Studies on the nodal infection of red rot of sugarcane

Abstract

The reaction of 6 sugarcane varieties to red rot infection through the nodal region caused by Colletotrichum falcatum Went was studied. Cane varieties Co. 445, Co. 331, Co. 312 and Co. 1181 were found to be susceptible while Co.1070 and Co. 286 proved to be moderately resistant to nodal infection. The fungus persited in an incipient form in the nodal regions of apparently healthy stalks of sugarcane. A number of leaf - sheaths also yielded the fungus on isolation. The leaf - sheath water (the water accumulated in the cavity between the leaf-sheath and stalk) collected from the above 6 varieties of sugarcane stimulated the spore germination of the fungus. The presence of sugars viz., sucrose and laevalose, detected in the leaf sheath water by paper chromatographic analysis, is believed to be responsible for the stimulation of spore germination.