Banca de QUALIFICAÇÃO: BRUNO SILVA GUIRRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : BRUNO SILVA GUIRRA
DATE: 24/03/2020
TIME: 14:00
LOCAL: Laboratório de Análises de Sementes - LAS/UFERSA
TITLE:

BIOCHEMICAL AND PHYSIOLOGICAL RESPONSES OF Combretum leprosum Mart. DURING STORAGE

KEY WORDS:

forest seeds, seed quality, seed metabolic changes

PAGES: 45
BIG AREA: Ciências Agrárias
AREA: Recursos Florestais e Engenharia Florestal
SUBÁREA: Silvicultura
SPECIALTY: Sementes Florestais
SUMMARY:

The mofumbo (Combretum leprosum Mart.) Belonging to the Combretaceae family, with exclusive distribution in South America. It is a species of great forest importance for the whole of Brazil and, mainly, for the Caatinga biome, since it presents several potentialities, since medicinal purposes, in addition contributes significantly to conservation and improvement of soil quality in the process of recovery of degraded areas and succession in dry forests. Despite multiple uses, there are still no basic studies on the storage of its seeds. Thus, the objective was to evaluate the physiological and biochemical changes of C. leprosum according to the ways of maintaining the seed under different storage conditions. For that, all the naked seeds and the diaspores were packed in kraft paper bags and kept in two different conditions: condition of natural environment (26 ± 3 ° C; 55 ± 12% RH) and air-conditioned chamber (10 ± 1 ° C ; 53 ± 7% RH). Initially, and every 30 days, for 12 months, the seeds were analyzed for their physiological quality (determination of seed water content, seedling emergence, emergence speed index, seedling length and dry mass) and biochemistry ( neutral lipids, total and reducing sugars, total free amino acids, starch and, in addition, lipid peroxidation). The data of the quantitative factors for the four treatments were subjected to analysis of variance and the means compared by the Tukey test at 5% probability. For storage periods, regression analysis was performed, selecting the significant models (F> 0.05) with the best biological expression. For the variables of seedling emergence, emergence speed index and seedling dry mass, the natural condition provided better results. Regarding the variables of lipids and peroxidation, the seeds suffered degradation, regardless of the form of seed maintenance and storage condition. Until the sixth month there was an accumulation of soluble sugar content, followed by a reduction until the end of the storage time. For starch, there was a decline in the content of this polysaccharide in all treatments, throughout the storage period, with the least variation being found in bare seeds, when stored in a natural environment. Finally, there was an increase in the amino acid content during the entire storage period, in almost all treatments, with the exception of diaspores conditioned in air-conditioned environments. The seeds of C. leprosum, when stored in a natural environment, remain viable and with high quality for a period of twelve months, regardless of how the seed is maintained.

BANKING MEMBERS:
Presidente - 270.392.004-06 - SALVADOR BARROS TORRES - UFC
Externa à Instituição - CLARISSE PEREIRA BENEDITO - UFERSA
Externo à Instituição - EMANOELA PEREIRA DE PAIVA - UFERSA
Externo à Instituição - CAIO CESAR PEREIRA LEAL - IFRN