Evaluation of sesame cultivars for resistance to Cercospora leaf spot

Abstract

White leaf spot and angular leaf spot caused by Cercospora sesami and C. sesamicola respectively were monitored in plots of 16 sesame accessions at Siaya Farmers' Training Centre and Kibwezi Dryland Research Station, Kenya to determine the relative susceptibility of these accessions. Increase in percentage diseased leaves and percentage defoliation fitted the Gompertz model more closely than the logistic model. Rates of disease increase in infected leaves and defoliation as well as areas under disease progress curves (AUDPC) varied among the 16 accessions. Accessions with large AUDPC generally had faster rates of disease progress, although this is not always the case. The most susceptible accessions to both diseases were SPS 071 and SIK 134. Accession SIK 031 and SPS 045 exhibited the latest susceptibility to white leaf spot and angular leave spot, respectively and are suggested as future standards for comparing reaction of other genotypes to Cercospora leaf disease of sesame