Abstract:
PREMISE:Although hybridization has played an important role in the evolution of many plant species, phylogenetic reconstructions that include hybridizing lineages have been historically constrained by the available models and data. Restriction-site-associated DNA sequencing (RADseq) has been a popular sequencing technique for the reconstruction of hybridization in the next-generation sequencing era. However, the utility of RADseq for the reconstruction of complex evolutionary networks has not been thoroughly investigated. Conflicting phylogenetic relationships in the genus Medicago have been mainly attributed to hybridization, but the specific hybrid origins of taxa have not been yet clarified. METHODS:We obtained new molecular data from diploid species of Medicago section Medicago using single-digest RADseq to reconstruct evolutionary networks from gene trees, an approach that is computationally tractable with data sets that include several species and complex hybridization patterns. RESULTS:Our analyses revealed that assembly filters to exclusively select a small set of loci with high phylogenetic information led to the most-divergent network topologies. Conversely, alternative clustering thresholds or filters on the number of samples per locus had a lower impact on networks. A strong hybridization signal was detected for M. carstiensis and M. cretacea, while signals were less clear for M. rugosa, M. rhodopea, M. suffruticosa, M. marina, M. scutellata, and M. sativa. CONCLUSIONS:Complex network reconstructions from RADseq gene trees were not robust under variations of the assembly parameters and filters. But when the most-divergent networks were discarded, all remaining analyses consistently supported a hybrid origin for M. carstiensis and M. cretacea.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Blanco-Pastor JL,Bertrand YJK,Liberal IM,Wei Y,Brummer EC,Pfeil BEdoi
10.1002/ajb2.1352subject
Has Abstractpub_date
2019-09-01 00:00:00pages
1219-1228issue
9eissn
0002-9122issn
1537-2197journal_volume
106pub_type
杂志文章abstract:PREMISE OF THE STUDY:Anatomical and morphological features of Satanocrater were studied to test hypotheses of xeric adaptations in the genus, which is endemic to arid tropical Africa. These features, together with molecular data, were used to test the phylogenetic placement of Satanocrater within the large plant family...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100354
更新日期:2012-06-01 00:00:00
abstract::Isozymatic data taken from 67 Guatemalan collections of maize were subjected to numerical taxonomic analyses to elucidate systematic relationships among the 19 maize races and subraces described for Guatemala by Wellhausen et al. As with Bolivian and Mexican races, isozymatic variation in Guatemalan maize was strongly...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/j.1537-2197.1990.tb13547.x
更新日期:1990-02-01 00:00:00
abstract::The possible pathways of origin of two recently arisen introgressant forms of Senecio vulgaris (i.e., var. hibernicus and York radiate groundsel) were investigated in experimental crosses between tetraploid S. vulgaris var. vulgaris and the normally diploid S. squalidus. Comparison of the morphology of synthesized hyb...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-08-01 00:00:00
abstract::The taxonomic richness of seed plants at different taxonomic levels was compared between temperate East Asia and North America at both continental and semi-continental scales. In each comparison, land area and latitude range were adjusted to a comparable level between the two continental regions. East Asia is signific...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.11.1818
更新日期:2002-11-01 00:00:00
abstract:UNLABELLED:• PREMISE OF THE STUDY:Two ovulate conifer cones, one of which is attached terminally to a short leafy shoot, reveal the presence of a new species of Hughmillerites in the Early Cretaceous Apple Bay flora of Vancouver Island, British Columbia, Canada. This ancient conifer expands the diversity of Cupressace...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400369
更新日期:2014-12-01 00:00:00
abstract:PREMISE OF THE STUDY:Evolutionary and biogeographic history, including past environmental change and diversification processes, are likely to have influenced the expansion, migration, and extinction of populations, creating evolutionary legacy effects that influence regional species pools and the composition of communi...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1049
更新日期:2018-03-01 00:00:00
abstract:PREMISE OF THE STUDY:During the interactions between a parasitic plant and its host, the parasite affects its host morphologically, anatomically, and physiologically, yet there has been little focus on the effect of hosts on the parasite. Here, the functional interactions between the hemiparasitic mistletoe Psittacanth...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600166
