A recent study has shown that tree pollen may have the ability to travel or drift long distances and still be able to germinate. This may have implications US Department of Agriculture may approve the development of transgenic trees. The long distance viability of germination for tree pollen may pose a problem in trying to contain the spread of future genetically modified trees in the future if and when they get USDA approval in the future.
The new research involved the study of tree pollen from the loblolly pine, considered as the most planted tree in the southern United States. The loblolly pine or Pinus taeda covers around 60 million of land area in the southern United States. It provides more than 15 percent of the worlds timber supply with over a billion pines planted each year.
The researchers have wondered whether tree pollen from such trees can survive drifting long distances and still have that ability to germinate and result in more trees being grown in other areas. According to biologist Claire Williams of the Forest History Society and the National Evolutionary Synthesis Center in Durham, North Carolina, "Long-distance dispersal of transgenic pine pollen is a potential problem only if that pollen is viable."
In order to determine how far and how high pine pollen can travel and still germinate, Williams and her colleagues used a hand held device called a spore sampler which captures and analyzes pollen found miles away from the mainland. By conducting sampling from helicopters and boat ferries, the researchers have found viable tree pollen as high as 2000 feet in the air and as far as 25 miles offshore. Prior to this, the highest pine pollen that was found in the atmosphere was only at 1000 feet.
The researchers also discovered that more than 50 percent of pine pollen that has drifted through such distances . One other thing that they found out is that pollen germination did not decline even as the distance increased. "You would expect germination to gradually drop off as pollen floats further away, but that’s not the case," Williams added.
The said research, which was funded by the USDA, showed that a single tree may have the ability to send its DNA information through its pollen dozens of miles away. This would make it difficult for preventing the sharing of traits between genetically modified trees of the future with those trees from the natural environment. There might also be a higher risk of cross pollination between pines which might have a significant impact on the forest ecosystem. Although transgenic tress have not yet been approved for commercial use, there are already some that are being planted for field trials.