Impact of Foliar Application with Salicylic Acid on Biochemical Characters of Canola Plants under Cold Stress Condition

Abstract

In this study the effect of foliar application of salicylic acid on the chlorophyll content, antioxidant enzymes activity, and the content of solute protein and proline were investigated in two canola varieties (Brassica napus L., cv ‘RGS’ and ‘Licord’) leaves during 0, 24, and 48 hours after salicylic acid treatment. The results showed that the content of total chlorophyll was decreased in ‘RGS’ cultivar during the experiment and this process was related with increasing of salicylic acid concentration. The activity of superoxide dismutase, peroxidase, and also lipid peroxidation were increased significantly after 48 hours compared with the first day. The results of catalase activity showed that, this trait was decreased 24 hours after salicylic acid treatment and this decrease was related with salicylic concentration. The content of protein in both cultivars slightly changed and plants treated with salicylic acid had more protein content, by contrast proline was greatly affected by salicylic acid treatment and its content was the highest 24 hours after treatment. According to the present findings the application of salicylic acid has useful effects on the biochemical traits of Brassica napus cultivars. Therefore it may be effective for the improvement of plant growth in cold regions.