Role of gibberrelic acid in influencing the phenolic and flavonoid contents in Withania somnifera (L.) Dunal plants.

摘要

In the present investigation an attempt has been made to find out the effect of GA₃ on total phenolic, flavonoid, chlorophyll and carotenoid content in plants of two varieties of Withania somnifera (i.e. cv. Poshita and cv. Jawahar20) after 45, 90 and 135 days of sowing. Seeds were soaked in 50, 75 and 100 ppm GA₃ solution for 24 hours. Data collected after 45, 90 and 135 days of sowing revealed significant increase in total phenols and flavonoids in root, stem and leaves of the GA₃ treated plants. GA₃ at 50 ppm level gave best results in terms of increasing the antioxidant potential of the plants with respect to these biochemical parameters. The roots contain more amounts of these antioxidants than stem and leaves. However, GA₃ treatments were not found effective in altering the carotenoids levels in leaves as compared to control. Total chlorophyll content was however, significantly increased when treated with 50 ppm GA₃ From the study it can be concluded that the roots of Withania somnifera are good source of antioxidant components and cv. Jawahar 20 was a better yielder of flavonoids than cv. Poshita.