Inoculation of Curvularia eragrostidis in yam plants (Dioscorea alata) cv. São Tomé

ABSTRACT The aim of this study was to select the method of C. eragrostidis inoculation in yam seedlings (Dioscorea alata) cv. São Tomé to determine the infection and the latency period. The isolate of C. eragrostidis was obtained from yam leaves showing symptoms of the disease. Plants aged 45 days old, cultivated in a greenhouse, were inoculated with the pathogen, as follows: T1 – Spore suspension (1x10 conidia mL-1); T2 – Colonial disks of 10mm fixed with adhesive tape (two on the abaxial surface and one on the adaxial surface); T3 - Brushing of spores; T4 - Cotton soaked in the inoculum suspension; T5 - Control (plants sprayed with sterile distilled water). After 72h of inoculation, the disease incidence was daily evaluated and the severity was assessed on the 15th day. The obtained results revealed that the spore suspension spraying method was more efficient for C. eragrostidis inoculation in yam seedlings, causing the first symptoms to appear from the third day after inoculation.