Effect of salinity stress on α-amylase activity, cell membrane leakage and seedling growth of canola cultivars

In this experiment, the response of canola cultivars to salnity stress in germination stage was evaluated using a factorial experiment with four replications in completely randomized design. Six canola cultivars (Fornex, Alice, Orient, Consoul, Okamer and Okapi) were subjected to four salinity levels (0, 40, 80 and 120 mMol NaCl) under room, greenhouse, field? Salinity reduced the percentage of seed germination, seedling vigor index, α-amylase activity and seedling fresh weight, but it increased the mean germination time, malondialdehyde concentration, and cell membrane leakage. At the highest salinity level, Orient and Fornex cultivars had the highest germination percentage (84% and 80%), α-amylase activity (9.3 nmol seed-1 min-2 and 9.4 nmol seed-1 min-2) and seedling fresh weight (0.95 mg and 0.70 gr) compared to other cultivars. The electrical leakage of the seedling was lowest in the latter cultivars. Results showed a positive correlation of canola seedling weight with α amylase activity but negative correlations with the malondialdehyde concentration and cell membrane leakage. Salinity stress increased cell membrane damage and decreased α amylase activity, canola seed germination and seedling growth. Results indicated that under salt stress condition, Okamer and Okapi was sensitive canola cultivars compare with other cultivars.