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Biology and Biotechnology of Environmental Stress Tolerance in Plants, Volume 3

magnetic fields with low and intermediate frequencies on biological compo­

nents have been attractive to the researchers in recent times, and this has

created a new wave of fervor among researchers on how the magnetic field

plays a role in plant growth and development. Thus, magneto-priming is

now gaining importance as effective and environment friendly technology-

supported physical treatments of seeds. It is one of the advanced techniques

of agronomical importance since magnetic field exposure brings out various

positive influences such as increased germination rate and seed vigor, higher

growth, enhanced crop yield as well as improved tolerance to abiotic stresses.

5.2.1 GERMINATION

The application of a magnetic field can break the dormancy of seeds, and

subsequently improves the growth rate of different crop species like barley,

maize, beans, wheat, and some fruit or other tree species. Further, a magnetic

field of 16 Hz has been reported to be an effective method for improving the

post-harvest quality of seeds of diverse plant species, specifically for low-

temperature sensitive germinating seeds species (Rochalska & Orzeszko-

Rywka, 2005).

Hornwort (Cryptotaenia japonica) showed higher cellular function

and enzymatic activity during the germination stage when the seeds were

exposed to ultra-low frequency magnetic field alongside planetary GMF

varying with sinusoidal time. This leads to assuming the possibility of the

existence of optimum extremely low-frequency MF within the planetary

geomagnetic field for improved germination of hornwort seeds (Kobayashi

et al., 2004). The outcomes particularly in terms of germination percentage,

emergence index or vigor index have been found to be satisfactory when

pea seeds (Pisum sativum) are treated with the rectified sinusoidal magnetic

field of varying strength 60, 120, and 180 mT for three fixed time periods of

5, 10, and 15 minutes (Jamil & Ahmad, 2012). A significant upregulation of

germination magnetic constant or other traits like transition time and water

uptake along with an indication of the possibility of off-season germination

has been recorded upon exposure of mungbean (Vigna radiata) seeds to the

increasing intensity of static MF ranging from 87 to 226 mT for 1 hour and

40 mins (Mahajan & Pandey, 2014).

The exposure of chickpea (Cicer arietinum) seeds to an MF strength

ranging between 0 mT and 250 mT for 1 to 4 hours at an interval of 50

mT has recorded a significant increase in germination speed along with the