First report of diplocarpon mali, the perfect state of apple blotch fungus marssonina coronaria from India

Apple blotch caused by Marssonina coronaria is widespread in North Western Himalayas and is well known for causing economic losses to the apple growers since it was first reported from Himachal Pradesh in 1994 (Sharma, 1999). The disease is becoming a major bottleneck in successful cultivation of apple in the state. In the study, apothecia with asci and ascospores (sexual fruiting structures) produced on overwintered diseased leaves of apple were recorded, which are sources of the inoculum. The fungus primarily infects apple leaves, and conidia formed in acervuli causes infection of the leaves and fruits during the growing season. The presence of apothecia with asci and ascospores is the perfect state of the causal fungus of blotch, Marssonina coronaria, is first time being reported from India. The study will lead to an understanding about overwintering stage, variability in population and infection process of the fungus.