General

Chemical suppression of arthropod herbivores is the most common approach to plant protection. Insecticides, however, can cause unintended, adverse consequences for non-target organisms. Previous studies focused on the effects of pesticides on target and non-target pests, predatory arthropods, and concomitant ecological disruptions. Little research, however, has focused on the direct effects of insecticides on plants. Here we demonstrate that applications of neonicotinoid insecticides, one of the most important insecticide classes worldwide, suppress expression of important plant defense genes, alter levels of phytohormones involved in plant defense, and decrease plant resistance to unsusceptible herbivores, spider mites Tetranychus urticae (Acari: Tetranychidae), in multiple, distantly related crop plants. Using cotton (Gossypium hirsutum), corn (Zea mays) and tomato (Solanum lycopersicum) plants, we show that transcription of phenylalanine amonia lyase, coenzyme A ligase, trypsin protease inhibitor and chitinase are suppressed and concentrations of the phytohormone OPDA and salicylic acid were altered by neonicotinoid insecticides. Consequently, the population growth of spider mites increased from 30% to over 100% on neonicotinoid-treated plants in the greenhouse and by nearly 200% in the field experiment.

In Frankreich war die Aussaat von Genmais bislang nicht erlaubt. Allerdings hat das oberste Verwaltungsgericht dieses Anbauverbot gekippt. Nun sucht die Regierung nach juristischen Mitteln, um die Maissorte MON810 weiterhin von französischen Äckern fernzuhalten. "Diese Entscheidung schockiert uns zutiefst", sagt Olivier Belval. Er ist der Präsident der Nationalen Imker-Union in Frankreich. Zum wiederholten Mal bekam der US-Konzern Monsanto recht, diesmal vor dem obersten Verwaltungsgericht, dem französischen Staatsrat. So wankt das Verbot für den Anbau des genmanipulierten Mais MON810 erneut, das zunächst unter der konservativen Regierung 2007 und 2008 verhängt und das 2012 erneuert worden war.

Field and tunnel cage studies were undertaken to determine the extent to which honey bees foraging on citrus blossoms were exposed to imidacloprid and its metabolites when citrus trees were treated with soil applications of the insecticide. Imidacloprid, imidacloprid olefin and 5-hydroxy imidacloprid were detected in nectar and pollen sampled from the flowers of citrus trees treated with imidacloprid up to 232 days prior to bloom. In tunnel studies, where foraging was restricted exclusively to citrus, imidacloprid residues in nectar extracted from flowers and from bee crops were similar (<10 ng mL−1); the residue levels were about threefold higher in nectar sampled from comb. Concentrations of imidacloprid in nectar were higher in trees treated with higher application rates.

Upon request from the European Commission, the European Food Safety Authority prepared a scientific report that would aid the future establishment of protocols for chronic toxicity and/or carcinogenicity studies in rodents with whole food/feed. This scientific report provides a commentary on OECD TG 453 with considerations on its applicability to support the safety assessment of long term consumption of a given food with respect to its chronic toxicity or carcinogenicity potential. The decision to conduct chronic toxicity and/or carcinogenicity studies with whole food/feed should be taken on a case-by case basis. It should be based on the evaluation of all the available information on the whole food/feed resulting from compositional analyses and any other available nutritional and toxicological studies. The conduct of the study and its reporting should be in line with good laboratory practice standards. Preparation of appropriate test diets is a key element of the experiment with respect to characterisation of the starting material and of the diet, level of inclusion of whole food/feed, nutritional balance, processing and storage. Statistical considerations are discussed to assist in estimating the number of animals necessary to obtain a suitable sample size capable of detecting biologically relevant effects with a pre-specified power and significance level. A comprehensive set of endpoints as set out in the OECD TG 453 should be measured during and at the end of the study, as appropriate. The collection of data and reporting should ensure a thorough biological and statistical evaluation. Recommendations on the relevant issues to be considered when designing chronic toxicity and/or carcinogenicity studies in rodents with whole food/feed are provided throughout the report and summarised in the conclusions.

Glyphosate, the active ingredient in Roundup®, is the most popular herbicide used worldwide. The industry asserts it is minimally toxic to humans, but here we argue otherwise. Residues are found in the main foods of the Western diet, comprised primarily of sugar, corn, soy and wheat. Glyphosate's inhibition of cytochrome P450 (CYP) enzymes is an overlooked component of its toxicity to mammals. CYP enzymes play crucial roles in biology, one of which is to detoxify xenobiotics. Here, we show how interference with CYP enzymes acts synergistically with disruption of the biosynthesis of aromatic amino acids by gut bacteria, as well as impairment in serum sulfate transport. We explain the documented effects of glyphosate and its ability to induce disease, and we show that glyphosate is the “textbook example” of exogenous semiotic entropy: the disruption of homeostasis by environmental toxins.

