Suppression of Sugarcane Red Rot Disease through Its Rhizospheric Mycoflora

Abstract

Red rot disease of sugarcane is so devastating in nature that it has been referred to as “cancer of sugarcane”. The sugar industry in India suffered losses more than 500 million US dollars every year due to red rot. So, there is a need to look over the management and control of the disease. Biological control method is an alternative method of chemical pesticides which are an innovative, cost effective and eco-friendly approach. Soil samples were collected from sugarcane rhizosphere of four different varieties viz., CoPk 05191 and CoLk 94184 (resistant to red rot) and CoJ 64 and Co 1148 (susceptible to red rot) planted at ICAR-Indian Institute of Sugarcane Research, Lucknow experimental farm. The samples were subjected for the isolation of rhizospheric mycoflora on Potato Dextrose Agar media and antagonistic activities of the isolates were tested against red rot pathogens (Cf 07, Cf 08 and Cf 09). Isolates showing more than 50 % inhibition with all the three pathotypes (Cf 07, Cf 08 and Cf 09) were selected for further study. Among the twelve selected isolates used for field experiment for the management of red rot, isolate T16 was found to be highly effective. The suppression of red rot offered by rhizospheric isolates is probably due to induced systemic resistance in sugarcane plants or by the enzymatic action of metabolites produced by the rhizospheric mycoflora. The different levels of red rot infected seed cane viz., 5%, 10%, 15%, 20%, 25%, 30%, 35% and 40% were treated with MHAT and planted along with healthy seed canes, infected seed canes, as a control to work out the losses caused by different level of red rot seed infection. The result revealed that a yield loss was recorded with the infected seed. The losses were directly proportionate with the level of red rot infected seed.