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

significantly. The plants grown from treated seeds had been observed to have

massive vegetative growth, but no significant effect was recorded in terms of

reproductive yield (Katsenios et al., 2020).

In another study, Razmjoo & Alinian (2017) treated cumin seeds to a

static magnetic field of varying strengths, i.e., 0, 150 mT, 250 mT, 500 mT,

and 1 T for 12 min. An enhancement in germination attributes and early

growth parameters was observed in all the treatments. They also reported

that the days to emergence as well as flowering and maturity had been short­

ened along with increased chlorophyll and declined proline contents under

exposure to static magnetic field. Braga et al. (2020) evaluated the impact

of MF pretreatment on the germination of coffee seeds and hence, the seeds

were treated with the magnetic stimulus of 10 mT and 28 mT for 6 days.

They suggested that seed pre-magnetization process would be an inexpensive

and effective technique since there was an improvement in the germination

uniformity along with permeability of cellular membrane and activation of

antioxidant systems under exposure to both magnetic field intensities. The

exposure of an extremely low EMF of 0.03 μT with 10 Hz frequency for 30

minutes was found to improve germination percentage with a higher accu­

mulation of antioxidant enzymes in germinating Foxtail millet seeds (Setaria

italica). The EMF treated seeds were recorded to enhance the germination

percentage by 93% with a 15.66% higher germination efficiency than the

untreated seeds (Ramesh et al., 2020). The impacts of magneto-priming on

germination and subsequent seedling growth, or associated changes have

been summarized and presented in Table 5.1.

5.2.2 IMPACTS ON PLANT GROWTH AND DEVELOPMENT

The germination and early seedling developmental stages are very critical

since these two stages ultimately determine the overall growth and develop­

ment of crop plants and ultimately its productivity. In the context of current

challenges for agricultural sustainability and food security, optimizing the

exposure duration and dose or intensity of physical agents is very pertinent.

As such the researchers are continuously engaged to find out the impact of

physical treatments including magnetic exposure on crop growth particularly

during early stages.

The growth of the cucumber (Cucumis sativus) plant was found to

increase significantly when magnetically treated water was used for irriga­

tion during the cultivation of seeds (Hirota et al., 1999). Further, magnetized