Banca de DEFESA: BRUNO SILVA GUIRRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : BRUNO SILVA GUIRRA
DATE: 29/05/2020
TIME: 14:00
LOCAL: On Line
TITLE:

BIOCHEMICAL AND PHYSIOLOGICAL CHANGES IN SEEDS OF Combretum leprosum Mart. DURING STORAGE

KEY WORDS:

combretaceae, forest seeds, seed quality, seed metabolic responses, viability and vigor.

PAGES: 35
BIG AREA: Ciências Agrárias
AREA: Recursos Florestais e Engenharia Florestal
SUBÁREA: Silvicultura
SPECIALTY: Sementes Florestais
SUMMARY:

The mofumbo (Combretum leprosum Mart.), Family Combretaceae, has exclusive distribution in South America. It is a species of great forest importance for the whole of Brazil and, mainly, for the Caatinga ecosystem. It presents several potentialities, in addition to contributing significantly to the conservation and improvement of soil quality in the recovery process of degraded areas and ecological succession in dry forests. Despite its importance, there are still no basic studies on the types of storage for maintaining the viability and vigor of seeds for a certain period. Thus, the objective was to evaluate the physiological and biochemical changes of C. leprosum seeds under different storage conditions. The completely randomized experimental design, in a factorial scheme (2 x 2 x 7), with two storage conditions x two forms of seed processing x seven storage periods (0; 60; 120; 180; 240; 300 and 360 days). The data of the quantitative factors were subjected to analysis of variance and the means compared by the Tukey test at 5% probability. For storage periods, regression analysis was performed. After collecting the fruits of C. leprosum, half of the lot was processed manually, the external protection that covered the seed was removed and the other part was kept the diaspores. For storage, all bare seeds and those protected with diaspores were packed in kraft paper bags and kept in two storage conditions: natural environment and air-conditioned chamber (10 ± 1 ° C; 53 ± 7% relative humidity). At the beginning and at 60-day intervals, for 360 days, the seeds were analyzed for the determination of water content, physiological quality (germination, germination speed index, length and dry mass of seedlings) and biochemistry (neutral lipids, sugars total and reducing agents, total free amino acids, starch and lipid peroxidation). The physiological variables expressed better results in the condition of natural environment, regardless of the way the seed is processed. Esse ambiente também proporcionou menor degradação da reserva de lipídios. Regarding starch, there was hydrolysis of this polysaccharide throughout the storage period. Finally, it was found that the deterioration of seeds after 180 days of storage is associated with the attack of reducing sugars to amino acids, which led to the Maillard reaction and resulted in reduced viability and vigor.

BANKING MEMBERS:
Interno - 1721230 - MAURO VASCONCELOS PACHECO
Interno - 270.392.004-06 - SALVADOR BARROS TORRES - UFC
Externo à Instituição - ALEK SANDRO DUTRA - UFC