Two important Czech events in August

Public disinformation and superstitions are most serious burdens of biotechnology developments and prevent its use for the benefit of society and nature. Thus any event providing facts and experiences to public makes it easier to put the effort of scientists in practice. Two such events occurred in August in the Czech Republic.

(1) The International Conference on Invertebrate Reproduction and Development in the Age of Genetic Modifications was organized on August 16 to 20 in Prague ( see http://icird.bc.cas.cz/ )

(2) New Technologies in Agriculture - their Use in Food Production. In the frame of an agriculture exhibition Země Živitelka in České Budějovice.

Both events brought important information concerning important impacts of GMO - environment and food. Using the summary assembled by the Biology Centre of AS CR we are providing brief reports on both.

International Conference on Invertebrate Reproduction and Development in the Age of Genetic Modifications

Organized by the Biology Centre of the Academy of Sciences of the Czech Republic,

České Budějovice,
and
the Crop Research Institute, Prague,
with support of the 7FP EU project MOBITAG

Most interest for biotechnology represented the section

Session 6: Impact of genetically modified crops on arthropod development and reproduction. It included following presentations:

Role of biotechnology in crop protection: towards sustainability by Gatehouse Angharad, Newcastle University, UK.

The author provided an overview of the current status of insect-resistant transgenic crops and their contribution to global food security. The potential for pest populations to evolve resistance was discussed and the lack of toxicity towards homopteran pests stressed. Te author highlighted the need for alternative strategies to Bt. This cals for the search and development of novel molecules for expression. Since the role of such crops within an integrated pest management programme, and in particular their impact on non-target organisms, is key to their successful adoption, their effects on natural enemies (parasitoids and predators) must be studied and compared with possible alternative measurers.

For more information, please, contact A.M.R.Gatehouse@newcastle.ac.uk

Mode of action of Bacillus thuringiensis toxins and insect resistance by Ferré Juan, University of Valencia, It.

Bacillus thuringiensis (Bt) produces a variety of insecticidal compounds which constitute the active ingredient of many bioinsecticides, being the Cry proteins and the Vip proteins the ones with the highest potential for biotechnological applications. The most successful application of Bt is the development of insect-resistant plants (over 50 million hectares planted with Bt crops in 2009). Bt toxins are toxic by ingestion; both Cry proteins and Vip proteins need to be activated in the insect midgut prior to binding to membrane receptors in the gut epithelium. Although the events that take place after binding are not completely understood, pore formation seems to be the most important event leading to cell death. The main threat of the use of Bt insecticidal proteins is the evolution of resistance in insect populations. Laboratory selection has produced a long list of Bt resistant colonies. However, very few insect species have evolved resistance to Bt toxins outside the laboratory, either to spray formulations or to Bt-plants. To preserve the long term use of the Bt-crop technology, it is important to understand the mechanisms by which insects become resistant against Bt toxins. The study of the mechanisms of resistance in many resistant strains has shown that the most common mechanism conferring high levels of narrow-spectrum resistance is an alteration in the binding site of Bt toxins. This mechanism has also been proposed to be the most likely one to be selected under field conditions.

For more information, please, contact juan.ferre@uv.es

Biotechnological solutions for protecting wheat against insect pests, by Gatehouse J. A., Durham University, UK.

Current commercial wheat varieties, and diploid primitive wheat lines, have been screened for resistance to two significant insect pests of wheat in UK agriculture, cereal aphid, Sitobion avenae, and wheat bulb fly, Delia coarctata. None of the wheats tested were resistant to attack by either pest. To show that wheat contains proteins with potential insecticidal activity, selected defensive proteins were produced as recombinant proteins and assayed. Two endogenous proteinase inhibitors accumulated in wheat tissues, wheat cystatin (WCPI) and the wheat subtilisin-chymotrypsin inhibitor (WSCI) had insecticidal activity towards cereal aphids. WSCI was also active against wheat bulb fly. A protein whose expression was upregulated in Hessian fly-resistant wheat, designated Hfr3, was strongly toxic to cereal aphids in a dose-dependent manner, and had activity against bulb fly. These results show that endogenous genes in wheat can confer resistance. Synthetic recombinant fusion proteins containing a plant lectin domain fused to an insecticidal protein or peptide have a novel oral toxicity to insects as a result of the lectin domain acting as a "carrier" to transport the toxin across the gut to its site of action. Fusion proteins containing toxins from spiders and scorpions have been shown to be effective oral insectides towards both cereal aphids and bulb fly larvae; these pests cannot be targetted by existing commercial Bt toxins. These results show that fusion proteins have the potential to protect wheat against insect pests, but will require to be used as part of a transgenic strategy to give protection in the field.

For more information, please, contact J.A.Gatehouse@durham.ac.uk

Novel strategies for insect-resistant transgenic crops: use of molecules from biocontrol agents by Pennacchio Francesco, University of Napoli "Federico II", It.

Parasitoid insects are specialized wasps which attack and use as a host a number of insect species, and have developed an impressive range of host colonization strategies, all resulting in severe pathological syndromes in parasitized hosts. The molecular bases of these host pathologies are currently being investigated in quite a few groups, and the isolation and functional characterization of the molecules/genes involved in the host regulation may offer interesting opportunities for discovering new bioinsecticides and for developing novel strategies of pest control. A brief overview of the basic knowledge in a few host-parasitoid model systems and of the current exploitation strategies of this information for developing new insect pest control biotechnologies was presented.

