Impact

On a green rooftop at Penn State, bees buzz for science

Rooftop bee colonies aid in pollinator health research

The Center for Pollinator Research relocated three honey bee hives to the roof of the Millennium Science Complex for their research. Credit: Michelle Bixby / Penn StateCreative Commons

Bees buzz in the cool morning air on the green roof of the Huck Institutes of the Life Sciences' Millennium Science Complex on Penn State’s University Park campus. Three colonies have just been moved from the apiary to their new home.

Scientists from the Grozinger Lab have moved into the building and the honey bees have come with them to be in easy reach for ongoing research projects.

One of the research projects involves studying how stressors, like poor nutrition and pesticides, may make bees more susceptible to viruses, explained Philip Moore, the outreach coordinator for Penn State's Center for Pollinator Research.

Having the colonies nearby allows researchers to pull developing bees out of the frames, put them in incubators and wait for the bees to hatch.

”This allow us to collect bees just as they emerge as brand new adults,” Moore said. “So when you inject a newly-emerged bee with a virus, you know exactly what it's history has been and you can test the impacts different stressors, without worrying that the bee has already been exposed to those stressors. It's basically a 'clean slate'.”

Injecting those brand-new bees with viruses is the job of Aine O’Sullivan, doctoral student in entomology. She uses a syringe with a glass needle to inject viruses into the abdomen or thorax of anesthetized bees.

In other experiments, O'Sullivan is testing whether artificial viruses can be used to control expression levels of specific genes in the bee, so that researchers can better test the function of those genes.

“At this stage, I’m just testing if it works using a fluorescent gene, and figuring out if we can change expression of these genes in specific tissues in the bee,” she said.

Once the researchers develop the delivery system and determine which the tissues that reliably fluoresce, they can move on to experimenting with other genes.

“It could be a really useful tool,” O’Sullivan said. “We could test the function of genes that we think may promote health and disease resistance in bees, or genes that may fight other viruses in the bee.”

In other projects, Carley Miller is using molecular tools to answer ecology questions about bee populations. Miller, a graduate student in entomology in Shelby Fleischer's research group, is an ecologist.

She is studying which bees are the primary pollinators in cropping systems throughout the United States and how strong the populations of those bee species are. In Pennsylvania, the study is looking at fields in Lancaster, Centre and Columbia counties.

“We wanted to find out how healthy the bumble bee populations are,” Miller said. “Can we rely on them to do pollination? Because right now farmers are renting a lot of honey bees to do the pollination.

“If we are able to tell them ‘your bumble bees are really strong in this area, you are going to keep having great population year after year, you don’t have to rent as many honey bees,’ that is useful when honey bees are getting really expensive,” Miller said.

To know how strong these populations are, researchers need to figure out how many colonies are sending different workers into a field to pollinate it. Testing the DNA using molecular tools is necessary because all bumble bees look similar, even if they are from different colonies.

“So we obtain the DNA from 200 bees and then we see if those bees are sisters or not,” Miller said. “If they are sisters, they come from the same colony. Then you have an idea of how many colonies are sending workers into the field to do pollination.”

Results of testing 200 bees per field show that bees from approximately 150 unique colonies are pollinating any one field in the commonwealth.

“In Pennsylvania we have a great population of wild bees,” Miller said. “And we do that with having lots of different wild flowers and different mix of plantings in small, diversified farms. We have a lot of small farms, separated by forests, and people growing several different crops. All of this makes our bees really healthy. So for the other people in the project, it’s like ‘what’s so great about Pennsylvania?’ and they want to grow the extra resources that we have. So we’re kind of the gold standard.”

 “When we figure out how strong these bumble bee populations are, we can help farmers make decisions on management practices,” Miller said. “So if we have really strong populations, we want to continue with those practices – growing wild flowers, diversified farming. So as we figure out how healthy our bees are, we can give recommendations to farmers in the area and all across the nation to make sure they also have equally strong native bee populations for pollination.”

So while these bees on the roof of the Millennium Science Complex are helping scientists learn more about how to keep colonies healthy, they will be busy going about their bee business, pollinating the flowers within reach of their new home.

Last Updated September 23, 2020