Contribuição para o conhecimento da capacidade e vigor germinativos de sementes...

• Author(s): Marques, Filipe Alexandre de Andrade
• Date: 2014
• Persistent ID: http://hdl.handle.net/10400.5/6794
• Origin: Repositório da UTL
• Subject(s): Acacia longifolia; Acacia dealbata; germination; provenances; seed propagation; chlorophyll fluorescence
• Document Type: Master Thesis
• Language: Portuguese
• Advisor(s): Fabião, António Dorotea; Afonso, Marta Falcão

Description

Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia The aim of this study was to improve the knowledge on seed-coat dormancy and germination skills of Acacia, seeking to clarify key aspects relating to the efficiency of its expansion through seed propagation. The species, Acacia longifolia (provenance: Sintra) and A. dealbata (provenances: Fundão and Cabrum river valley), are considered two of the most invasive of its genus in Portugal. For both species two seed propagation tests were performed: one for pre-germination treatment and another for germination in nursery environment. In these trials, we determined the weight of seeds, the germination rate and the vigor index; hot water (90° C followed by 24 hour immersion) was used to break the seed-coat dormancy. In the experiment performed in the nursery the two species were also compared for the rate of mortality, and for vitality through the determination of chlorophyll fluorescence. The results indicated that Acacia longifolia has a higher fitness than A. dealbata to seed propagation. This capability was confirmed by a potential germination in chamber significantly higher than that of A. dealbata, by a higher germination rate in nursery and higher vitality of seedlings produced, measured by a post-germinative mortality rate significantly lower.