Stimulatory growth effect of lightning strikes applied in the vicinity of shiitake mushroom bed logs

Abstract

Since ancient times, the anomalous occurrence of mushrooms has been observed in and around locations struck by lightning. Based on this phenomenon, various cultivation techniques using a high voltage to cultivate shiitake mushroom in bed log (wood) have been proposed. Undoubtedly, the fruiting capacity of shiitake mushrooms is significantly promoted by direct application of a high voltage to the cultivation bed logs. However, mushroom bed logs are rarely struck directly by lightning in the natural environment. Thus, it is important to devise a stimulation method that matches conditions in the natural environment. In this study, we performed experiments involving indirect lightning strikes using a new method that mimics the natural environment as closely as possible. Specifically, we used the electric discharge created by an impulse voltage generator to create lightning but did not apply it directly to the cultivation bed log. Instead, the cultivation bed logs were placed a few meters away from the lightning rod. Subsequently, the fruiting capacity of the shiitake mushrooms with and without the indirect lightning strikes was compared. The experimental results indicated that, with the indirect lightning strikes, the extent of shiitake fruiting almost doubled compared to the case without the indirect lightning strikes. Furthermore, the results confirm that an increased shiitake mushroom production is possible using lightning strikes, even if the associated high voltages are not applied directly to the bed logs.

Investigation of stimulated growth effect using pulsed cold atmospheric plasma treatment on Ganoderma lucidum

“…The research of Shimizu et al, which treated mushrooms indirectly by simulating lightning, revealed that the yield of mushrooms improved along with increased energy that imposes on the culture medium within reasonable limits [31]. The possible reasons were mainly the effect of the electric field and pressure waves generated owing to the thermal expansion of air during lightning strikes.…”

“…Recently, Shimizu et al simulated natural lightning using a pulse voltage generator and stimulated shiitake mushroom logs without direct lightning application to the cultivated bed logs. They found that lightning promoted the growth of mushrooms [31]. Therefore, based on these investigations, we aimed to study the possible effect of plasma treatment on the growth of G. lucidum.…”

Vibrations and mushrooms: Do environmental vibrations promote fungal growth and fruit body formation?

“…Singer.) fruit body formation (Shimizu et al, 2020; Takaki et al, 2010); the authors hypothesized that stress caused by these mechanical stimuli triggered fungi to disperse away from an inappropriate habitat. In addition, Japanese mushroom farmers beat shiitake mushroom logs or beds to accelerate fruit body formation (Ito, 1964).…”

Pulsed power applications for agriculture and food processing

“…Shimizu et al reported the improvement of harvest yielding of mushroom (L. edodes) by stimulation using shockwave generated by long-gap pulse arc discharge (Shimizu et al 2020). The artificial lightning impulse voltage was generated by an impulse voltage generator (IG), was applied to rod type high-voltage electrode to generate long-gap discharge.…”