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Role of Hydropriming and Magneto-Priming in Developing Stress Tolerance

be used as a feasible and chemical free solution to address crop productivity

under non-stress and stressed environments like drought, salinity, UV B

radiation, nutrient deficiency, and heavy metal toxicity, etc. (Mirdha et al.,

2016; Razmjoo & Alinian, 2017; Baghel et al., 2018; Hozayn et al., 2018;

Kataria & Jain, 2019; Islam et al., 2020; Kataria et al., 2020a, b, 2021; Fatima

et al., 2020; Prajapati et al., 2020; Sarraf et al., 2020).

4.3 MAGNETO-PRIMING FOR IMPROVING PLANT PERFORMANCE

UNDER ABIOTIC STRESSES

Magneto-priming of the seeds has helped in improving the abiotic stress

tolerance which the crop experiences pre- and post-germination. It becomes

more relevant as remedies for early plant growth under soil-related limita­

tions help in crop establishment that may be protected from later events of

stress, like high/cold temperatures, by other strategies. We have discussed

in detail the beneficial effects of magneto-priming towards various abiotic

stresses under the different subheadings.

4.2.1 SALT STRESS

Salinity adversely affects seed germination and early seedling growth leading

to reduced productivity in crops (Nawaz et al., 2012; Kataria & Verma, 2018).

It lowers the osmotic potential, prevents water uptake and/or causes Na⁺

toxicity that prevents successful germination of the seeds (Khajeh-Hosseini

et al., 2003). Similar to other abiotic stresses, ROS mediated oxidative stress

results in malfunctioning of the cellular machinery (Ozgur et al., 2013;

Kataria & Verma, 2018) by harming the biomolecules such as proteins,

lipids, and nucleic acids (Gill & Tuteja, 2010). Application of compatible

solutes via seed priming was observed to enhance salinity tolerance (Hare et

al., 1998; Hasegawa et al., 2000; Sen & Puthur, 2020) due to accumulation

of stress-induced compounds like free proline and malondialdehyde (MDA);

antioxidant enzymes such as SOD, CAT, peroxidase (POD); ionic homeo­

stasis and hormone regulation (Iqbal & Ashraf, 2010; Sen & Puthur, 2020).

El-Yazied et al. (2011) observed that magneto-priming of tomato seeds

resulted in a significant increase in the germination percentage and reduced

the time needed for germination. This was validated in another study on

chickpea and barley where magneto-priming had the potential to overcome

the adverse effects of salinity at germination and early seedling growth stage

(Thomas et al., 2013; Hozayn et al., 2018). Germination tolerance index