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. Consistent with histological studies, derivatives of the lateral root initial as well as the cells of the adjacent inner cortex and pericycle of the parent root also continued to synthesize DNA. RNA and protein synthetic activities were found to be higher in the lateral root initials than in the endodermal initials of the same longitudinal layer. The data suggest a role for nucleic acid and protein synthesis during cytodifferentiation of a potential endodermal cell into a lateral root initial.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Lin BL,Raghavan Vsubject
Has Abstractpub_date
1991-01-01 00:00:00pages
740-6issue
6eissn
0002-9122issn
1537-2197journal_volume
78pub_type
杂志文章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::Individual plants of Asclepias exaltata (Asclepiadaceae) typically express an unusual self-incompatibility system under single-gene control. Hand-pollinations performed in six natural populations detected occasional self-fertile plants. The frequency of self-fertile individuals ranged from 0 to 34.0% and differed sign...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract::Light propagation and distribution inside leaves have been recognized as important processes influencing photosynthesis. Monochromatic light absorption across the mesophyll was measured using chlorophyll fluorescence generated from illumination of the cut edge (epi-illumination), as well as the adaxial or abaxial surf...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.9.1425
更新日期:2005-09-01 00:00:00
abstract::Scaling relationships among photosynthetic rate, foliar nutrient concentration, and leaf mass per unit area (LMA) have been observed for a broad range of plants. Leaf traits of the carnivorous pitcher plant Darlingtonia californica, endemic to southern Oregon and northern California, USA, differ substantially from the...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.7.1085
更新日期:2005-07-01 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:Microsatellite loci were developed for the endangered species Pityopsis ruthii and will permit genetic and conservation studies of the species. METHODS AND RESULTS:A microsatellite-enriched library was used to develop 12 polymorphic microsatellite loci for P. ruthii. The loci amplified perfect and...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100100
更新日期:2011-12-01 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: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::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::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::Atriplex prostrata Boucher, a facultative halophyte, exhibits significant reduction in height and biomass and in the width of the cortex and vascular tissue under saline conditions. Therefore, the goal of this investigation was to determine the effect of salinity on plant growth as well as on the patterns of lignifica...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-09-01 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::Breadfruit (Artocarpus altilis, Moraceae), a traditional starch crop in Oceania, has enjoyed legendary status ever since its role in the infamous mutiny aboard the H.M.S. Bounty in 1789, yet its origins remain unclear. Breadfruit's closest relatives are A. camansi and A. mariannensis. DNA fingerprinting data (AFLP, am...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.5.760
更新日期:2004-05-01 00:00:00
abstract:PREMISE OF THE STUDY:Climate cycles of the Quaternary have impacted plants at a global scale, leaving behind a complex genetic legacy. Species of the northern Rocky Mountains of North America were exposed to more uniform glacial patterns than the central and southern ranges, where synergistic relationships between temp...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1259
更新日期:2019-03-01 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::We demonstrated that "orchid mycorrhiza," a specialized mycorrhizal type, appeared in the common ancestor of the largest plant family Orchidaceae and that the fungal partner shifted from Glomeromycota to a particular clade of Basidiomycota in association with this character evolution. Several unique mycorrhizal charac...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900101
更新日期:2009-11-01 00:00:00
abstract:PREMISE OF THE STUDY:Collinsia was the subject of classic biosystematic studies by Garber and colleagues and is increasingly investigated to address major evolutionary questions. Lack of phylogenetic data from more than one gene region and one taxonomic exemplar has left relationships, diversity, and phytogeography of ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000346
更新日期:2011-04-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Sphagnum dominates vast expanses of wetland habitats throughout the northern hemisphere and species delimitation within the genus is important because floristic changes associated with a warming global climate may have measureable impacts on large-scale ecological processes. Most north...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200630
更新日期:2013-06-01 00:00:00
abstract::We developed an improved cytological protocol for producing high quality, light microscope images of plant meiotic chromosomes. Because the technique works on species with small genomes and thick microsporocyte cell walls, it should be useful for studying the wild relatives of Arabidopsis and other eudicots with small...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.12.2063
更新日期:2007-12-01 00:00:00
abstract::In a 3-yr study, we examined the pollinator guild and intersexual floral characteristics of the dioecious, perennial cloudberry (Rubus chamaemorus), which flowers in early spring. The findings contribute to our general understanding of pollination ecology at high latitudes and provide important information for the com...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800102
更新日期:2009-06-01 00:00:00
abstract:PREMISE OF THE STUDY:Geographic patterns of biodiversity have long inspired interest in processes that shape the assembly, diversity, and dynamics of communities at different spatial scales. To study mechanisms of community assembly, ecologists often compare spatial variation in community composition (beta-diversity) a...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500079
更新日期:2016-01-01 00:00:00
abstract::Although theory has demonstrated rather low levels of gene flow are sufficient to counteract opposing mutation, drift, and selection, widespread recognition of the evolutionary importance of gene flow has come slowly. The perceived role of gene flow as an evolutionary force has vacillated over the last century. In the...
journal_title:American journal of botany
pub_type: 杂志文章,评审
doi:10.3732/ajb.1400024
更新日期:2014-05-01 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:UNLABELLED:• PREMISE OF THE STUDY:Flower color is one of the best-studied floral traits in terms of its genetic basis and ecological significance, yet few studies have examined the processes that shape its evolution across deep timescales. Advances in comparative methods along with larger phylogenies for floral radiat...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500163
更新日期:2015-07-01 00:00:00
abstract::Plant tropisms play a fundamental role in shaping the growth form of plants, and these fascinating movements are the focus of this thematic issue of the American Journal of Botany. The issue includes 16 reviews of the current literature and eight original manuscripts written by a diverse group of international experts...
journal_title:American journal of botany
pub_type:
doi:10.3732/ajb.1200591
更新日期:2013-01-01 00:00:00
abstract:PREMISE OF THE STUDY:Several members of Selaginella are renowned for their ability to survive extreme drought and "resurrect" when conditions improve. Many of these belong to subgenus Tetragonostachys, a group of ∼45 species primarily found in North and Central America, with substantial diversity in the Sonoran and Chi...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200426
更新日期:2013-08-01 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::Six of 14 species of Triteleia were studied. All possess septal nectaries, raphides in the ovary wall, an anatropous and crassinucellate ovule with a micropyle formed by the inner integument only, and parietal cells. A short and thick nucellus, which is not penetrated by the embryo sac, has a one-layered apical epider...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.6.937
更新日期:2003-06-01 00:00:00
abstract::In turnip mitochondria the cox2 gene is partially contained within a 2-kb (kilobase) direct repeat that is the site of homologous recombination events that generate subgenomic molecules. Because of its partial presence within the direct repeat, the turnip cox2 gene exists in four genomic contexts, two on the master ch...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract:PREMISE OF THE STUDY:Areas lacking dominant plants, or gaps, can support high diversity and specialist species. Previous chronosequence research in Florida rosemary scrub showed indistinct gap area patterns with fire and the dependence of certain species on gaps. We hypothesized that fire and gap size would affect exti...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1700175
更新日期:2017-12-01 00:00:00