The microbiome as an extension of the plant immune system: the role of microorganisms associated with the cacao tree in witches' broom disease resistance

• Grant number: 24/11510-4
• Support Opportunities: Scholarships in Brazil - Support Program for Fixating Young Doctors
• Start date: September 01, 2024
• End date: August 31, 2026
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Agreement: CNPq
• Principal Investigator: Paulo José Pereira Lima Teixeira
• Grantee: Letícia Bianca Pereira
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated research grant: 24/02248-4 - The microbiome as an extension of the plant immune system: the role of microorganisms associated with the cacao tree in witche's broom disease resistance, AP.R

Abstract

Plant diseases are commonly investigated as binary relationships between a plant and a pathogen. However, recent studies have shown that microorganisms naturally associated with plants (i.e., microbiomes) also participate in these interactions and influence the development of the disease. However, little is known about how the microbiome interacts with the plant immune system or with phytopathogenic microorganisms. Knowledge and manipulation of plant microbiomes, especially those of commercial interest, can offer possibilities for improving agronomic characteristics in crops. The cocoa tree is an important crop for Brazil, but its production is severely damaged by the witches' broom disease, caused by the fungus Moniliophthora perniciosa. The present proposal aims to investigate how witches' broom disease affects the microbiome of cocoa tree shoots. This will be accomplished by sequencing regions of the ribosomal gene of bacterial and fungal communities that colonize shoots of healthy plants and those infected by M. perniciosa. Our hypothesis is that microorganisms that are efficient in competing with the fungus M. perniciosa are present in greater abundance in infected tissues. Furthermore, a collection of microorganisms associated with the cacao plant will be constructed through the isolation of fungi and bacteria from healthy shoots and those infected by M. perniciosa. This collection will be used in a large-scale screening to identify strains that can mitigate the development of witches' broom in cacao plants. These efforts will expand our understanding of the effect of disease on the plant microbiome and may support the future development of effective biofungicides. (AU)