Abstract Detail

Reproductive Processes

Angulo, Juan [1], Burke, Janelle [2], Michelangeli, Fabian [3].

Characterizing a wide morphological spectrum of dioecy in neotropical Miconia (Melastomataceae).

Understanding plant reproductive systems is an important goal in plant biology, as a plant’s sexual system underlies and affects many patterns in evolution and ecology. Therefore, a thorough morphological characterization of sexual system in plant groups is needed, and yet, for many major groups we lack this basic information. I present an ongoing study of the first comprehensive documentation and floral character analysis of the reproductive systems within a diverse clade of Miconia (Melastomataceae) containing ~225 mostly Andean species, out of ca. 1900 in the genus. These neotropical plants are largely hermaphroditic, but dioecy, albeit rare, has already been reported for 37 species. Dioecy is a system defined by unisexual flowers on seperate staminate and pistillate individuals and has only been documented in Melastomataceae through species descriptions in this genus. Using herbarium specimens, we identified an additional 25 dioecious species, and assessed the wide morphological variation and peculiar patterns of disjunct geographic occurrence among the species. Floral morphology varies greatly across dioecious species: the gynoecium of staminate plants ranges from completely absent to differing vestigial forms of style and ovaries, while the androecium of pistillate plants is characterized by smaller stamens with collapsed anthers bearing no pollen. This striking variation of reproductive morphology raises intriguing questions about the geographic and phylogenetic origins of dioecy in Miconia, and is testament to the continued relevance of herbarium collections and research.

1 - New York Botanical Garden, 2900, Southern Boulevard, Bronx, NY, 10458, United States
2 - Howard University, Dept. Of Biology, 415 College St. NW, Just Hall 328, Washington, DC, 20059, United States
3 - The New York Botanical Garden, 2900 Southern Blvd, Bronx, NY, 10458, United States


Presentation Type: Oral Paper
Number: RP2005
Abstract ID:639
Candidate for Awards:None

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