Banca de DEFESA: SANIELY MARIA BEZERRA DE MELO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : SANIELY MARIA BEZERRA DE MELO
DATA : 23/02/2017
HORA: 14:00
LOCAL: Sala de Seminários 1 (SS1) DBG CB
TÍTULO:

Physiological and oxidative alterations during storage of Moringa oleifera Lam seeds

PALAVRAS-CHAVES:

Antioxidant enzymes; Ascorbate; Hydrogen peroxide; Primary root atrophy; Protein carbonylation; Seed deterioration

PÁGINAS: 44
GRANDE ÁREA: Ciências Agrárias
ÁREA: Recursos Florestais e Engenharia Florestal
SUBÁREA: Silvicultura
ESPECIALIDADE: Sementes Florestais
RESUMO:

Oxidative damage plays a central role in seed deterioration during storage. In this sense, the current work aimed at characterizing seed viability and vigour as well as oxidative damage and protection through the storage of Moringa oleifera Lam. (moringa) seeds. Seed samples were transferred to semipermeable plastic bags and stored in a growth chamber (27 ± 2ºC and 65% RH) and in a refrigerator (4 ± 2ºC and 25% RH) for 18 months. Harvests were carried out after seed processing and every 3 months in the course of storage. Water content, germination percentage, germination speed index (GSI), abnormal seedling percentage, K⁺ leakage, H₂O₂ content, lipid peroxidation, protein carbonylation, reduced ascorbate (AsA) content, in addition to the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), phenol peroxidase (POX) and catalase (CAT) were evaluated. The decrease of germination percentage and GSI associated with the increase of K⁺ leakage and abnormal seedling percentage was more intense in the seeds maintained in the growth chamber than in those maintained under refrigeration during 18 months. Lipid peroxidation remained unchanged, H₂O₂ content and POX activity decreased while protein carbonylation, AsA content and SOD, APX, and CAT activities increased over time, regardless of the storage environment. Therefore, viability and vigour of moringa seeds were better preserved under refrigeration at low RH for a maximum period of 12 months. Quality loss beyond this period might not be attributed to H₂O₂ accumulation and lipid peroxidation, but it could involve protein oxidation. The preservation of AsA content and SOD, APX and CAT activities seems insufficient to maintain the viability and vigour of moringa seeds after 12 months of storage.

MEMBROS DA BANCA:
Presidente - 1228866 - EDUARDO LUIZ VOIGT
Interno - 1721230 - MAURO VASCONCELOS PACHECO
Externo à Instituição - THIAGO BARROS GALVAO - NENHUMA