Banca de DEFESA: MARIANA ROCHA DE CARVALHO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE: MARIANA ROCHA DE CARVALHO
DATA: 26/03/2024
HORA: 14:00
LOCAL: Anfiteatro Setor de Fisiologia Vegetal
TÍTULO:

Potentially toxic elements from phosphate fertilizers to crops: mobilization and mitigation

PALAVRAS-CHAVES:

Keywords: food safety, liming, phosphate fertilizers, phytochelatin, plant nutritional, selenium. 

PÁGINAS: 1
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
RESUMO:

Phosphorus (P) is one of the most important macronutrients for plants and adequate inputs of P in the soil are essential for food production. However, phosphate rocks may naturally contain different levels of contamination by potentially toxic elements (PTEs), like arsenic (As), cadmium (Cd), and chromium (Cr). Among the three selected elements, Cd is the most easily bioavailable to the plants, and so to the food chain. So, this element has been a stepping-stone toward achieving sustainable and safe worldwide food production, especially after a new regulation aiming for reduced limits of Cd in P fertilizers (EU 2019/1009). Soil pH increase is one of the effective strategies to cope better with Cd in soil, as well as mineral supplemental with antagonist elements to Cd, like selenium (Se). In this context, this study aimed to determine the As, Cd, and Cr levels in three P fertilizers with contrasting PTE levels. It also investigated the accumulation and impacts of these elements in soil and relevant crops (potatoes, tobacco, rice) grown in tropical soil with and without liming. It also investigated the Cd-Se interaction and metabolic adjustments to minimize the plant physiology disturbance due to Cd uptake. A diverse array of sensitive techniques for trace elements determination were used to reveal the highest level of Cd of MAP 3. MAP 3 loaded the highest amounts of this element to the soil matrix and solution, plant shoots, and xylem sap, contrasting with results for MAP 1. The higher level of Cd in MAP 3 reduced Mn and Zn levels in plant shoots for potatoes and tobacco, while inducing an increase of antioxidant enzymes and sugars in rice. Acidic soils increased Cd concentrations in soil and plants decreased plant growth, yield, and sugar content, and induced metabolic adjustments related to antioxidant enzymes and proline. Among crops, rice had a lower Cd translocation compared to potato and tobacco, and a higher tolerance to acidic pH. Regarding Se, this element was efficient in increasing root growth, improving photosynthetic performance, stimulating S/Se metabolism compounds, and significantly increasing the content of S, Mo, and Fe, drastically reduced by Cd stress.

MEMBROS DA BANCA:
Externo à Instituição - CYNTHIA DE OLIVEIRA - UFLA (Membro)
Externo à Instituição - JOSE LAVRES JUNIOR - USP (Membro)
Externo à Instituição - FERNANDO CESAR BACHIEGA ZAMBROSI - IAC (Suplente)
Externo ao Programa - GUILHERME LOPES - DCS/ESAL (Membro)
Interno - EDUARDO GUSMÃO PEREIRA - UFV (Suplente)
Interno - PAULO EDUARDO RIBEIRO MARCHIORI (Membro)
Presidente - LUIZ ROBERTO GUIMARAES GUILHERME (Membro)