Effects of power frequency electromagnetic fields on growth of germinating Vicia faba L., the broad bean

Experimental investigations were carried out to evaluate the effect of continuous and delayed exposure of power frequency electromagnetic fields at 5, 50 and 100 mu T on germinating Vicia faba seedlings as a model system. These studies included physical parameters (length and girth of primary roots, number as well as length of lateral roots and imbibition), major biochemical constituents (total sugar, protein, and fat) and activities of important housekeeping enzymes (amylases, proteases, and lipase) at 2, 4, and 8 days of growth. Also, mitotic index and rate of DNA synthesis were studied at day 8 of growth. There was no significant change in physical parameters and major biochemical constituents between control and experimental groups. Also, the comparison between the control and experimental group of seeds showed that a-amylase activity significantly decreased at 5, 50 and 100 mu T on day 2 and 4 of growth. beta-amylase and protease (37 degrees C & 50 degrees C) showed a significant decrease in activity on day 2 and 4 of growth at 100 mu T, whereas activity of lipase significantly decreased only on day 2 of growth at 100 mu T. At day 8 of growth, all enzyme activities reverted back to the same as control. Also, there was a significant increase in mitotic index as well as 3 H-thymidine uptake at 100 mu T delayed exposure on day 8. The present study suggests that exposure to power frequency electromagnetic fields up to 100 mu T on germinating seedlings does not cause any permanent damage since the initial alteration under the magneticfields in some important housekeeping enzymes involved in the onset of seed germination were returened to control values on day 8 of growth. Also, the growth of the germinated seedlings was found to be enhanced by the application of power frequency magnetic fields (100 mu T) as evidenced by mitotic index and 3 H-thymidine uptake.