Influence of aluminum in biologic effects of ELF magnetic field stimulation

We studied the influence of a weak, extremely low-frequency magnetic field (MF) with a frequency of 50 Hz and a peak amplitude of 103 mu T and aluminu m solution (in the form of AlCl3) at different concentrations (0, 40, 70, 1 00, 130, 160, 400, 800, 2000, and 5000 mu M) on the growth of spruce seedli ngs (Picea abies). The results showed that stimulatory and statistically si gnificant MF effects on the growth of seedlings were observed only with a 1 00-mu M aluminum solution. Slight stimulative effects were also observed wi thin the range of concentrations between 40 and 160 mu M Al3+ (all the stim ulated groups taken together). Germination and fresh weight were not signif icantly influenced. At these concentrations the aluminum solution alone (wi thout MF) or the MF alone (without Al3+) did not influence the growth param eters. These results suggest the importance of synergistic action of the MF with environmental factors as well as the existence of "physiologic window s" in addition to the frequency and power ones.