Olea europaea geminivirus is present in a germplasm repository and in California and Texas olive (Olea europaea L.) groves

Olea europaea geminivirus (OEGV) from olive accessions in Italy was characterized recently. OEGV was also detected during routine high-throughput sequencing screening of olive (cv. Leccino) material, and its complete bipartite genome segments were sequenced and shown to be 100% identical to those of the isolate from Italy. Using two pairs of newly designed primers targeting the AV1 and BV1 genes, OEGV was detected in randomly sampled olive trees from the U.S. Department of Agriculture National Clonal Germplasm Repository (USDA-NCGR) (21.4% or 6/28), commercial and residential settings in California (47.6% or 10/21), and an orchard in Texas (60% or 30/50). The cuttings for the USDA-NCGR-positive trees originated from the former Serbia and Montenegro, Spain, Italy, and Greece. Comparative analysis of the directly sequenced gene fragments from randomly selected samples showed that OEGV isolates from the different sources were 100% identical to each other. The results indicate that OEGV spread was likely facilitated by inadvertent movement of contaminated olive germplasm.