A Preliminary Study of Bioelectrical Potential of Wild, Edible Termitomyces heimii in a Private Organic Garden in Mapusa, Goa, India

DC millivolt (mV) bioelectrical measurements were recorded in situ from fresh, undisturbed basidiocarps of Termitomyces heimii Natarajan growing gregariously at the base of a masonry structure at Mapusa, Goa, India, during the 2026 monsoon season. A handheld digital multimeter (HAOYUE DT830D) was used, with the positive electrode inserted into the centre of the hard, melanized perforatorium (umbo) of the pileus and the negative electrode inserted into the basal-most portion of the fleshy, fibrous stipe of the same specimen; no external soil grounding was used. Probe insertion produced a consistent transient voltage spike that stabilized within approximately five minutes to a baseline value, after which minor residual fluctuations of 1–5 mV persisted. Smaller basidiocarps stabilized at 4–6 mV, while larger basidiocarps stabilized near 14 mV, with a wider pre-stabilization fluctuation range of 15–46 mV. One reading of 88.9 mV was recorded as a transient artefact that crashed and restabilized within the expected range for that specimen and was excluded from summary statistics. Attempts to record resistance (Ω) and current (A) with the same instrument returned out-of-range (overload) values at every setting. Excavation of representative specimens confirmed that the epigeal basidiocarps were connected via a pseudorrhiza (approximately 0.5 m in length, variably twisted around subterranean obstacles) to a hypogeal fungus comb via a basal disc, in the sense described by Heim (1977). This is, to our knowledge, among the first reports of a perforatorium-to-stipe-base bioelectrical potential measurement in a termitophilic Basidiomycete, and is offered as a preliminary, exploratory pilot study. We propose that similar measurements be extended systematically to healthy T. heimii, T. manmiformis, and other Termitomyces basidiocarps encountered in future field seasons.