Banca de DEFESA: PRISCILA PEREIRA DA SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : PRISCILA PEREIRA DA SILVA
DATE: 26/02/2024
TIME: 09:00
LOCAL: Sala virtual do Google Meet
TITLE:

Water memory involves changes in reserve mobilization during seed germination in the Caatinga native species Cenostigma pyramilade

KEY WORDS:

Discontinuous hydration, legume tree, seed imbibition, soluble sugars, starch

PAGES: 55
BIG AREA: Ciências Agrárias
AREA: Recursos Florestais e Engenharia Florestal
SUBÁREA: Silvicultura
SPECIALTY: Sementes Florestais
SUMMARY:

Given that water availability plays a central role in seed germination and is a limiting resource in arid and semi-arid environments, a series of experiments were performed to characterize hydration kinetics, reserve mobilization, and water memory in seeds of Cenostigma pyramidale, a tree legume native to the Caatinga. Germination tests were carried out using the paper roll technique, and the contents of water, reserves, and metabolites were assessed during seed hydration until radicle protrusion. Hydration kinetics during germination fitted into the triphasic pattern, although imbibition began slowly and became fast during phase I. Since water uptake by the testa was slower than that by the embryo during phase I, the testa was clearly involved in the regulation of seed imbibition. In seeds germinated under continuous hydration, oils were mobilized in the cotyledons during phases I and III, and non-reducing sugars in the embryonic axis supported phase II. Seeds exposed to a hydration-dehydration cycle revealed changes in the germination process when they were rehydrated. Water uptake became faster by the intact seed and its different parts (testa, embryonic axis, and cotyledons). Also, seeds germinated under discontinuous hydration retained oils but mobilized carbohydrates in the cotyledons. These findings can contribute to understanding the mechanisms used by C. pyramidale seeds to respond to discontinuous hydration and can be applied to protocols for seedling production.

COMMITTEE MEMBERS:
Presidente - 1228866 - EDUARDO LUIZ VOIGT
Externa ao Programa - 1516627 - JULIANA ESPADA LICHSTON - UFRNExterna à Instituição - CLÁUDIA ULISSES DE CARVALHO SILVA