Co-culture strategy between the endophytic fungus Pseudopithomyces sp. and the Citrus sinensis phytopathogen P. digitatum based on metabolomic analyses for the exploration of antifungal secondary metabolites

• Grant number: 25/23889-0
• Support Opportunities: Scholarships in Brazil - Program to Stimulate Scientific Vocations
• Start date: January 30, 2026
• End date: March 14, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Organic Chemistry
• Principal Investigator: Taicia Pacheco Fill
• Grantee: Ana Rute Souza Ferreira
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Citrus cultivation stands out worldwide as one of the most profitable and strategic sectors of agribusiness, with oranges being the most produced and consumed citrus fruit on the planet. In Brazil, this production chain represents one of the most established activities in the sector, occupying a leading position in the total value of national fruit production. However, postharvest diseases remain one of the greatest challenges in citrus production, compromising fruit quality and causing significant economic losses. Among the main agents responsible for these diseases are decomposing fungi, which deteriorate large volumes of fruit after harvest. Among them, the fungus Penicillium digitatum, the etiological agent of green mold, is the most common phytopathogen affecting citrus fruits, capable of causing losses of up to 90% in severe cases. The control of these postharvest diseases has traditionally relied on the use of synthetic fungicides, whose extensive application poses serious risks to human health and the environment. In this context, interest in sustainable alternatives has grown, such as the use of endophytic fungi-microorganisms that inhabit plant tissues without causing apparent harm to their hosts-as biocontrol agents. However, in recent decades, the discovery of new fungal metabolites through conventional monoculture methods has decreased considerably. Promisingly, recent studies have shown that the co-culture strategy is an effective approach to activate silent biosynthetic gene clusters responsible for the production of secondary metabolites in fungi. Thus, this project aims to conduct a chemical and metabolomic study of co-cultures between endophytic fungi isolated from Citrus sinensis (var. Pera), particularly Pseudopithomyces sp., and the phytopathogen P. digitatum, under in vitro conditions. The goal is to identify new bioactive secondary metabolites produced during the endophyte-pathogen interaction, with antifungal potential and applicability in the biological control of citrus diseases. (AU)