Evaluation of controls for RNA interference strategy, in dsRNA delivery to citrus leprosis mite

• Grant number: 19/22449-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2020
• End date: January 31, 2021
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Valdenice Moreira Novelli
• Grantee: Laura Leme Zanesco
• Host Institution: Instituto Agronômico (IAC). Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). Campinas , SP, Brazil

Abstract

Citriculture is one of the main agricultural activities in the world, with Brazil standing out in its production focused on exporting concentrated juice and the gradual increase in fruit consumption. However, there are many biotic and abiotic problems to management in citrus orchards. Among these, citrus leprosy is one of the diseases with the greatest economic impact. Of viral origin, it is commonly transmitted by the Brevipalpus yothersi mite and is caused by the citrus leprosy virus (CiLV-C, Cilevirus). Symptoms are restricted to mite feeding sites, with necrotic and/or chlorotic lesions in fruits, branches, leaves and which, at an advanced stage, can lead to plant death. The damages can be high and irreversible to the producers, demanding permanent control in the orchards, mainly through acaricides. Vector genetic information represents an approach that in the near future may offer subsidies for mite control to sustainable citrus orchards. At CCSM-IAC, to silence essential vector genes by delivering double-stranded RNA (dsRNA) is a research, with a view to the functional genetic knowledge of the mite and the possible application of the RNAi as a future strategy to control mite vector. Thus, the RNAi application requires controls to validate the treatment and observe the silencing of target genes. Therefore, this proposal is to evaluate different molecules for oral delivery of target dsRNA to mites. The sequences of the GUS reporter gene (B-glucuronidase) and an intergenic B. yothersi region will be used for dsRNA synthesis and compared with dsRNA-GFP, the current standard control in RNAi experiments. This information will be essential to establish the best control of target dsRNA delivery and to evaluate the effects of gene silencing on the citrus leprous mite. (AU)