About a month ago, just before getting into my car to head to work, I noticed that my shiny black car had taken on a completely new color without ever having visited the paint shop.  As I quickly swiped my finger across the trunk, the culprit for this sudden color change was identified – pollen!  Inevitably, every spring, pollen makes its debut in the air and coats every inanimate object in sight.  So where is all of this pollen coming from?  Your neighbor’s tree? How about the next city?  Maybe even from across the state line?

As it turns out, the answer to the question concerning the source of the pollen may actually be “all of the above.”  According to an article by Claire Williams published in the American Journal of Botany, pine pollen can travel up to 1,800 miles over a short time period.

Through collection of loblolly pine pollen blown from the outer banks of North Carolina to the barrier islands, Williams unveiled that pine pollen traveling as far as 2,000 feet in the air and 25 miles off shore maintained viability and can still germinate.  Because loblolly pine provides more than 15 percent of the world’s timber, the findings of this study could have profound implications on the approval of transgenic pine tree growth.

With pollen that maintains the ability to germinate over long distances of travel, preventing the spread of transgenic pine traits to wild pine species would become nearly impossible.  For instance, a transgenic loblolly pine tree may have specifically engineered traits for drought tolerance and disease resistance; thus, upon travel of their pollen to a location of wild pines, the pollen will cross-pollinate with the wild species, making the wild tree now have traits for drought tolerance and disease resistance as well.

Although this study may mean bad news for transgenic pines, the viability of “far-flung” pollen may actually be advantageous for forests experiencing climate change.  With higher wind speeds and more frequent storms expected with human-induced climate change, pollen will travel greater distances from their source; therefore, the genes needed to adapt to warmer temperatures will have a better chance of integrating with populations lacking the genes.

Discussion Question: Considering that plants other than pine trees use wind pollination for reproducing, will this study prevent genetic modification of other populous plant species?  Can you name of any other plant species that might not be approved for genetic modification for fear of cross-pollination with wild species?

News Article: http://www.sciencedaily.com/releases/2010/04/100405091943.htm
Paper Abstract: http://www.amjbot.org/cgi/content/abstract/ajb.0900255v1?maxtoshow=&hits=10&RESULTFORMAT=&fulltext=long+distance+pine+pollen&searchid=1&FIRSTINDEX=0&sortspec=relevance&resourcetype=HWCIT