Magnetic Frequency-Dependent Effects on Seed Germination and Seedling Development in Oryza saliva L. var. IR8

Abstract

The influence of 10 varying frequencies (5.0 x 10'3 Hz to 1.0 x 102 Hz) of alternating magnetic fields on Oryza saliva L. var. IR8 seed germination and seedling development were investigated. The seeds were exposed once to varying frequencies of alternating magnetic fields generated by a Helmholtz coil system. Evaluation of seed germination parameters included a five-day daily cumulative percent germination count, corrected germination rate index (CGRI) calculations, a-amylase assay and apparent amylose content determination. Evaluation of seedling development parameters included shoot and root growth rates and fresh and dry weights. The experiment showed that varying frequencies of magnetic fields promoted an early onset of seed germination and a faster germination rate. However, final germination of the seeds was not affected. The a- amylase activity and its substrate, amylose content, were also not affected. Seedling parameters, shoot and root growth rates and fresh and dry weights, were also not significantly different from the control. Positive correlations existed between early onset of seed germination and rate of germination, early onset of seed germination and seedling fresh weight, rate of germination and fresh weight. A negative correlation existed between fresh weight and root growth rate. Alternating magnetic fields may serve as a beneficial noninvasive tool to break rice seed dormancy and to increase the rate of rice seed germination.