First record of Plum pox virus in Jordan

In Jordan, 51 commercial stone fruit tree orchards, several private gardens and four varietal collections were surveyed in different parts of the country, for virus diseases. A total of 1312 peach, plum, apricot, almond, and cheery trees were sampled and tested for the presence of Plum pox virus (PPV) by DASI-ELISA, using the universal monoclonal antibody MAB5B. Graft transmission to GF305 and mechanical inoculations to herbaceous hosts were made from symptomatic samples. PPV was identified serologically in several trees, i.e. three peaches, two plums, and two apricots. The virus was successfully graft-transmitted to GF305 and mechanically to Nicotiana occidentalis and N. benthamiana. Strain-specific monoclonal antibodies were used for identifying the virus strains, all of which were found to belong to PPV-M. No evidence was found of active PPV spread in the field, although infected trees were few and scattered, they constitute highly dangerous inoculum sources, which should be promptly eliminated.