550 research outputs found
Effects of reduced-risk pesticides and plant growth regulators on rove beetle (Coleoptera: Staphylinidae) adults
Citation: Echegaray, Erik R., and Raymond A. Cloyd. 2012. “Effects of Reduced-Risk Pesticides and Plant Growth Regulators on Rove Beetle (Coleoptera: Staphylinidae) Adults.” Journal of Economic Entomology 105 (6): 2097–2106. https://doi.org/10.1603/EC12244.In many regions, pest management of greenhouse crops relies on the use of biological control agents; however, pesticides are also widely used, especially when dealing with multiple arthropod pests and attempting to maintain high esthetic standards. As such, there is interest in using biological control agents in conjunction with chemical control. However, the prospects of combining natural enemies and pesticides are not well known in many systems. The rove beetle, Atheta coriaria (Kraatz), is a biological control agent mainly used against fungus gnats (Bradysia spp.). This study evaluated the effects of reduced-risk pesticides and plant growth regulators on A. coriaria adult survival, development, and prey consumption under laboratory conditions. Rove beetle survival was consistently higher when adults were released 24 h after rather than before applying pesticides. The pesticides acetamiprid, lambda-cyhalothrin, and cyfluthrin were harmful to rove beetle adults, whereas Beauveria bassiana (Balsamo) Vuillemin, azadirachtin, and organic oils (cinnamon oils, rosemary oil, thyme oil, and clove oil) were nontoxic to A. coriaria adults. Similarly, the plant growth regulators acymidol, paclobutrazol, and uniconazole were not harmful to rove beetle adults. In addition, B. bassiana, azadirachtin, kinoprene, organic oils, and the plant growth regulators did not negatively affect A. coriaria development. However, B. bassiana did negatively affect adult prey consumption. This study demonstrated that A. coriaria may not be used when applying the pesticides, acetamiprid, lambda-cyhalothrin, and cyfluthrin, whereas organic oils, B. bassiana, azadirachtin, and the plant growth regulators evaluated may be used in conjunction with A. coriaria adults. As such, these compounds may be used in combination with A. coriaria in greenhouse production systems
Effect Of Orius insidiosus (Hemiptera: Anthocoridae) And Spinosad (Conserve®) On Western Flower Thrips, Frankliniella occidentalis (Thysanoptera: Thripidae), Populations In Transvaal Daisy Flowers
Western flower thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is a major insect pest of greenhouse-grown horticultural crops. Greenhouse producers typically apply insecticides to suppress WFT populations. However, continual reliance on insecticides can lead to the development of resistant in WFT populations. The insidious flower bug, Orius insidiosus (Say) (Hemiptera: Anthocoridae), is a commercially available predatory bug of WFT that offers an alternative to using insecticides for WFT suppression. Therefore, we investigated the efficacy of one or two O. insidiosus adults compared to spray applications of the standard insecticide, spinosad (Conserve®) in suppressing WFT adult populations in transvaal daisy (Gerbera jamesonii), cut-flowers under greenhouse conditions. Percent adult WFT mortality was significantly lower when one or two O. insidiosus adults were released into the flowers (mean range: 32 to 34%; n=747), compared to the untreated and water control (8 to 9%; n=431). The highest percent mortality of WFT adults was associated with the spinosad (Conserve®) treatment (100%; n= 203)
THE ROLE OF MICROTUBULE-ASSOCIATED PROTEIN TAU IN NEURONAL EXCITABILITY AND EPILEPTOGENESIS
Tauopathies, including Alzheimer’s disease (AD), are devastating diseases with an immense burden on society which is predicted to increase in coming decades. In addition to progressive loss of memory and cognitive function, patients with tauopathies have a 6-10 fold increase in lifetime risk for seizures, and many are diagnosed with epilepsy. The presence of epileptiform activity on electroencephalogram (EEG) recordings from patients with AD predicts faster cognitive decline compared to patients without abnormal EEG readings. Electrophysiological measurements in murine models of AD have identified neuronal hyperexcitability. Furthermore, reducing tau phosphorylation or expression confers seizure resistance in animal epilepsy models. Although evidence suggests the presence of common mechanisms contributing to both tauopathy and epilepsy, more work is needed to understand how this interaction works and whether tau can be effectively targeted to improve patients’ lives. This study investigated the relationship between tauopathy using transgenic mice that expressed no tau protein (tau-/-) or expressed non-mutant, human tau protein without expressing murine tau (htau). The htau mice develop progressive tauopathy with age. Non-transgenic C57BL/6J mice were used as controls. Whole-cell patch-clamp electrophysiology was used to define tau’s role in neuronal excitability in vivo in dentate gyrus granule cells. Both transgenic mouse strains exhibited a lower frequency of evoked action potentials and reduced likelihood of neurotransmitter release from perforant pathway inputs as measured by the paired pulse ratio compared to control at 1.5 months of age, but these differences were lost with age. The similarities between the tau-/- and htau mice suggest that hyperexcitability is related to the amount of normally functioning tau rather than the presence of pathological tau, and that the presence of normal murine tau may influence the results of other studies involving models of tauopathy. Furthermore, tau’s role in epileptogenesis was studied using intrahippocampal injection of kainate (i.ie., IHK) to induce status epilepticus, a model that induces temporal lobe epileptogenesis, in tau-/-, htau, and C57BL/6J mice. The process of epileptogenesis appeared to be modified compared to control in both transgenic strains, but did not appear to be prevented. Compared to either tau-/- or C57BL/6J mice, htau mice experienced significantly greater mortality after IHK. Modifications in tau expression, wither deletion or humanization, partially abrogated synaptic excitability that developed following IHK.
