1. The goal of this project is to protect citrus from Candidatus Liberibacter asiaticus by inducing the phloem to produce anchored, single-chain antibodies that will bind and immobilize the bacteria, allowing the plant to destroy them by natural defense mechanisms. Anchoring is accomplished by expressing the antibodies as extensions of native, phloem-specific sieve element occlusion (SEO) proteins. By the end of the first quarter of the grant period we produced over 30 transgenic Carrizo lines. We selected 8 lines for further analysis: 3 untransformed controls transformed without the binding proteins and 5 transformed lines with varying degrees of construct expression. On June 13, 2023, the plants were sent (with a USDA interstate transport permit) to the Amit Levy lab at the Citrus Research and Education Center at the University of Florida. 2. The Levy lab is now continuing to grow the plants and in the next month will expose them to Diaphorina citri carrying CLas.We also began the second phase of the program, to test additional antibody constructs (although this phase cannot be completed in the 1-year timeline). One objective is to use different phloem-specific promoters to increase the number of anchored antibodies in the phloem. A second strategy is to create dual antibodies, a strategy that has been shown to dramatically suppress bacterial growth. 3. The budget status is as anticipated with funds neither underspent nor overspent. 4. Commercialization products: None were anticipated for this grant, although it may be possible to commercialize the transformed Carrizo citrus as rootstocks if they are sufficiently protected by our strategy.