Marssonina Blotch Research Articles

In the survey from 1992 to 2000, twenty-eight parasitic diseases were observed in major apple producing areas in Korea. The predominant apple diseases were white rot (Botryosphaeria dothidea), Marssonina blotch (Marssonina mali), Valsa canker (Valsa ceratosperma), Alternaria leaf spot (Alternaria mali), and bitter rot (Collectotrichum gloeosporioides and C. acutatum). Apple scab that reappeared in 1990 after disappearance for 15 years was disappeared again since 1997. A viroid disease (caused by apple scar skin viroid) was newly found in this survey. The five diseases, fire blight (Erwinia amylovora), black rot (Botryosphaeria obtusa), scab (Cladosporium carpophilum), Monochaetia twig blight (Monochaetia sp.), and brown leaf spot (Hendersonia mali), which had once described in 1928 but no further reports on their occurrence, were not found in this survey. However, blossom blight (Monilinia mali), brown rot (Monilinia fructigena), and pink rot (Trichothecium roseum), which did not occur on apple after mid 1970s, were found in this survey.