Almond Can Be Infected by Plum Pox Virus-D Isolate Penn4 and Is a Transmission-Competent Host.

Although it is currently eradicated from the United States, Plum pox virus (PPV) poses an ongoing threat to U.S. stone fruit production. Although almond (Prunus dulcis) is known to be largely resistant to PPV, there is conflicting evidence about its potential to serve as an asymptomatic reservoir host for the virus and thus serve as a potential route of entry. Here, we demonstrate that both Tuono and Texas Mission cultivars can be infected by the U.S. isolate PPV Dideron (D) Penn4 and that Tuono is a transmission-competent host, capable of serving as a source of inoculum for aphid transmission of the virus. These findings have important implications for efforts to keep PPV out of the United States and highlight the need for additional research to test the susceptibility of almond to other PPV-D isolates.

Complete genome sequence of almond luteovirus 1, a novel luteovirus infecting almond.

In this study, we report the complete genome sequence of a novel luteovirus detected in almond using high-throughput sequencing. The genome of the new luteovirus comprises 5,047 nucleotides, and its genomic organization is similar to that of the recently described nectarine stem pitting associated virus (NSPaV), with only four open reading frames, encoding replication-related proteins, the coat protein (CP), and a CP readthrough protein involved in the aphid transmission of luteovirids. Phylogenic and pairwise distance analyses showed that this virus shares 79% and 57.8% amino acid identity in the P1-P2 fusion protein and the P3-P5 protein, respectively, with the most closely related luteovirus, NSPaV, suggesting that it represents a novel species, for which the name "Almond associated luteovirus 1" is proposed. To our knowledge, this is the first report of an almond-infecting luteovirus.