Sugarcane (Saccharum spp.) is an important commercial crop, cultivated across the world. Smut disease is one of the major diseases of sugarcane. Severe smut infection affects the sugar recovery as well as yield loss ranging from 10 to70 %. The present study was based on the evaluation of seventy five sugarcane genotypes against smut disease by following seed sett inoculation technique under field condition to screen out the newer sources of resistance as well as susceptible for the development of the smut resistant varieties. Apart from the genotypic evaluation, cultural and morphological variability in sugarcane smut (caused by Sporisorium scitamineum) was also studied to define suitable management strategies. Out of seventy five genotypes screened against the smut disease, thirty eight genotypes viz.,LG 12201, LG 13001, LG 13002, LG 13009, LG 15169, LG 15016, LG 15026, LG 15166, LG 15185, LG 15196, LG 15245, LG 15256, LG 15259, LG 15262, LG15265, LG 15267, LG 16067, LG 16070, LG 16098, LG 16138, LG 16140, LG 16169, LG 16170, LG 16178, LG 16181, LG 16294, LG 17127, LG 17137, LG 17156, CoLk 14201, Co 14034, CoPb 14185, Co 15025, Co 16030, CoPant 16222, CoJ 64, CoLk 7701, Co 7717 and Co 419were rated as resistant (R), fifteen genotypes were found moderately resistant (MR),twelve genotypes were rated as moderately susceptible (MS),six genotypes were rated as susceptible (S) and four genotypes namely LG 17212, LG 17214,LG 17238and CoLk 7701 were rated as highly susceptible (HS). Existence of variability was noticed in the different smut samples collected from different sugarcane varieties/genotypes. Out of the ten isolates tested for cultural and morphological capabilities, each isolate differed strikingly irrespective of the host from where isolated. Isolate A-6 (host genotype LG 17288) of smut was rated as the fastest growing isolate under light condition, attaining 1.2 cm, 2.7 cm, 3.6 cm, 4.3 cm and 4.5 cm radial growth at 24h, 48h, 72h, 96h and 120h, respectively followed by isolate A-7. Whereas under dark condition, A-1 (host genotype LG 17151) isolate of Sporisorium scitamineum was rated as fastest growing isolate, attaining 1.7 cm, 3.1 cm, 4.3 cm and 4.5 cm radial growth at 24h, 48h, 72h and 96h time intervals respectively. In-vitro study of two different temperature (25ºC and 35ºC) revealed that A-7 isolate as fastest growing isolate with 1.2 cm, 2.0 cm, 2.8 cm, 3.6 cm, 4.3 cm and 4.5 cm at 25ºC and 0.8 cm, 1.4 cm, 2.3 cm, 3.4 cm, 3.9 cm, and 4.5 cm at 35ºC in 24h, 48h, 72h, 96h, 120h and 144h, respectively. A-5 was rated as the slowest growing isolate in both the temperatures. Maximum spore length of 1.58 μm was recorded with A-1 isolate followed by 1.41μmwith A-7 whereas maximum spore width of 0.45 μm was recorded with two isolates A-1 and A-7 followed by 0.44 μm with A-3 isolate.

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