This is the final report for project 18-016. A final comprehensive report is being submitted along with this summary document. The final comprehensive report contains additional project details and relates the project to previous funding by CRDF. 1. Please state project objectives and what work was done this quarter to address them: The project objective is to test transgenic ‘Duncan’ grapefruit trees for resistance to citrus greening. Infections were done by grafting onto infected rough lemon rootstocks, caged infected psyllid feeding, and natural infection outdoors. Tree symptoms were visually assessed and ‘Candidatus Liberibacter asiaticus’ bacterial titers were determined by quantitative PCR (qPCR) in collaboration with Southern Gardens. All the tests proposed were performed and have now been completed. This quarter, we performed final data analysis and began to prepare a manuscript describing the tree citrus greening disease data. The manuscript is still at an early stage, but figures are nearing completion, which is the first major step. The text will be adapted from a M.S. student Chad Vosburg’s thesis document. 2. Please state what work is anticipated for next quarter: This is the final report. However, we are still working on a manuscript to publish the tree test data. 3. Please state budget status (underspend or overspend, and why): The project remains underspent in part due to support for graduate stipends and tuition waviers from the Plant Pathology & Environmental Microbiology Department of Penn State and the Penn State Graudate School. We are reporting the project as 98% completed because we still need to submit the manuscript to a peer-reviewed journal and get it accepted for publication.