A new method to assess the acute toxicity toward honeybees of the abrasion particles generated from seeds coated with insecticides

Background:Large amounts of insecticide-containing dusts produced from abrasion of the seed dressing can be released into the atmosphere during sowing operations. Neonicotinoid pesticides, introduced in the 1990s for several crops, are the leading products for seed-coating treatments in many countries. Neonicotinoid containing dusts can be effectively intercepted by bees in flight over the sowing field, inducing lethal acute effects, so that restrictions in the use of the main neonicotinoids have been adopted in the European Union. This led to the consequent introduc-tion of replacement insecticides for seed-coating, i.e. methiocarb and thiacloprid, despite the lack of information on both the toxicity and the exposure scenarios for honeybees. Results:In this study, a laboratory apparatus was developed in order to quantify the toxicity of the dusts produced from the abrasion of the seed coating. This quantification is based on (i) an airstream transporting coating particles into an exposure chamber; (ii) exposure of bees to reproducible and measurable concentrations of insecticide, and (iii) direct measurement of the exposure dose on single bees. The method allowed us to perform in vivo experiments of honeybee exposure to provide toxicity data in more realistic exposure conditions. In fact, the formulation rather than the active principle alone can be tested, and the exposure is through dusts rather than a solution so that specific absorption behavior can be studied in representative environmental conditions. The method was used to quantify the acute toxicity (LD50) of dusts obtained from the abrasion of corn seeds coated with clothianidin, thiacloprid and methiocarb. Conclusions:Our results show that, surprisingly, the replacement insecticide methiocarb has a toxicity (LD50= 421\u2013693 ng/bee) in the same order of magnitude as clothianidin (LD50=113\u2013451 ng/bee) through this specific exposure route, while thiacloprid (LD50= 16.9\ub7103 ng/bee) has a significantly lower acute toxicity. Moreover, dusts containing methiocarb and clothianidin show a significant increase in toxicity when, after exposure, bees are kept under high humidity conditions. This suggests that the method here presented can be used to obtain complementary toxicity data in the risk assessment procedure for the authorization of new seed-coating insecticides or new formulations

Arbuscular mycorrhizal colonization in black poplar roots after defoliation by a non-native and a native insect

A major goal in ecology is to understand how interactions among organisms influence ecosystem services. This work compares the effects of two Lepidoptera defoliators, one non-native (Hyphantria cunea) and one native (Lymantria dispar) to Europe, on the colonization of black poplar (the Populus nigra clone "Jean Pourtet") roots by an arbuscular mycorrhizal (AM) symbiotic fungus (Funneliformis mosseae) in a pot experiment. The effects of defoliation have also been assessed on the expression of fungal and plant genes playing a role during symbiosis. Both control and defoliated poplars have shown a low level of mycorrhization. Additionally, neither the non-native nor the native insect seem to strongly affect the AM colonization, at least at the time of observation (eight days from the end of the defoliation). Concerning the gene expression analysis, our results suggest that defoliation does not influence neither the expression of genes coding for a fungal and a plant phosphate transporter nor that of a gene coding for a fungal ATPase, and that there were no differences between defoliation carried out by the non-native and the native insect. \ua9 SISEF

Setae from the pine processionary moth (Thaumetopoea pityocampa) contain several relevant allergens

BACKGROUND: Pine processionary larvae produce urticating hairs (setae) that serve for protection against predators. Setae induce cutaneous reactions in animals and humans. The presence of toxic or allergic mechanisms is a matter of debate. OBJECTIVES: To detect the presence of allergens in setae and to characterize them. MATERIALS AND METHODS: Setae extracts were characterized by gel staining and immunoblot, with sera from patients with immediate reactions and positive prick test reactions, as well as a rabbit antiserum raised against setae. Setae proteins were fractionated by high-performance liquid chromatography. The most relevant allergen was analysed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS), and its sequence was deduced from an expressed sequence tag bank. Results. Setae contained at least seven different allergens. The most intense detection corresponded to a protein of MW ~ 14,000 that was similar to thaumetopoein, a previously described protein with mast cell-degranulating properties. MALDI-MS-based de novo sequencing provided a partial amino acid sequence different from that of the previously described allergen Tha p 1, and it was named Tha p 2. This allergen was detected in 61% of patients, and it is therefore a new major caterpillar allergen. CONCLUSIONS: Penetration of the setae from the pine processionary caterpillar delivers their allergenic content in addition to causing mechanical or toxic injury.This work was supported by URTICLIM, a French project funded by the ‘Agence Nationale de la Recherche’ (ANR 07BDIV 013). Ana I. Rodriguez-Mahillo is a beneficiary of contract CA07/00046 from the Instituto de Salud Carlos III, Ministerio de Ciencia e Innovacion, Spain.S

Climate change and pine processionary moth role of the host plant

The thesis shows some results about the pine processionary moth to low temperature, host-plants, carbon dioxide end snow cover

Performances of an expanding insect under elevated CO2 and snow cover in the Alps.

Variations of phenology and distribution have been recently highlighted in numerous insect species and attributed to climate change, particularly the increase of temperature and atmospheric CO2. Both have been shown to have direct and indirect effects on insect species of various ecosystems, though the responses are often species-specific. The pine processionary moth, Thaumetopoea pityocampa (Lepidoptera, Notodontidae) is an important pest of conifers in the Mediterranean region, and has been recently shown to expand its altitudinal range in the Alps, including the mountain pine Pinus mugo as a novel host. We had the opportunity to transplant colonies of the pine processionary moth to a high elevation site well outside of the current range of the insect (Stillberg, Davos, Switzerland, 2180 m), where trees of the mountain pine have been grown for five years under ambient and elevated CO2 concentrations (ca. 570 ppm). The aim of the study was to evaluate the response of first instar larvae to extreme conditions of temperature and to an altered performance induced by the change of host metabolism under elevated CO2. Larval mortality and relative growth rate did not differ between host trees grown in ambient or elevated CO2. As extended snow cover may be an important mortality factor of larval colonies on the dwarf trees of mountain pine, we tested the survival of colonies transplanted at two extreme sites of Eastern Alps. The snow cover extended over more than one month proved to be an important mortality factor of larval colonies on mountain pine. We concluded that the first instar larvae of the pine processionary moth are not concerned by unusually low temperature and CO2 increase whereas they can be later strongly affected by snow accumulation. The decrease of snow cover observed in the last decades, however, may reduce such a risk

First record of Cyrtogenius strohmeyer in Europe, with a key to the European genera of the tribe Dryocoetini (coleoptera: Curculionidae, scolytinae)

The genus Cyrtogenius Strohmeyer, represented by the species C. luteus (Blandford, 1894), is reported for the first time in Europe. Many adults were collected for four consecutive years (2009-2012) in various localities of northern Italy in both multifunnel and cross-vane traps baited with multilure blends. A diagnosis of the species and a revised key to the European genera of tribe Dryocoetini Lindemann is also reported. An explanation is suggested for the increasing number of recent introductions of exotic scolytids into Europe. Copyright © 2012 Magnolia Press

FIGURE 3 in First record of Cyrtogenius Strohmeyer in Europe, with a key to the European genera of the tribe Dryocoetini (Coleoptera: Curculionidae, Scolytinae)

FIGURE 3. Ventro-lateral margin of the declivity of Cyrtogenius luteus slightly elevated and armed of small granules

Comparative Structure of the Urticating Apparatus in Processionary Moths

La partie est intégrée dans le Chapter 8: Medical and Veterinary Impact of the Urticating Processionary LarvaeInternational audienc