(The Center Square) — When bees visit flowers, they get food and emit waste. Bees release microbes during this process, which can alter their gut microbiome. Scientists thought that monocultures such as sunflower fields would lead to the restructuring and homogenization of bees’ gut bacteria. It turns out, not so much.
However, bees visiting such monocultures didn’t lose gut biome diversity, according to Lauren Ponisio, an assistant biology professor in the College of Arts and Sciences and Institute of Ecology and Evolution.
“It’s a hopeful story for bees living in these industrial agricultural systems because they still seem to be able to acquire the microbes they need from different places,” Ponisio said in a release. “They don’t just lose all their diversity due to mass-blooming crops.”
In a research paper published on February 27 in the journal Molecular Ecology, the researchers examined the results of their visits to sunflower fields in Yolo County in Northern California, west of Sacramento.
“These fields are definitely interesting places to work,” Gordon Smith, a former UO postdoctoral researcher, said in the release. “It’s you, your big sun hat, and your insect net, and you’re trying to take a look at what kinds of bees are visiting these plants.”
These sunflower farms attract various types of bee species during their bloom season. During that time, the farms become a hub for pollen, waste, beneficial microbes, and parasites.
The spread of disease is one of the top causes of population decline among insect pollinators. Bee guts have not received much study, unlike human gut microbiome.
“We know from all the work in human gut microbiomes that the composition, the relative abundance of different microbial species, alone can have large impacts on things like your mood, food digestion, and food preferences,” Smith said. “There are a lot of nuanced effects on your behavior just based on what’s living in your gut. But what are those more subtle effects in bees, and where do their microbes come from?”
While sunflower monoculture didn’t have much impact on bee microbiomes, further research done by the team found it amplified the prevalence and spread of some infectious parasites. That impact decreased if there were more diverse flowers nearby.
No one knows if all mass-blooming crops amplify parasitism. However, installing strips of diverse vegetation called hedgerows “can support bees as an alternative resource and protect against infection,” a release said.
Ponisio and her lab want to improve agriculture for wildlife and people via land restoration and enhancement. She wants to explore more diverse systems, including high-elevation meadows, to better understand how species differences impact their gut microbiomes.
“Just as we need to work to preserve the habitats bees live in,” she said in the release, “we also need to work to preserve the habitats living within bees.”
Funding from the Foundation for Food and Agriculture Research, a group focused on public-private partnerships, supported this research.
