Abstract：
:Up to 22% of plant species are the result of breeding among species-hybridization-directly conflicting with the prediction that hybrids, compared to parental species, are intermediate in character and of low fitness and little consequence. Few studies, however, have compared the fitness of hybrids and parental species under field conditions. This study evaluates components of fitness in the field for naturally occurring hybrids of the shrub Kunzea, relative to the parental speciesKunzea rupestris. Hybrid plants did not differ from the parental species in the level of effective pollination. Thus, we found no support for Grant's model (Evolution: International Journal of Organic Evolution3: 82-97) of reduced fitness of hybrids via reduced pollination level (the intermediate hypothesis). Hybrids displayed variable fitness across the measured fitness components. Seed set levels for hybrids were structured among populations, suggesting genetic structuring for this fitness component at this scale. The response of hybrids to fire (a major selective force in the study system) was partly consistent with a resource trade-off model. Hybrids were large robust plants but most did not resprout after fire. Hence, the fitness of hybrids was complex. We developed a model for relative fitness to estimate fitness for species and hybrids with complex life histories.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Tierney DA,Wardle GMdoi
10.3732/ajb.95.2.146subject
Has Abstractpub_date
2008-02-01 00:00:00pages
146-55issue
2eissn
0002-9122issn
1537-2197pii
95/2/146journal_volume
95pub_type
杂志文章abstract：:Many plant species contain populations with more than one polyploid cytotype, but little is known of the mechanisms maintaining several cytotypes in a population. Andropogon gerardii cytotypes were compared to evaluate different models of autopolyploid cytotype coexistence. The enneaploid (90 chromosome, 9x) cytotype ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1999-07-01 00:00:00
abstract：:Megaspore and microspore massulae of Paleoazolla patagonica gen. et sp. nov. are described from the Upper Cretaceous of La Colonia Formation, Chubut Province, Argentina. The new fern possesses megaspore complexes with three to four glochidiate floats attached directly to the megaspore; a columella-like structure appea...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1999-08-01 00:00:00
abstract：:Cleistogamous capitula formed by Centaurea melitensis display a number of morphological and functional changes with respect to chasmogamous capitula that ensure self-fertilization. Because no studies have hitherto addressed the evolution of cleistogamy in Asteraceae, it was considered useful to ascertain whether these...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2000-07-01 00:00:00
abstract：PREMISE OF THE STUDY:Plant-herbivore networks are highly specialized in their interactions, yet they are highly variable with regard to the relative importance of specific host species for herbivores. How host species traits determine specialization and species strength in this antagonistic network is still an unanswer...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1600045
更新日期：2016-08-01 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：: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：:The origin of polyploid Bromus species of section Genea was investigated using molecular data. This group of annual species native from the Old-World is composed of three diploids, two tetraploids, one hexaploid, and one octoploid. Molecular cloning, sequencing, and phylogenetic analyses were performed on several acce...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.95.4.454
更新日期：2008-04-01 00:00:00
abstract：PREMISE OF THE STUDY:Herbivory can affect a plant's fitness in a variety of ways, including modifying the biotic interactions of the plant. In particular, when herbivory influences floral display, we hypothesize that pollinator visitation will be altered accordingly. Here we studied the indirect effects of feeding by t...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1500043
更新日期：2015-05-01 00:00:00
abstract：:Leaf habit correlates with multiple physiological traits. Understanding ecophysiology is therefore dependent on knowledge of leaf habit. A variety of leaf habits exists within forest understory plant communities. Oxalis acetosella is one such understory plant and has long been considered a wintergreen, meaning that it...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.91.9.1371
更新日期：2004-09-01 00:00:00
abstract：:Gas exchange was measured in two subalpine herbs during alternating periods of sun and shade that simulated natural cloud patterns. Stomatal conductance (g) in the subalpine herb Helianthella quinquenervis was reduced by as much as 75% during 5-min shade periods that ranged in photosynthetic photon flux density (PPFD)...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/j.1537-2197.1990.tb13548.x
更新日期：1990-02-01 00:00:00
abstract：:Polyploid speciation is an ongoing, important source of angiosperm diversity. However, the barriers to polyploid speciation and mechanisms of establishment remain poorly understood for all but a few species. Several factors likely to have influenced tetraploid establishment, including barriers to triploid formation, c...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.92.11.1827
更新日期：2005-11-01 00:00:00
abstract：PREMISE:Light is critical in the ability of plants to accumulate chlorophyll. When exposed to far-red (FR) light and then grown in white light in the absence of sucrose, wild-type seedlings fail to green in a response known as the FR block of greening (BOG). This response is controlled by phytochrome A through repressi...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1423
更新日期：2020-02-01 00:00:00
abstract：:The fresh weights of suspension cultures of pear (Pyrus communis) and quince (Cydonia oblonga) increased exponentially for 30 to 40 days after subculturing. Transferring pear cultures to media in which quince cultures had grown for 10 days resulted in a 70% inhibition of callus growth. Transferring quince cultures to ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/j.1537-2197.1986.tb09673.x
更新日期：1986-01-01 00:00:00
abstract：UNLABELLED: PREMISE OF THE STUDY:Allometric relationships among the dimensions of leaf cells, cell walls, and tissues, and whole-leaf thickness and area are likely to have key implications for leaf construction and function, but have remained virtually untested, despite the explosion of interest in allometric analysis...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1200608
