Abstract:
:The hollow stem of Equisetum giganteum owes its mechanical stability to an outer ring of strengthening tissue, which provides stiffness and strength in the longitudinal direction, but also to an inner lining of turgid parenchyma, which lends resistance to local buckling. With a height >2.5 m isolated stems are mechanically unstable. However, in dense stands individual stems support each other by interlacing with their side branches, the typical growth habit of semi-self-supporters.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Spatz H,Köhler L,Speck Tsubject
Has Abstractpub_date
1998-03-01 00:00:00pages
305issue
3eissn
0002-9122issn
1537-2197pii
85/3/305journal_volume
85pub_type
杂志文章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::We provide an overview of research on climbing plants from Charles Darwin to the present day. Following Darwin's interests, this review will focus on functional perspectives including attachment mechanisms and stem structure and function. We draw attention to a number of unsolved problems inviting future research. The...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900045
更新日期:2009-07-01 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:PREMISE OF THE STUDY:Microsatellite primers were developed in the traditional Tibetan medicinal plant Halenia elliptica D. Don to investigate its genetic diversity and population genetic structure. METHODS AND RESULTS:Using the Fast Isolation by AFLP of Sequences Containing (FIASCO) repeats protocol, 24 primer sets we...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000534
更新日期:2011-07-01 00:00:00
abstract::The evolutionary history of maize (Zea mays subsp. mays) is of general interest because of its economic and scientific importance. Here we show that many cellular traits described previously in developing caryopses of maize are also seen in its wild progenitor teosinte (Zea mays subsp. parviglumis). These features, ea...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900059
更新日期:2009-10-01 00:00:00
abstract::Maximum parsimony analysis of DNA sequence data from the internal and external transcribed spacer (ITS and ETS) regions of 18S-26S nuclear ribosomal DNA and the 3' trnK intron of chloroplast DNA from over 60 populations of Lasthenia sect. Amphiachaenia yielded a well-supported tree showing that the most common species...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.7.1103
更新日期:2002-07-01 00:00:00
abstract::Seventy-four nucleotide sequences from the ITS regions of nuclear ribosomal DNA and 76 from the trnL-trnF spacer of chloroplast DNA were used to address the origin of tetraploid Cardamine amporitana, the conspecifity of central Italian and northeastern Spanish populations, and the possible cause for such geographic di...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.8.1231
更新日期:2004-08-01 00:00:00
abstract:PREMISE OF THE STUDY:Conifers are an important living seed plant lineage with an extensive fossil record spanning more than 300 million years. The group therefore provides an excellent opportunity to explore congruence and conflict between dated molecular phylogenies and the fossil record. METHODS:We surveyed the curr...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1143
更新日期:2018-09-01 00:00:00
abstract::Competition and herbivory are ubiquitous environmental challenges that affect most plants. We examined the influence of phenotypic responses to either competition or herbivory on the subsequent response of the plants to the other factor. The stem-elongation response of Chenopodium album to light competition attenuated...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.1.21
更新日期:2005-01-01 00:00:00
abstract::A long-term survey (1990-2000) of pollination modes of 86 tree species was carried out at Kakachi, a mid-elevation wet forest site in southern Western Ghats, India. Observations were made on 86 tree species. This comprises 80% of the total arborescent species present in the site. Approximately 75% of these species wer...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.4.650
更新日期:2003-04-01 00:00:00
abstract::The plastid trnL-F region has proved useful in molecular phylogenetic studies addressing diverse evolutionary questions from biogeographic history to character evolution in a broad range of plant groups. An important assumption for phylogenetic reconstruction is that data used in combined analyses contain the same phy...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.6.1003
更新日期:2007-06-01 00:00:00
abstract:PREMISE OF THE STUDY:Gravity has been a major force throughout the evolution of terrestrial organisms, and plants have developed exquisitely sensitive, regulated tropisms and growth patterns that are based on the gravity vector. The nullified gravity during spaceflight allows direct assessment of gravity roles. The mic...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200343
更新日期:2013-01-01 00:00:00
abstract::In spite of the ecological and economic importance of temperate bamboos, relatively little is known about their population biology or evolutionary history. Recently, hybridization has emerged as a potential source of diversity in this group, as well as an underlying cause of taxonomic problems. As part of a broader ph...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900244
更新日期:2010-03-01 00:00:00
abstract:PREMISE:Hyperaccumulation of heavy metals in plants has never been documented from Central America or Mexico. Psychotria grandis, P. costivenia, and P. glomerata (Rubiaceae) have been reported to hyperaccumulate nickel in the Greater Antilles, but they also occur widely across the neotropics. The goals of this research...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1362
更新日期:2019-10-01 00:00:00
abstract::Phylogenetic analysis of DNA sequences of the chloroplast genes rcbL and ndhf revealed a highly supported clade composed of the families Plantaginaceae, Callitrichaceae, and Hippuridaceae in close association with the model organism Antirrhinum majus and other members of family Scrophulariaceae. Plantago has miniature...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-08-01 00:00:00
