Neonicotinoid insecticides severely affect honey bee queens

Queen health is crucial to colony survival of social bees. Recently, queen failure has been proposed to be a major driver of managed honey bee colony losses, yet few data exist concerning effects of environmental stressors on queens. Here we demonstrate for the first time that exposure to field realistic concentrations of neonicotinoid pesticides during development can severely affect queens of western honey bees (Apis mellifera). In pesticide-exposed queens, reproductive anatomy (ovaries) and physiology (spermathecal-stored sperm quality and quantity), rather than flight behaviour, were compromised and likely corresponded to reduced queen success (alive and producing worker offspring). This study highlights the detriments of neonicotinoids to queens of environmentally and economically important social bees, and further strengthens the need for stringent risk assessments to safeguard biodiversity and ecosystem services that are vulnerable to these substances.

A DERMATOLOGICAL EVALUATION OF SYNTHETIC PYRETHROID INSECTICIDES (PARESTHESIA, FENVALERATE, PERMETHRIN)

In this investigation, differences in parasthesia were detected by human participants between synthetic pyrethroids with a cyano group in the (S)-configuration of the 3-phenoxybenzyl alcohol of their molecular structure (fenvalerate) and those that do not (permethrin). A strong relationship was noted between insecticidal potency and degree of induced cutaneous sensation for the alpha-cyano and non-cyano pyrethroids, with a prominent difference between the two. A linear correlation between concentration and degree of induced dysesthesia was observed for both pyrethroids. Regressing the cutaneous sensation on the common logarithm of concentration resulted in a regression equation of Y = 84.0 + 31.0X(,1) for fenvalerate and Y = 27.5 + 15.8X(,1) for permethrin. An evaluation for dermal cytotoxicity in albino rabbits yielded a slight increase in cutaneous perfusion as indicated both visually and by laser Doppler velocimetry. However, no significant difference was detected in edema or thermal variation. Histopathological alterations were minimal after repeated daily applications with the majority of changes involving acanthosis. A highly efficacious therapeutic agent for pyrethroid exposure was noted to be dl-alpha tocopherol acetate. An impressive degree of inhibition of parasthesia resulted from the topical application of vitamin E acetate, with a therapeutic index of almost 100%. ^

Illustrated Botanical Books, Fifteenth, Sixteenth, Seventeenth Centuries

No attempt has been made for a comprehensive coverage of the many outstanding illustrated botanical books for this three hundred year period. Rather the aim has been for a combination of interesting illustrators and famous botanists. Like the exhibit on fine bird books, these books on display have been taken from the Rare Books division of Special Collections.

Evaluation of Bt and Non-Bt Corn with and without Soil Insecticides for Control of Corn Rootworm

The purpose of this study was to evaluate the effectiveness of Bt corn and soil insecticides, either alone or in combination, for the control of corn rootworm. Evaluation of Bt hybrids included SmartStax, SmartStax with refuge in a bag, and Herculex XTRA. Soil insecticides evaluated were SmartChoice-SB, Counter-SB, Aztec, and Force.

Evaluation of Foliar Fungicides and Insecticides on Soybean

Use of foliar fungicides and insecticides are an effective strategy for managing foliar diseases on soybean. There are many different fungicides and insecticides available for use currently in Iowa. Iowa State University personnel assessed the success of fungicides and insecticides across Iowa. This study was conducted at six locations: Sutherland (NW), Kanawha (NC), Nashua (NE), Ames (central), Crawfordsville (SE), and Lewis (SW) research farms (Figure 1).

Evaluation of Foliar Fungicides and Insecticides on Soybeans

Use of foliar fungicides and insecticides are an effective strategy for managing foliar diseases of soybean. There are many different fungicides and insecticides available for use currently in Iowa. Iowa State University personnel assessed the success of fungicides and insecticides across Iowa. This study was conducted at six locations: Sutherland (NW), Kanawha (NC), Nashua (NE), Ames (central), Crawfordsville (SE), and Lewis (SW) research farms (Figure 1).

Evaluation of Bt and Non-Bt Corn with and without Soil Insecticides for Control of Corn Rootworm

The purpose of this study was to evaluate the effectiveness of Bt corn and soil insecticides, either alone or in combination, for the control of corn rootworm. Evaluation of Bt hybrids included SmartStax, SmartStax with a blended refuge (refuge in the bag), and Herculex XTRA. Soil insecticides evaluated were SmartChoice-SB, Counter-SB, Aztec, and Force.

Evaluation of Foliar Fungicides and Insecticides on Soybeans

Use of foliar fungicides and insecticides are an effective strategy for managing foliar diseases of soybean. There are many different fungicides and insecticides available for use currently in Iowa. Iowa State University personnel assessed the success of fungicides and insecticides across Iowa. This study was conducted at six locations: Sutherland (NW), Kanawha (NC), Nashua (NE), Ames (central), Crawfordsville (SE), and Lewis (SW) research farms (Figure 1).

Evaluation of Foliar Fungicides and Insecticides on Soybeans

Use of foliar fungicides and insecticides are an effective strategy for managing foliar diseases of soybean. There are many different fungicides and insecticides available for use currently in Iowa. Iowa State University personnel assessed the success of fungicides and insecticides across Iowa. This study was conducted at six locations: Sutherland (NW), Kanawha (NC), Nashua (NE), Ames (central), Crawfordsville (SE), and Lewis (SW) research farms (Figure 1).

