The effects of dry stress result of poly Ethylen Glycol (PEG) on germination, the length of hypocotyle, and the length of seedlings root in two cultivars of Brassica napus L.

This research is about the reaction of two rape seed (Brassica napus L.) cultivars towarddrought on, primary vegetative period, the percentage of germination, the length ofhypocotyle and the length of seedlings root. Brassica cultivars were PF (spring type) and SLM (winter type). Dry stress was made by different concentrations of PEG. Applied treatments are as follows: Distilled water, PEG 0/1 gr/ml (pressure -2 bar), 0/14 gr/ml (pressure -4 bar), 0/19 gr/ml (pressure -8 bar), 0/23 gr/ml (pressure -12 bar). Treatments were irrigated every three days in the same conditions and after six days, related characteristics considered. The result showed that percentage of germination length of hypocotyle, the length of seedlings root in both cultivars decreased with the increase of PEG concentration and SLM cultivar in high concentration of PEG in comparison with PF had more resistance toward stress.