effect of magnetic field on seed germination and early growth of calendula officinalis l.

in order to study on effect of magnetic field on germination characteristics and early growth of marigold (calendula officinalis l.) seeds an experiment was carried out in laboratory conditions in arak university of iran. seeds were magnetically exposed to magnetic field strengths, 100 or 200 mt for different periods of time; d1 (control), d2 (1 h), d3 (6 h), d4 (12h), d5 (24 h) and d6 (continuous). mean germination time (mgt) and the time required to obtain 10, 25, 50, 75 and 90% of seeds to germinate were calculated. the germinationtime for each treatment were in general, higher than control values,in the other word in treated seeds time required for mean seed germination time increased nearly 4 hours in compared non treated control seeds. t10 for doses d3, d4 and d5 significantly higher than the control values. mean germination time significantly increased when the time of seed exposed at magnetic field treatments increased, about 3 and 2 hour, respectively. according to experiment results of seedling dry weight (sldw), seed resource depletion percentage (srdp) and shoot length (stl) showed more decrease with increasing of the exposure time in the magnetic field.