Banca de DEFESA: THAMIRES FERREIRA RODRIGUES DA SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : THAMIRES FERREIRA RODRIGUES DA SILVA
DATE: 26/05/2021
TIME: 09:00
LOCAL: vídeo conferência
TITLE:

Response to the inoculation of diazotrophic and growth promoting bacteria in different genotypes of Brachiaria

KEY WORDS:

Biological Nitrogen Fixation, Pastures, Nitrogen.

PAGES: 50
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SUMMARY:

The Brazilian livestock sector is benefited by favorable climatic and edaphic factors that make the extensive cattle production system more practical and economically viable. However, the use and management of pastures must be adequate, in order to maintain soil fertility and consequently good pasture productivity. The use of plant growth promoting bacteria (PGPB) is an alternative to increasing the efficient use of nitrogen by plants, either by promoting biological nitrogen fixation and the production of plant growth regulators. The aim of this work is to identify positive interactions between genotypes of Brachiaria and PGPB by optimizing the beneficial interaction between these organisms for use in grass. The first experiment was evaluated the initial growth of genotypes of Brachiaria spp. with or without the inoculation of bacterial strains (Ab-Sp245, Hs-ZAE94, Hs- HRC54 and Na-CBAmc) with five repetitions in entirely randomized design. The variables analyzed were aerial and root mass, and with the analysis of the roots by the WinRHIZO Pro 2016® software, were obtained the following parameters: Length, Volume, Surface Area and Diameter. The mean values obtained were evaluated for normality (Shapiro-Wilk) and homogeneity (Barlett), the analysis of variance and the F test were obtained using the R software with 95% confidence. The second experiment analyzed the association of Ab-Sp245 pLMB426 in root tissues by the confocal fluorescence microscope model LSM700 (Carl Zeiss). The genotypes responded differently to each strain in all the variables analyzed, however the Basilisk, Ruziziensis and Convert HD364 genotypes when inoculated showed increases in mass and root length, indicating greater susceptibility to the association of BPCP in these genotypes. In addition, it was also possible to observe clusters of bacterial cells on the root surface or rhizosphere of the Marandú cultivar and the Convert HD364 hybrid demonstrating that improvements in root parameters were achieved by positive plant x bacterial interaction. In short, the inoculation with BPCP strains in Brachiaria spp. in vitro shows great potential for improving root characteristics in the early stages of growth and development.

BANKING MEMBERS:
Interna - 1815763 - IRENE DA SILVA COELHO
Externo à Instituição - STEFAN SCHWAB - EMBRAPA
Presidente - 631.052.847-53 - VERONICA MASSENA REIS - EMBRAPA