Implications of Saline Water Irrigation for Linseed on Seed Germination, Seedling Survival and Growth Potential

Saline water irrigation is considered a severe threat for plants seed germination because it has highest concentration of soluble salts. This study aims to examine the effect of NaCl salt at 100 mM and 200 mM concentrations on linseed (Linum usitatissimum L.) germination, plant growth, nutrients and soluble salts uptake. The results revealed that tested four linseed genotypes showed an overall germination rate of 86-94% at 100 mM NaCl (T2) and 78-84% at 200 mM NaCl (T3) and seedling survival rate of 80-90% at T2 and 40-60% at T3. Seedling survival was related to seedling vigor and tolerance to salinity, as salt tolerant genotypes with healthy seedlings showed better survival and growth rate under salt stress conditions. The minimum relative growth rate was recorded as 68% to respective control in S-907 genotype at 100 mM NaCl while it was 38% of respective control in C-99-3-115 genotype at 200 mM NaCl stress conditions. In linseed growth, K^+/Na^+ratio proved to be a critical factor in relative growth rate and biomass production while the ability of linseed genotypes to accumulate Na+ at root level and to restrict the entry of this ion to upper parts of the plant seemed to be one of the distinct features of salt tolerant genotypes.Salt tolerant genotypes of linseed expressed a genetic vigour to combat salinity stress by restricting Na+ entry at root level and by using this trait through biotechnology, plant breeders can produce salt tolerant crops.