Gene silencing by interfering RNA in Brevipalpus yothersi (Acari: Tenuipalpidae)

Abstract

False spider mites - Brevipalpus (Tenuipalpidae) are responsible for the transmission of innumerable plant viruses, among them citrus leprosis. Considered one of the most important viral diseases of citrus, leprosis is commonly transmitted by B. yothersi and caused by Citrus leprosis virus (CiLV-C, Cilevirus). In plants, the symptoms are restricted to mite feeding sites, characterized by chlorotic and necrotic lesions in fruits, branches, and leaves, and can lead to the death of the plant at an advanced stage of the disease. In citrus orchards, the management is primarily done by the use of acaricides with high costs in production, risks to human health and contamination of the environment. More sustainable and efficient control strategies are highly desirable for these types of pests and diseases. Genomic knowledge of pests, together with molecular techniques, represent an alternative with great potential, but still little explored for citriculture. Interfering RNA (RNAi) technology, by dsRNA delivery, is one of these strategies for vector control and has been gradually studied. Based on the B. yothersi genome, promising results were obtained in the prospection of target genes for RNAi and in the establishment of a protocol for delivery, in a study recently conducted at the "Sylvio Moreira" -IAC (CCSM-IAC) of dsRNA, also suggesting an alteration in the gene expression of B. yothersi. In this way, the objectives of this work will be to analyze the level of expression of three functional genes in different stages of development of the false spider mite, and to select one of them as a target for dsRNA delivery, evaluating the effects at expression and mortality of individuals due to silencing. The results obtained will add scientific knowledge regarding the RNAi technique in mites, as well as subsidies for a future alternative strategy to control the vector of citrus leprosis.