Effect of Jatropha curcas, Psidium guajava and Andrographis paniculata leaf extracts on postharvest performance of cut Mokara red orchid flowers

Abstract

The effect and optimum concentration of Jatropha curcas, Psidium guajava and Andrographis paniculata single leaf extract (SLE) and double combination leaf extracts (DCLE) on postharvest performance of cut Mokara Red orchid flowers was studied. The 15 mg/L DCLE of P. guajava and A. paniculata containing floral preservative solutions had the stable pH (initial pH 3.0) compared to the pH of SLE floral preservative solutions, resulting in extended vase life of the cut flowers. Moreover, flowers in the above preservative solutionstreated flowers retained better petal colour than the colour in the other treated flowers. Thus, 15 mg/L DCLE-Pg+Ap was used in subsequent experiments to evaluate the long vase life of cut flowers based on higher rates of preservative solutions uptake. The all-preservative solutions contained two groups of bacteriaand three fungi. The 15 mg/L DCLE-Pg+Ap had lower bacterial populations compared to the 15 mg/L DCLE-Jc+Ap, except in fungal growth. Therefore, DCLE-Pg+Ap had the potential as a natural preservative solutions to extend the 3 days more vase life of orchid flowers compared to the control containing 8-HQC (8-hydroxyquinoline citrate). Future research needs to examine which microbes are responsible for xylem blockage and their effects on the postharvest performance of cut flowers