Banca de QUALIFICAÇÃO: MARIANA BESSA DE QUEIROZ

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARIANA BESSA DE QUEIROZ
DATE: 04/06/2025
TIME: 13:30
LOCAL: meet.google.com/tbt-ihhy-gpk
TITLE:

SOIL MYCOBIOME UNDER DIFFERENT LAND USES IN THE SOUTHERN AMAZON: A METATAXONOMIC APPROACH

KEY WORDS:

Agriculture, fungal diversity, metabarcoding, taxonomy, next-generation sequencing (NGS).

PAGES: 131
BIG AREA: Ciências Biológicas
AREA: Microbiologia
SUBÁREA: Biologia e Fisiologia dos Microorganismos
SPECIALTY: Micologia
SUMMARY:

Fungi represent a highly diverse and widely distributed taxonomic group, playing essential roles in ecosystem functioning. Understanding fungal community structure across different land-use systems is crucial for elucidating their roles in environmental dynamics and their potential contributions to sectors such as agriculture. Although the Amazon harbors a rich diversity of plant species that support a wide range of soil fungi, it remains the least studied Brazilian biome in terms of fungal diversity. In this study, we collected soil samples from a native forest area within Cristalino State Park, Mato Grosso, and from an adjacent area recently converted into an agricultural system. Our goal was to characterize fungal communities and ecological guilds using a high-throughput sequencing (NGS) approach, with a parallel focus on the identification of arbuscular mycorrhizal fungi (AMF). The ITS region was used to characterize general fungal communities, while the LSU region targeted AMF assemblages, complemented by morphological analysis of spores. While ITS amplicon libraries are still under processing, LSU sequencing revealed 63 operational taxonomic units (OTUs) at the species level, including seven OTUs representative of previously undescribed genera. Additionally, 41 AMF morphospecies were identified. Both alpha and beta diversity differed between the two sites. Alpha diversity was higher in agricultural soils, associated with increased pH and nutrient availability (Ca, Mg). In contrast, forest soils exhibited ultra-acidic conditions (pH= 2.7), which were linked to lower diversity in this environment. Beta diversity was primarily influenced by soil pH, followed by P, K, Ca, and sand content. Amazonian soils harbor a high richness of AMF, including potential new species. Although land-use conversion alters AMF community structure, it does not lead to reduced richness or diversity. The observed changes are primarily driven by differences in soil properties, with less acidic and moderately more fertile environments supporting greater species diversity.

COMMITTEE MEMBERS:
Presidente - 1755051 - BRUNO TOMIO GOTO
Externa à Instituição - JULIANA APARECIDA DOS SANTOS
Externa ao Programa - ***.585.804-** - KÁSSIA JÉSSICA GALDINO DA SILVA SCHINAIDER - UFRN