ABSTRACT
In previous multicentre studies, the influence of a homeopathic ultra-high dilution of gibberellic acid on wheat growth was scrutinized. Data showed that this test dilution slowed down stalk growth when experiments were performed in the autumn season. The aim of this work was to test the hypothesis that pretreatment of grains with high concentrations of gibberellic acid would enhance the growth-inhibiting effect of the ultra-high dilution of the plant hormone. Grains of winter wheat (Triticum aestivum, 500 or 1000 per group) were pretreated with (non-agitated) gibberellic acid 10-5, 10-4 and 10-3 parts by weight (Ge-5, Ge-4, Ge-3) or with water (?W0?) for control prior to further treatment. Grains were then observed under the influence of extremely diluted gibberellic acid (10-30 parts by weigth) prepared by stepwise dilution and agitation according to a protocol derived from homeopathy (?G30x?). Analogously prepared water was used for control (?W30x?). Seedlings were allowed to develop under standardized conditions for 7 days; plants were harvested and stalk lengths were measured. Of the four pretreatment variants under study, Ge-3 yielded most growth, followed by Ge-4 , Ge-5 and finally W. This outcome was modulated by the application of G30x in that the inhibition obtained with G30x as compared to W30x was the greater the lower the pretreatment concentration of G had been. The hypothesis that pretreatment of grains with high concentrations of gibberellic acid would enhance the growth inhibiting effect of G30x had to be rejected. Rather, G30x slowed down stalk growth most in the W0 group with p < 0.001, only moderately in the Ge-5 and Ge-4 group and not at all in the Ge-3 group.