Growth characteristics of mung beans and water convolvuluses exposed to 425-MHz electromagnetic fields

Effects of high-frequency, continuous wave (CW) electromagnetic fields on mung beans (Vigna radiata L.) and water convolvuluses (Ipomoea aquatica Forssk.) were studied at different growth stages (pre-sown seed and early seedling). Specifically, the effects of the electromagnetic source's power and duration (defined as power-duration level) on the growth of the two species were studied. Mung beans and water convolvuluses were exposed to electromagnetic fields inside a specially designed chamber for optimum field absorption, and the responses of the seeds to a constant frequency at various power levels and durations of exposure were monitored. The frequency used in the experiments was 425 MHz, the field strengths were 1 mW, 100 mW, and 10 W, and the exposure durations were 1, 2, and 4 h. Results show that germination enhancement is optimum for the mung beans at 100 mW/1 h power-duration level, while for water convolvuluses the optimum germination power-duration level was 1 mW/2 h. When both seed types were exposed at the early sprouting phase with their respective optimum power-duration levels for optimum seed growth, water convolvuluses showed growth enhancement while mung bean sprouts showed no effects. Water content analysis of the seeds suggests thermal effects only at higher field strength.