Higher Biomass and Biochemical Compounds of Stevia rebaudiana Through Exogenous Gibberellic Acid (GA) And Kinetin (KN) hormones Treatments

Hormones are chemical messengers that regulate various physiological processes in plants. Stevia growth is affected by them, so this study investigated how gibberellic acid (GA) and kinetin (KN) affect it.  Two RCBD experiments were conducted in ۲۰۱۶ in Shirvan, Iran, to study gibberellic acid (GA) and kinetin (KN) hormones. First experiment included the following GA treatments: ۱. control (no GA) ۲. ۱۰۰ ppm ۳. ۲۰۰ ppm ۴. ۳۰۰ ppm (PPM). In the second experiment, KN was included in the treatments: ۱. control (no KN) ۲.  ۲۰ ppm ۳.  ۴۰ ppm ۴. ۶۰ ppm. At all concentrations of KN and GA, plant height, leaf number, leaf dry matter, and biomass significantly enhanced while yield index decreased. Additionally, although GA application decreased non-reducing sugars (TSSN) and total soluble sugars (TSS), KN at ۴۰ and ۶۰ ppm increased TSS. In contrast to KN treatments, GA treatments improved total stevia glycosides (TSGs). Furthermore, FLV was not affected by GA, but plants treated with KN ۶۰(KN at ۶۰) ppm had the highest FLV. All GA concentrations induced more CHL b than control. Additionally, it boosted N, P, and K, however, only KN at ۴۰ and ۶۰ ppm increased N and K. Overall, the positive effects of both hormones are dose-dependent; while KN treatment was ineffective in terms of TSG productivity, GA treatment was beneficial.

کلیدواژه ها:

Growth parameters ، glycosides ، Non-reducing sugars ، Total soluble sugars