Following up on my earlier post about imported bumblebees escaping from their greenhouses and spreading pathogens in the native bee community, we have new research about how bees could facilitate the transport of genetically modified material from introduced, cultivated plants to native plants.
The research is related to the planned use of insect-resistant genetically engineered cowpea in Africa, where cowpea’s wild relative is widely distributed. While they don’t say this in the article, the cowpeas have a Bt gene inserted that kills caterpillar larvae. (It’s originally derived from a bacteria, and you can buy Bt over the counter in a variety of forms.)
So, it’s a biological control that will make pesticide sprays not needed–why isn’t this a good thing?
It is, BUT:
if the gene that makes the plants insect-resistant spreads and becomes very common, insects are much more likely to become resistant to it. And then our nifty, environmentally friendly tool is busted.
The scientists used radio tracking to follow the movements of carpenter bees (Xylocopa flavorufa), a big solitary bee, to see how far they flew. If the bees were homebodies, they might be less likely to spread pollen, and the new insecticidal gene.
“From complete flight records in which bees visited wild and domesticated populations, we conclude that bees can mediate gene flow and, in some instances, allow transgene (genetically engineered material) escape over several kilometers. However, most between-flower flights occur within plant patches, while very few occur between plant patches.”
So, while long distance foraging is relatively rare, it does happen, which means the gene will almost certainly be spread eventually (unless the plant produces sterile pollen). Making GMO plants have sterile pollen would be a really smart thing to do; it isn’t always possible though.
I have included the photo of a bee and her antenna from the paper, since it isn’t open access. Hopefully they won’t sue me, but I thought it was neat enough you’d like to see it.
Also, once again Science Daily screwed up and showed a photo of the wrong insect. This study was on carpenter bees, and they covered it with a honeybee photo. Grrr.
R. S. Pasquet, A. Peltier, M. B. Hufford, E. Oudin, J. Saulnier, L. Paul, J. T. Knudsen, H. R. Herren, P. Gepts (2008). Long-distance pollen flow assessment through evaluation of pollinator foraging range suggests transgene escape distances Proceedings of the National Academy of Sciences, 105 (36), 13456-13461 DOI: 10.1073/pnas.0806040105