In November 2006, orange fruits showing black spot symptoms were brought to the rural plant clinic at Katine market near Soroti, run by the local organization SOCADIDO. Small 4-5 mm lesions with light centres, surrounded by a darker red to purple rim were observed on the surface of the fruit. Within the lesions, numerous dark black fruiting bodies were seen, typical of Guignardia citricarpa infection. This fungus is a damaging pathogen on Citrus species and causes black spots on leaves and fruits. Fruit quality is affected by the disease and blemishes reduce the aesthetic value and saleability of the fruit. Observations on morphological and cultural characteristics confirmed the identity of the pathogen. This is the first confirmed record of G. citricarpa from Uganda.
Reeder, R.; Kelly, P.L.; Harling, R. First confirmed report of citrus black spot caused by Guignardia citricarpa on sweet oranges (Citrus sinensis) in Uganda. Plant Pathology (2008) 58 (2) 399-399. [DOI: 10.1111/j.1365-3059.2008.01966.x]