Navigation Links
Storing seeds for a rainy day -- or in this case, a fire
Date:5/31/2011

As mountain pine beetles march across the forests of western North America, these insects may kill millions of pine trees during a single outbreak. A rise in overall temperatures over the past several years has increased the range of mountain pine beetles, resulting in an epidemic and possibly making this mountain pine beetle infestation the largest forest-insect blight to occur in North America.

Dr. Francois Teste and colleagues from the University of Alberta in Canada have been investigating the effect of mountain pine beetle outbreaks on lodgepole pines in British Columbia. Teste and colleagues have discovered that seeds from cones on the forest floor may provide a viable seed bank for lodgepole pine regeneration following forest destruction by mountain pine beetles. Their research is published in a recent issue of the American Journal of Botany (http://www.amjbot.org/content/98/4/630.full).

Lodgepole pines, a variety of the pine species Pinus contorta, are a serotinous speciesthe seeds are only released from the cones in response to specific environmental conditions, in this case fire, rather than at the time of seed maturation. The seed bank of lodgepole pines is found in closed cones, which generally are located in the canopy. Following a mountain pine beetle outbreak, dead trees with canopy cones may remain standing for 10 to 15 years. However, scientists have observed a considerable increase in closed cones on the forest floor due to an increase in branch breakage after tree death. The viability of these canopy and forest-floor seeds and the likelihood that they will be able to contribute to forest regeneration has not been known.

Using germination techniques, Teste and colleagues assessed the viability of seeds from closed cones from both the canopy and forest floor of stands of trees 3 years, 6 years, and 9 years after mountain pine beetle outbreaks. These researchers found that closed forest-floor cones had high germination capacity (over 80%), but this germination capacity dropped to 45% for cones that were partly open. Although canopy cones have a >90% germination capacity a year, on average, after cone maturation, germination capacity steeply declined after 15 years and dropped to 50% after 25 years.

"Closed resin-bounded cones typical of serotinous pines can maintain (up to about 10-15 years) viable seed on dead trees even if the cones are partly open and/or in the forest floor," Teste said, "but of course the germination capacity does slowly decline with time." This is the first study demonstrating that there is a viable forest-floor seed bank for a serotinous pine species.

The serotinous adaptation of lodgepole pines allows for the regeneration of forests decimated by fire, but may be a hindrance to forests destroyed by mountain pine beetles. Although seed in closed cones may be viable following a mountain pine beetle outbreak, it cannot contribute to forest regeneration unless it is released from the cone, a process that would generally be triggered by fire.

"We can only speculate that it is a potential source for future regeneration if a ground fire or site preparation resurfaces the cones," Teste stated regarding the forest-floor seed bank. Teste's future research may focus on the impact of fire after mountain pine beetle outbreaks, specifically whether fire can promote regeneration from buried cones.

"With novel disturbances emerges novel responses to maintain ecosystem stability," Teste said.


'/>"/>

Contact: Richard Hund
rhund@botany.org
314-577-9557
American Journal of Botany
Source:Eurekalert

Related biology news :

1. Restoring the European Beaver: 50 Years of Experience by G. Sjoberg and J.P. Ball
2. MIT biologists find that restoring the gene for cancer protein p53 slows spread of advanced tumors
3. Storing carbon dioxide deep underground in rock form
4. Restoring a natural root signal helps to fight a major corn pest
5. Nottingham scientists reveal genetic wiring of seeds
6. Seedlings thrive with distant relatives, seeds with close family
7. New path to water efficient seeds opens as TIP pips PIP as water gatekeeper
8. Plants cloned as seeds
9. How spring-loaded filaree seeds self launch
10. Guardian angels for seeds
11. How some plants spread their seeds: Ready, set, catapult
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/2/2016)... -- The Department of Transport Management (DOTM) of ... US Dollar project, for the , Supply and ... and IT Infrastructure , to Decatur ... of Identity Management Solutions. Numerous renowned international vendors participated in ... was selected for the most compliant and innovative solution. ...
(Date:5/20/2016)... MINNEAPOLIS , May 20, 2016  VoiceIt ... technology partnership with VoicePass. By working ... user experience.  Because VoiceIt and VoicePass take slightly ... two engines increases both security and usability. ... expressed excitement about this new partnership. ...
(Date:4/28/2016)... India , April 28, 2016 ... Infosys (NYSE: INFY ), and Samsung SDS, a ... that will provide end customers with a more secure, ... services.      (Logo: http://photos.prnewswire.com/prnh/20130122/589162 ) , ... services, but it also plays a fundamental part in enabling ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... 23, 2016 , ... STACS DNA Inc., the sample tracking software company, today ... Laboratory, has joined STACS DNA as a Field Application Specialist. , “I am ... and COO of STACS DNA. “In further expanding our capacity as a scientific integrator, ...
(Date:6/23/2016)... Ky. , June 23, 2016 ... two Phase 1 clinical trials of its complement ... placebo-controlled, single and multiple ascending dose studies designed ... pharmacodynamics (PD) of subcutaneous injection in healthy adult ... subcutaneously (SC) either as a single dose (ranging ...
(Date:6/23/2016)... 23, 2016 Andrew ... http://doi.org/10.17925/OHR.2016.12.01.22 Published recently in ... journal from touchONCOLOGY, Andrew D Zelenetz , ... cancer care is placing an increasing burden on ... biologic therapies. With the patents on many biologics ...
(Date:6/23/2016)... Francisco, CA (PRWEB) , ... June 23, 2016 ... ... (EDC) software, is exhibiting at the Pennsylvania Convention Center and will showcase its ... Annual conference. ClinCapture will also be presenting a scientific poster on Disrupting Clinical ...
Breaking Biology Technology: