First report of Alternaria brown spot of citrus in Spain
In 1998, a new disease of Fortune mandarin trees (Citrus reticulata) was observed in the Province of Valencia, Spain. Symptoms were typical of those caused by Alternaria brown spot of citrus (EPPO Alert List). Young leaves showed brown necrotic and irregular blighted areas with characteristic yellow halos. On fruits, symptoms included light brown, slightly depressed spots to circular and dark brown areas on the external surface. Necrotic lesions on leaves had a tendency to follow the veins. Infected young fruits and leaves often fell and mature fruits were unmarketable because of the lesions, resulting in important economic losses. It is noted that Fortune mandarin is one of the most important late-maturing cultivars grown in Spain. The pathogen was isolated and identified as Alternaria alternatata on the basis of conidial morphology. Koch’s postulates were fulfilled. In 1999, the disease was also found in other citrus-growing areas on Fortune and Nova mandarins, and on Minneola tangelos. The situation of Alternaria brown spot in Spain can be described as follows: Present: found in several citrus-growing areas.
Sources
Vicent, A.; Armengol, J.; Sales, R.; García-Jiménez, J. (2000) First report of Alternaria brown spot of citrus in Spain.
Plant Disease, 84(9), p 1044.