The objective of this project is to compare commercial adjuvants effects on systemic delivery of oxytetracycline (OTC) and streptomycin (Strep). Implementing this objective involves two experiments: One testing effects on delivery of OTC and one testing effects on delivery of Strep. Because the compound is expected to behave differently (based on preliminary experiments and based on recommendations of the company marketing both ingredients), we will use a different set of adjuvants for each, with some overlap. We have made three modifications to the original plan: 1.) We included injection as a positive control, because effective delivery has been reported through trunk injection. 2.) We included two experimental adjuvants in addition to all of the adjuvants recommended by AgroSource for the OTC study. 3.) We chose to implement this experiment on CLas infected trees in the field, because results using uninfected trees could be questioned on the basis that delivery might be affected by infection status. All of these changes expand, rather than reducing, the results and potential impact.
We have acquired all the adjuvants and antimicrobials materials needed and designed both experiments. We have implemented the first experiment, addressing delivery in December 2019 and have collected the materials for testing, and quantification of OTC in the samples is in process. We will use the results from the first experiment to assess experimental design for the Strep study. We expect to have complete results from the OTC study in Q2. We rate our % objective completion at 25% because we have completed approximately ½ of the objective to address OTC, which could be considered ½ of the complete objective.