Effects of homeopathic arsenic on tobacco plant resistance to tobacco mosaic virus. Theoretical suggestions about system variability, based on a large experimental data set
L Betti, L Lazzarato, G Trebbi, M Brizzi, GL Calzoni, F Borghini and D Nani
Context: This research aimed at verifying the efficacy of homeopathic treatments by
plant-based bioassays, which may be suitable for basic research, because they lack
placebo effects and provide large datasets for statistical analyses.
Objective: To evaluate the effects of homeopathic treatments of arsenic trioxide (As2O3)
on tobacco plants subjected to tobacco mosaic virus (TMV) inoculation as biotic stress.
Design: Blind, randomized experiment using tobacco leaf disks.
Materials and methods: Tobacco plants (Nicotiana tabacum L. cultivar Samsun)
carrying the TMV resistance gene N. TMV inoculated leaf disks were floated for 3
days in the following:
Distilled water (control)
H2O 5 and 45 decimal and centesimal potencies
As2O3 5 and 45 decimal and centesimal potencies
The main outcome measures is the number of hypersensitive lesions observed in a leaf disk.
Results: Homeopathic treatments of arsenic induce two effects on the plant: (i) increased
resistance to TMV; (ii) decrease variability between experiments (system variability).
Conclusions: In this experimental model two actions of homeopathic treatment were
detected: decrease in system variability and enhancement of the natural tendency of
the system towards an ‘equilibrium point’. Homeopathy (2003) 92, 195–202.
Keywords: homeopathy; tobacco plants; virus infection; arsenic; resistance;
system variability