Abstract
Spinach seeds show low germination percentage and speed due to pericarp imposed physical and chemical hindrance; the
problem is further aggravated under saline conditions. To assess seed vigor and repress salinity induced lipid peroxidation, seeds of spinach cultivar ‘Desi Palak’ were subjected to various treatments viz., soaking in distilled water (for 4 h), washing
of seeds with bleach i.e. sodium hypochlorite (for 10 min, 50% of commercial grade), seed priming (30 h) using distilled
water i.e. hydropriming (with or without soaking), kinetin (25 ppm, after bleach and soaking; hereafter mentioned as kinetin
only for simplicity) or Indole–3–Acetic Acid (IAA 100 ppm, after bleach and soaking; hereafter mentioned as IAA only for
simplicity). The effect of seed treatments on seed vigor and salinity tolerance was evaluated through germination test (at 0, 50, 100, 150, and 200 mM NaCl induced salinity) and emergence test (at 0 and 200 mM NaCl induced salinity). Seed
priming using IAA showed better final germination and emergence percentage, germination index, germination and
emergence energy, seedling biomass, chlorophyll contents and vigor index than control and other seed treatments. All
parameters were negatively affected by salinity but were altered to significantly lesser extent in seeds primed with distilled
water or IAA, especially IAA at higher (200 mM) salinity levels. Bleach and soaking treatments seemed to soften the
pericarp as evident by enhanced germination/emergence, germination energy and index, while reducing mean
germination/emergence time. Further seed enhancement and increased biomass production in IAA or hydro- primed seeds
(after bleach and soaking) can be attributed to reduced lipid peroxidation as evidenced by low MDA contents in seeds primed
with IAA and distilled water, particularly under saline conditions