LOSS OF RESISTANCE IN HSF-240 AGAINST WHIP SMUT OF SUGARCANE OVER CONSECUTIVE RATOONS

Abstract

HSF-240, one of the elite sugarcane varieties, was observed for its reaction with sugarcane smut over three consecutive years under natural conditions. The study includes plant crop, first year ratoon and second year ratoon crops. The data revealed that in plant crop only 4.25 % stools were infected with smut and crop proved to be resistant during that year. In first year ratoon 18.39 % stools were infected with the disease and crop stood tolerant against the disease. However in second year ratoon the disease infected up to 38.19 % of stools rendering the crop severely susceptible to this disease. This suggests a swift replacement of HSF240 with new and promising varieties, dejection of this variety in future as a plant crop as well as a ban on keeping ratoon of this variety.