Spraying Colchicine on Flower Buds of Exacum Ritigalensis (Binara/Ginihiriya)

Abstract

Exacum ritigalensis has a high potential to be introduced as a floricultural plant to the floriculture industry of Sri Lanka. In this regard, improvements of its morphological characters through genetic modifications are important Spraying colchicine is one of the methods which can be applied to plant to alter plant morphology. This study was conducted to find the effect of spraying different colchicine concentrations on flower buds of E. ritigalensis. The flower buds at the same reproductive stage were treated with a drop (lm l) of the colchicine solutions (0, 30, 60, 90 and lZOmgL1). Treated plants kept under the green house without wetting stem and bud from other liquids. Water was applied regularly to soil. Experiment was arranged according to the Completely Randomized Design (CRD) with five replicates per each treatment. Observations on flower diameter (cm), color of the flower (deviation from natural colour; light, normal and dark), days to flowering and seeds weight per pod (g) of plants were recorded. Statistical analysis was performed with Duncan's multiple range test using SAS software (version 9.1.3) and Wilcoxon sign rank test using SPSS statistics package (version 20). Results revealed that the spraying of colchicines on flower buds did not have effect on flower diameter and days to flowering. But colchicine concentration lZOmgL'1 resulted in lighter colour of flowers compared to control but produced no seeds in pods.