Posted in May 2010
Lightning boosts mushroom crop yield
Posted on 14 May, 2010
Shiitake mushroom crops double when exposed to bursts of lightning-like electricity.
Recent research from Iwate University suggests there may be some truth to old Japanese farming legends that claim lightning causes mushrooms to multiply.
In studies conducted over the past four years, Iwate University researchers -- led by Associate Professor of Engineering, Koichi Takaki -- have found that mushroom crop yields can be improved by applying high-voltage electricity to logs seeded with spores. So far, the team has studied ten mushroom species and found that bolts of lightning-strength electricity improve the crop yields for eight of those species.
Nameko and shiitake mushroom crops have demonstrated the most significant improvements after electrical stimulation. Under the best conditions, the nameko crop yield improved 80%, while the shiitake crop yield doubled.
Repeated tests have demonstrated that the mushrooms react best when exposed to 50,000 to 100,000 volts of electricity for one ten-millionth of a second. These pulses of electricity are significantly weaker than that of natural lightning, which can carry up to a billion volts of electricity -- enough to completely destroy the mushrooms with a direct hit. The gentler electrical bursts used by the researchers are comparable to that of a nearby lightning strike that has been weakened after traveling through the soil.
The findings indicate that mushrooms exposed to electricity produce greater amounts of reproductive enzymes and proteins, resulting in an increased yield. Although the exact reason for this reaction is unclear and is still under investigation, the researchers suggest it may be a response to danger. The mushrooms may be giving themselves a reproductive boost to maximize their chance of survival when they sense lightning.
The equipment now used by the researchers to produce the artificial lightning is specialized and complicated, but they eventually hope to make it more user-friendly so that it can be used by commercial farmers.
- Lightning Makes Mushrooms Multiply [National Geographic]