更新日期:2016-06-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Fungal plant pathogens exert much of their effect on plant cells through alterations in the host cell walls. However, obtaining biochemical proof for this change is difficult because of the relatively small number of cells that are affected by the pathogen relative to the bulk of host ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000099
更新日期:2010-12-01 00:00:00
abstract:PREMISE OF THE STUDY:Little is known about the effect of environmental conditions on seed dormancy break at the community level or how it could be affected by climate change. This study tested the effects of storage conditions on germination of 489 species from high-elevation natural grasslands on the Tibet Plateau. M...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000043
更新日期:2011-01-01 00:00:00
abstract:PREMISE OF THE STUDY:The evolutionary shift from radial to bilateral symmetry in flowers is generally associated with the evolution of low flower-size variation. This phenomenon supports the hypothesis that the lower size variation in bilateral flowers can be attributed to low pollinator diversity. In this study, we pr...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500371
更新日期:2015-12-01 00:00:00
abstract:PREMISE OF THE STUDY:Bio-ontologies are essential tools for accessing and analyzing the rapidly growing pool of plant genomic and phenomic data. Ontologies provide structured vocabularies to support consistent aggregation of data and a semantic framework for automated analyses and reasoning. They are a key component of...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200222
更新日期:2012-08-01 00:00:00
abstract::The desert moss Syntrichia caninervis exhibits one of the most skewed sex ratios in the plant kingdom, with female individuals far outnumbering male individuals (exceeding 14♀:1♂). The "cost of sex hypothesis" derives from allocational theory and predicts that the sex which is most expensive should be the rarer sex. T...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-11-01 00:00:00
abstract:PREMISE OF THE STUDY:The ecological and evolutionary significance of natural epigenetic variation (i.e., not based on DNA sequence variants) variation will depend critically on whether epigenetic states are transmitted from parents to offspring, but little is known on epigenetic inheritance in nonmodel plants. METHODS...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1074
更新日期:2018-04-01 00:00:00
abstract::In plants, polyploidy has been a significant evolutionary force on both recent and ancient time scales. In 1950, Ownbey reported two newly formed Tragopogon allopolyploids in the northwestern United States. We have made the first synthetic lines of T. mirus and T. miscellus using T. dubius, T. porrifolius, and T. prat...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800299
更新日期:2009-05-01 00:00:00
abstract:PREMISE OF THE STUDY:Fossilized seeds similar to Cissus (Vitaceae) have been recognized from the Miocene of Kenya, though some were previously assigned to the Menispermaceae. We undertook a comparative survey of extant African Cissus seeds to identify the fossils and consider their implications for the evolution and bi...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600177
更新日期:2016-09-01 00:00:00
abstract::Welwitschiaceae, a family in the Gnetales, is known today from only one extant species, Welwitschia mirabilis. This species is distributed in the Namibian desert, along the western coast of southern Africa, about 10 km inland from the coast. Very little is known about the fossil record of this family. Lower Cretaceous...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.8.1294
更新日期:2005-08-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Polyploid speciation has been important in plant evolution. However, the conditions that favor the origination and persistence of polyploids are still not well understood. Here, we examine origins of 16 polyploid species in Mentzelia section Trachyphytum. • METHODS:We used phylogeny r...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900388
更新日期:2010-09-01 00:00:00
abstract:PREMISE OF THE STUDY:Previous studies have shown that polyploidy has pronounced effects on photosynthesis. Most of these studies have focused on synthetic or recently formed autopolyploids, and comparatively little is known about the integrated effects of natural allopolyploidy, which involves hybridity and genome doub...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100465
更新日期:2012-01-01 00:00:00
