Formulations of bacteriophage lytic to Xanthomonas citri: a sustainable alternative for citrus canker management.

• Grant number: 25/05869-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: August 01, 2025
• End date: July 31, 2027
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Henrique Ferreira
• Grantee: Daniel Fernandes Mendes
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Associated research grant: 21/10577-0 - Biology of Bacteria and Bacteriophages Research Center, AP.CEPID

Abstract

Citriculture is one of the most significant agricultural activities in Brazil, with the State of São Paulo being the world's largest producer of sweet oranges. Among the numerous threats to citrus production, citrus canker, caused by the Gram-negative bacterium Xanthomonas citri subsp. citri (X. citri), is an untreatable disease that leads to substantial economic losses. Disease management primarily relies on frequent applications of copper-based bactericides, which have been linked to bacterial resistance and environmental harm. Bacteriophages, natural predators of bacteria, have emerged as biocontrol alternatives for various economically important plant cultures. Although effective, phage stability, survival and durability on leaves are some of the factors that must be addressed in order to overcome some challenges in using bacteriophages as a sustainable management alternative. Therefore, we intend to produce formulations having encapsulated phage aiming at virion survival and bioavailability. These formulations will be evaluated for their particle size, stability, phage protection capability under different stress conditions and assess their effectiveness in protecting plants from citrus canker. (AU)