Abstract Detail



Systematics

Grant, Kirstie [1], Burke, Janelle [2].

A proposed phylogenetic & taxonomic reclassification of the collective Rumex genus.

The genus Rumex is a unique member of the Polygonaceae (Buckwheat) family of plants. A source of intrigue for Rumex lies in the diversity of the sexual systems associated with the subgenera, species, and subspecies within this genus. Four currently recognized subgenera, some 200 species, and a number of subspecies comprise the collective Rumex genus. These exhibit monoecious, dioecious, hermaphroditic, gynodioecious and polygamous sexual systems. Moreover, some of the dioecious species contain sex chromosomes, a phenomenon that occurs in roughly 1% of angiosperms. Apart from the confirmed morphological and phytogeographical distinctions, two of the four subgenera, Acetosa and Acetosella, are distinctive in their mode of sex-determining mechanisms, sex-chromosome systems, and resulting sexual systems.We reconstructed a phylogeny to test the evolution of different sexual systems and sex chromosome systems within Rumex. To date, we have observed three chloroplast molecular markers, rbcL, trnH-psbA, 3’trnLUAAF-trnFGAA, and increased taxon sampling compared to previous work. The phylogeny resolves two clades in Rumex: Rumex subgenus Rumex, sister to a clade containing the rest of the subgenera, plus the genus Emex. Furthermore, the species with sex chromosomes are resolved in two different clades with different sex chromosome systems. These results suggest that the species with divergent sexual systems are more closely related to each other, than to other species comprising the rest of the genus.


1 - 2251 Sherman Ave. NW, Washington, DC, 20001, United States
2 - Howard University, Biology, 415 College St. NW, Washington, DC, 20001, USA

Keywords:
Rumex
Sexual systems
phylogeny.

Presentation Type: Poster
Number: PSY005
Abstract ID:289
Candidate for Awards:None


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