Banca de DEFESA: MILENA PUPO RAIMAM

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MILENA PUPO RAIMAM
DATE: 02/02/2024
TIME: 08:30
LOCAL: Auditorio PGAGRO, Solos
TITLE:

"RECYCLING OF STEEL WASTE IN THE PRODUCTION OF EUCALYPTUS SEEDLINGS MEDIATED BY BIOSTIMULATION WITH Bacillus sp."

KEY WORDS:

Steel Slag; Recycling; Rhizobacteria, Eucalyptus, Photosynthesis.

PAGES: 132
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Fitossanidade
SPECIALTY: Microbiologia Agrícola
SUMMARY:

Brazil is the 9th major steel producer in the world and 1st in Latin America, having produced 36 million tons in 2021. Steel production is complex, involves several operations and types of inputs and is intrinsically associated with the generation of by-products (waste).  The charcoal used as reducing power, is produced from eucalyptus forests established with cuttings and minis cuttings, however clones have variability in the pattern of development of the root system which impacts the growth and adaptability of these to different environmental conditions. On the other hand, the management of the by-products that are part of steelmaking has become a worldwide goal in the race to produce "green steel". Electrical steel slag (ESA), a by-product of steel refining, is promising for agriculture due to its nutrient content (CaO, FeO, MgO, SiO), however the presence of heavy metals has been a challenge for its insertion in agricultural and forestry crops.  The use of plant growth promoting bacteria (PGPB) improves seedling development and growth through individual or combined biochemical mechanisms that result in better hormonal balance, increased nutrient uptake, and enhancement of plant resistance to biotic and abiotic environmental stresses. Thus, the general objective of this research was to obtain PGPB to improve the quality of eucalyptus seedlings and to test the combination of these with EAE, as a strategy for the final destination of this by-product. Rhizobacteria were isolated from the steel waste deposit area in the municipality of Marabá, PA and screened for their potential to promote growth in a greenhouse. The rhizobacterium Bacillus sp. CCMD862 was combined with EAE and the effects on the physiological variables of gas exchange and chlorophyll fluorescence a, biometry, biomass, nutrient and heavy metal content and sugar content in eucalyptus seedlings (Corymbia tolleriana x Corymbia citriodora) were evaluated. The combination Bacillus sp. CCMD862 + EAE promoted increases in length and volume root, root dry biomass and root/aerial part ratio. The increased growth was related to improved photochemical performance, resulting in higher net photosynthesis. The application of EAE in eucalyptus nutrition receives an additional advantage when associated with biostimulation with Bacillus sp. CCMD862, and may represent an excellent strategy to accelerate growth and increase seedling robustness, reduce production costs, and prevent damage to the environment. The incorporation of eletrical steel slag in the production chain of eucalyptus is a potential route of destination of this waste that still accumulates in mills in the country.

BANKING MEMBERS:
Presidente - 1551252 - GISELE BARATA DA SILVA
Externa à Instituição - ANGÉLICA FERNANDES DEUS
Externo à Instituição - DALTON DIAS DA SILVA JUNIOR - UFAM
Externa à Instituição - FERNANDA ILKIU BORGES DE SOUZA - EMBRAPA
Externa à Instituição - MARIA CAROLINA QUECINE VERDI - USP