Location: Subtropical Insects and Horticulture Research
Project Number: 6034-22320-006-005-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 22, 2025
End Date: Sep 21, 2026
Objective:
We will deliver a bioproduction platform that leverages a naturally occurring soil bacterium’s (Agrobacterium tumefaciens) ability to locally modify plant cells to grow into a gall that can be engineered into an on-plant bioreactor that we call a “symbiont”. This innovative approach should enable inexpensive/scalable production of biomolecules that can accumulate within, and be harvested from, the symbiont. Proof-of-concept will be provided by producing the AMP combinations that are currently showing activity against the ‘Candidatus’ Liberibacter solanacearum bacterium in on-plant potato and tomato trials and that have shown promise in citrus using potted greenhouse tree assays.
Approach:
Our team will demonstrate 1) how to produce AMP combinations in, and isolate from, Symbionts as extracts for direct injection; 2) These extracts will be used for injections in both greenhouse and field citrus trees to demonstrate effectiveness in controlling HLB disease. The deliverables will be commercializable methods of producing AMPs in a low-cost scalable method as demonstrated as a solution to citrus greening disease. The underlying research hypothesis of this study is that we can develop injectable therapeutics for treating HLB -symptomatic trees using symbiont produced AMPs and, at the same time, develop a method to invigorate rural agriculture and support nutritional and food security because they can be produced as a harvestable commodity that produces/stores desirable biomolecules allowing their use in livestock and plant health management, thus bolstering US food security and rural small farm economics, and aid in supporting a nutritionally diverse U.S. food supply. The system will be tested, at each step using previous knowledge gained for symbiont production, AMP harvest and direct tree injection, as proof of concept.