Assessment of the impact of the release of predatory mites (Phytoseiidae) on citrus and vegetables for the biological control of arthropod pests: monitoring using molecular markers

• Grant number: 24/12802-9
• Support Opportunities: Scholarships in Brazil - Support Program for Fixating Young Doctors
• Start date: August 01, 2024
• End date: July 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Agreement: CNPq
• Principal Investigator: Mário Eidi Sato
• Grantee: Maria Cristina Vitelli Queiroz
• Host Institution: Instituto Biológico (IB). Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 24/02308-7 - Assessment of the impact of the release of predatory mites (Phytoseiidae) on citrus and vegetables for biological control of arthropod pests: monitoring using molecular markers, AP.R

Abstract

Brazilian citrus farming, which holds global leadership, has stood out for promoting socioeconomic growth, contributing to the national trade balance and, mainly, as a direct and indirect generator of jobs in rural areas. Some pests are economically important because they are vectors of pathogens in citrus, such as Diaphorina citri (HBL) and Brevipalpus sp (CiLV). Vegetable agribusiness allows the generation of a large number of jobs, especially in the primary sector, due to the high demand for labor in the various stages of production, including sowing, cultural treatments, harvesting, processing and marketing. In vegetables, viruses can be transmitted by whiteflies (Bemisia tabaci) and thrips. In both cases, disease control mainly consists of eliminating vectors using agrochemicals. The use of Phytoseiidae predatory mites represents one of the most promising strategies for pest control in commercial fruit, vegetable and ornamental production systems. In addition to consumption, the simple presence of the predator can alter the pest's behavior, potentially reducing damage. However, the application of chemical products (e.g. insecticides) to these crops can drastically affect predator populations. The use of strains of predators resistant to broad-spectrum compounds can enable the use of these natural enemies for biological control, in crops where the farmer applies agrochemicals. The introduction of special species and/or strains into biological systems always needs to be monitored. The objective of this research is to monitor the establishment and dispersion of resistant populations introduced in citrus and horticultural agrosystems, as well as to study the trophic chain between the species involved, in order to evaluate the impact of predators on pests, transmitted diseases and other organisms. The proposed work includes the use of molecular markers to analyze the spatial reach of populations released into agricultural crops and also the gene flow between these and native populations, with possible dilution of the characters of interest (pesticide resistance). In the same way, the trophic chain will be analyzed, seeking to understand the food preferences of the released predators. The behavioral changes of phytophagous arthropods in the presence of predator signals will be studied through the analysis of volatile organic compounds (VOCs) involved in the tritrophic relationships between plant, pest and predator. The results of these studies can provide relevant information for defining vector management strategies, aiming to reduce the damage caused by transmitted diseases. (AU)