نخستین گزارش از گونه‌های Albonectria rigidiuscula و Fusarium annulatum همراه با بیماری شانکر انجیر

The fig tree (Ficus carica L.) is of global interest due to its fresh and dried fruits. Iran is the fifth-largest producer, yielding approximately 84 thousand tons of figs annually. The world's largest rainfed fig orchards are in Estahban County, Fars Province. Given the importance of dried fruit in this region, several limiting factors have affected the production of this fruit tree. The emergence and increase of trunk and branch canker and decline is one of these factors. Some ascomycete fungal pathogens associated with these diseases have been reported, including some species in Bionectriaceae, Botryosphaeriaceae, Diaporthaceae, and Diatrypaceae families. To identify other fungal pathogens involved, fig trees with trunk and branch canker symptoms in Estahban and Marwarid Counties, Fars Province, were investigated in this study. Initial morphological identification and grouping of 12 isolates showed that these isolates were in two different groups of Fusarium-like fungi. Molecular identification of the representative isolates through polymerase chain reaction (PCR) targeting the translation elongation factor 1 alpha (tef1) gene with the primer pair EF-1H and EF-2T revealed that these isolates are ascomycete pathogens Albonectria rigidiuscula and Fusarium annulatum in the Nectriaceae family. Previous studies have identified these species as causal agents of canker in various fruit trees. Therefore, detached shoots of the ‘Sabz’ fig cultivar were inoculated with all isolates from both species. To select the most aggressive isolate for subsequent pathogenicity evaluation on fig saplings, a statistical analysis of three pathogenicity factors, including the length of upward and downward lesions, and width of lesions, was performed. These analyses revealed varying levels of aggressiveness among isolates. Pathogenicity tests on the one-year-old ‘Sabz’ fig saplings using the most aggressive isolates demonstrated that these species could induce symptoms on branches, such as sunken lesions and wood discoloration. This study represents the first global report of A. rigidiuscula and F. annulatum causing trunk and branch canker on fig trees.