Abstract:
:Intensified ultraviolet-B radiation or UV-B (wavelengths between 280 and 320 nm) can delay flowering and diminish lifetime flower production in a few plants. Here we studied the effects of enhanced UV-B on floral traits crucial to pollination and pollinator reproduction. We observed simultaneous flowering responses of a new crop plant, Limnanthes alba (Limnathaceae), and a wildflower, Phacelia campanularia (Hydrophyllaceae), to five lifetime UV-B dosages ranging between 2.74 and 15.93 kJ·m·d. Floral traits known to link plant pollination with bee host preference, host fidelity and larval development were measured. Intensified UV-B had no overall effect on nectar and pollen production of L. alba and P. campanularia flowers. A quadratic relationship between UV-B and nectar sugar production occurred in P. campanularia and showed that even subambient UV-B dosages can be deleterious for a floral trait. Other floral responses to UV-B were more dramatic and idiosyncratic. As UV-B dosage increased, L. alba plants were less likely to flower, but suffered no delays in flowering or reductions to lifetime flower production for those that did flower. Conversely, an equal proportion of P. campanularia plants flowered under all UV-B treatments, but these same plants experienced delayed onset to bloom and produced fewer flowers at greater UV-B intensities. Therefore, intensified UV-B elicits idiosyncratic responses in flowering phenology and flower production from these two annual plants. Diurnal patterns in nectar and pollen production strongly coincided with fluctuating humidity and only weakly with UV-B dosage. Overall, our results indicated that intensified UV-B can alter some flowering traits that impinge upon plant competition for pollinator services, as well as plant and pollinator reproductive success.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Sampson BJ,Cane JHsubject
Has Abstractpub_date
1999-01-01 00:00:00pages
108-14issue
1eissn
0002-9122issn
1537-2197pii
86/1/108journal_volume
86pub_type
杂志文章abstract:PREMISE OF THE STUDY:Drosera peltata var. nipponica, an element of the East Asia warm-temperate vegetation, and D. rotundifolia, a widely distributed boreal species, reach one of their northernmost and southernmost limits, respectively, on the Korean Peninsula. Because the Last Glacial Maximum (LGM)-Holocene dynamics o...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200486
更新日期:2013-11-01 00:00:00
abstract:PREMISE OF THE STUDY:Little is known about the effect of environmental conditions on seed dormancy break at the community level or how it could be affected by climate change. This study tested the effects of storage conditions on germination of 489 species from high-elevation natural grasslands on the Tibet Plateau. M...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000043
更新日期:2011-01-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-02-01 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:New microsatellite primers were developed for testing genetic differentiation within Nothoceros aenigmaticus and their potential use in other Nothoceros species. The microsatellites are designed to investigate partitioning of genetic variation in a taxon with a peculiar sex allopatry in the souther...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100392
更新日期:2012-03-01 00:00:00
abstract::Self-incompatibility (SI) is an effective method for limiting self-fertilization in flowering plant species, but there are circumstances in which an otherwise functional SI system may fail. One of the most intriguing of these is the induction of selfing by mixed loads of self and heterospecific pollen (the mentor effe...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-06-01 00:00:00
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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
abstract::The shoot apical meristem (SAM) produces stem and initiates leaves. Its structure is maintained despite a continuous flow of cells basipetally from the distal portion of the meristem. The apoplasm and symplasm are the obvious means of cell integration, and their role in chemical cell-to-cell signaling is known. Howeve...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.9.1277
更新日期:2004-09-01 00:00:00
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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
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-04-01 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::Chromosome numbers and karyotypes of species of Orobanche, Cistanche, and Diphelypaea (Orobanchaceae) were investigated, and 108 chromosome counts of 53 taxa, 19 counted for the first time, are presented with a thorough compilation of previously published data. Additionally, karyotypes of representatives of these gene...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.3.439
更新日期:2004-03-01 00:00:00
abstract::Morphology and development of the female flowers in Geonoma interrupta are described and compared with other taxa within Arecaceae. Inflorescences are pleiothyrses. Cincinni are immersed in pits and arranged according to the Fibonacci pattern along the rachillae. The gynoecium is composed of three free carpels in earl...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.2.220
更新日期:2002-02-01 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.1000289
更新日期:2011-03-01 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
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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
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1428
更新日期:2020-02-01 00:00:00
abstract:PREMISE OF THE STUDY:Large genera provide remarkable opportunities to investigate patterns of morphological evolution and historical biogeography in plants. A molecular phylogeny of the species-rich and morphologically and ecologically diverse genus Mimosa was generated to evaluate its infrageneric classification, reco...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000520
更新日期:2011-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000172
更新日期:2010-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.7.1085
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.1100154
更新日期:2011-11-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-05-01 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:PREMISE:Declines in reproductive capabilities with increasing age are common across the tree of life. However, in plants, mating system traits have rarely been tested for signs of senescence. Since reproduction is often resource limited, we might expect outcrossing and selfing taxa to allocate these resources different...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1346
更新日期:2019-09-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Invasive plant species threaten native plants in multiple ways, one of which is genetic assimilation through hybridization. However, information regarding hybridization between related alien and native plant species is generally lacking. In Hawaii, the invasive Central American species...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1300018
更新日期:2013-06-01 00:00:00
abstract:PREMISE OF THE STUDY:Recurrent formation of polyploid taxa is a common observation in many plant groups. Haploid, cytoplasmic genomes like the plastid genome can be used to overcome the problem of homeologous genes and recombination in polyploid taxa. Fragaria (Rosaceae) contains several octo- and decaploid species. We...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1085
更新日期:2018-05-01 00:00:00
abstract::The relationship between near-infrared reflectance at 800 nm (NIRR) from leaves and characteristics of leaf structure known to affect photosynthesis was investigated in 48 species of alpine angiosperms. This wavelength was selected to discriminate the effects of leaf structure vs. chemical or water content on leaf ref...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-02-01 00:00:00
abstract:UNLABELLED:• PREMISE OF THE STUDY:Accurate assessments of biodiversity are paramount for understanding ecosystem processes and adaptation to change. Invasive species often contribute substantially to local biodiversity; correctly identifying and distinguishing invaders is thus necessary to assess their potential impac...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400466
更新日期:2015-07-01 00:00:00
abstract:PREMISE OF THE STUDY:Microsatellite markers were developed for the dove tree, Davidia involucrata (Cornaceae), a Tertiary relict currently endemic to China, to investigate its population genetics and phylogeography. METHODS AND RESULTS:Using the Fast Isolation by AFLP of Sequences Containing repeats (FIASCO) protocol,...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100414
更新日期:2012-03-01 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