Abstract:
:Partial cambial mortality is a growth form that is characteristic of Pinus aristata trees. To better elucidate their cambial death pattern, tree size and aspect of cambial death data were gathered from three Pinus aristata forests in central Colorado, USA. Stripping frequency tended to be higher for larger diameter classes. Partial cambial mortality exhibits significant directionality within each stand. Furthermore, cambial death was measured to be most frequent on the wind-exposed side of stripped trees in two of the three study sites and appeared to be at the third. Data presented here support the hypothesis that wind plays a role in the occurrence of partial cambial mortality in Pinus aristata. The mechanisms by which wind causes cambial mortality remain unclear.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Schauer AJ,Schoettle AW,Boyce RLsubject
Has Abstractpub_date
2001-04-01 00:00:00pages
646-52issue
4eissn
0002-9122issn
1537-2197pii
88/4/646journal_volume
88pub_type
杂志文章abstract::Understanding the role of mother plants as pollen recipients in shaping mating patterns is essential for understanding the evolution of populations and in particular to predict the consequence of habitat fragmentation. Here, we investigated variation in mating patterns due to maternal phenotypic traits, phenological v...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.11.1650
更新日期:2006-11-01 00:00:00
abstract:PREMISE OF THE STUDY:The genus Hoya (Apocynaceae; Asclepiadoideae) is characterized by a set of complex floral characters unique among the asclepiads, but their role in pollination is poorly understood. Here, we report a new mechanism of asclepiad pollination in the wax plant Hoya carnosa: the pollinaria are transferre...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1700078
更新日期:2017-06-01 00:00:00
abstract::Phylogenetic relationships were determined in the Araucariaceae, which are now found mainly in the Southern Hemisphere. This conifer family was well diversified and widely distributed in both hemispheres during the Mesozoic era. The sequence of 1322 bases of the rbcL gene of cpDNA was determined from 29 species of Ara...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-11-01 00:00:00
abstract:PREMISE OF THE STUDY:The presence or absence of a functional copy of a plastid gene may reflect relaxed selection, and may be phylogenetically significant, reflecting shared ancestry. In some liverworts, the plastid gene cysA is a pseudogene (inferred to be nonfunctional). We surveyed 63 liverworts from all major clade...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100010
更新日期:2011-08-01 00:00:00
abstract::Five plant communities in Western Australia, as well as selected desert and Rocky Mountain species of the western USA, were surveyed to evaluate associations among leaf structure, orientational properties, and the sunlight exposure and precipitation characteristic of each community. Selected leaf structural features h...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-01-01 00:00:00
abstract:PREMISE:The cosmopolitan and ecologically important grass subfamily Aristidoideae comprises the widely distributed genus Aristida (250-290 species), Stipagrostis (50 species, with an African-Asian distribution), and Sartidia (five species, Africa and Madagascar). The subfamily includes species with C(3) (Sartidia and a...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100103
更新日期:2011-11-01 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:PREMISE OF THE STUDY:Variation in demographic parameters reflects the life-history strategies of plants in response to specific environments. We aimed to investigate the intraspecific variation in life-history traits of a clonal alpine herb, Gentiana nipponica, in various snowmelt conditions. METHODS:Individual ramets...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1186
更新日期:2018-11-01 00:00:00
abstract::Bennettitales is an extinct group of seed plants with reproductive structures that are similar in some respects to both Gnetales and angiosperms, but systematic relationships among the three clades remain controversial. This study summarizes characters of bennettitalean plants and presents new evidence for the structu...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800209
更新日期:2009-01-01 00:00:00
abstract::To investigate the relationship between the altitudinal distribution of Quercus laceyi and Q. sideroxyla and their physiological responses to drought, we measured relative water content (RWC), water potentials (Ψ(predawn) and Ψ(midday)), photosynthesis (A(max)), stomatal conductance (g), chlorophyll fluorescence (F(v)...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.5.809
更新日期:2007-05-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1987-01-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1356
更新日期:2019-10-01 00:00:00
abstract::Dispersal is an important life history component. Seed settling velocity may be a useful surrogate for the measurement of dispersal ability in wind-dispersed plants, particularly those whose seeds have plumose dispersal structures. I measured settling velocities on seeds of eight species of Asteraceae, including annua...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/j.1537-2197.1992.tb13702.x
更新日期:1992-10-01 00:00:00
