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 surfaces of the leaf. Species were selected that had basic leaf types: laminar leaf with adaxial palisade layer (Rhododendron catawbiense), needle with palisade (Abies fraseri), and needle without palisade (Picea rubens). Fluorescence was more evenly distributed across the mesophyll for adaxially illuminated leaves with a palisade cell layer, as well as for the needles (cylindrical) without palisade, when compared to fluorescence generated by abaxial illumination. Moreover, fluorescence from green light illumination remained high across the mesophyll of adaxially illuminated R. catawbiense, indicating a possible influence of mesophyll structure on internal light distribution beyond that of chlorophyll levels. These data support the idea that light propagation within the mesophyll is associated with asymmetric mesophyll structure, in particular the presence of palisade cell layers. In addition, we propose that the evolution of a more cylindrical leaf form, such as found in conifer species, may be a structural solution to excessive sunlight that replaces the highly differentiated mesophyll found in most laminar-leaved species.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Johnson DM,Smith WK,Vogelmann TC,Brodersen CRdoi
10.3732/ajb.92.9.1425subject
Has Abstractpub_date
2005-09-01 00:00:00pages
1425-31issue
9eissn
0002-9122issn
1537-2197pii
92/9/1425journal_volume
92pub_type
杂志文章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: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::The circumscription and relationships of genera within the tribe Melanthieae (29 representative taxa) were evaluated using parsimony analyses of ITS (nuclear ribosomal) and trnL-F (plastid) DNA sequence data, alone and in combination. Proposed new generic circumscriptions, strongly supported by the tree statistics and...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-09-01 00:00:00
abstract:PREMISE OF THE STUDY:We isolated and characterized microsatellite markers for the California poppy, Eschscholzia californica, which is an invasive species in central Chile. METHODS AND RESULTS:A total of eight polymorphic and six monomorphic loci were developed for the species. Between one and 12 alleles were observed...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200076
更新日期:2012-09-01 00:00:00
abstract:PREMISE OF THE STUDY:The species boundaries of wild and cultivated potatoes are controversial, with most of the taxonomic problems in the cultivated potato clade. We here provide the first in-depth phylogenetic study of the cultivated potato clade to explore possible causes of these problems. METHODS:We examined 131 d...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1008
更新日期:2018-01-01 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::Parsimony, likelihood, and Bayesian analyses of nuclear ITS and plastid trnL-F DNA sequence data are presented for the giant genus Croton (Euphorbiaceae s.s.) and related taxa. Sampling comprises 88 taxa, including 78 of the estimated 1223 species and 29 of the 40 sections previously recognized of Croton. It also incl...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.9.1520
更新日期:2005-09-01 00:00:00
abstract::The response of axillary buds to floral stimulus activity in stem pieces was examined in two near-isogenic cultivars of tobacco that differ in the recessive maryland mammoth (mm) allele, which confers short-day behavior. All axillary buds from day-neutral plants assayed on six-internode stem pieces made few nodes (les...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-07-01 00:00:00
abstract:PREMISE OF STUDY:Although there is increasing recognition of the effects of plant intraspecific diversity on consumers, the mechanisms by which such effects cascade-up to higher trophic levels remain elusive. METHODS:We evaluated the effects of plant (lima bean, Phaseolus lunatus) intraspecific diversity on a suite of...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600234
更新日期:2016-10-01 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::• Premise of the study: Tropical forests are the most species-rich terrestrial communities on Earth, and understory trees and shrubs comprise a large fraction of their plant species diversity, especially at high rainfalls. The mechanisms responsible for generating such high levels of diversity remain unknown. One hypo...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1300460
更新日期:2014-07-01 00:00:00
abstract:PREMISE OF THE STUDY:We developed the first set of microsatellite markers for the passion fruit, Passiflora cincinnata, to provide tools for further study of its genetic diversity and to support current conservation and genetic studies. METHODS AND RESULTS:We used a microsatellite-enriched library approach to isolate ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100477
更新日期:2012-04-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:An anatomical examination of dry and fleshy fruits within the Solanaceae was carried out to identify comparable stages throughout development as well as features exclusive to each type of fruit. We studied fruit development of Nicotiana and Petunia, which have the plesiomorphic capsula...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100097
更新日期:2011-09-01 00:00:00
