Featured Research

from universities, journals, and other organizations

Far-flung pine pollen still potent miles from the tree: Long-lived pine pollen might hinder containing transgenic trees

Date:
April 7, 2010
Source:
National Evolutionary Synthesis Center (NESCent)
Summary:
A new study suggests that pollen from the loblolly pine -- the most commonly planted tree in the southern US -- can still germinate after drifting long distances. The answer could have profound implications if and when the USDA approves transgenic trees. Far-flung pollen makes it difficult to prevent traits developed in transgenic trees from spreading to their wild counterparts, researchers say.

Loblolly pine forest. Horizontal composition landscape.
Credit: iStockphoto/Karl Kehm

When forest biologist Claire Williams boards ferries bound for North Carolina's Outer Banks, the barrier islands that line the NC coast, ferry captains call her the "Pollen Lady."

Each spring from 2006 to 2009, Williams traveled back and forth from the islands to the mainland, collecting pine pollen blown far offshore. She wanted to find out if pollen from the loblolly pine -- the most commonly planted tree in the southern United States -- can still germinate after drifting long distances.

The answer could have profound implications if and when the USDA approves transgenic trees. "Long-distance dispersal of transgenic pine pollen is a potential problem only if that pollen is viable," said Williams, currently at the Forest History Society and the National Evolutionary Synthesis Center in Durham, N.C.

The loblolly pine, Pinus taeda, grows on nearly 60 million acres in the southern U.S. and provides more than 15% of the world's timber. "Roughly one billion loblolly pines are planted in the American South each year," Williams said. "But right now, none are genetically modified."

During peak pollen season in late March and early April, loblolly pines shed millions of pounds of pollen into the air. Although the majority of that pollen lands nearby, a fraction floats far from the source, she explained.

Once windborne, pollen is exposed to extreme cold, UV radiation, and moisture from clouds and rain. "Pine pollen can travel up to 1800 miles in a short amount of time," said Williams. "But is it viable?"

To see 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 to capture and analyze pollen found miles from the mainland. Sampling by helicopter and by ferry, they found viable pine pollen as far as 2000 feet in the air and 25 miles offshore.

"Until then, the highest pine pollen had ever been found in the atmosphere was 1000 feet," she said.

More than 50% of pine pollen still germinates after drifting those distances, they discovered. "The odd thing is that pollen germination did not decline as distance increased," Williams explained. "You would expect germination to gradually drop off as pollen floats further away, but that's not the case."

The research, funded by the USDA, means that a single tree can send its DNA dozens of miles. This makes it difficult to prevent traits developed in transgenic trees -- such as drought tolerance and disease- and pest-resistance -- from spreading to their wild counterparts, Williams said.

Although transgenic trees have not yet been approved for commercial use, they are planted as field trials. The long life span of pines makes it difficult to evaluate the environmental impacts of these trees, Williams said. Loblolly pines can cross-pollinate with other closely related pine species, and are typically grown for 25 to 35 years before harvest, she explained. "The older a tree gets, the more pollen it produces each year."

On the other hand, potency of far-flung pollen could be good news for forests facing climate change, Williams added. "Under human-induced climate change we expect higher wind speeds and more frequent storms will move pollen and seeds even farther from the source," she said. That means that genes needed to adapt to warmer temperatures will have a better chance of mixing with populations that don't have them, she explained.

The findings were published online March 26, 2010 in the American Journal of Botany.


Story Source:

The above story is based on materials provided by National Evolutionary Synthesis Center (NESCent). Note: Materials may be edited for content and length.


Journal Reference:

  1. Williams, C.G. Long-distance pine pollen still germinates after meso-scale dispersal. American Journal of Botany, 2010; DOI: 10.3732/ajb.0900255

Cite This Page:

National Evolutionary Synthesis Center (NESCent). "Far-flung pine pollen still potent miles from the tree: Long-lived pine pollen might hinder containing transgenic trees." ScienceDaily. ScienceDaily, 7 April 2010. <www.sciencedaily.com/releases/2010/04/100405091943.htm>.
National Evolutionary Synthesis Center (NESCent). (2010, April 7). Far-flung pine pollen still potent miles from the tree: Long-lived pine pollen might hinder containing transgenic trees. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2010/04/100405091943.htm
National Evolutionary Synthesis Center (NESCent). "Far-flung pine pollen still potent miles from the tree: Long-lived pine pollen might hinder containing transgenic trees." ScienceDaily. www.sciencedaily.com/releases/2010/04/100405091943.htm (accessed July 28, 2014).

Share This




More Plants & Animals News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins