1. Please state project objectives and what work was done this quarter to address them:Objectives of this project are to determine the phytotoxicity of OTC and other potential partner antibiotics 1) by a citrus leaf assay in the lab (completed), 2) by a greenhouse assay in seedling trees (completed), and 3) to compare OTC with other antibiotics’ efficacy against CLas on mature trees in the grove (in progress). This quarter (Q3), we completed all injections on mature trees in the field, which corresponds to objective 3. All phenotypic tree measurements were taken, such as trunk diameter, canopy area, and height of each tree. We also recorded the visual parameters of citrus diseases that were present, which included HLB ratings, canker ratings, canopy color, and canopy density. Flower and new shoot formation percentages per tree were tracked to determine later if the treatment was potentially influencing/altering these parameters.We tracked all the points of injections (injection hole), one by one, and found no phytotoxicity (in terms of oozing or cracking) as of now. In general, no phytotoxicity was found on the last visit to the trial (dated 8.13.2024). Leaf samples were taken (one month after injection) and will be processed for CLas titers to compare with time zero. We will continue to sample other time points.Greenhouse phytotoxicity data (objective 2), collected during Q1 and Q2, were presented at the American Phytopathological Society’s annual Plant Health conference in Memphis, Tennessee, in July 2024. Per CRDF’s advisory request, we included additional treatment in our ongoing field trial. On August 12, we injected treatment consisting of kasugamycin +OTC (1/2 dose each; 5500 ppm) mixed together in the same FlexInjec injector (2 FlexInject per tree; 50 ml per FlexInject), as well as kasugamycin alone (1/2 dose; 5500 ppm), and OTC alone (1/2 dose; 5500 ppm) into mature Hamlin trees at the SWFREC trial site. 2. Please state what work is anticipated for next quarter:We will continue to sample leaves for CLas titers and process them to determine if a particular treatment significantly reduces CLas (using qPCR). Phytotoxicity will continue to be tracked every week. Visual and disease ratings, as well as canker incidence, will be tracked on a monthly basis. Flowers and shoots will also be counted together, along with the visual ratings. 3. Please state budget status (underspend or overspend, and why): We are paying the salary of one of the students who is working 60% on this project. The project is underspending as of now, but we anticipate being back on track soon. The reason that we are currently under budget is that a few of the most expensive antibiotics involved in the trial did not need to be purchased initially, as we had them on our hands to start. In the next couple of months, we will buy more of these antibiotics and use these funds.