Analysis of the Disease Progress Curve in Sugarcane Genotypes Infected with Sporisorium scitamineum Under Greenhouse Conditions

The progression dynamics of sugarcane smut, caused by Sporisorium scitamineum, remain underexplored despite their considerable impact on sugarcane crop productivity. The comprehension of these dynamics contributes to the development of breeding strategies for selection of resistant genotypes and effective disease management. This study analyzed disease progress curves in sugarcane genotypes inoculated with S. scitamineum under controlled greenhouse conditions. Eight genotypes, selected based on Expected Difference from the Parent and classified by their Relative Area Under the Disease Progress Curve (rAUDPC) as susceptible or moderately susceptible, were evaluated for model fit using four epidemiological models (monomolecular, Gompertz, logistic, and exponential) via linear and nonlinear regression analyses. Overall, the disease progress curves showed good fit with the tested models, with the monomolecular and Gompertz standing out as the best fit. These findings are consistent with previous field-based epidemiological studies of sugarcane smut, reinforcing their applicability in greenhouse assessments.