Banca de DEFESA: DÉBORA CRISTINA LUCAS DOS SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : DÉBORA CRISTINA LUCAS DOS SANTOS
DATE: 31/03/2022
TIME: 08:30
LOCAL: https://conferenciaweb.rnp.br/conference/rooms/margarida-gorete-ferreira-do-carmo/invite
TITLE:

Identification of Bacillus spp. strains efficient in the control of tomato fusarium wilt and mechanisms involved

KEY WORDS:

Vascular wilt, Biological control, Solanum lycopersicum, Endophytes.

PAGES: 70
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Fitotecnia
SUMMARY:

Tomato (Solanum lycopersicum L.) is one of the most produced and consumed vegetables in Brazil and in the world, with great social and economic importance. It is susceptible to several diseases that can cause great losses in productivity and fruit quality. Among these is fusarium wilt, caused by the fungus Fusarium oxysporum f. sp. lycopersici (Scc.) Snyder and Hansen (Fol) which is one of the most limiting diseases to tomato production. It is a hemibiotrophic pathogen with host specificity, at the species and variety level, and survival in cultural remains and in the soil. Once introduced, it can settle down and stay for a long time. The use of resistant
cultivars is the most efficient control strategy, but it can be affected by the selection and dissemination of new races. Biological control with antagonistic microorganisms is one of the alternatives that has been most investigated in order to suppress the disease. Among the organisms most used in the biocontrol of diseases are Bacillus species, and among the control mechanisms involved is the production of bioactive compounds with an antagonistic effect to the pathogen or with effects on the plant as inducers of systemic resistance or growth promoter. In 2015, different strains of Bacillus were isolated from healthy tomato plants collected in the
municipality of Nova Friburgo, RJ, where Fol is widely disseminated. Sixty bacterial isolates from this collection were submitted to in vitro antagonism tests against Fol and eight of them were selected due to their ability to reduce by at least 50% the mycelial growth of the phytopathogen. DEST 30, DEST 31, DEST 38, DEST 60, DEST 78, DEST 83, DEST 132 and DEST 138 were then subjected to taxonomic and functional characterization. The first was performed by sequencing the 16S rRNA subunit. As for the functional characterization, the strains were submitted to a series of in vitro tests where all strains showed proteolytic activity and were able to produce siderophores, most also showed cellulolytic and pectinolytic activity. From the results obtained in these tests, the bacteria, DEST 31, DEST 60, DEST 83 and DEST 132 were selected to be tested as biocontrol agents of fusarium wilt in tomato seedlings grown in a greenhouse, however they did not promote results significant benefits against the disease.

BANKING MEMBERS:
Presidente - 1213072 - MARGARIDA GORETE FERREIRA DO CARMO
Externo à Instituição - CARLOS ANTÔNIO DOS SANTOS
Externa à Instituição - MARCIA REED RODRIGUES COELHO - EMBRAPA