Location: Subtropical Insects and Horticulture Research
Project Number: 6034-22320-007-026-I
Project Type: Interagency Reimbursable Agreement
Start Date: Sep 15, 2025
End Date: Sep 14, 2028
Objective:
1. Develop a commercially viable method of Symbiont delivery and maintenance.
i. Compare bacteria x plant interactions and adapting an USDA ARS developed Agrobacterium DNA delivery method (GAANTRY system).
ii. Develop Symbiont inoculation/containment devices for economic and effective commercial deployment of Symbionts: collaborative research involving faculty/students at the IRSC Biology program and Advanced Manufacturing Hub and other grant PI/co-PIs. The IRSC manufacturing hub has ability to produce prototype mechanical delivery devices using standard industrial methods (3D-printing, milling, CNC machining, etc.).
i. Evaluate direct DNA delivery for Symbiont production: Experimental strategies have already been developed for this objective.
2. Evaluate produced biomolecule residual in harvested fruit. Classical horticultural and molecular studies will be used to develop Symbiont systems that does not have a residual, or has acceptable residual, of Symbiont produced biomolecules in the harvested fruit.
3. Monitor impact of Symbionts on fruit drop/fruit quality in multiple citrus varieties.
4. Economic analysis of Symbiont approach: Cost vs. improve fruit yield and quality.
5. Identify genes that encode or induce natural plant defenses or antimicrobial molecules that can be produced in symbionts to protect citrus from HLB.
Approach:
Background of the PD and co-investigators includes plant molecular biology, biology of multitrophic interaction (plant-disease causing bacteria and insect vector), plant and Agrobacterium molecular biology and horticulture. It also includes advanced manufacturing expertise at the IRSC Advanced Manufacturing Hub, Fort Pierce, FL. Methods will include: 1) greenhouse and field studies of symbiont formation as influenced by plant x bacterial genotype interactions; 2) manufacturing and testing of devices for rapid delivery and containment of symbionts. Delivery and containment devises will be fabricated through either milling, CNC, 3D printing or a combination of these fabrication methods and testing will be performed in field plots. For direct DNA delivery experiments it is understood that citrus trunk bark on mature trees will be more recalcitrant to DNA delivery than greenhouse potted plants. Experimental designs to address this are already developed.