abstract::The degree to which plants self-fertilize may impact their potential for genetic adaptation. Given that the mating system influences genetic processes within and among populations, the mating system could limit or promote local adaptation. I conducted a literature survey of published reciprocal transplant experiments ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900224
更新日期:2010-02-01 00:00:00
abstract:PREMISE OF THE STUDY:In animal-pollinated plants, autonomous selfing may provide reproductive assurance when pollinators or reproductive partners are limited. Under such circumstances, the contribution of pollinator-mediated seed set to total seed production also may be more variable compared with situations in which p...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100154
更新日期:2011-11-01 00:00:00
abstract::Phylogenetic relationships and biogeography of the genus Cerastium were studied using sequences of three noncoding plastid DNA regions (trnL intron, trnL-trnF spacer, and psbA-trnH spacer). A total of 57 Cerastium taxa was analyzed using two species of the putative sister genus Stellaria as outgroups. Maximum parsimon...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.6.943
更新日期:2004-06-01 00:00:00
abstract::Herbivore damage is known to cause the premature loss of mature leaves. However, the effects of herbivory on abscission during the early stages of leaf development remain unexplored, even though herbivores frequently prefer unlignified, immature leaves. In a field experiment, we removed 50% of the tissue from leaves a...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-11-01 00:00:00
abstract::Very little is known regarding how repetitive elements evolve inpolyploid organisms. Here we address this subject by fluorescent insitu hybridization (FISH) of 20 interspersed repetitive elements tometaphase chromosomes of the cotton AD-genome tetraploid Gossypiumhirsutum and its putative A- and D-genome diploid ances...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-10-01 00:00:00
abstract::We present here the first molecular phylogeny of tribe Diseae (Orchidoideae: Orchidaceae). Nuclear ribosomal ITS1, 5.8S rDNA, and ITS2 sequences were compared for 30 Diseae, 20 Orchideae, and four Cranichideae and Diurideae outgroups. ITS - rDNA sequences exhibited a transition:transversion ratio of 1.3 and extensive ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-06-01 00:00:00
abstract::The specific shape of the relationship between plant diversity and productivity and the causal mechanism(s) behind the observed pattern(s) are still highly debated. Recent advances suggest that the relationship depends on several environmental variables and may change with the observational scale. In this study, a mul...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.1.79
更新日期:2007-01-01 00:00:00
abstract:PREMISE OF THE STUDY:Miscanthus, a nonfood plant with high potential as a biofuel, has been used in Europe and the United States. The selection of a cultivar with high biomass, photosynthetic efficiency, and stress resistance from wild populations has become an important issue. New genic microsatellite markers will aid...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100071
更新日期:2011-08-01 00:00:00
abstract::Oxalate crystals are very common in angiosperms, but few descriptions of their macropattern (crystal types, their tissue distribution, and development) exist. Because unusually large prismatic crystals and druses, are known from pomegranate, we traced the development of crystal macropattern in various-aged leaf sample...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.12.1935
更新日期:2005-12-01 00:00:00
abstract:PREMISE:Despite the efforts to understand the processes that shape neotropical biodiversity, the complexity of certain biomes, such as the Atlantic Forest (AF), prevents the generalization of patterns. Initially, ecological niche modeling (ENM), with phylogeographic studies, identified past stable areas in the central ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1317
更新日期:2019-07-01 00:00:00
abstract:PREMISE OF THE STUDY:Male-biased herbivory in dioecious species is expected as a consequence of selection for increased resistance (reduced attack) in the sex with higher reproductive costs-females. Empirical support of this prediction is taxonomically restricted and fraught with exceptions. Phenological changes in res...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200603
更新日期:2013-02-01 00:00:00
abstract:PREMISE:The Eocene-Oligocene transition (EOT; 34-33 Ma) was marked by global cooling and increased seasonality and aridity, leading to a shift in North American floras from subtropical forests to deciduous hardwood forests similar to today. This shift is well documented taxonomically and biogeographically, but its ecol...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1580
更新日期:2020-12-01 00:00:00