Effect of seed magneto-priming on growth, yield and Na/K ratio in wheat (Triticum aestivum L.) under salt stress

Abstract

Seeds of wheat genotypes, HD 2967 (salt sensitive) and Kharchia 65 (salt tolerant) were magneto-primed with 50 mT (2 h) static magnetic field and subjected to salinity stress (150 mM NaCl) from seedling stage to maturity. Magneto-priming caused significant increase in height, leaf area and dry weight of the plants of both the genotypes under non saline and saline conditions. Net photosynthetic rate recorded a marked increase under normal and saline conditions in both the genotypes. Greater increase in total chlorophyll content was observed under priming in leaves of HD 2967 compared to Kharchia 65 under all treatments. Total root length, average diameter and surface area of the roots increased in primed seeds with magnitude of increase being more in Kharchia 65 under salinity. The decrease in average root diameter in roots from magneto-primed seeds indicated towards finer roots developing in the primed seeds. Under salinity, the Na+/K+ ratio was less in plants from primed seeds compared to unprimed seeds irrespective of the plant parts. The sodium exclusion in primed seeds may be beneficial in imparting tolerance to wheat genotypes under stress. Increase in yield of plants from magneto-primed seeds under non saline and saline condition is an integration of stimulation in growth and tolerance to salinity at all stages of growth. The salt sensitive variety HD 2967 benefitted more than Kharchia 65 (salt tolerant) under saline conditions as magneto-priming induced tolerance and gave yield comparable to unprimed normal sown condition.