Published Date
November 2014, Vol.209(11):674–685, doi:10.1016/j.flora.2014.08.012
Title
Seed structure and germination in buriti (Mauritia flexuosa), the Swamp palm
Received 12 March 2014. Revised 15 August 2014. Accepted 25 August 2014. Available online 30 September 2014. Edited by Shahin Zarre
Highlights
Highlights
- •Seeds of M. flexuosa show structural characteristics related to recalcitrance.
- •Seeds and seedlings of M. flexuosa are adapted to swampy environments.
- •Dormancy and recalcitrance are crucial to the reproductive success of M. flexuosa.
Abstract
Associations of recalcitrance and dormancy are rare, and little information is available concerning the structure of seeds demonstrating this type of behavior or their ecological implications. Mauritia flexuosa is a palm tree associated with swampy environments in the Amazon rainforest and areas of Cerrado (neotropical savanna), the latter biome having marked climatic seasonality. We describe the structures and physiological aspects of the seeds and seedlings of this species to examine its adaptations to swampy environments and its germination control mechanisms, as well as the relationship between recalcitrance and dormancy in terms of reproductive success. Morphoanatomy and histochemistry of the seeds and seedlings were evaluated using standard methodologies, and the effects of temperature and operculum removal on germination were investigated. Differentiated tracheal elements in the embryo are associated with recalcitrance, and presence of numerous stomata on the embryo and the abundance of secondary metabolite compounds in the seedling indicate their adaptations to swampy environments. The inability of the embryo to overcome the resistance of the adjacent tissues determines dormancy of the physiological type, thus the removal of the operculum is an efficient method for promoting propagation. Cellular elongation in the cotyledon promotes seedling protrusion. Mobilization of endosperm reserves is achieved by symplastic flux and is associated with overcoming of dormancy by weakening the tissues adjacent to the embryo. The association between recalcitrance, which favors adaptation to swampy environments, and dormancy, which favors dispersal, is crucial for the reproductive success of this species and its broad geographical distribution.
Keywords
- Arecaceae
- Seed anatomy
- Swampy environments
- Cotyledonary petiole
- Haustorium
- Operculum
- ⁎ Corresponding author. Tel.: +55 38 3229 8154; fax: +55 38 3229 8180.
For further details log on website :
http://www.sciencedirect.com/science/article/pii/S0367253014001212
http://www.sciencedirect.com/science/article/pii/S0367253014001212
No comments:
Post a Comment