SUSCEPTIBILITY TO ACARICIDES AND ANALYSIS OF THE GENETIC AND POPULATION VARIABILITY OF Brevipalpus yothersi IN THE BRAZILIAN CITRUS BELT.

• Grant number: 24/21543-7
• Support Opportunities: Regular Research Grants
• Start date: September 01, 2025
• End date: August 31, 2027
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Daniel Júnior de Andrade
• Grantee: Daniel Júnior de Andrade
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated researchers: Andressa de Souza Pollo ; Juliana de Freitas Astúa

Abstract

Citriculture is of great economic importance to Brazil, the largest producer and exporter of oranges in the world. However, this crop faces several phytosanitary challenges, particularly citrus leprosis, caused by the Citrus leprosis virus (CiLV-C), whose vector is the mite Brevipalpus yothersi. Citrus leprosis control is primarily carried out through the application of synthetic acaricides to manage the mite vector. Nevertheless, the evolution of resistance to acaricides has become one of the primary challenges faced by citrus producers. Selection pressures on B. yothersi populations, such as the frequency and type of acaricide applications, have probably led to an increase in the genetic variability of mite populations in Brazil. Studies suggest that although B. yothersi reproduces clonally, genetically distinct haplotypes may be associated with the host citrus variety. Given the cryptic nature of the B. phoenicis complex, from which B. yothersi is derived, population phylogenetic studies are required to correlate mite genetic variability with sensitivity to the active ingredients of available acaricides. Therefore, this project aims to monitor the susceptibility of B. yothersi populations from commercial citrus orchards in the state of São Paulo to the main acaricides currently in use, and to correlate these results with population phylogenetic analysis, obtained through sequencing of the 28S and ITS ribosomal regions, and the mitochondrial gene COI. (AU)