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

seeds to a static MF of 50 mT for 2 h helps to increase root growth, leaf

chlorophyll content, photosynthesis rate and various yield attributing traits

like number of the effective tillers, number of grains per plant and test weight

of grain which in turn result in higher grain production of wheat, and also

help the plants to alleviate the adverse effect of salinity stress (Rathod &

Anand, 2016). Magneto-priming of chickpea (Cicer arietinum) seeds has

been found to increase yield by 33% and also to effectively mitigate the

negative influences of salt stress in this crop (Thomas et al., 2013). Bilalis

et al. (2012) have reported that pulsed EMFs exposure on maize seeds for

30 and 45 mins enhance the quantity of yields. A significant increase in the

fruit yield of strawberries (Fragaria vesca) had also been described when

strawberry plantlets were treated with MF in the range of 0.096 to 0.192 mT

(Eşitken & Turan, 2004). Further, seed treatment with MF of 100 mT for 10

mins and 170 mT for 3 min has been observed to effectively increase the

growth and yielding parameters of tomato like weight fruit^–1, fruit plant^–1,

fruit yield area^–1 or fruit radius (De Souza et al., 2006).

5.2.4 EFFECTS ON ALLEVIATION OF STRESS

Abiotic stresses or environmental extremities such as salinity, water stress,

high or low temperature, UV-B, etc., are well known to decrease germination

rate, seedling vigor, nodulation, carbon, and nitrogen metabolism, growth

rate, biomass production and ultimately crop yield. Researchers are of the

opinion that the activation of pre-germinative metabolism as induced by the

priming method would instill a kind of “stress memory” within seeds (Chen

et al., 2012). As a consequence, such “stress memory” activates various

protective mechanisms within the plant if it faces any stressful conditions

during later stages of growth. Later on, the activated protective systems

help the plant to alleviate the stress effects or also make the seedlings more

tolerant to the specific kind of stress.

Pre-treatment of maize seeds with SMF 100 mT for 2 hours and 200

mT for 1 hour has been reported to help the plants to maintain the normal

growth, water status of leaf and photosynthetic rate during the water stress.

It is also noteworthy to mention that MF treatment shows reduced levels

of free radicals and antioxidant enzyme activities in the leaves of 45-days

old plants under mild and extreme water stress conditions in comparison to

control plants (Anand et al., 2012). Seed priming with physical agents like

static magnetic field has been reported to deliver compensating performance

in respect of crop growth and yielding parameters both under normal and