The Lightning and the Truffle

Absorption of nitrates by the plant is enhanced considerably by the truffle, because the truffle’s mycelia and ascocarps reduce nitrate at a much higher rate than the rootlets of the plant alone. This is believed to play an important role in the release of spores. It may also provide at least a partial explanation for the persistent observation made by desert truffle collectors that strong lightning during rainy thunderstorms in fall will bring out the truffles in large quantities during the spring. Nitrogen is an abundant element. About 80% of the air is nitrogen. Inorganic nitrogen may exist in the free state as nitrite (NO₂^-), nitrate (NO₃^-), or ammonia (NH₃⁺). It can also exist in the free state as a gas (N₂). During a rainstorm accompanied by lightning, a very high electrical potential is discharged instantaneously, and nitrogen can be dissociated to nitrogen atoms or nitrogen free radicals. The atoms and free radicals can form nitrogen compounds with water molecules, which include hydrogen, oxygen, and nitrogen atoms. These compounds are water soluble and are dissolved in the water drops surrounding them, which in turn carry them down to the ground. The hydrogen-nitrogen-oxygen compounds have ionic nature, and can easily form potassium salt, natrium salt, and other cationic metal salts once they hit the ground where these metal cations are available. Some of these nitrogen-hydrogen-oxygen metal salts are effective fertilizers. Those could be present in much higher concentrations in the soil after massive lightning and thunder rainstorms have occurred. It is known that fungi require nitrogen compounds in order to initiate fruiting. Maybe the persistent claim made by many local collectors that truffles abound in the areas hit by strong lightning and thunder rainstorms, has a scientific base. The Bedouins of the Negev even call desert truffles ‘the thunder fungus’.

For more reading:

• Juliet O. Ewaze, Menhel M. Al-Naama, Studies on Nitrogen Metabolism of Terfezia spp. and Tirmania spp., Phytologist, Vol. 112, No. 3 (Jul., 1989)
• Stamets, Paul, Mycelium Running, Ten Speed  Press, 2005
• Kagan-Zur, Varda, Terfezias – a Family of Mycorrhizal Edible Mushrooms for Arid Zones, Uppsala, Sweden, July 3-4, 1998,

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