Asian Citrus Psyllid Feeding Behavior in Citrus Treated with Specific and Non-Specific dsRNA

Abstract

The potential of RNA interference (RNAi) technology to control the Asian Citrus psyllid (ACP), vector of Huanglongbing (HLB), has been demonstrated in different publications. RNAi is a natural biological process that specifically down regulates the expression of a specific gene, being more environmentally friendly approach to control insects. We´re interested to understand if the treatment of a plant with dsRNA could induce an ACP response. To evaluate if ACP sense the presence of a dsRNA (ACP-specific and non-specific) in plants, we set up free of choice experiments to examined psyllid response to dsRNA treated plants versus non-treated plants, to dsRNA-specific versus dsRNA non-specific and plants treated with two dsRNA-specific. Four groups of 4 plant flush each (2 of each treatment) were placed in each corner of a cage, and 50 ACP were release at the center. They were observed for 15 d, and the number of ACP on each flush recorded daily. Each experiment was repeated at least four times. No significant differences, using F-test analyses, was observed in ACP feeding preferences regarding the presence of dsRNA (p< 0,05). These preliminary results suggest that psyllids appear not to be sensitive to dsRNA ingestion, as they may be for traditional chemical insecticides, thus were not repelled.