Abstract:
:Interspecific hybridization is considered a possible mechanism of plant diversification. The Andes are a hotspot of biodiversity, but hybridization in Andean taxa has so far not been investigated intensively. The current study investigates crossability in Caiophora (Loasaceae subfam. Loasoideae) by experimental interspecific hybridization of seven different species. Hand pollination was undertaken, developing fruits counted, thousand (seed) grain weights, and seed viability were examined. Cross pollination led to some fruit set in 36 of the 37 different combinations. Overall fruit set was virtually identical irrespective of the combination of parental plants. Mean germination rates were much higher in hybrid seeds, indicating a marked heterosis effect and the possible presence of an inbreeding depression in the source populations: In experimental hybridization the divergent taxa of Caiophora behave like isolated, inbred populations of a single species. Allopatry and different habitat preferences seem to be the key factors keeping the (interfertile) taxa of Caiophora apart in the apparent absence of both postmating isolating mechanisms and obvious isolating mechanisms in phenology and floral biology. Interspecific hybrids reported from the wild appear to be the result of secondary contact due to human impact.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Ackermann M,Achatz M,Weigend Mdoi
10.3732/ajb.2007403subject
Has Abstractpub_date
2008-09-01 00:00:00pages
1109-21issue
9eissn
0002-9122issn
1537-2197pii
95/9/1109journal_volume
95pub_type
杂志文章abstract:PREMISE OF THE STUDY:Phenological mismatch has received attention in plant-pollinator interactions, but less so in seed dispersal mutualisms. We investigated whether the seasonal availability of myrmecochorous seeds is well matched to the seasonal activity patterns of seed-dispersing ants. METHODS:We compared seasonal...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1214
更新日期:2019-01-01 00:00:00
abstract::In contrast to most angiosperms, in which fertilization occurs 1 or 2 days after pollination, in some plant orders, including the Fagales, fertilization is delayed from 4 days to more than 1 year, raising questions regarding why fertilization is delayed and where and how pollen tubes remain in the pistil during the de...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.12.1748
更新日期:2006-12-01 00:00:00
abstract::Sex ratio and sexual dimorphism in physiology and growth were studied in the dioecious tree Ilex aquifolium at two localities in northern Spain. Genet sex ratio was significantly male biased in one locality but not in the other. However, ramet and flowering ramet sex ratios were male biased at both study sites. Males ...
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:Gynomonoecy is an infrequent sexual system in angiosperms, although widely represented within the Asteraceae family. Currently, the hypothesis of two nuclear loci controling gynomonoecy is the most accepted. However, the genic interactions are still uncertain. Anacyclus clavatus, A. homogamos, and A. valentinus...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1414
更新日期:2020-01-01 00:00:00
abstract:PREMISE OF THE STUDY:This paper investigates the occurrence and evolution of aluminum (Al) accumulation within ferns and lycophytes, which is characterized by Al concentrations above 1000 mg·kg-1 in aboveground plant tissues. We hypothesize that this feature is more common in ferns than in angiosperms, and potentially ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600381
更新日期:2017-04-01 00:00:00
abstract:PREMISE OF THE STUDY:The fossil record of Agathis historically has been restricted to Australasia. Recently described fossils from the Eocene of Patagonian Argentina showed a broader distribution than found previously, which is reinforced here with a new early Paleocene Agathis species from Patagonia. No previous phylo...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1127
更新日期:2018-08-01 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
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200028
更新日期:2012-09-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1300027
更新日期:2013-08-01 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.1300460
更新日期:2014-07-01 00:00:00
abstract::Sequence data from the intron and spacer of the trnL-F chloroplast region elucidate the phylogenetic relationships of the tribe Diseae (Orchidoideae: Orchidaceae). Within Diseae, 41 species of Disa, two of Brownleea, three of Satyrium, and two of Corycium were included, with five species of Habenaria sensu lato (Orchi...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-11-01 00:00:00
abstract::Temporal and demographic aspects of the growth of Botrychium gallicomontanum and B. mormo were studied for 2 yr. A total of 219 B. gallicomontanum and 412 B. mormo plants were monitored in a prairie and maple-basswood forest, respectively. Growth events were divided into four stages: leaf emergence, leaf separation, s...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.10.1624
更新日期:2002-10-01 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
abstract:UNLABELLED: PREMISE OF THE STUDY:Taxonomic groups have often been recognized on the basis of geographic distinctions rather than accurately representing evolutionary relationships. This has been particularly true for temperate and tropical members from the same family. Polygonaceae exemplifies this problem, wherein th...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000022
更新日期:2010-08-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1300269
更新日期:2014-04-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.12.2013
更新日期:2004-12-01 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
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1991-01-01 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
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更新日期:2007-08-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500156
更新日期:2015-08-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.3.377
更新日期:2003-03-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00
abstract::Perennial crops represent important fresh and processed food sources worldwide, but advancements in breeding perennials are often impeded due to their very nature. The perennial crops we rely on most for food take several years to reach production maturity and require large spaces to grow, which make breeding new cult...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400143
更新日期:2014-10-01 00:00:00
abstract::The direct and indirect effects of vegetative herbivory on the mating system of Impatiens capensis were analyzed through a survey of herbivory in natural I. capensis populations and manipulation of leaf damage in the field. Across 10 wild populations of I. capensis proportion of cleistogamous flowers had a significant...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.7.1046
更新日期:2004-07-01 00:00:00
abstract:PREMISE OF THE STUDY:The evolution of metal tolerance in plants is an important model for studies of adaptation to environment, population genetics, and speciation. Here, we investigated nickel tolerance in the North American serpentine endemic Caulanthus amplexicaulis var. barbarae in comparison with its nonserpentine...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200382
更新日期:2012-11-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400527
更新日期:2015-04-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000469
更新日期:2011-05-01 00:00:00
abstract::Paddy fields are one of the dominant anthropogenic sources of methane emission to the atmosphere, and the main passageway of methane from paddy soil is through the rice plant. However, the effect of aquatic weeds on methane emission from rice paddies has not been properly evaluated yet. Methane emission from weeded po...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-06-01 00:00:00
abstract:PREMISE OF THE STUDY:Microsatellite loci were developed in the endangered Pericopsis elata using a combination of low-cost procedures. METHODS AND RESULTS:Microsatellite isolation was performed simultaneously on three distinct species through a newly available procedure that associates multiplex microsatellite enrichm...
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