Pertumbuhan, Kadar Saponin dan Nitrogen Jaringan Tanaman Daun Sendok (Plantago major L.) pada Pemberian Asam Giberelat (GA3)

The aims of this research were to study application effect on growth, saponin content and tissue nitrogen of common plantain (Plantago major L.). P. major was one of plant which has potency as a medicinal plant. The addition of GA3 exogenous to the plant would caused GA3 binding with receptor protein in the plasma membrane region, which caused specific gene activation, so that specific RNA molecule formed, and would triggered one or more enzyme forming which regulate plant growth and influence protein synthesis also plant secondary metabolite production. Data elicited by completely randomized design (CRD) with single factor (GA3 application). The application of GA3 was done once a week for two months, with following concentrations: 0 ppm, 25 ppm, 50 ppm, 75 ppm and 100 ppm, each treatment with five replications. The measurement of leaves width, dry weight, saponin content and nitrogen tissue were done after harvest. Data obtained were analyzed by using analysis of variance (ANOVA), and followed by DMRT 5% confidence level. The result showed that GA3 application giving significant effect to dry weight and saponin content; but was not give significant effect to leaves width and tissue nitrogen content. The highest GA3 concentration for increased leaves width was 50 ppm. The highest dry weight and saponin content was on 75 ppm GA3 application, whereas for the highest tissue nitrogen was on 25 ppm GA3 treatment. Keywords: gibberellic acid, Plantago major, growth, saponin, tissue nitrogen