Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Corn fungus is nature’s master blaster

26.07.2005


Biologists have discovered that a common corn fungus is by far nature’s most powerful known cannoneer, blasting its spores out with a force of 870,000 times the force of gravity. Farmers need not worry about being nailed by a fungal supergun, however. The infinitesimal spore travels only two-tenths of an inch (5 millimeters) before plummeting.



Nevertheless, said the biologists, the fungus Gibberella zeae outguns the previous record holder, the fungus Pilobolus, by almost a hundred-fold. It also outperforms a rifle, which launches its bullet with less than one-tenth that acceleration.

The researchers -- Frances Trail and Iffa Gaffoor of Michigan State University, and Steven Vogel of Duke University -- published their findings in the June 2005 issue of Fungal Genetics and Biology. The study was supported by the U.S. Department of Agriculture and the Michigan Agricultural Experiment Station.


According to Vogel, the "bioballistics" of the fungus offers a dramatic lesson in the physics of scaling. At the infinitesimal scale of the fungus’ spore, atmospheric drag plays an enormous role -- hence the need for an extremely high ejection speed to achieve even the most modest dispersal of its spore.

"To get a literal feel for a world in which drag makes more impact than does gravity, just inflate a six-inch balloon and throw it as hard as you can," said Vogel.

The purpose of the study that revealed the fungus’s extraordinary launch capabilities was to better understand the biological mechanism behind the fungal supergun. Basically, the gun is powered by the buildup of pressure inside the spore-containing fungal fruiting body, called the perithecium, due to the ability of sap to create an osmotic pressure. Such pressure is due to water flowing across a membrane into the perithecium as it tries to equalize the concentration of a salt solution inside the chamber. In the case of the fungus, at question was whether the sugar mannitol or potassium ions were responsible for the osmotic pressure that generated the propulsive force.

In their experiments, Trail and Gaffoor created a fungal "shooting gallery" consisting of a small glass chamber, in which they mounted a block of gel-like agar containing mature perithecia. They arranged the agar so that the perithecia would launch their spores onto a removable glass cover slip. The researchers measured the length of the fungal blasts and calculated the mass of the spore. That mass turned out to be very low for a fungal spore, explaining why the fungus could achieve such extraordinary launch speeds, said Vogel. He fed data from the laboratory experiments and spore mass calculations into a computer program he had developed to determine the ballistics of such projectiles. One result was the record acceleration of 870,000 times gravity for the spores and a launch speed of nearly 80 miles an hour.

The analysis of the fungal shooting ability led the biologists to determine that the osmotic pressure from potassium, and not the mannitol, likely generated the force necessary for the powerful blast.

Vogel said he originally created the bioballistics program to demonstrate to his undergraduate classes how drag and other factors affect the trajectories of natural projectiles -- from kangaroo rats to locusts to fleas to fungal spores.

"The big animals aren’t so interesting in terms of drag," said Vogel. "But when you get down to a flea, it loses about eighty percent of potential range to drag. And the optimum launch angle gets lower. In physics class, people are taught that the best angle is forty-five degrees, but when drag is bad, the angle needs to be lower -- you want to achieve some distance while you still have decent speed. Altitude no longer gives much advantage. Thus, in the fungus the launch angle is barely above horizontal," he said.

"An obvious question is why the fungus even bothers. Given the short range of its spores, why bother accelerating to eighty miles per hour to go a mere five millimeters?," said Vogel. "Since there is almost no air movement at the surface where the spore grows, the real object of the launch is to get the spore even a little ways from the parent, so that it can get into air currents, which will really give the spore some range."

Dennis Meredith | EurekAlert!
Further information:
http://www.duke.edu

More articles from Life Sciences:

nachricht Bioenergy cropland expansion could be as bad for biodiversity as climate change
11.12.2018 | Senckenberg Forschungsinstitut und Naturmuseen

nachricht How glial cells develop in the brain from neural precursor cells
11.12.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

Im Focus: Substitute for rare earth metal oxides

New Project SNAPSTER: Novel luminescent materials by encapsulating phosphorescent metal clusters with organic liquid crystals

Nowadays energy conversion in lighting and optoelectronic devices requires the use of rare earth oxides.

Im Focus: A bit of a stretch... material that thickens as it's pulled

Scientists have discovered the first synthetic material that becomes thicker - at the molecular level - as it is stretched.

Researchers led by Dr Devesh Mistry from the University of Leeds discovered a new non-porous material that has unique and inherent "auxetic" stretching...

Im Focus: The force of the vacuum

Scientists from the Theory Department of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science (CFEL) in Hamburg have shown through theoretical calculations and computer simulations that the force between electrons and lattice distortions in an atomically thin two-dimensional superconductor can be controlled with virtual photons. This could aid the development of new superconductors for energy-saving devices and many other technical applications.

The vacuum is not empty. It may sound like magic to laypeople but it has occupied physicists since the birth of quantum mechanics.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

Expert Panel on the Future of HPC in Engineering

03.12.2018 | Event News

 
Latest News

Some brain tumors may respond to immunotherapy, new study suggests

11.12.2018 | Studies and Analyses

Researchers image atomic structure of important immune regulator

11.12.2018 | Health and Medicine

Physicists edge closer to controlling chemical reactions

11.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>