Sugarcane Smut ( <i>Sporisorium scitamineum</i> ), a major threat to sugarcane production: designing sustainable management option for sugar and cane productivity in Ethiopia

Sugarcane smut is the most important bottleneck in sugarcane production in Ethiopia. Previous management attempts couldn't protect the crop from smut sustainably. Therefore, experiments were conducted with the objective to assess the combined effect of varietal resistance, fungicide, and Trichoderma harzianum seed cane treatments on smut, cane, and sugar yields at Metehara and Wonji, Ethiopia. Thirty-six treatments were planted in a split plot design, with three varieties as main plots and twelve seed cane treatments as subplots in three replications. Consequently, untreated NCo-334 variety demonstrated greater smut intensity (incidence and severity), followed by untreated Mex 54-245 at Wonji in plant cane. Ratoon crops prevailed similar trends of infection except that Mex 54-245 treated with Apron, Triadimefon + Native Trichoderma harzianum (NT) and NT were unable to protect smut. Moreover, NCo-334 with all treatments at ratoon showed different levels of smut intensity at Wonji. On the other hand, greater mean smut intensity prevailed at Metehara than at Wonji. Overall, up to 30.75 and 29.80%, increase in cane and sugar yield respectively, could be achieved with seedcane treatments as compared to untreated control at the two locations. In general, the results of disease intensity, sugar yield, and economic analysis demonstrated that Opera and Opera + NT could be used as seedcane treatments after verification and demonstration for end users. The better protection against smut up to ratoon crop cycle, and economic return were the main reason to consider these treatments as candidates.