abstract::Natural recruitment of oaks appears to be declining throughout the northern hemisphere. Summer drought poses a potentially important barrier to oak recruitment in southern California. To evaluate this barrier, we grew evergreen Quercus agrifolia and deciduous Q. lobata from seeds near parental trees. We measured water...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800247
更新日期:2009-04-01 00:00:00
abstract:PREMISE OF THE STUDY:Giant cacti species possess long cylindrical stems that store massive amounts of water and other resources to draw on for photosynthesis, growth, and reproduction during hot and dry conditions. Across all giant cacti taxa, stem photosynthetic surface area to volume ratio (S:V) varies by several fol...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1166
更新日期:2018-10-01 00:00:00
abstract::Members of tribe Vandeae (Orchidaceae) form a large, pantropical clade of horticulturally important epiphytes. Monopodial leafless members of Vandeae have undergone extreme reduction in habit and represent a novel adaptation to the canopy environment in tropical Africa, Asia, and America. To study the evolution of mon...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.5.770
更新日期:2006-05-01 00:00:00
abstract::Lxm1-O, a dominant EMS (ethyl methanesulfonate) induced mutation in maize (Zea mays, Poaceae), was originally reported to affect the blade/sheath boundary over the midrib region of the leaf. Here we present a more extensive analysis of the Lxm phenotype in nine different inbred lines. Lxm leaves are longer and narrowe...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-04-01 00:00:00
abstract::Gregor Mendel was a 19(th) century priest and botanist who developed the fundamental laws of inheritance. The year 2000 marked a century since the rediscovery of those laws and the beginning of genetics. Although Mendel is now recognized as the founder of genetics, significant controversy ensued about his work through...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-05-01 00:00:00
abstract::The balance between clonal and sexual reproduction can vary widely among plant populations, and the extent of clonality may be influenced by the combined effects of historical land use and variation in environmental conditions. We investigated patterns of clonal spread in five Trillium cuneatum populations, two in the...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.2007159
更新日期:2008-10-01 00:00:00
abstract::The pattern of DNA, RNA, and protein synthesis during lateral root initiation in Marsilea quadrifolia L. was monitored by autoradiography of incorporated of 3H-thymidine, 3H-uridine, and 3H-leucine, respectively. DNA synthesis was associated with the enlargement of the lateral root initial prior to its division. Con...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1991-01-01 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:PREMISE OF THE STUDY:The life histories of lichen fungi are not well known and cannot be readily studied in laboratory culture. This work documents in situ the complete life cycle of the widespread crustose lichen Calopadia puiggarii, which reproduces sexually and asexually on the surfaces of leaves. METHODS:Plastic c...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400272
更新日期:2014-11-01 00:00:00
abstract:PREMISE OF THE STUDY:Astragalus sect. Humillimi is distributed across the southwestern United States and contains two endangered taxa, A. cremnophylax var. cremnophylax and A. humillimus. The former was originally described from the South Rim of the Grand Canyon. Analysis of individuals discovered on the North Rim of t...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1157
更新日期:2018-10-01 00:00:00
abstract::We examined the function of floral traits associated with buzz pollination through studies of Rhexia virginica (Melastomataceae) in the Muskoka region of Ontario, Canada. Controlled pollinations demonstrated that the species is self-compatible, but dependent on insects for pollen transfer. Bumble bees made 82 and 90% ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-04-01 00:00:00
abstract::Because leaf pubescence of the desert shrub Encelia farinosa increases in response to drought and influences photosynthesis and transpiration, we hypothesized that differences in water availability across the range of this species may result in genetic differentiation for pubescence and associated productivity traits....
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.10.1481
更新日期:2003-10-01 00:00:00
abstract:PREMISE OF THE STUDY:Robust markers are required (inter alia) for assessing origins of Calophyllum inophyllum populations on the Bonin Islands, Japan. Therefore, informative expressed sequence tag (EST)-based microsatellite or simple sequence repeat (SSRs) markers in the species were sought. METHODS AND RESULTS:Using ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100299
更新日期:2012-01-01 00:00:00
abstract::Marchantia inflexa, a dioecious thallose liverwort, is sexually dimorphic in clonal expansion traits. We used selection analyses to measure the magnitude and direction of selection on clonal fitness to uncover possible mechanisms for the maintenance of preadult sexually dimorphic characters. We planted replicates of g...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.4.592
更新日期:2002-04-01 00:00:00
abstract::The genus Rosa has a complex evolutionary history caused by several factors, often in conjunction: extensive hybridization, recent radiation, incomplete lineage sorting, and multiple events of polyploidy. We examined the applicability of AFLP markers for reconstructing (species) relationships in Rosa, using UPGMA clus...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.95.3.353
更新日期:2008-03-01 00:00:00