Seed size influence on germination responses to light and temperature of seven pioneer tree species from the Central Amazon

Anais da Academia Brasileira de Ciências

Fabiana F. Aud²  Isolde D.k. Ferraz¹ 

[1] ,Instituto Nacional de Pesquisas da Amazônia Coordenação de Pesquisa em Ecologia Manaus AM ,Brasil

关键词: Alternating temperatures;    germinability;    mean germination time;    photoblastic germination;    secondary forests;    tropical trees;    Alternância de temperatura;    germinabilidade;    tempo médio de germinação;    germinação fotoblástica;    florestas secundárias;    árvores tropicais;   

DOI  :  10.1590/S0001-37652012000300018

来源: SciELO

【 摘 要 】

In Amazon secondary forests are dominated by pioneer species that typically produce large amounts of small and dormant seeds that are able to form a persistent soil seed bank. Seed dormancy in this group of species is overcome by environmental conditions found in open areas, such as high irradiation or alternating temperatures. Nevertheless, a variety of germination responses to environmental factors is known among pioneers; some of them may germinate in diffuse light or in darkness condition at constant temperature. Seed mass can be considered as one of the factors that promotes this variety. Regarding species with very small seeds, it seems that the trigger for germination is light and for larger seeds temperature alternation may be a more important stimulus. In this study we established a relationship between seed mass and germination response to light and alternating temperature for a group of seven woody pioneer species from the Amazon forest. We found that an increase in seed mass was followed by a decrease in the need for light and an increase in the tolerance to alternating temperatures. Understanding germination strategies may contribute with the knowledge of species coexistence in high diverse environments and also may assist those involved in forest management and restoration.

【 授权许可】

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