Development of Compact High-Voltage Power Supply for Stimulation to Promote Fruiting Body Formation in Mushroom Cultivation

Abstract

The compact high-voltage power supply is developed for stimulation to promote fruiting body formation in cultivating L. edodes and Lyophyllum deeastes Sing. mushrooms. A Cockcroft-Walton (C-W) circuit is employed to generate DC high-voltage from AC 100 V plug power for the compact, easy handling and high safety use in the hilly and mountainous area. The C-W circuit is connected to high-voltage coaxial cable which works for high-voltage transmission and for charging up as energy storage capacitor. The output voltage is around 50 kV with several microseconds pulse width. The dimension and weight of the developed power supply are 0.4 × 0.47 × 1 m3 and 8.1 kg, respectively. The effect of the high-voltage stimulation on enhancement of fruiting body formation is evaluated in cultivating L. edodes and Lyophyllum deeastes Sing. mushrooms using the developed compact high-voltage power supply. The conventional Marx generator is also used for comparison in effect of high-voltage stimulation for fruiting body formation. L. edodes is cultivated with hosting to natural logs and the pulsed high voltage is applied to the cultivated natural logs. The substrate for Lyophyllum deeastes Sing. cultivation consists of sawdust. The results show that the fruiting body formation of mushrooms of L. edodes for four cultivation seasons and that of Lyophyllum deeastes Sing. for two seasons both increase approximately 1.3 times higher than control group in terms of the total weight. Although the input energy per a pulse is difference with the generators, the improvement of the fruit body yield mainly depends on the total input energy into the log. The effect for promotion on fruiting body formation by the developed compact high-voltage power supply is almost same that by the conventional Marx generator.

Surface Modification to Improve Properties of Materials

“…Mushrooms represent an important nutritional component of the human diet and are valuable in many countries; therefore, the demand often exceeds the supply. A method for increased growth employs treatment of the substrates by pulsed electrical fields [48]. Several power supplies have been tested for the promotion of mushroom growth by electrical stimulation reaching voltages on the order of 100 kV [49].…”

“…The efficiency of such treatments depended enormously on the type of mushroom; therefore, an appropriate voltage has to be adopted according to particular conditions [39]. Unlike conventional methods, the innovative power supply reported in this issue by Takahashi et al [48] enabled application also in hilly and mountainous areas and resulted in a significant improvement in mushroom production.…”

Pulsed Power Applications for Protein Conformational Change and the Permeabilization of Agricultural Products

“…Figure 9 shows the schematic and photograph of a Marx circuit for agricultural applications [ 22 , 23 ]. The Marx generator consists of four 0.22 μF capacitors, charging resistors (1 and 5 MΩ) and spark gap switches.…”

“… Schematic ( a ) and photograph ( b ) of a four-stage Marx circuit for agricultural applications [ 23 ]. © MDPI 2018.…”

Pulsed power applications for agriculture and food processing

“…Figure 8 shows schematics and photograph of high-voltage power supply based on Cockcroft-Walton circuit (Green techno, Kanagawa, Japan; GM100) for agricultural applications (Takahashi et al 2018) Turining spark gap switch on gap switch on. The recovery time is limited by the impedance of converters and capacitance of the C-W circuit.…”