Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/14/2010
Publication Date: 6/16/2010
Citation: Hunter, W.B., Glick, E., Bextine, B.R., Paldi, N. 2010. RNAi delivery-whole plant systems reducing psyllids and leafhoppers [abstract]. National Citrus Research Coordination Symposium, June 16-18, 2010, Denver, Colorado. Interpretive Summary:
Technical Abstract: We developed a system for delivery of dsRNA constructs in whole-plant systems (herbaceous plants, woody grapevine and citrus seedlings and trees) which is currently being evaluated. Successful feeding of dsRNA in sucrose solutions to psyllids was followed by using flush shoots excised from trees. Treatments of seedlings showed that dsRNA could be introduced into whole plant systems. Citrus trees, approximately 2.5 m tall, are being screened for dosage requirements, uptake time, and persistence within plant tissues. These trees are 6 year old key lime which produce fruits that will be examined for presence and/or persistence of dsRNA constructs. Trials to determine soil effects showed no inhibition of uptake. RNA interference technology (RNAi) has been used successfully to silence endogenous insect (including honey bee) genes both by injection and feeding, and in plants (genetically modified). Previously, RNAi was used successfully to prevent bees from succumbing to infection from a viral disease, and dsRNA was shown not to persist in bees nor honey once treatment was stopped. Trials are being developed for applications to mature fruiting trees to determine efficiency of uptake, dosage titers, and residue time to breaking down in trees, fruits, and juice. We propose that in the case of citrus pests (ie. psyllids, leafhoppers, and whiteflies) specific insect transcripts can be used to reduce and suppress psyllids in an area-wide program using RNAi strategies.