For more information, please, contact f.pennacchio@unina.it .

The impacts of Galanthus nivalis agglutinin (GNA) and other novel transgene proteins on parasitic wasps by Bell Howard A., Food and Environment Research Agency, Sand Hutton, York, UK

The anti-insect properties of snowdrop lectin (GNA) has led to it being widely evaluated as a potential candidate for expression in genetically modified crops for the purpose of enhancing resistance to arthropod pests. The work to date has demonstrated that, for certain insect pest species, consumption of the lectin can result in marked deleterious effects on survival, growth, food intake and fecundity, either when GNA is expressed in transgenic plants or delivered via artificial diet. The ongoing interest in exploiting GNA for crop protection has, in turn, led to widespread research into the possibility that this lectin could deleteriously affect non-target insects, particularly beneficial biological control agents such as parasitoids. To date, a range of impacts have been reported, ranging from the moderately beneficial to the significantly detrimental, depending on the species of parasitoid under investigation, the life stage evaluated and the routes of exposure. The current paper reviews much of the non-target research that has been conducted up to now with respect to GNA and compares and contrasts these findings with the impacts of other potential transgene proteins, such as protease inhibitors and fusion proteins. The need for more insightful experimental procedures will be   phasised, as will the need to place results in the context of modern agricultural practices as opposed to drawing over-simplistic conclusions based solely on comparisons with untreated controls.

For more information, please, contact howard.bell@fera.gsi.gov.uk

Impact of insect‐resistant transgenic crops on insect predators by Ferry Natalie, University of Salford, Salford Crescent, Salford, Greater Manchester. UK.

Many consumer and environmental lobby groups believe that GM crops will bring very little benefit to growers and to the general public and that they will have a deleterious impact on the environment. This presentation uses the example of the impact of insect resistant GM crops on agriculturally important predatory insects to ask the following questions: Has a scientifically rigorous risk assessment procedure been settled upon? Is there now a history of safe use? What value is there in gathering more data? What questions remain to be answered?

For more information, please, contact n.ferry@salford.ac.uk

Impacts of stacked Bt maize on non‐target Lepidoptera in agrarian systems by Rauschen Stefan, RWTH Aachen University, Aachen, Germany.

The cultivation of Bt maize expressing lepidopteran-specific Cry proteins poses a potential risk for non-target butterflies. Therefore it is necessary (i) to assess the hazard posed by Cry proteins in pollen; (ii) to estimate the deposition of pollen on the host plants of caterpillars in the field; (iii) to obtain data on the occurrence of larvae in relation to maize fields during anthesis. We chose the Small Tortoiseshell (Aglais urticae) and the Peacock (Inachis io), two species common in European agrarian landscapes, as test organisms. Their larvae feed on Stinging nettle (Urtica dioica). The Bt maize cultivar studied was DKC 5143-Bt (event MON 89034 x MON 88017), expressing Cry1A.105 (8.6 μg/g pollen FW) and Cry2Ab2 (0.33 μg/g pollen FW) directed against Lepidopteran pests. The toxicity of pollen was tested in singledose feeding studies with different amounts of pollen to determine effect thresholds. Caterpillars and their host plants were mapped in two agrarian landscapes at the time of anthesis. Pollen deposition was measured at an experimental field site. A dose of up to 300 pollen/cm2 did not reveal significant differences in mortality rates of L3 larvae of A. urticae. The average deposition of pollen on nettle leaves directly at the maize field margin was 29±41 grains/cm2. In a distance of five meters pollen density was 3±4 grains/cm2, decreasing further with increasing distance. Over 72% of butterfly nests were found in distances of at leas

For more information, please, contact rauschen@bio3.rwth-aachen.de

Impact of Bt maize on target and non-target arthropods in the field by Ortego Félix, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain

Genetically modified maize plants expressing the Cry1Ab toxin from Bacillus thuringiensis (Bt maize) have been cultivated in Spain at a commercial scale since 1998. A post-market monitoring plan, aimed to assess the impact of Bt maize on target and non-target arthropods in the field, has been operating for the last twelve years. Bt maize provides an effective control of two key lepidopteran pests, the Mediterranean corn borer (MCB), Sesamia nonagrioides (Lefèbvre) and the European corn borer (ECB), Ostrinia nubilalis (Hübner). Monitoring for field resistance in target insects is being assessed by changes in susceptibility from baseline levels. Annual monitoring has been conducted on Bt maize fields from representative regions during the period 1998-2009. So far, no changes in the susceptibility to the Cry1Ab toxin have been found, which is consistent with the fact that there have been no  control failures reported in transgenic Bt maize fields. Post-market monitoring to determine potential effects of Bt maize on non-target arthropods has focused on field trials conducted at two different agronomic areas in northeast (Lleida) and central (Madrid) Spain over 5 years.  In general, the abundance and diversity varied from year to year and between locations, but no detrimental effects of Bt maize on predators and non-target herbivores were found. The results obtained from the Spanish farm scale studies agree with data available from other field trials conducted in Europe, suggesting that Bt maize could be compatible with the natural enemies that are common in maize fields in Europe.

For more information, please, contact ortego@cib.csic.es

All presentations brought facts indicating that transgenic crops are more environment friendly than "classical" or "traditional" measures - i.e. spraying by insecticides.

Author: Prof. Jaroslav Drobník