Colletotrichum coccodes has been observed in many potato growing areas in Tasmania. In many instances, the disease was suspected to cause premature senescence of potato crops. Previous attempts to demonstrate the premature senescence of potato plants due to C. Coccodes infection in field trials have not been successful. This study conducted two field trials to have more contol over purity of pathogen isolates and soil and tuber hygiene. Two pot trials in a semi-controlled environment with sterilised soil mix and sterile mini tubers have been used.