Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Natural pesticide impairs bumble bee foraging ability

09.05.2005


Pesticide levels previously thought to be safe for pollinators may prove harmful to wild bee health, according to research published in Pest Management Science this month.



The Canadian study shows that adult bumble bees exposed to the pesticide spinosad during larval development – at levels they could encounter in the environment – have impaired foraging ability. Bees are important pollinators of crops. In developed countries, approximately a third of human food is reliant on pollinating activity. Wild bees are thought to contribute significantly to this quantity. But although many pesticides are known to be toxic to bees, toxicity testing is largely restricted to direct lethal effects on adult honey bees, if tested on bees at all.

The researchers say sub-lethal effects on honey bees could be going unnoticed, and that different bee species could be also be affected. Dr Lora Morandin and colleagues at Canada’s Simon Fraser University tested the effects of different levels of spinosad on bumble bee colony health and foraging ability. Spinosad is a natural pesticide derived from the bacteria Actinomycetes. It is used in over 30 countries including North America, Canada and the UK to combat common crop pests such as caterpillars and thrips.


Bee colonies were fed the pesticide in a manner that mimicked contact in an agricultural setting. Adult bees and developing larva were exposed to spinosad in pollen. The bees’ foraging ability on an array of ‘complex’ artificial flowers made of centrifuge tubes was then evaluated. High levels of spinosad residues (about 10 times what bees should experience in the environment) caused rapid colony death. Colonies exposed to more realistic levels of spinosad in pollen did not show any lethal effects and only minimal immediate colony health effects.

However, bees that were fed realistic levels of spinosad during larval development were slower foragers. They took longer to access complex flowers, resulting in longer handling times and lower foraging rates. The bees also displayed “trembling”, which impaired their ability to land on the flowers and enter the flower tubes.

This impaired foraging ability in bumble bees could result in weaker colonies and lower pollination of crop plants, according to Dr Morandin. “Adult bees that have been exposed to a pesticide during larval development may display symptoms of poisoning that are not detected with current tests required by regulatory agencies,” she says. “In order to ensure sustainable food production, agricultural pesticides need to be safe for wild pollinators.”

The authors conclude that testing of new pesticides should include examination of lethal and sub-lethal effects on wild bees. “Testing new pesticides on some species of wild bees will aid in developing pesticides and use recommendations that minimize impact on wild bees, leading to healthier populations of bees and potentially better crop yields,” says Morandin.

Jacqueline Ali | alfa
Further information:
http://www3.interscience.wiley.com/cgi-bin/jhome/68504529

More articles from Agricultural and Forestry Science:

nachricht New research recovers nutrients from seafood process water
31.10.2018 | Chalmers University of Technology

nachricht Plant Hormone Makes Space Farming a Possibility
17.10.2018 | Universität Zürich

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

Im Focus: Nanorobots propel through the eye

Scientists developed specially coated nanometer-sized vehicles that can be actively moved through dense tissue like the vitreous of the eye. So far, the transport of nano-vehicles has only been demonstrated in model systems or biological fluids, but not in real tissue. The work was published in the journal Science Advances and constitutes one step further towards nanorobots becoming minimally-invasive tools for precisely delivering medicine to where it is needed.

Researchers of the “Micro, Nano and Molecular Systems” Lab at the Max Planck Institute for Intelligent Systems in Stuttgart, together with an international...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

In focus: Peptides, the “little brothers and sisters” of proteins

12.11.2018 | Life Sciences

Materials scientist creates fabric alternative to batteries for wearable devices

12.11.2018 | Materials Sciences

A two-atom quantum duet

12.11.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>