Extremely low doses of arsenic affect in vitro pollen germination

Introduction: This study deals with the effects of extremely low doses or high dilutions of pharmacological compounds on in vitro pollen germination of kiwifruit (Actinidia deliciosa). Material and Methods: The biological efficacy of As2O3 at the 5th and 45th decimal dilution/succussion level (As 5x and As 45x) was tested on pollen previously stressed with As2O3 150 or 200 μM. The outcome variable was the pollen germination rate, as detected blind after 3 h 30 min by an Axioplan microscope. Results: A directionally consistent recovery of germination percentage was observed in both As 5x and As 45x after stressing with As2O3 150 μM. When pollen was stressed with As2O3 200 μM only as 45x induced a general and significant germination increase. Conclusions: Our results suggest that both treatments might partially remove the inhibitory effect caused by the stressor. Similar effects were observed on the same model using weak extremely low frequency magnetic fields (ELF-MFs) mediated through water. Although preliminary, the findings seem to indicate the in vitro pollen performance as adequate to study the effects of physicochemical subthreshold stimuli (extremely low doses or high dilutions of pharmacological compounds, weak ELF-MFs), mediated through water.