| Autor: |
Staedler, Yannick M., Weston, Peter H., Endress, Peter K. |
| Předmět: |
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| Zdroj: |
International Journal of Plant Sciences; Jan2009, Vol. 170 Issue 1, p21-41, 21p, 1 Black and White Photograph, 15 Diagrams |
| Abstrakt: |
Calycanthaceae, sister to all other Laurales, are the most distinct family of the order in their gynoeciumstructure (lateral placentation, presence of two ovules). Gynoeciumstructure was studied in a representative of each genus of Calycanthaceae and gynoecium development in a representative of each of the two subfamilies (Calycanthoideae andIdiospermoideae).Newly foundshared features are postgenital coherence between the free carpels (extragynoecial compitum), abortion of the upper of the two ovules, and lobation of the outer integument.Differences in reproductive structures between the two subfamilies are reviewed. Newly found differences include carpel primordium shape, contribution of the outer integument tomicropyle formation, epidermis differentiation of the rim of the integuments, and mode of formation of the compitum. Unexpectedly, at anthesis, ovary and ovules of Idiospermum are not larger than those ofCalycanthoideae, despite the conspicuous difference in fruit. The identity of ''staminodes'' (sterile organs between stamens and carpels) is discussed. Sterile carpel-like structures (carpellodes) are documented in Idiospermum. The lateral ovule position in Calycanthaceae is correlatedwith a different development of carpel closure as compared with core Laurales, which exhibit median ovule position. Gynoecium morphology of fossil Calycanthaceae and its implications for gynoecium evolution in Calycanthaceae and Laurales are discussed. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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