Wer kennt sie noch? Blühende Ackerraine mit Klatschmohn, Kornblume, Acker-Rittersporn und Sommer-Adonisröschen. Waren sie in den sechziger Jahren noch ein häufiger Anblick, gilt heute fast jede zweite Ackerwildkrautart in Niedersachsen als akut gefährdet. „Sogar die Kornblume ist auf unseren Äckern in Südniedersachsen kaum noch zu finden“, sagt Reinhard Urner, der stellvertretender Vorsitzender des Landschaftspflege­verbandes ist. Die fast vergessenen Ackerwildkräuter böten eine beeindruckende Vielfalt an Arten, Formen und Farben in der Kulturlandschaft. Diese Vielfalt solle auch künftigen Generationen noch erhalten bleiben, meint Urner: „Der wachsende wirtschaftliche Druck in der Landwirtschaft lässt keinen Platz mehr für die Beikräuter. Durch ausgefeilte Unkraut­bekämpfung sind die früher von blühenden Wildkräutern durchsetzten Ackerflächen heute nahezu frei von Begleitflora und -fauna.“ Der Rückgang der Ackerwildkräuter ist in ganz Deutschland festzustellen.

Das zeigt eine Studie an Hummeln im US-Staat Colorado. Blieb dort nur eine einzige der insgesamt elf Hummelarten einer Blumenwiese fern, so bildeten manche Pflanzen ein Drittel weniger Samen, wie die Forscher in den "Proceedings" der US-Nationalen Akademie der Wissenschaften ("PNAS") schreiben. Der Grund: Viele verbleibende Hummeln wurden ihren bisherigen Blüten untreu.

There is now compelling evidence of a reduction of pollinator richness and density at a global scale. In this opinion article, we argue that such pollinator decline intensifies pollen limitation and reduces plant reproductive success, threatening natural populations of extinction. We use genetic architecture and selection experiments on floral traits and evaluate the potential for plant reproductive strategies to adapt rapidly to new pollination environments. We propose that plant reproductive strategies could adapt to the current pollinator decline by decreasing or increasing their reliance to pollinators, for example, increasing autonomous selfing or reinforcing interactions with pollinators. We further discuss if and how adaptation of plant reproductive strategies can buffer the demographic consequences of pollinator decline, and possibly rescue plant populations from extinction.

Rozenkwekerij de Bierkreek heeft 340.000 euro subsidie van het Ministerie van Economische Zaken gekregen om een methode op de markt te zetten om containerteelt zonder insecticiden mogelijk te maken. De Bierkreek gaat de komende vier jaar samen met HAS Hogeschool en HAS kennistransfer aan het project werken. Om containerteelt vrij van insecticiden te krijgen zijn voornamelijk aanpassingen van containervelden nodig. Door het aantrekken van natuurlijke vijanden als zweefvliegen, sluipwespen, lieveheersbeestjes en gaasvliegen zijn minder bestrijdingsmiddelen nodig. Hierdoor zou de plant beter beschermd zijn tegen schade door luizen, trips, spint en andere insecten. HAS-studenten onderzoeken hoe de inrichting van een containerveld moet worden aangepast. De Bierkreek is op zoek naar tuincentra, handelaren en kwekers die willen meewerken aan dit project. Het hoeven geen biologisch gecertificeerde bedrijven te zijn.

First genetically engineered plants were created 30 years ago. Commercial growing in the USA began almost 20 years ago. Initially, although US farmers had a number of advantages from cultivating herbicide-resistant crops (savings in working time, spraying lesser amounts of herbicide to kill weeds) this is now mostly reversed. The weeds have adapted to the cultivation of the genetically engineered plants so that farmers are experiencing a substantial increase in both working hours and the amounts of herbicide they require. Even the pest insects targeted by the cultivation of insecticide-producing plants have partially adapted. Secondary pests have now spread throughout maize cultivations and we have a scenario where plants have been genetically engineered to produce up to six different toxins. Agricultural technologies are drawing farmers into a production systemisation that will force agriculture towards more industrialisation and massively increase costs for seeds, without there being a substantial increase in yields or significant savings in the amounts of spray required.