Effect of Colchicine on Increasing Pollen Viability in a Curcuma Hybrid (Curcuma sparganifolia × C. parvifl ora)

Abstract

Interspecifi c crosses of Curcuma spp. often exhibit good characteristics and hybrid vigor but they are usually sterile and cannot be used as parents for further breeding. Increasing ploidy is one way of increasing pollen viability. When colchicine was applied to retarded shoots of Curcuma hybrids at concentrations of 0, 1, 3 and 5 mg.L-1 for 48, 72 and 96 hr, the survival rate dropped with increasing concentration of colchicine and exposure time. Staining with potassium iodide was used to test the pollen viability and resulted in the highest mean percentage of viable pollen being 20.53% found in the treatment group that was exposed to 3 mg.L-1 colchicine for 48 hr. Flow cytometry confi rmed that the number of chromosomes had increased, resulting in greater pollen viability.