abstract::Much of the ultraviolet-B radiation (UV-B) research on plants has concentrated on vegetative plant parts, and only a small fraction has dealt with the reproductive system. The present study analyzed pollen grains of 34 taxa germinated and grown under two levels of UV-B radiation (187 and 460 mW/m2) or no UV-B (control...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-03-01 00:00:00
abstract::The cacti are well-known desert plants, widely recognized by their specialized growth form and essentially leafless condition. Pereskia, a group of 17 species with regular leaf development and function, is generally viewed as representing the "ancestral cactus," although its placement within Cactaceae has remained unc...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.7.1177
更新日期:2005-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100070
更新日期:2011-10-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000118
更新日期:2010-11-01 00:00:00
abstract::Phylogenetic relationships of 38 species of the Alibertia group (Rubiaceae) and two outgroup species were investigated using the nuclear ribosomal 5S nontranscribed spacer (5S-NTS) and the internal transcribed spacers (ITS). Analysis of the data sets separately and in combination resulted in several well-supported and...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-07-01 00:00:00
abstract::Serpentine soils are a model system for the study of plant adaptation, speciation, and species interactions. Serpentine soil is an edaphically stressful, low productivity soil type that hosts stunted vegetation and a spectacular level of plant endemism. One of the first papers on serpentine plant endemism was by Arthu...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1300349
更新日期:2014-02-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章,评审
doi:10.3732/ajb.1400197
更新日期:2014-09-01 00:00:00
abstract::We investigated the hypothesis that dandelion clones (Taraxacum officinale Weber, sensu lato; Asteraceae) differ in their floral stage timing characteristics under a constant set of environmental conditions. To test this hypothesis, plants representing nine different dandelion clones (identified by DNA fingerprinting)...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.11.1828
更新日期:2004-11-01 00:00:00
abstract::Paniculate agaves from tropical deserts depend on nectar-feeding bats for their reproduction, while species from extratropical areas near the northern limit of Leptonycteris curasoae are pollinated by diurnal and nocturnal insects and birds. Agave angustifolia is a paniculate agave with a broad distribution in Mexico ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.7.1016
更新日期:2003-07-01 00:00:00
abstract::Axillary meristems play a fundamental role in inflorescence architecture. Maize (Zea mays) inflorescences are highly branched panicles because of the production of multiple types of axillary meristems. We used auxin transport inhibitors to show that auxin transport is required for axillary meristem initiation in the m...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.11.1745
更新日期:2007-11-01 00:00:00
abstract:PREMISE OF THE STUDY:Hybridization and polyploidization (allopolyploidy) are ubiquitous in the evolution of plants, but tracing the origins and subsequent evolution of the constituent genomes of allopolyploids has been challenging. Genome doubling greatly complicates genetic analyses, and this has long hindered investi...
journal_title:American journal of botany
pub_type: 杂志文章,评审
doi:10.3732/ajb.1100395
更新日期:2012-02-01 00:00:00
abstract:PREMISE OF THE STUDY:The stability of the bimodal karyotype found in Agave and closely related species has long interested botanists. The origin of the bimodal karyotype has been attributed to allopolyploidy, but this hypothesis has not been tested. Next-generation transcriptome sequence data were used to test whether ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100537
更新日期:2012-02-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900063
更新日期:2009-08-01 00:00:00
abstract:PREMISE OF THE STUDY:Koelreuteria (Sapindaceae) has four extant deciduous tree species, disjunctly distributed in eastern Asia and the Fiji Islands. While K. paniculata is widely cultivated, the biogeographic origin and evolutionary history of Koelreuteria remain unclear. METHODS:Fruits, pollen, wood, and leaves of cl...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200415
更新日期:2013-02-01 00:00:00
abstract::Ontogenetic trends in the wood structure of Nepalese Rhododendron were studied in 15 specimens of two tree and four subtree species. Average growth ring width was constant from pith to bark in spite of occurrences of extremely narrow, false, or discontinuous rings. Vessel density, vessel area, vessel element length, a...
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 OF THE STUDY:Factors shaping spatiotemporal patterns of associations in mutualistic systems are poorly understood. We used the lichen-forming fungi Peltigera and their cyanobacterial partners Nostoc to investigate the spatial structure of this symbiosis at an intrabiome scale and to identify potential factors s...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1119
更新日期:2018-07-01 00:00:00
abstract::Phylogenetic analyses of Meliaceae, including representatives of all four currently recognized subfamilies and all but two tribes (32 genera and 35 species, respectively), were carried out using DNA sequence data from three regions: plastid genes rbcL, matK (partial), and nuclear 26S rDNA (partial). Individual and com...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.3.471
更新日期:2003-03-01 00:00:00