Sustainable Control of the Sugarcane Smut Disease Caused by Sporisorium scitamineum Piep. Using an Essential Oil of Cymbopogon citratus

Sugarcane smut disease, caused by Sporisorium scitamineum, is one of the most damaging fungal diseases in the world. This study aims to evaluate the effect of treatment with a formulation based on Cymbopogon citratus essential oil on the incidence of S. scitamineum in sugarcane cultivation. The study was conducted under controlled conditions at the research site of the Bingerville scientific pole in Cote d'Ivoire. Some sugarcane cuttings of NCo376 variety were inoculated by dipping in a teliospores solution of 5.106 teliospores/ml. Before planting, the cuttings were cold treated in a C. citratus essential oil. Propiconazole-treated cuttings served as a reference control and untreated cuttings served as a negative control. Agronomic parameters of the cane and descriptors of smut disease were monitored for eight months to assess the health status of treated and untreated plants. Analysis of variance and comparison of means were performed using the Newman-Keuls test at 5% significance level using Statistica 7.1 software. The results showed that, the pre-treatment of cuttings with C. citratus oil had a benefic effect on the cutting’s germination, height, tillering, stem diameter, internode length, number of internodes and biomass of sugarcane plants with the doses of 500-ppm and 1000-ppm. Moreover, the incidence of smut disease was greatly reduced from the 500-ppm of C. citratus essential oil. In addition, the essential oil-based treatment had similar effects to propiconazole and much better than the untreated controls. Therefore, this pre-treatment of cuttings with C. citratus essential oil could be an alternative to the use of chemicals in the fight against sugarcane smut disease.