Bioelectromagnetics 32:474 ^ 484 (2011) Enhancement of Germination, Growth, and Photosynthesis in Soybean by Pre-Treatment of SeedsWith Magnetic Field M.B. Shine, 1 * K.N. Guruprasad, 1 and Anjali Anand 2 1 School of Life Sciences, Devi Ahilya University, Indore, India 2 Nuclear Research Laboratory, Indian Agricultural Research Institute, Pusa, New Delhi, India Experiments were conducted to study the effect of static magnetic fields on the seeds of soybean (Glycine max (L.) Merr. var: JS-335) by exposing the seeds to different magnetic field strengths from 0 to 300 mT in steps of 50 mT for 30, 60, and 90 min. Treatment with magnetic fields improved germination-related parameters like water uptake, speed of germination, seedling length, fresh weight, dry weight and vigor indices of soybean seeds under laboratory conditions. Improvement over untreated control was 5–42% for speed of germination, 4–73% for seedling length, 9–53% for fresh weight, 5–16% for dry weight, and 3–88% and 4–27% for vigor indices I and II, respectively. Treatment of 200 mT (60 min) and 150 mT (60 min), which were more effective than others in increasing most of the seedling parameters, were further explored for their effect on plant growth, leaf photosynthetic efficiency, and leaf protein content under field con- ditions. Among different growth parameters, leaf area, and leaf fresh weight showed maximum enhancement (more than twofold) in 1-month-old plants. Polyphasic chlorophyll a fluorescence (OJIP) transients from magnetically treated plants gave a higher fluorescence yield at the J–I–P phase. The total soluble protein map (SDS–polyacrylamide gel) of leaves showed increased inten- sities of the bands corresponding to a larger subunit (53 KDa) and smaller subunit (14 KDa) of Rubisco in the treated plants. We report here the beneficial effect of pre-sowing magnetic treat- ment for improving germination parameters and biomass accumulation in soybean. Bioelectro- magnetics 32:474–484, 2011. ß 2011 Wiley-Liss, Inc. Key words: magnetic field; photosynthesis; soybean INTRODUCTION Crop yields can be maximized by establishment of an adequate and uniform plant population for which good quality seed is a pre-requisite. The gains from agronomic inputs are drastically reduced if the seed is of poor quality, resulting in a poor stand. Pre-sowing seed treatment including chemical and physical treat- ments is known to improve seed performance in the field [Parera and Cantiliffe, 1994; Pill, 1995]. The beneficial effects of static and oscillating magnetic fields of very low to high field intensity have been reported in different plant species. Germination characteristics of maize seeds exposed to magnetic fields were enhanced in many studies [Pittman, 1965; Aladjadjiyan, 2002; Florez et al., 2007]. Gubbels [1982] observed that seed lots of flax (Linum usitatissimum L.), buckwheat (Fagopyrum esculentum Moench.), sunflower (Helianthus annus L.), and field pea (Pisum sativum L.) exposed to mag- netic fields produced earlier and more vigorous seed- lings. Bhatnagar and Dev [1977, 1978] reported improved seedling vigor due to pre-germination exposure of wheat seeds to magnetic fields of 50– 300 mT and found higher respiratory quotients and alpha amylase activity compared to control seeds. Germination energy and germination of tobacco seeds increased linearly with an induction of 0.15 T at exposures of 10, 20, and 30 min, with and without preliminary soaking [Aladjadjiyan and Ylieva, 2003]. Growth of the germinated Vicia faba seedlings was found to be enhanced by the application of power fre- quency magnetic fields (100 mT) as evidenced by mitotic index and 3 H-thymidine uptake [Rajendra et al., 2005]. Thus, magnetic treatment acts as a non- invasive external stimulant for germination of many *Correspondence to: M.B. Shine, School of Life Sciences, Devi Ahilya University, Khandwa Road, Indore 452001, India. E-mail: shinemb12@gmail.com Received for review 22 April 2010; Accepted 26 January 2011 DOI 10.1002/bem.20656 Published online 4 March 2011 in Wiley Online Library (wileyonlinelibrary.com). ß 2011Wiley-Liss,Inc.