Suppressive phyllosphere in eucalyptus: sustainable innnovation for the management of myrtle rust

• Grant number: 24/05484-0
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2024
• End date: July 31, 2026
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Thaís Regina Boufleur
• Grantee: Thaís Regina Boufleur
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated researchers: Benjamin Schwessinger ; Fábio Prataviera ; Lilian Amorim ; Luciana Duque Silva ; Maria Carolina Quecine Verdi ; Nelson Sidnei Massola Júnior
• Associated scholarship(s): 25/09723-2 - Quantification and morphological characterization of the phyllosphere microbiome of eucalyptus during interaction with Austropuccinia psidii, BP.IC; 24/16205-5 - Modulation and characterization of a phyllosphere suppressive to myrtle rust(Austropuccinia psidii) in eucalyptus, BP.MS

Abstract

The eucalyptus (Eucalyptus spp.) belongs to the Myrtaceae family and is the most widely planted species for wood, pulp and derivative production. Over the past 50 years, Austropuccinia psidii, the causal agent of myrtle rust, has posed a constant threat to eucalyptus production and the biodiversity of native forests, ranking among the top ten most feared fungi globally. While in Brazil A. psidii populations are structured by the host, the rest of the world experiences a predominance of a pandemic population pathogenic to hundreds of species within the Myrtaceae family. The most commonly used control strategies in commercial cultivation of eucalyptus are genetic resistance and chemical control. However, new public policies focused on agroecosystem sustainability have redirected the search for plant disease management strategies. Within these, one of the most promising tools in the long term is the plant microbiome. There still is a considerable gap between microbiome characterization and translating knowledge into field-applicable strategies. The strategy begins with the exploration of microbial communities with the potential to suppress the progression of the disease. Hence, host-microorganism co-evolution is a significant ally, leading to the emergence of disease-suppressive environments due to microbial communities present either in the soil or the phyllosphere. Thus, this project aims to (i) modulate the eucalyptus phyllosphere using field microbial communities, under selection pressure from distinct A. psidii isolates, to reduce rust severity; (ii) characterize changes in the developed phyllosphere microbial community over time; and (iii) identify similarities among the phyllosphere microbiomes identified in (ii) in the search for a core microbiome. The development of a suppressive phyllosphere and the analysis of modulated microbial communities are crucial for exploring innovative and sustainable approaches in controlling myrtle rust in eucalyptus and other Myrtaceae species. (AU)