Pesticides used to help bees may actually harm them

August 08, 2016

Pesticides beekeepers are using to improve honeybee health may actually be harming the bees by damaging the bacteria communities in their guts, according to a team led by a Virginia Tech scientist.

The discovery, published in the journal Frontiers in Microbiology, is a concern because alterations can affect the gut's ability to metabolize sugars and peptides, processes that are vital for honeybee health. Beekeepers typically apply pesticides to hives to rid them of harmful parasites such as Varroa mites.

"Although helpful for ridding hives of parasites and pathogens, the chemicals in beekeeper-applied pesticides can be harmful to the bees," said Mark Williams, an associate professor of horticulture in the College of Agriculture and Life Sciences and lead author. "Our research suggests that pesticides could specifically impact the microbes that are crucial to honey bee nutrition and health."

For the project, the team extracted genomic data from honeybees that lived in hives that were treated with pesticides (three different kinds) and compared with those that were not. Samples were pulled from hives in three separate Blacksburg locations.

Honeybees from chlorothalanil-treated hives showed the greatest change in gut microbiome, said Williams, who is also affiliated with the Fralin Life Science Institute.

Looking ahead, the team plans to investigate the specific changes in gut microbiota activities that affect honeybee survival. Honeybees are the foundation of successful high-value food production.

"Our team wants to better describe the core microbiota using bioinformatics to help best characterize the microbes that support healthy honeybees and thus stave off disease naturally," said co-author Richard Rodrigues, a postdoctoral researcher at Oregon State University and formerly a graduate student in Williams' lab.

Other authors include Troy Anderson, a former assistant professor of entomology at Virginia Tech; Madhavi Kakumanu, a postdoctoral scientist at North Carolina State University and former Virginia Tech graduate student in Williams' lab; and Alison Reeves, a former graduate student in Anderson's lab.

In Virginia, the approximate rate of hive loss is more than 30 percent per year, and continued losses are expected to drive up the cost for important crops that bees make possible, such as apples, melon and squash.
-end-
See the Virginia Tech news release.

Virginia Tech

Related Pesticides Articles from Brightsurf:

More plant diversity, less pesticides
Increasing plant diversity enhances the natural control of insect herbivory in grasslands.

In pursuit of alternative pesticides
Controlling crop pests is a key element of agriculture worldwide, but the environmental impact of insecticides is a growing concern.

Two pesticides approved for use in US harmful to bees
A previously banned insecticide, which was approved for agricultural use last year in the United States, is harmful for bees and other beneficial insects that are crucial for agriculture, and a second pesticide in widespread use also harms these insects.

Dingoes have gotten bigger over the last 80 years - and pesticides might be to blame
The average size of a dingo is increasing, but only in areas where poison-baits are used, a collaborative study led by UNSW Sydney shows.

Pesticides can protect crops from hydrophobic pollutants
Researchers have revealed that commercial pesticides can be applied to crops in the Cucurbitaceae family to decrease their accumulation of hydrophobic pollutants, thereby improving crop safety.

Honeybee lives shortened after exposure to two widely used pesticides
The lives of honeybees are shortened -- with evidence of physiological stress -- when they are exposed to the suggested application rates of two commercially available and widely used pesticides.

Pesticides increase the risk of schistosomiasis, a tropical disease
Schistosomiasis is a severe infectious disease caused by parasitic worms.

A proposal to change environmental risk assessment for pesticides
Despite regulatory frameworks designed to prevent environmental damage, pesticide use is still linked to declines in insects, birds and aquatic species, an outcome that raises questions about the efficacy of current regulatory procedures.

SDHI pesticides are toxic for human cells
French scientists led by a CNRS researcher have just revealed that eight succinate dehydrogenase inhibitor pesticide molecules do not just inhibit the SDH activity of fungi, but can also block that of earthworms, bees, and human cells in varying proportions.

Pesticides deliver a one-two punch to honey bees
A new paper in Environmental Toxicology and Chemistry reveals that adjuvants, chemicals commonly added to pesticides, amplify toxicity affecting mortality rates, flight intensity, colony intensity, and pupae development in honey bees.

Read More: Pesticides News and Pesticides Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.