Banca de DEFESA: JUAN RIBEIRO FERREIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JUAN RIBEIRO FERREIRA
DATE: 27/10/2022
TIME: 09:00
LOCAL: On-line
TITLE:

Selection of endophytic bacteria of the genus Bacillus with antagonistic activity to the phytopathogen Colletotrichum falcatum that causes red rot in sugarcane. 

KEY WORDS:

Saccharum spp. Phytopathogen. Biocontrol. Plant growth promoting bacteria.

PAGES: 50
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Fitotecnia
SPECIALTY: Manejo e Tratos Culturais
SUMMARY:

Brazil has a prominent position in the world in terms of the production of sugarcane and its derivatives. However, the productivity of sugarcane crops is threatened by red rot, a disease caused by the pathogen Colletotrichum falcatum. Sustainable alternatives such as biological control are a relevant tool to be integrated into the management of this disease in sugarcane. In this sense, the search for biotechnologies to combat this injury is relevant and one of the first steps for this is the selection of efficient strains to combat this phytopathogen. And within this context, bacteria of the genus Bacillus stands out, which has several species with recognized ability to control a great versatility of agricultural pests. Therefore, this work aimed to select bacteria isolated from sugarcane plants of the genus Bacillus and test them in vitro against relevant characteristics for biological control. For that, bacterial isolates of the genus Bacillus were tested against the antagonistic capacity to different strains of C. falcatum and cellulolytic activities, production of hydrocyanic acid and proteolytic activity of these bacteria were evaluated. Assays were performed in triplicate and the results were submitted to analysis of variance (ANOVA) using the F test and comparing means using the Scott-Knott test. Of the 54 bacterial strains tested, 16 showed antagonism above 90% against the MMBF 12/05 isolate of the fungus C. falcatum. The species B. amyloliquefaciens, B. methylotrophicus, B. yelezensis and B. tequilensis showed greater antagonism against the isolates MMBF 12/02, IAC 15, IAC 38 of C. falcatum. Strains of the same species of Bacillus from the same niche showed different efficiency in the antagonism of C. falcatum according to the phytopathogen strain tested. None of the bacteria tested showed the ability to produce HCN, even those that were antagonistic to the fungus. Indicating that this is not the mechanism used by these strains. Most strains showed proteolytic activities than cellulase production, which may indicate a more prominent role of proteases in the inhibition of C. falcatum by the Bacillus species tested.

BANKING MEMBERS:
Presidente - ***.210.947-** - MARCIA SOARES VIDAL - EMBRAPA
Interna - 1213072 - MARGARIDA GORETE FERREIRA DO CARMO
Externa à Instituição - MARCIA REED RODRIGUES COELHO - EMBRAPA