Banca de QUALIFICAÇÃO: THAIS ALMEIDA CORREA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : THAIS ALMEIDA CORREA
DATE: 22/05/2025
TIME: 13:00
LOCAL: Online pelo Google Meet
TITLE:

Interactions between entomopathogenic fungi and their hosts: Immune response in larvae of the insect Noctua pronuba and diversity of the intestinal microbiota of the tick Rhipicephalus microplus when challenged with fungi

KEY WORDS:

tick-borne pathogens; entomopathogenic fungi; functional composition; network modulation

PAGES: 79
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUBÁREA: Medicina Veterinária Preventiva
SPECIALTY: Doenças Parasitárias de Animais
SUMMARY:

The entomopathogenic fungus Metarhizium anisopliae can be used as a sustainable biocontrol agent against Rhipicephalus microplus, an important vector of Anaplasma marginale, which causes bovine tick fever and significant economic losses. The present study explored the changes in the tick gut bacteriome in response to fungal and Anaplasma marginale infection by a metabarcoding approach considering V3-V4 region of the bacterial 16S rRNA gene. Experimental groups were established under four conditions: guts from Metarhizium-untreated females, either uninfected (CTR-) or infected with Anaplasma (CTR+); and guts from Metarhizium-treated females, either uninfected (Ma-) or infected with Anaplasma (Ma+). According to the biomarker analysis (LEfSe), the guts of CTR- and Ma+ exhibited the highest number of associated taxa (eight each), while CTR+ and Ma- had only three biomarkers each. The gut microbiota preserved a stable taxonomic composition, with Bacteroidota and Bacillota as the dominant phyla, with no significant differences in alpha diversity between the groups. Despite this, co-occurrence network analysis indicated that the guts from Ma- had greater resilience, preserving network connectivity even with node removal, whereas the guts from CTR+ were the most fragile. Functional prediction exhibited greater functional diversity in the guts of CTR+ and Ma+, suggesting that A. marginale infection increases the abundance of specific functional genes. This is the first report of bacteriome analysis in the context of Metarhizium and Anaplasma infection, highlighting the importance of understanding how treatment with M. anisopliae modulates the gut microbiota of R. microplus in the presence of A. marginale, thus providing valuable insights into optimizing integrated control strategies.

COMMITTEE MEMBERS:
Presidente - 2221855 - PATRICIA SILVA GOLO
Externa ao Programa - 145.550.827-61 - EMILY MESQUITA DA SILVA
Externa ao Programa - 1815763 - IRENE DA SILVA COELHO - UFRRJExterna à Instituição - LARISSA ALMEIDA MARTINS