Phytochemical-growth Responses of Lemon balm (Melissa officinalis L.) to Gibberellic Acid and Benzyladenine under Different Nutritional Conditions

The present study aimed to assess the effects of gibberellic acid and benzyladenine on growth and some phytochemical characteristics of Melissa officinalis L. under different nutritional conditions in the hydroponic culture system. The experiment was conducted in a factorial split plot based on a completely randomized design with three replications. The main plot included nutrient solution type (Arnon Hoagland, Shi et al, and He et al that were named ۱ to ۳ throughout the text, respectively type ۱, type ۲, and type ۳) and the subplot included the factorial combination of gibberellic acid (۰ and ۱۰۰ ppm) and benzyladenine (۰, ۵۰ and ۱۰۰ ppm) as foliar spraying. The results showed that the effects of nutrient solution type on different plant growth traits, chlorophyll contents, antioxidant capacity and plant essential oil content were significant. Furthermore, different traits of the plant were affected by benzyl adenine (BA) solution spraying. The highest amounts of chlorophylls a (۱.۰۷ mg/g FW) and b (۰.۳۳ mg/g FW) and carotenoids were observed in plants treated with ۵۰ ppm BA solution. The highest amounts of phenolic compounds (۴۸.۱۳ mg/g DW) and antioxidant capacity (۱۵۴.۶۲ mg Ascorbic acid g-۱ DW) were observed at ۱۰۰ ppm BA. The use of gibberellic acid (GA۳) led to significant increases in plant height, stem diameter, internode length, shoot dry weight, chlorophylls a and b contents and plant essential oil content. However, a significant reduction in volume and dry weight of roots, and total phenol content was observed in response to GA۳ treatment. BA increased the content of phenolic compounds and the antioxidant capacity of the plants.

کلیدواژه ها:

antioxidant capacity ، essential oil ، Nutrient solution ، total phenol