TY - JOUR
T1 - Placing the woody tropical genera of Polygonaceae
T2 - A hypothesis of character evolution and phylogeny
AU - Burke, Janelle M.
AU - Sanchez, Adriana
AU - Kron, Kathleen
AU - Luckow, Melissa
N1 - Copyright:
Copyright 2010 Elsevier B.V., All rights reserved.
PY - 2010
Y1 - 2010
N2 - Premise of the study: Taxonomic groups have often been recognized on the basis of geographic distinctions rather than accurately representing evolutionary relationships. This has been particularly true for temperate and tropical members from the same family. Polygonaceae exemplifies this problem, wherein the woody tropical genera were segregated from temperate members of the family and placed in the subfamily Polygonoideae as two tribes: Triplarideae and Coccolobeae. Modern phylogenetic studies, especially when inferred from many lines of evidence, can elucidate more probable hypotheses of relationships. This study builds on previous work in the family and aims to test the traditional classification of the tropical woody taxa, which have been understudied and undersampled compared to their temperate relatives. Methods: A phylogenetic study was undertaken with expanded sampling of the tropical genera with data from five plastid markers (psbA-trnH, psaI-accD, matK, ndhF, and rbcL), nuclear ribosomal DNA (ITS) and morphology. Key results: Results support the placement of nine of 12 genera of the Triplarideae and Coccolobeae within Eriogonoideae, in which these genera form a paraphyletic assemblage giving rise to Eriogoneae. The remaining woody tropical genera excluded from Eriogonoideae occur in the paleotropics. Conclusions: Traditional characters used to delimit Coccolobeae and Triplarideae are not useful for defining monophyletic groups. The six-tepal condition is derived from the five-tepal condition, and unisexual flowers have arisen multiple times in different sexual systems. Ruminate endosperm has arisen multiple times in the family, suggesting this character is highly plastic.
AB - Premise of the study: Taxonomic groups have often been recognized on the basis of geographic distinctions rather than accurately representing evolutionary relationships. This has been particularly true for temperate and tropical members from the same family. Polygonaceae exemplifies this problem, wherein the woody tropical genera were segregated from temperate members of the family and placed in the subfamily Polygonoideae as two tribes: Triplarideae and Coccolobeae. Modern phylogenetic studies, especially when inferred from many lines of evidence, can elucidate more probable hypotheses of relationships. This study builds on previous work in the family and aims to test the traditional classification of the tropical woody taxa, which have been understudied and undersampled compared to their temperate relatives. Methods: A phylogenetic study was undertaken with expanded sampling of the tropical genera with data from five plastid markers (psbA-trnH, psaI-accD, matK, ndhF, and rbcL), nuclear ribosomal DNA (ITS) and morphology. Key results: Results support the placement of nine of 12 genera of the Triplarideae and Coccolobeae within Eriogonoideae, in which these genera form a paraphyletic assemblage giving rise to Eriogoneae. The remaining woody tropical genera excluded from Eriogonoideae occur in the paleotropics. Conclusions: Traditional characters used to delimit Coccolobeae and Triplarideae are not useful for defining monophyletic groups. The six-tepal condition is derived from the five-tepal condition, and unisexual flowers have arisen multiple times in different sexual systems. Ruminate endosperm has arisen multiple times in the family, suggesting this character is highly plastic.
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U2 - 10.3732/ajb.1000022
DO - 10.3732/ajb.1000022
M3 - Article
AN - SCOPUS:77955991097
SN - 0002-9122
VL - 97
SP - 1377
EP - 1390
JO - American Journal of Botany
JF - American Journal of Botany
IS - 8
ER -