Consternation amongst growers over tighter European regulations which have limited pesticide options could be eased by the discovery of a new 'bee safe' bio-pesticide.

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Newcastle University researchers announced on Wednesday that a new insect-specific bio-pesticide made from spider venom and a plant protein from snowdrops has been found to be safe for honeybees - despite being highly toxic to a number of key insect pests.

The new bio-pesticide, called Hv1a/GNA, is a combination of a natural toxin from the venom of an Australian funnel web spider and snowdrop lectin. In tests, the compound did not affect honeybees, even when the bees were fed doses higher than they would ever be expected to encounter in the field. The Newcastle team said "feeding acute and chronic doses to honeybees… had only a very slight effect on the bees' survival and no measurable effect at all on their learning and memory."

Certain Neonicotinoid pesticides, which were made subject to a tight three-year restriction in December have been linked with effects on bee health, most recently research from Harvard University suggested the pesticides – amongst the most widely used crop protection products in the world – could be playing a role in colony collapse disorder. Other research has suggested that sub-lethal doses of the pesticides could be affecting bees' ability to forage effectively.  

On publishing their findings, the Newcastle team said their novel compound has "huge potential" as an environmentally-benign, 'bee-safe' bio-pesticide and an alternative to neonicotinoids, which have been linked to declines in pollinator populations. The Newcastle researchers were working with colleagues from Durham University and FERA.

Professor Angharad Gatehouse, who oversaw the project, commented, "Our findings suggest that Hv1a/GNA is unlikely to cause any detrimental effects on honeybees. Previous studies have already shown that it is safe for higher animals, which means it has real potential as a pesticide and offers us a safe alternative to some of those currently on the market."

Bee study

During the study, bees were exposed to varying concentrations of the spider/snowdrop bio-pesticide over a period of seven days.  Throughout the study period, the team carried out a series of memory tests and recorded any changes in the insects' behaviour.

The pesticide is taken up in a different way to many others; Erich Nakasu, from Newcastle University, explained, "This is an oral pesticide so unlike some that get absorbed through the exoskeleton, the spider/snowdrop recombinant protein has to be ingested by the insects."

Unlike other pesticides, Hv1a/GNA also affects other areas - calcium channels.  These are more diverse than commonly-targeted insecticide receptors, such as sodium channels, and therefore offer the potential for more species-specific pesticides, according to the researchers.

"Calcium channels are linked to learning and memory in bees so it's vital that any pesticide targeting them does not interfere with this process," Erich added. "Although Hv1a/GNA was carried to the brain of the honeybee, it had no effect on the insect which suggests the highly selective spider-venom toxin does not interact with the calcium channels in the bee."

Bee larvae were also unaffected by the Hv1a/GNA, as they were able to break it down in their gut.

Dr Geraldine Wright, one of the authors on the paper, heads up Newcastle University's Honeybee Lab.  Last year she led the research which highlighted the damaging effect of neonicotinoids on bees' ability to learn and remember and subsequently communicate to their hive mates. "Around 90pc of the world's plants are directly or indirectly reliant on pollinators to survive," she said on Wednesday.  "If we destroy the biodiversity of pollinators then it will be irrelevant how effective our pesticides are because we won’t have any crops to protect.

"There is now substantial evidence linking neonicotinoid pesticides to poor performance and survival in bees and what we need now is a clear directive from Government to develop and introduce bee-safe alternatives."

Project supervisor Professor Gatehouse added, "There isn't going to be one silver bullet.  What we need is an integrated pest management strategy and insect-specific pesticides will be just one part of that."