Effects of Seaweed on The Growth Parameters, Total Phenolic and Antioxidant Substrance Contents of Echinacea purpurea L. Under Salt Stress

This study was carried out to determine the effects of different salt sources (control, NaCl, KCl and CaCl2) as well as seaweed (Ascophyllum nodosum) extract applications (control, 2, 4 and 6 ml/l) on total phenolic, antioxidant contents and growth parameters of Echinacea (Echinaceae purpurea L.). The factorial experiment based on Completely Randomized Design established in growth chamber conditions with four replicates. Different parameters including root length, shoot length, root and shoot fresh weight, root and shoot dry weight, total antioxidant and total phenolic contents were investigated. Results showed that salt stress decreased plant growth parameters while contents of total antioxidant and phenolic substances increased compared with control treatment. Using seaweed inhibited the negative effects of salt stress and all the measured parameters were positively increased. The highest values obtained by using 6 cc/l seaweed. On the other hand, using of seaweed had significant effect (P<0.05) on total phenolic contents wh？le its effect on total antioxidant substance was not significant. The highest and least amounts of phenolic content (425.7 mg/100g and 385.4 mg/100g) observed by using 6 cc/l seaweed and control treatments respectively. Also, total antioxidant content was found between 503.2-557.5 mg/g