In the last decade, efforts to reconstruct suprageneric phylogeny of the Cyperaceae have intensified. We present an analysis of 262 taxa representing 93 genera in 15 tribes, sequenced for the plastid rbcL and trnL-F (intron and intergenic spacer). Cyperaceae are monophyletic and resolved into two clades, here recognised as Mapanioideae and Cyperoideae, and the overall topology is similar to results from previous studies. Within Cyperoideae, Trilepideae are sister to rest of taxa whereas Cryptangieae, Bisboeckelerieae and Sclerieae are resolved within Schoeneae. Cladium and Rhynchospora (and Pleurostachys) are resolved into clades sister to the rest of Schoeneae, lending support to the recognition of these taxa in separate tribes. However, we retain these taxa in Schoeneae pending broader sampling of the group. The phylogenetic position of 40 species in 21 genera is presented in this study for the first time, elucidating their position in Abildgaardieae (Trachystylis), Cryptangieae (Didymiandrum, Exochogyne), Cypereae (Androtrichum, Volkiella), Eleocharideae (Chillania), and Schoeneae (Calyptrocarya, Morelotia). More sampling effort (more taxa and the use of more rapidly evolving markers) is needed to resolve relationships in Fuireneae and Schoeneae.
No abstract
Since the Monocots II meeting in 1998, significant new data have been published that enhance our systematic knowledge of Cyperaceae. Phylogenetic studies in the family have also progressed steadily. For this study, a parsimony analysis was carried out using all rbcL sequences currently available for Cyperaceae, including data for two new genera. One of the four subfamilies (Caricoideae) and seven of the 14 tribes (Bisboeckelereae, Cariceae, Cryptangieae, Dulichieae, Eleocharideae, Sclerieae, Trilepideae) are monophyletic. Subfamily Mapanioideae and tribe Chrysitricheae are monophyletic if, as the evidence suggests, Hellmuthia is considered a member of Cypereae. Some other features of our analysis include: well-supported Trilepideae and Sclerieae-Bisboeckelereae clades; a possible close relationship between Cryptangieae and Schoeneae; polyphyletic tribes Schoeneae and Scirpeae; the occurrence of Cariceae within the Dulichieae-Scirpeae clade, and a strongly supported clade, representing Cyperus and allied genera in Cypereae, sister to a poorly supported Ficinia-HellmuthiaIsolepis-Scirpoides clade. Such patterns are consistent with other studies based on DNA sequence data. One outcome may be that only two subfamilies, Mapanioideae and Cyperoideae, are recognized. Much further work is needed, with efforts carefully coordinated among researchers. The work should focus on obtaining morphological and molecular data for all genera in the family.
Using a DNA-based tree as the framework, the homology of key taxonomic characters in tribe Cypereae (900 species in 19 genera, the largest of which is Cyperus) is assessed and revisit the question of generic circumscription. Plastid DNA (rbcL gene, rps16 intron, trnL intron and trnL-F intergenic spacer) sequence matrix for 50 species in 19 genera of Cypereae is analysed using the maximum parsimony algorithm of PAUP. Two major groups are observed: the Ficinia and Cyperus clades. The Ficinia clade includes taxa with a center of diversity in the Cape Floristic Region of South Africa. These are predominantly perennial herbs (with exception of Isolepis, which is predominantly annual) having non-Kranz (C 3 ) anatomy and spirally arranged glumes. Species of the Cyperus clade have a predominatly distichous glume arrangement and Kranz anatomy which is either absent (C 3 ) or present (C 4 ). Cyperus is the core genus in the Cyperus clade, in which 13 additional segregate genera are embedded. These segregate genera differ from typical Cyperus in one or more of a few gross morphological characters. There are no unambiguous characters separating C 3 and C 4 Cyperus species. The circumscription of Cypereae is broadened to include all taxa with a Cyperus-type embryo and perianth segments. Three taxa possessing perianth segments, namely Hellmuthia membranacea, Scirpus falsus and S. ficinioides, are supported to be closer to Cyperus than to Scirpus.
The genus Peperomia is one of the largest genera of basal angiosperms, comprising about 1500-1700 pantropically distributed species. The currently accepted infrageneric classification divides Peperomia into nine subgenera and seven sections. This classification is based on some 200 species, primarily using fruit morphology. The monophyly of these infrageneric taxa has never been tested and molecular phylogenetic studies of a representative sampling within Peperomia do not exist. This paper provides the first molecular phylogeny for the genus Peperomia. Monophyletic clades within Peperomia are identified and previously used morphological characters are critically reviewed. We show that the importance of some morphological characters has been overestimated and that some of these characters presumably have evolved several times independently. Only one previously described subgenus has been confirmed to be monophyletic.
Maximum likelihood and Bayesian analyses of nrDNA (ETS1f) and plastid DNA (rpl32‐trnL, trnH‐psbA) sequence data are presented for ‘C3Cyperus’ (Cyperaceae). The term ‘C3Cyperus’ indicates all species of Cyperus s.l. that use C3 photosynthesis linked with eucyperoid vegetative anatomy. Sampling comprises 77 specimens of 61 different taxa, representing nearly all previously recognized subdivisions of C3Cyperus and the segregate genera Courtoisina, Kyllingiella and Oxycaryum. According to our results, the Cyperus clade is divided in six well‐supported clades. The first of these clades (clade 1) forms three subclades largely corresponding to Cyperus sections Haspani, Incurvi and Diffusi. Clade 2 comprises the entirely New World C. section Luzuloidei sensu Denton (1978). Clade 3 is a highly diverse clade including two subclades: clade 3a, C. sections Pseudanosporum and Anosporum plus the segregate genera Courtoisina and Oxycaryum; and clade 3b, C. section Fusci. Clade 4 corresponds to C. section Alternifolii and clade 5 to C. section Leucocephali plus the segregate genus Kyllingiella. The sixth clade is a well‐supported monophyletic clade encompassing all C4Cyperus s.l. species (‘C4Cyperus’). This study establishes a phylogenetic framework for future studies. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167, 19–46.
The AFLP technique was used to assess the genetic relationships among the cultivated papaya ( Carica papaya L.) and related species native to Ecuador. Genetic distances based on AFLP data were estimated for 95 accessions belonging to three genera including C. papaya, at least eight Vasconcella species and two Jacaratia species. Cluster analysis using different methods and principal co-ordinate analysis (PCO), based on the AFLP data from 496 polymorphic bands generated with five primer combinations, was performed. The resulted grouping of accessions of each species corresponds largely with their taxonomic classifications and were found to be consistent with other studies based on RAPD, isozyme and cpDNA data. The AFLP analysis supports the recent rehabilitation of the Vasconcella group as a genus; until recently Vasconcella was considered as a section within the genus Carica. Both cluster and PCO analysis clearly separated the species of the three genera and illustrated the large genetic distance between C. papaya accessions and the Vasconcella group. The specific clustering of the highly diverse group of Vasconcella x heilbornii accessions also suggests that these genotypes may be the result of bi-directional introgression events between Vasconcella stipulata and Vasconcella cundinamarcensis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.