Application of surfactant-modified clinoptilolite in peat substrate on the growth of Orthosiphon stamineus

Abstract

This study covers the application of surfactant-modified clinoptilolite (SMC) in peat substrate on the growth of Orthosiphon stamineus. SMC added in peat substrate may increase nutrient availability to O. stamineus by controlling anionic nutrients (phosphate and nitrate) leach to the environment. The modification of clinoptilolite (Cli) by using hexadecyltrimethyl ammonium surfactant alters the surface charge of Cli from negative to positive which is likely to attract anions when applied in the substrates. In leachate study, there was a higher amount of phosphate− and nitrate released (19.67 and 139.00 mg/L, respectively) by the commercial propagating substrate (PS) in the first day of the experiment. However, the application of Cli and SMC in peat substrate significantly reduced the concentrations of both nutrients, especially when 20% of the SMC was added in the peat substrates. There were significant differences in the growth parameters of O. stamineus, particularly those grown in 10% Cli-amended peat substrate. Results of leachate and plant growth studies indicate that Peat + 20% SMC could be a potential substrate to replace the commercial PS as it reduces the release of phosphate and nitrate, at the same time allows maximum uptake of nitrogen and phosphorus, which promotes the growth and development of O. stamineus.