Fig Rust Caused by Cerotelium fici: Past, Present and Future

Fig rust is one of the serious fungal diseases caused by Cerotelium fici which causes great loss to the overall growth and yield of the plant. This disease is generally characterized by pale reddish-brown to reddish-brown angular leaf spots, typically found on the adaxial surfaces of the leaves, whereas the corresponding abaxial surface of the same leaves was covered with a lot of orange rust pustules. With the progression of this rust disease, angular spots fused to form necrotic patches whereas, leaf edges curled upward. Premature abscission of leaves takes place, leaving bare branches and unripe fruits. This disease showed its global distribution in tropical and subtropical areas, however, the highest distribution was found in the African continent (18 countries) followed by Asia (14 countries), North & South America (10 countries each), Europe (8 countries) and 7 countries in the Oceanian continent. Apart from the rust pathogen Cerotelium fici, the Phakospora nishidana was also reported to cause fig rust which has created confusion on the identity of C. fici as a fig rust pathogen. This suggests a need to re-examine all specimens of fig rust at the global scale, based on morphological and modern DNA-based methods so that the taxonomic ambiguities on fig rust pathogens can be resolved and suitable control methods can be implemented to avoid serious crop and yield loss.

Automated summary

Fig rust, caused by Cerotelium fici, is a serious fungal disease that significantly affects the growth and yield of plants. Its symptoms include reddish-brown angular leaf spots and orange rust pustules on the abaxial leaf surface. As the disease progresses, the spots fuse, causing necrotic patches and curling of leaf edges, leading to premature leaf abscission. This disease has a global distribution, with the highest occurrence in Africa, followed by Asia, North & South America, Europe, and Oceania. Apart from C. fici, another pathogen called Phakospora nishidana has been reported to cause fig rust, creating confusion about the identity of the pathogen. Therefore, re-examination of fig rust specimens using morphological and DNA-based methods is necessary for taxonomic clarification and implementation of effective control measures to prevent crop and yield losses.