First report of Guignardia citricarpa in Ghana
In Ghana, symptoms of citrus black spot were detected approximately 10 years ago in a few orchards near Kade (Eastern region) but the causal agent, disease distribution and impact were not known. Surveys were carried out in 2009 in the major citrus-producing areas of Ghana (50 and 52 orchards in the Eastern and Ashanti regions, respectively), and in several markets (5 in Accra, 2 in Kade). These surveys showed that the fruit spot disease associated with the most severe losses was caused by Guignardia citricarpa (EPPO A1 List). They also showed that within 10 years the disease has spread widely across the Eastern and Ashanti regions, and that crop losses due to the disease alone or in combination with fruit flies could reach 80%. In diseased fruit, G. citricarpa and the endophyte G. mangifera often co-existed, thus complicating diagnosis when based solely on isolations. It is concluded that disease control programmes should be urgently implemented to prevent the spread of G. citricarpa, in particular to regions where new citrus orchards are being planted (i.e. Western and Brong Ahafo regions). This is the first record of G. citricarpa in Ghana, as well as in West Africa.
The situation of Guignardia citricarpa in Ghana can be described as follows: Present, first confirmed in 2009, widespread in the Eastern and Ashanti regions.
Sources
Brentu FC, Oduro KA, Offei SK, Odamtten GT, Vicent A, Peres NA, Timmer LW (2012) Crop loss, aetiology, and epidemiology of citrus black spot in Ghana. European Journal of Plant Pathology 133(3), 657-670.