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Magneto-Priming: A Novel Technique Towards Improved Seed Germinability
However, the magnetic field exposure has also been reported to increase
the production and activity of several ROS scavenging enzymes. There are
two types of antioxidant system viz., an enzymatic system which is medi
ated by enzymes such as superoxide dismutase (SOD), ascorbate peroxidase
(APX), catalase (CAT), glutathione peroxidase (GPOX), glutathione reduc
tase (GR), glutathione s-transferase (GST), etc., and non-enzymatic system
comprised of different phenolic compounds, carotenoids, AsA, α-tocopherol,
etc. The antioxidant systems help to minimize the uncontrolled oxidation and
thereby protect the plant from oxidative damages induced by ROS (Foyer
& Noctor, 2005). The ROS scavenging enzymes such as SOD, CAT, APX,
etc., regulate the concentration of ROS within the cell. Actually, the anti
oxidant systems maintain a critical level of ROS concentration that is called
“oxidative window” and thus allow the ROS to work as signaling molecules
(Figure 5.2). The progressive events of germination are not permitted if the
concentration of ROS is below or above the “oxidative window” (Bailly et
al., 2008). Recent findings of the higher transcript level of some genes that
are involved in the synthesis of SOD1, SOD9, NOX, and AO in germinating
seeds under MF exposure would indicate the crucial role of magneto-priming
in ROS scavenging (Anand et al., 2019).
FIGURE 5.2 MF induced activation of antioxidant systems in germinating seeds.