Research team deciphers adhesive mechanisms in pollination

Microscopic image of pollen adhering to part of plant.

(Kiel University) During transport from one flower to another by insects, pollen must repeatedly attach to and detach from different surfaces. To date, the underlying adhesive mechanisms have hardly been studied. “If pollen is transported by insects from flower to flower, it encounters three different types of surfaces to which it must attach itself and then detach again. We want to find out which adhesive mechanisms enable this.”

Pesticide widely used in US particularly harmful to bees, study finds

Image of honey bees.

(The Guardian) Agriculture in the United States has become 48 times more toxic to insects over the last 25 years, largely due to neonicotinoid pesticides, according to the study. “We have not learned our lessons… There’s this fundamental recklessness and foolishness to introducing [neonics] and continuing down this path,” says Kendra Klein, an author of the study and a senior scientist at not-for-profit Friends of the Earth. The study can be found here.

This tiny insect could be delivering toxic pesticides to honey bees and other beneficial bugs

Image of mealybugs on a leaf.

(Science) A common pesticide may be causing more collateral damage than thought. According to a new study, neonicotinoids can kill beneficial insects such as honey bees, hoverflies and parasitic wasps by contaminating honeydew, a sugar-rich liquid excreted by certain insects. This can devastate more insects across the food web than nectar contaminated with insecticides could, the research team says, because honeydew is more abundant, especially in agricultural fields.

New Xerces fact sheet takes a deeper look at fungicides and their effects on pollinators

Graphic showing how fungicides can impact the health of pollinators.

(Xerces Society) Research has shown that some fungicides kill bees on contact. Studies have shown that some fungicides increase the toxic effects of certain insecticides. Fungicide exposure has also been linked to higher levels of parasitic and viral infections in honey bee colonies, suggesting that some fungicides may impair a bee’s ability to fight disease. The Xerces Society’s new fact sheet, “Protecting Pollinators from Pesticides: Fungicide Impacts on Pollinators”, reviews the current literature on fungicides and pollinators to help piece together potential risks and how best to respond.

Adjuvants amplify the toxicity of pesticides on honey bees

Image of researcher among yellow flowers.

(EurekAlert/Society of Environmental Toxicology and Chemistry) When applied alone, adjuvants – chemicals commonly added to pesticides to help them spread, adhere to targets, disperse appropriately, prevent drift and so on – caused no significant, immediate toxicity to honeybees. However, when the pesticide acetamiprid was mixed with adjuvants and applied to honeybees in the laboratory, the toxicity was quite significant and immediate: the mortality was significantly higher than for control groups. Additionally, flight intensity, colony intensity and pupae development continued to deteriorate long after the application comparative to the control groups.

Research reveals how bee-friendly limonoids are made

Image of leaf cluster.

(John Innes Centre) The best known limonoid, azadirachtin, is famous for being bee-friendly yet having a strong anti-insect effect. Due to the complex chemical structure of limonoids, it is difficult to chemically synthesize these natural products. As a result, their use is currently limited to what can be extracted from plant materials. “If this engineering could be achieved, then crops could be developed with an inherent resistance to insects, which could reduce reliance on chemical application for crop protection.”