Occurrence and distribution of pome fruit viruses in Tunisia

Abstract

The phytosanitary status of pome fruit trees was examined in Tunisia, in surveys conducted in spring 2009 and 2010, in the main Tunisian mother blocks. A total of 248 samples were collected (111 from apple, 106 from pear and 31 from quince), and tested for the presence of Apple chlorotic leaf spot virus (ACLSV) and Apple mosaic virus (ApMV) using ELISA and RT-PCR, and for Apple stem pitting virus (ASPV) using RT-PCR. 37% of the samples were infected by at least one virus. ACLSV was the most widespread virus (34% of samples), followed by ApMV (4%). Furthermore, molecular analysis showed that 69% of the sampled trees were infected and apple was the most infected species (80%), followed by pear (75%) and quince (10%). ASPV was the most prevalent virus (46%), followed by ACLSV (39%) and ApMV (10). Mixed infections occurred in several trees, and the most common combination was ASPV+ACLSV (23%). This is the first report on the presence of viruses infecting pome fruits in Tunisia.