更新日期：2013-10-01 00:00:00
abstract：:The timing, geographical locations, causes, and consequences of crop domestication have long been major concerns of archaeologists, and agricultural origins and dispersals are currently more relevant than ever to scientists seeking solutions to elusive problems involving food insecurity and global health disparities. ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1400145
更新日期：2014-10-01 00:00:00
abstract：:Nuclear DNA contents (4C) were estimated by Feulgen microdensitometry in 27 species of slipper orchids. These data and recent information concerning the molecular systematics of Cypripedioideae allow an interesting re-evaluation of karyotype and genome size variation among slipper orchids in a phylogenetic context. DN...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1998-05-01 00:00:00
abstract：:We sequenced the nuclear small subunit ribosomal DNA coding region from 20 members of the Bangiophycidae and from two members of the Florideophycidae to gain insights into red algal evolution. A combined alignment of nuclear and plastid small subunit rDNA and a data set of Rubisco protein sequences were also studied t...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2001-08-01 00:00:00
abstract：PREMISE:Medullary bundles, i.e., vascular units in the pith, have evolved multiple times in vascular plants. However, no study has ever explored their anatomical diversity and evolution within a phylogenetic framework. Here, we investigated the development of the primary vascular system within Nyctaginaceae showing how...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1471
更新日期：2020-05-01 00:00:00
abstract：:Cladistic parsimony analyses of rbcL nucleotide sequence data from 171 taxa representing nearly all tribes and subtribes of Orchidaceae are presented here. These analyses divide the family into five primary monophyletic clades: apostasioid, cypripedioid, vanilloid, orchidoid, and epidendroid orchids, arranged in that ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1999-02-01 00:00:00
abstract：PREMISE OF THE STUDY:General relationships among functional traits have been identified across species, but the forces shaping these relationships remain largely unknown. Adopting an approach from evolutionary biology, we studied similarities and differences in intrapopulation trait correlations among locally co-occurr...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1146
更新日期：2018-09-01 00:00:00
abstract：UNLABELLED:• PREMISE OF THE STUDY:Floral traits play important roles in pollinator attraction and defense against floral herbivory. However, plants may experience trade-offs between conspicuousness to pollinators and herbivore attraction. Comparative studies provide an excellent framework to examine the role of multip...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1400171
更新日期：2014-08-01 00:00:00
abstract：:Traditional farming communities frequently maintain high levels of agrobiodiversity, so understanding their agricultural practices is a priority for biodiversity conservation. The cultural origin of agave spirits (mezcals) from west-central Mexico is in the southern part of the state of Jalisco where traditional farme...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.0800176
更新日期：2009-02-01 00:00:00
abstract：PREMISE OF THE STUDY:High intraspecific cytogenetic variation in the sedge genus Carex (Cyperaceae) is hypothesized to be due to the "diffuse" or non-localized centromeres, which facilitate chromosome fission and fusion. If chromosome number changes are dominated by fission and fusion, then chromosome evolution will re...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1000046
更新日期：2011-01-01 00:00:00
abstract：UNLABELLED:• PREMISE OF THE STUDY:Mountainous regions support high plant productivity, diversity, and endemism, yet are highly vulnerable to climate change. Historical records and model predictions show increasing temperatures across high elevation regions including the Southern Rocky Mountains, which can have a stron...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1500156
更新日期：2015-08-01 00:00:00
abstract：:Bamboo is considered useful for controlling landslides, but we observed numerous shallow-slope failures in forests of big node bamboo (Phyllostachys nidularia) in Sichuan, China. Therefore, we inventoried landslide occurrence and vegetation type along one valley. To quantify bamboo root anchorage, we performed uprooti...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.94.7.1129
更新日期：2007-07-01 00:00:00
abstract：:Microelectrodes were used to study the oxygen concentration within Myrica gale L. nodules. Low oxygen concentrations were found only in the region of the mature, nitrogen-fixing endophyte, and appeared to correspond to clusters of infected host cells. The oxygen concentration in the remainder of the nodule was much hi...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/j.1537-2197.1983.tb12432.x
更新日期：1983-01-01 00:00:00
abstract：:Field surveys of cynipid gall-inducer occurrences on Quercus species were conducted in Florida, North Carolina, and Pennsylvania, USA. All cynipids demonstrated strong host species and organ fidelity. One result of this specialization is effective niche partitioning among cynipids. The host-association patterns of the...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1998-08-01 00:00:00
abstract：:Additional information on the morphology of the vegetative ultimate branches of Archaeopteris roemeriana was obtained by uncovering compression specimens collected in Upper Devonian deposits in Belgium. For the first time, anisophylly, previously inferred from anatomical studies, is demonstrated on one species of the ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2001-04-01 00:00:00
abstract：PREMISE:Within closed-canopy forests, vertical gradients of light and atmospheric CO2 drive variations in leaf carbon isotope ratios, leaf mass per area (LMA), and the micromorphology of leaf epidermal cells. Variations in traits observed in preserved or fossilized leaves could enable inferences of past forest canopy c...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1523
更新日期：2020-08-01 00:00:00
abstract：PREMISE OF THE STUDY:The study of scaling examines the relative dimensions of diverse organismal traits. Understanding whether global scaling patterns are paralleled within species is key to identify causal factors of universal scaling. I examined whether the foliage-stem (Corner's rules), the leaf size-number, and the...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1500439
更新日期：2016-05-01 00:00:00
