Harper, Scott J.


Publications
4

Putting ‘X’ into Context: The Diversity of ‘Candidatus Phytoplasma pruni’ Strains Associated with the Induction of X-Disease

Citation
Molnar et al. (2024). Plant Disease 108 (9)
Names
Ca. Phytoplasma pruni
Abstract
Recurrent epiphytotics of X-disease, caused by ‘Candidatus Phytoplasma pruni,’ have inflicted significant losses on commercial cherry and peach production across North America in the last century. During this period, there have been multiple studies reporting different disease phenotypes and, more recently, identifying different strains through sequencing core genes, but the symptoms have not, to date, been linked with genotype. Therefore, in this study we collected and assessed differing disea

Physiological and Transcriptomic Analysis of ‘Candidatus Phytoplasma pruni’ Infection in Prunus persica

Citation
Wright et al. (2023). PhytoFrontiers™ 3 (2)
Names
Ca. Phytoplasma pruni
Abstract
‘ Candidatus Phytoplasma pruni’ is the causative agent of X-disease on peach ( Prunus persica) trees. Infected trees exhibit premature yellowing, leaf necrosis causing a shot-hole appearance, limb dieback, and eventual death. How pathogen infection leads to these symptoms is unknown. This study undertook a modern characterization of the disease by assessing the physiological and transcriptomic consequences of phytoplasma infection. Phytoplasma titer was high in the symptomatic tissues and undet

Recovery Plan for X-Disease in Stone Fruit Caused by ‘Candidatus Phytoplasma pruni’

Citation
Harper et al. (2023). Plant Health Progress
Names
Ca. Phytoplasma pruni
Abstract
Stone fruits are a multibillion-dollar industry for the United States and Canada, one that has repeatedly suffered significant economic losses due to outbreaks of the X-disease phytoplasma (‘ Candidatus Phytoplasma pruni’) over the last century. Orchards and entire production areas have been abandoned, with corresponding losses to growers, fruit packers, and consumers. The most recent outbreak, in the U.S. Pacific Northwest, resulted in an estimated $65 million (USD) loss in revenue between 201

Draft Genome Sequence of a Washington Isolate of “ Candidatus Phytoplasma pruni”

Citation
Wright, Harper (2022). Microbiology Resource Announcements 11 (12)
Names
Ca. Phytoplasma pruni
Abstract
Illumina sequencing of a Prunus avium tree with X-disease symptoms was performed to obtain a draft genome of “ Candidatus Phytoplasma pruni.” The genome consists of 14 contigs covering 588,767 bp. This is the first metagenome to be sequenced from the current X-disease epidemic in stone fruit in the Pacific Northwest.