thus, it was concluded that exposure to sublethal concentrations of imidacloprid and azadirachtin could stimulate reproduction in green peach aphid.

The acute and sublethal toxicities of novaluron, a novel chitin synthesis inhibitor, to a laboratory-reared insecticide-susceptible strain of Colorado potato beetle, Leptinotarsa deceinlineata (Say), were determined. Novaluron exhibited excellent residual (120 h LC50 = 0.42 mgliter-1) and good direct contact (120 h LC50 = 27 mglitre-1) activity against second-instar larvae (L2). Hatch of eggs exposed by direct contact to novaluron solutions ≥100 mg litre-1 was significantly reduced, as was the ability of emerged first-instar larvae to moult. L2 from eggs exposed to ≥100 mg litre-1 novaluron weighed significantly less (P ⩽ 0.0001) than those from untreated eggs. However, L2 from eggs treated with 1 mg litre-1 novaluron weighed significantly more (P ⩽ 0.05) than those from untreated eggs, suggesting novaluron can have a hormetic effect on L decemlineata larval development. Leptinotarsa decemlineata mating pairs fed foliage treated with novaluron at 25 or 75 g AI ha-1 produced approximately 25% fewer egg masses and eggs per mass. Hatch of eggs on treated foliage was almost completely suppressed, and longevity of male beetles was reduced by approximately 50% when fed foliage treated with novaluron at 75 g AI ha-1. [ABSTRACT FROM AUTHOR]

Hormesis, a biphasic dose response whereby exposure to low doses of a stressor can stimulate biological processes, has been reported in many organisms, including pest insects when they are exposed to low doses of a pesticide. However, awareness of the hormesis phenomenon seems to be limited among bee researchers, in spite of the increased emphasis of late on pollinator toxicology and risk assessment. In this commentary, we show that there are several examples in the literature of substances that are toxic to bees at high doses but stimulatory at low doses. Appreciation of the hormetic dose response by bee researchers will improve our fundamental understanding of how bees respond to low doses of chemical stressors, and may be useful in pollinator risk assessment. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]