LEAF EXTRACTS OF JATROPHA CURCAS, PSIDIUM GUAJAVA AND ANDROGRAPHIS PANICULATA CONTROL MICROBIAL POPULATION IN THE VASE SOLUTION OF CUT 'MOKARA RED' ORCHID FLOWER

Contamination by microbes in the vase solution causes petal wilting and discoloration of cut flowers, thus reducing vase life. Cut ‘Mokara Red’ orchid flower was used to determine the effect of leaf extracts from Jatropha curcas (J), Psidium guajava (P), and Andrographis paniculata (A) on microbial populations in the vase solution. Freshly cut ‘Mokara Red’ orchid flowers were placed in vase solutions containing leaf extracts (0, 5, 10, and 15 mg/L) + 2% sucrose (S) + 3% citric acid (C). Their effects were compared with a standard solution (STD) of 125 mg/L 8-hydroxyquinoline citrate+S+C as a positive control. Tap water (TW) was used as a negative control. The experiment was a completely randomized design with five replications. The effects of the treatments on vase life and quality of the cut flower were measured. The results indicated that flower in the vase solution containing paired combination of JASC and JPSC leaf extracts had 13-17% higher water uptake, during 10 days of treatment, compared to flower in the STD vase solution. Flower with high water uptake was associated with an extended vase life. Fungi and bacteria were not found in the paired combination of JASC and JPSC leaf extracts treated vase solution, respectively. Flower in the JPSC leaf extracts treated vase solution retained better petal colour 3 days longer than the other flower. Thus, leaf extracts of J. curcas in combination with P. guajava has the potential to minimize microbial populations in a cut flower preservative solution and extend the vase life of the flower.