Protocol setting for double-strand delivery RNA (dsRNA) and evaluation of the effects of RNAi in Brevipalpus yothersi (Acari: Tenuipalpidae) - the citrus leprosis vector

• Grant number: 16/12912-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2016
• End date: July 31, 2018
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Valdenice Moreira Novelli
• Grantee: Letícia Montelatto
• Host Institution: Instituto Agronômico (IAC). Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). Campinas , SP, Brazil
• Associated research grant: 14/08458-9 - Plant viruses transmitted by Brevipalpus mites (Acari: Tenuipalpidae) - BTV: survey, identification, molecular characterization, phylogeny; virus/vector/host relationhip; biology, taxonomy and management of the mite, AP.TEM

Abstract

The leprosis is one of the most important viral diseases of citrus, caused by Citrus leprosis virus (CiLV-C, Cilevirus), transmitted by Brevipalpus mites (Acari: Tenuipalpidae). In plants the symptoms are local, characterized by chlorotic and necrotic lesions on fruit, branches and leaves, and in advanced stage of the disease lead to death of the plant. The treatment in orchards is basically done with the use of acaricides for vector control, increasing production costs and risks environmental damage. Efficient and sustainable strategies are highly desirable in the management of diseases and the use of techniques in molecular biology is an alternative that has been investigated for the citrus industry, such as RNA interference technology (RNAi) for the control of insect vectors, but still no explored for mites. Promising results, including exploration and validation of target genes for RNAi were obtained in studies conducted in Centro de Citricultura "Sylvio Moreira"-IAC (CCSM-IAC), in partnership with other research institutions. From these data, the objectives of this study are to establish an efficient protocol for administration of dsRNA molecules (delivery of dsRNA) and evaluate the effect of this treatment for leprosis mite (Brevipalpus yothersi Baker). The best strategy dsRNA administration will be determined by assessing different methods of dipping and orally, using as commercial dyes which control and setting mite development stage there is greater expression of target genes. The functional effect of RNAi should be assessed by comparing the expression of target genes between treated and untreated mites. The expectation is to contribute to basic information for establishing the RNAi technique, as an innovative strategy in the control of the mite of citrus leprosis disease. (AU)