In conclusion, this study showed that neuronal excitability is affected similarly by either deletion or humanization of tau, with the notable exception of survival after IHK. This study provides clearer understanding of tau’s role in acquired epilepsy and suggests novel therapeutics targeting tau may be effective for the treatment of epilepsy
Effects of Pesticides and Adjuvants on the Honey Bee, <em>Apis mellifera</em>: An Updated Bibliographic Review
The European or western honey bee, Apis mellifera, pollinates approximately 75% of crop species in agricultural and horticultural production systems worldwide at a value of 200 billion per year. While foraging for pollen and nectar in flowering plants, honey bees may be exposed to insecticides; however, they may also be exposed to a multitude of other pesticides and compounds including: fungicides, insect growth regulators, herbicides, and adjuvants. Previous and recent studies show that these pesticides and compounds are directly or indirectly harmful to honey bees, which could negatively impact pollination and colony health. Fungicides can directly and indirectly affect honey bees, and enhance the toxicity (synergize) of certain insecticides, thus increasing their toxic effects to honey bees. Insect growth regulators negatively affect larvae, which impacts brood production in honey bee colonies. Herbicides can indirectly affect honey bee populations by reducing the availability of flowering plants, which decreases pollen and nectar sources during foraging, and consequently reduces colony survival during the winter. Adjuvants, especially surfactants, are a component of pesticide formulations, and are indirectly harmful to honey bees. This book chapter provides a detailed discussion of the effects of fungicides, insect growth regulators, herbicides, and adjuvants on honey bees
Space probe/satellite ejection apparatus for spacecraft
An ejection apparatus for spinning and propelling objects for ejection from a spacecraft at a desired velocity and rotational speed is discussed. The apparatus includes a launch cradle on which the space object to be ejected rests. The cradle is rotatably supported by a central hub secured to the upper end of the pneumatic cylinder piston shaft. Release mechanisms consisting of a retractable pin and locking lug is utilized to hold the cradle and object to be ejected. The release mechanism has a fixed barrier member which holds the retractable pin in engagement with the locking lug until release by upward movement of the launch cradle beyond the barrier height
Efficacy of binary pesticide mixtures against western flower thrips
Citation: Cloyd, Raymond A., and Amy L. Raudenbush. 2014. “Efficacy of Binary Pesticide Mixtures Against Western Flower Thrips.” HortTechnology 24 (4): 449–56. https://doi.org/10.21273/HORTTECH.24.4.449.This study was designed to determine the efficacy of binary pesticide mixtures against one of the most important insect pests of greenhouse-grown horticultural crops, western flower thrips (Frankliniella occidentalis). Two separate experiments were conducted under greenhouse conditions to simulate a greenhouse production cycle using yellow transvaal daisy (Gerbera jamesonii) cut flowers, which were artificially infested with a known number of western flower thrips. The pesticides used in the two experiments were spinosad, pymetrozine, abamectin, pyridalyl, fluvalinate, chlorfenapyr, bifenazate, azadirachtin, petroleum oil, tolfenpyrad, fenhexamid, azoxystrobin, and spirotetramat. Pesticide mixtures were evaluated at the recommended labeled rates (Expt. 1) and assessments were made to determine if adding didecyl dimethyl ammonium chloride enhanced the efficacy of the pesticide mixtures (Expt. 2). Results from Expt. 1 indicated that many of the binary pesticide mixtures provided ≥80% mortality of western flower thrips although this was a baseline population without previous exposure to pesticides. In
Expt. 2, the addition of didecyl dimethyl ammonium chloride failed to increase the
efficacy of most of the designated pesticide mixtures compared with the pesticides applied separately. Furthermore, none of the binary pesticide mixtures were phytotoxic to the transvaal daisy flowers. Although there are issues associated with using pesticide mixtures such as the potential for resistance developing to different pesticides in mixtures, greenhouse producers combine pesticides together to reduce labor costs and expand the spectrum of activity against insect and mite (Tetranychidae) pests. Therefore, the relevance of this information is that greenhouse producers now understand which pesticide mixtures may be used and those that should be avoided when suppressing populations of western flower thrips thus minimizing feeding damage to greenhouse-grown horticultural crops
Manganese-Enhanced Magnetic Resonance Imaging: Overview and Central Nervous System Applications With a Focus on Neurodegeneration
Manganese-enhanced magnetic resonance imaging (MEMRI) rose to prominence in the 1990s as a sensitive approach to high contrast imaging. Following the discovery of manganese conductance through calcium-permeable channels, MEMRI applications expanded to include functional imaging in the central nervous system (CNS) and other body systems. MEMRI has since been employed in the investigation of physiology in many animal models and in humans. Here, we review historical perspectives that follow the evolution of applied MRI research into MEMRI with particular focus on its potential toxicity. Furthermore, we discuss the more current in vivo investigative uses of MEMRI in CNS investigations and the brief but decorated clinical usage of chelated manganese compound mangafodipir in humans
Integrated pest management in greenhouses and herbaceous nurseries (2009)
"Revised 10/09/2M.""Integrated pest management.
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