abstract::Terrestrial plant leaves are complex structures of composite materials. Resistance to fracture is achieved by a number of mechanisms, which operate at the molecular, cell, tissue, and structural levels. Leaves of dicots have different venation patterns and cell wall volume fractions from those of grasses, and conseque...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.10.1531
更新日期:2006-10-01 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::This paper reports the frequency of spontaneous amphiploids or neopolyploids in experimental interspecific hybrids in two annual sections of Gilia (Polemoniaceae, sects. Arachnion and Gilia, x = 9). In each section the species were intercrossed in numerous hybrid combinations to obtain an array of F1 hybrid types; sev...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.8.1197
更新日期:2002-08-01 00:00:00
abstract::Caryophyllaceae is a principally holarctic family including around 2200 species often classified into the three subfamilies Alsinoideae, Caryophylloideae, and Paronychioideae. Complex and possibly homoplasious morphological characters within the family make taxa difficult to delimit and diagnose. To explore part of th...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.3.399
更新日期:2006-03-01 00:00:00
abstract::To our knowledge, xylary reaction tissue has never been reported in a forage crop species. Here we report the discovery of reaction tissue in a transgenic line of Medicago sativa (pC3H, for the gene for p-coumarate-3-hydroxylase) with reduced lignin content and in the wild-type (WT) line. Based on microscopy and biome...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.6.912
更新日期:2007-06-01 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::Chloroplast DNA (cpDNA) is maternally inherited in the majority, but not all, of angiosperm species. The mode of inheritance of cpDNA is a critical determinant of its molecular evolution and of its population genetic structure. Here, we present the results of investigations of the inheritance of cpDNA in Silene vulgar...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.8.1333
更新日期:2007-08-01 00:00:00
abstract:PREMISE OF THE STUDY:Microsatellites were developed for the native, perennial herbs Houstonia longifolia and H. purpurea to establish rates and patterns of hybridization among these and other closely related lineages within the genus. METHODS AND RESULTS:Seven primer sets were developed and tested using populations ac...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000294
更新日期:2011-02-01 00:00:00
abstract::The genus Caltha (Ranunculaceae) consists of 10 species of low-growing, perennial herbs distributed throughout the moist temperate and cold regions of both the Northern and Southern Hemispheres. Traditionally, the species have been divided into two sections: section Psychrophila in the Southern Hemisphere with diploph...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.2.247
更新日期:2004-02-01 00:00:00
abstract::Senna (Leguminosae) is a large, widespread genus that includes species with enantiostylous, asymmetric flowers and species with extrafloral nectaries. Clarification of phylogenetic relationships within Senna based on parsimony analyses of three chloroplast regions (rpS16, rpL16, and matK) provides new insights on the ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.2.288
更新日期:2006-02-01 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::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::We assessed the effects of local environment on survival, growth, and development in six clones (genotypes) of Vallisneria americana grown at five sites in the Huron-Erie Corridor. Detrimental effects of local environment on plant performance (rate of clonal growth, leaf and root production, surface area of leaves and...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-12-01 00:00:00
abstract::New individuals in clonal populations arise through the recruitment of sexual or clonal offspring. The predominance of one type of regeneration over the other has been correlated with different selective environmental pressures. We compared the reproductive mode (sexual through seeds and vegetative through plantlets o...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.4.505
更新日期:2006-04-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Vessels are the chief conduit for long-distance water transport in the majority of flowering plants. Vessel length is a key trait that determines plant hydraulic efficiency and safety, yet relatively little is known about this xylem feature. • METHODS:We used previously published stud...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200140
更新日期:2012-10-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:The Malpighiaceae include ∼1300 tropical flowering plant species in which generic definitions and intergeneric relationships have long been problematic. The goals of our study were to resolve relationships among the 11 generic segregates from the New World genus Mascagnia, test the mon...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000146
更新日期:2010-12-01 00:00:00
abstract:PREMISE OF THE STUDY:A key question in evolutionary biology is why some clades are more successful by being widespread geographically, biome diverse, or species-rich. To extend understanding of how shifts in area, biomes, and pollinators impact diversification in plants, we examined the relationships of these shifts to...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1268
更新日期:2019-04-01 00:00:00