The effect of seed priming on emergence and root morphological characteristics of canola at different sowing dates

Seed priming is a method which is effective in improving germination and seedling establishment under stress conditions. To investigate the effects of seed priming on emergence and morphological characteristics of root of three canola cultivars, an experiment was arranged in a randomized complete block design in split plot with three replications. Main factors including five sowing dates with an interval of ten days and three canola cultivars and priming treatments including priming with water, zinc sulfate and control as sub plots were arranged in a factorial experiment. Results showed the highest emergence rate was achieved in Okapi by zinc sulfate priming with an average increase of 32 percent in all sowing dates. The most of the fresh and dry weight of three cultivars resulted from the first sowing date, 6 September. Sowing date October 16 under the hydropriming and primed with zinc sulfate increased root length by 7 and 10 percent in the Okapi, 18 and 23 percent in Zarfam and 32 and 35 percent in Talayeh compared with their controls, respectively. Root volume of Okapi on September 26, October 6 and 16, increased respectively 38, 61 and 71 percent in hydropriming and 51, 67 and 47 percent by priming with zinc sulfate compared with their control treatments. The highest root area on 6 and 16 September in all three cultivars was achieved by priming with zinc sulfate. Despite the decrease in root diameter of delay sowing date, priming treatments could increase root diameters compared with controls in each sowing date.