ABSTRACT
Plants resort to many adaptive strategies in response to abiotic environmental stresses such as salinity, dehydration, cold, heat, osmotic and UV-B stress which affect seed germination, plant growth, development, photosynthesis, and yield. Magnetopriming is a non-invasive physical stimulation of dry seeds with a static magnetic field (SMF), used to improve vigor and field emergence in seeds. This chapter discusses the protection of plants from the adverse effects of abiotic stresses, such as salinity, by SMF pre-treatment. The adverse effect of NaCl-induced salt stress has been observed on germination, growth, yield and various physiological attributes of many crop plants. The perusal of relevant literature reveals that SMF pre-treatment to the seeds significantly increased the percentage germination, early seedling characteristics, plant-growth attributes, biomass accumulation, photosynthetic performance, nitrogen fixation and yield under both non-saline and saline conditions. Chlorophyll, a fluorescence transient from SMF-treated plants, gave a higher fluorescence yield at J–I–P phase in leaves of plants that emerged from SMF-pre-treated seeds even under saline conditions. Photosynthetic pigments, the efficiency of PSII, performance index based on absorption of light energy, photosynthesis, nitrogenase and nitrate reductase activities were also higher in plants emerged from SMF pre-treated seeds, which resulted in an improved yield of the plants even in the presence of salt stress. As a result, SMF pre-treatment ameliorates salt stress so that the plants do not have to divert their metabolic energy in detoxification of ROS produced under stress conditions. Thus SMF pre-treatment to the seeds eliminates the need for defense against abiotic salt stress. Hence magnetopriming of dry seeds can be effectively used as a pre-sowing treatment in order to mitigate abiotic-stressinduced adverse effects on different crop plants under field conditions. In conclusion, SMF may be a good tool for improving agricultural production in the future because of its moderating effect towards high temperature, drought, salinity and UV-B stress.