Pollen assemblages of modern soil samples from the Old Botanical Garden of the University of Göttingen

The importance of pollen analytical data for the reconstruction of the natural conditions and their changes caused by human impact in prehistorical and historical times is beyond all doubt. Pollen analysis can, however, be hampered by poor pollen preservation and low pollen concentrations. As an example pollen assemblages from excavation areas near Pompeii (see doi:10.1594/PANGAEA.777531) and from the Old Botanical Garden of the University of Göttingen are discussed. A pollen diagram (see doi:10.1594/PANGAEA.820590) from the site Höllerer See in Austria (N of the city of Salzburg) demonstrates the intensive agricultural influence on the vegetation of the area during Roman and Medieval times. Human influence was much weaker during the Iron and the Bronze ages. There is no indication of human impact on the vegetation during the Migration period.

Selectivity of diacylhydrazine insecticides to the predatory bug Orius laevigatus: In vivo and modeling/docking experiments

BACKGROUND: Knowledge of pesticide selectivity to natural enemies is necessary for a successful implementation of biological and chemical control methods in integrated pest management (IPM) programs. Diacylhydrazine (DAH)-based ecdysone agonists also known as molting-accelerating compounds (MACs) are considered a selective group of insecticides, and their compatibility with predatory Heteroptera, which are used as biological control agents, is known. However, their molecular mode of action has not been explored in beneficial insects such as Orius laevigatus (Fieber) (Hemiptera: Anthocoridae). RESULTS: In this project in vivo toxicity assays demonstrated that the DAH-based RH-5849, tebufenozide and methoxyfenozide have no toxic effect against O. laevigatus. The ligand-binding domain (LBD) of the ecdysone receptor (EcR) of O. laevigatus was sequenced and a homology protein model was constructed which confirmed a cavity structure with 12 ?-helixes, harboring the natural insect molting hormone 20-hydroxyecdysone. However, docking studies showed that a steric clash occurred for the DAH-based insecticides due to a restricted extent of the ligand-binding cavity of the EcR of O. laevigatus. CONCLUSIONS: The insect toxicity assays demonstrated that MACs are selective for O. laevigatus. The modeling/docking experiments are indications that these pesticides do not bind with the LBD-EcR of O. laevigatus and support that they show no biological effects in the predatory bug. These data help in explaining the compatible use of MACs together with predatory bugs in IPM programs. Keywords: Orius laevigatus, selectivity, diacylhydrazine insecticides, ecdysone receptor, homology modelling, docking studies.

Insect growth regulators as potential insecticides to control olive fruit fly (Bactrocera oleae Rossi): insect toxicity bioassays and molecular docking approach

Olive fruit fly, Bactrocera oleae (Rossi), is a key pest in olive orchards, causing serious economic damage. To date, the pest has already developed resistance to the insecticides commonly applied to control it. Thus, in searching for new products for an accurate resistance management programme, targeting the ecdysone receptor (EcR)might provide alternative compounds for use in such programmes. RESULTS: Residual contact and oral exposure in the laboratory of B. oleae adults to the dibenzoylhydrazine-based compounds methoxyfenozide, tebufenozide and RH-5849 showed different results. Methoxyfenozide and tebufenozide did not provoke anynegative effectsontheadults,but RH-5849 killed98-100%of the treated insects15 days after treatment. Theligand-binding domain (LBD) of the EcR of B. oleae (BoEcR-LBD) was sequenced, and a homology protein model was constructed. Owing to a restricted extent of the ligand-binding cavity of the BoEcR-LBD, docking experiments with the three tested insecticides showed a severe steric clash in the case of methoxyfenozide and tebufenozide, while this was not the case with RH-5849. CONCLUSION: IGR molecules similar to the RH-5849 molecule, and different from methoxyfenozide and tebufenozide, might have potential in controlling this pest.

Toxicity and sublethal effects of six insecticides to last instar larvae and adults of the biocontrol agents Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) and Adalia bipunctata (L.) (Coleoptera: Coccinellidae)

To further develop Integrated Pest Management (IPM) strategies against crop pests, it is important to evaluate the effects of insecticides on biological control agents. Therefore, we tested the toxicity and sublethal effects (fecundity and fertility) of flonicamid, flubendiamide, metaflumizone, spirotetramat, sulfoxaflor and deltamethrin on the natural enemies Chrysoperla carnea and Adalia bipunctata. The side effects of the active ingredients of the insecticides were evaluated with residual contact tests for the larvae and adults of these predators in the laboratory. Flonicamid, flubendiamide, metaflumizone and spirotetramat were innocuous to last instar larvae and adults of C. carnea and A. bipunctata. Sulfoxaflor was slightly toxic to adults of C. carnea and was highly toxic to the L4 larvae of A. bipunctata. For A. bipunctata, sulfoxaflor and deltamethrin were the most damaging compounds with a cumulative larval mortality of 100%. Deltamethrin was also the most toxic compound to larvae and adults of C. carnea. In accordance with the results obtained, the compounds flonicamid, flubendiamide, metaflumizone and spirotetramat might be incorporated into IPM programs in combination with these natural enemies for the control of particular greenhouse pests. Nevertheless, the use of sulfoxaflor and deltamethrin in IPM strategies should be taken into consideration when releasing either of these biological control agents, due to the toxic behavior observed under laboratory conditions. The need for developing sustainable approaches to combine the use of these insecticides and natural enemies within an IPM framework is discussed.