1. Please state project objectives and what work was done this quarter to address them: Main objective: To determine the large-scale efficacy of trunk injection of OTC on citrus tree health, fruit quality, and yield in existing rootstock trials in three different commercial growing environments. Sub-objectives: a) test the efficacy of OTC injection in the rootstock trunk compared to injection into the scion, and b) determine whether OTC injection increases/restores root densities and if there are interactions with the rootstock. Harvests and fruit quality analyses were completed for the trial in SW Florida. Tree care was not as desired in this location as the collaborator (Duda) has ceased citrus production in this area. Overall, trees were still relative productive in this trial with an average of 102 boxes per acre. The best performing rootstock in this location in terms of production was UFR-2 (144 boxes/acre), and the worst was Swingle (46 boxes/acre). Across all rootstocks OTC injection increased yield by 21% but differences were not statistically significant. The yield for trees on US-812, UFR-2, and Swingle improved the most (28-29%) while there was little to moderate improvement for trees on UFR-4 (5%) and US-942 (14%). OTC injection increased juice quality significantly across all rootstocks.There was no significant difference between rootstock and scion injection for yield and juice quality. Wound closure was the same on scion and rootstock. However, bark cracks were longer after scion injection than after rootstock injection. There were significant differences among rootstocks for both wound closure and bark crack length. Year-2 injections were completed. This year we measured significant differences in the uptake rate between rootstock and scion injection: trees injected into the scion took OTC up significantly faster than trees injected in the rootstock. 2. Please state what work is anticipated for next quarter: We will monitor the trees and continue to collect leaf samples for CLas detection. Fibrous root density collections will be performed. 3. Please state budget status (underspend or overspend, and why):The budget is mostly as expected.