Effect of hydro-priming on physiological and biochemical changes of deteriorated seeds of canola (Brassica napus L.)

This research was conducted to evaluate the effects of priming on physiological and biochemical deterioration of canola seeds. A factorial experiment based on a CRD with three replicates was performed in 2012. Treatments were combinations of five levels of seed ageing (0, 48, 72, 96 and 144 hours) and three levels of hydro-priming (0, 5 and 10 hours). Canola seeds were kept at temperature of 43°C and relative humidity of 100% to create seed aging. The results of physiological changes of seeds indicated that with an increase in ageing levels, characteristics such as germination percentage, rate, uniformity, and seed reserve utilization rate, seed reserve use efficiency decreased more than, primed seeds. At all levels of ageing, primed seeds reached to 50% germination earlier than the control. In the case of biochemical changes which were consisted of lipid peroxidation rate, activity rate of superoxide dismutase, peroxidase and catalase enzymes and electrical conductivity (EC) , results indicated that with an increase in ageing levels, lipid peroxidation increased, while the activity of superoxide dismutase, peroxidase, catalase enzymes decreased. However, , the rate of this increase and decrease was less in primed seeds. In addition, at all levels of seed ageing, less cytoplasmic soluble matter moved out of plasma membrane in primed seeds compared to the control. As a whole, we can conclude that hydro-priming resulted in reduction of lipid peroxidation, improvement of deteriorated seeds , and as consequence, the emergence strength of canola seed increases.