1a. Objectives (from AD-416)
To determine the feasibility of using a bait formulation to deliver double stranded RNA (dsRNA) complimentary to the yolk protein receptor (VgR) specific to fire ant queens to stop egg-laying.
1b. Approach (from AD-416)
1) Design dsRNA to VgR from the fire ant. 2) Synthesize a dsRNA VgR that is stable and transportable across the ant digestive system via aliphatic-PEG polymer technology (NC State University patent pending). 3) Evaluate the activity of injected VgR dsRNA versus aliphatic PEG dsRNA on Vg synthesis and egg laying in fire ant queens. 4) Evaluate effects of VgR dsRNA versus aliphatic PEG dsRNA provided in nectar or other food substances by colony feeding on Vg synthesis and egg laying in fire ant queens.
3. Progress Report
This project is related to Objective 3 of this in-house project: Characterize semiochemicals through investigation of pheromone biosynthesis and release; use these findings to develop novel biologically-based control and surveillance methods, including the detection and treatment of incipient or low level populations. The objective of this cooperative research project is to determine the feasibility of bait delivery of RNA interference to silence the vitellogenin receptor (VgR)in fire ant queens and thus disrupt egg production. Fire ant VgR silencing has been reported, and it offers the opportunity to provide species specificity not available with currently marketed ant baits. Solutions of RNA interference were fed directly to fire ant queens, but the queens still produced eggs. This result may be indicative of RNA degradation in the ants’ digestive system, thus RNA that is stabilized and transportable across insect digestive systems will be evaluated. Project was just recently approved, thus there is no progress to report at this time. Progress on this project was monitored by means of frequent email and telephone communications.