Abstract：
:Bumble bee pollinated Chamaecrista fasciculata provides pollen as the sole reward to its pollinators. Male sterility, expressed as an absence or nearly complete absence of pollen production, occurs in low frequency in populations of C. fasciculata. Here we describe experiments, using C. fasciculata, to examine frequently cited determinants of the spread and maintenance of male sterility: compensation and the genetic basis of male sterility. In addition, we examine the role the pollination system plays in determining the reproductive success of the male steriles. Seventeen populations in Maryland, Illinois, and Kansas were surveyed and found to range from 0 to 6% male sterility per population. An artificial population of male-sterile simulants and hermaphrodites was created to examine how the local frequency of nonrewarding male steriles might affect male-sterile female reproductive success. Male steriles performed equally poorly, with respect to seed production, whether surrounded by other male-sterile simulants or hermaphrodites. Compensation was examined by comparison of male steriles and hermaphrodites with respect to several reproductive and nonreproductive characters. Male steriles outperformed hermaphrodites in terms of nonreproductive biomass, but performed equally in terms of ovule number and produced many fewer flowers. The genetic basis of male sterility was examined by performing both intra- and interpopulational crosses of male steriles to hermaphrodites and indicate that male sterility is not purely cytoplasmic. The low frequency of male sterility in C. fasciculata populations may reflect reduced female reproductive success because of pollinator avoidance, lack of reproductive compensation, and a mode of inheritance that is not purely cytoplasmic.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Williams HL,Fenster CBsubject
Has Abstractpub_date
1998-09-01 00:00:00pages
1243-50issue
9eissn
0002-9122issn
1537-2197pii
85/9/1243journal_volume
85pub_type
杂志文章abstract：PREMISE OF THE STUDY:Despite being highly fertile and occupying a large geographic region, the North American heartleaf bittercress (Cardamine cordifolia; Brassicaceae) has a puzzling triploid-like chromosome number (2n = 3x = 24). As most triploids are sterile, we embarked on a detailed analysis of the C. cordifolia g...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1500452
更新日期：2016-07-01 00:00:00
abstract：:Species of Collinsia and Tonella, the two sister genera of self-compatible annuals that constitute tribe Collinsieae, show extensive variation in floral size and morphology and in patterns of stamen and style elongation during the life of the flower (anthesis). We used a nuclear ribosomal ITS phylogeny, independent co...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.89.1.37
更新日期：2002-01-01 00:00:00
abstract：:Seed mass is considered to be the least plastic component of reproductive yield. Yet, in invasive populations of garlic mustard, Alliaria petiolata, seed mass was highly variable (eightfold among populations, 2.5-7.5 fold within populations, two-threefold within individuals, and 1.4-1.8 fold within fruits). Variation ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2000-01-01 00:00:00
abstract：UNLABELLED: PREMISE OF THE STUDY:Specific leaf area (SLA) is a critical component of the leaf economics spectrum, and many functional leaf traits have been empirically demonstrated to covary with SLA. However, a complete understanding of how change in leaf size influences SLA has not yet emerged. • METHODS:To help de...
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：:When more pollen is present on stigmas than needed to fertilize all ovules, selection among pollen grains may occur due to effects of both pollen donors and maternal plants. We asked whether increasing plant age and flower age, two changes in maternal condition, altered the pattern of seed paternity after mixed pollin...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.94.3.409
更新日期：2007-03-01 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：10.1002/ajb2.1502
更新日期：2020-07-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1997-12-01 00:00:00
abstract：:The interaction between simulated cotyledon herbivory and interspecific competition was studied in a greenhouse experiment using two species of trees, Acer rubrum and Quercus palustris, which commonly invade abandoned agricultural fields. Herbivory treatments were applied as a gradient of cotyledon removal for A. rubr...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2000-12-01 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：UNLABELLED: PREMISE OF THE STUDY:A mixture of outcrossing and selfing is often observed in plant populations. Although mixed mating is ubiquitous, it has several potential evolutionary explanations. Mixed mating may be actively maintained by selection, passively determined by the pollination environment, or a transiti...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1000032
更新日期：2010-06-01 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：:Exotic plant species can threaten closely related native congeners through asymmetric hybridization and subsequent backcrossing, the process known as genetic assimilation. I explore the initial stages of this process in Taraxacum ceratophorum (Asteraceae), the native alpine dandelion, and the invasive apomict T. offic...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.91.5.656
更新日期：2004-05-01 00:00:00
abstract：PREMISE OF THE STUDY:We developed microsatellite loci for the biomass crop Miscanthus sinensis to investigate genetic diversity and population structure of M. sinensis and its closely related species. METHODS AND RESULTS:Fourteen microsatellite loci were identified from an enriched genomic library of M. sinensis and t...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1100040
更新日期：2011-07-01 00:00:00
abstract：PREMISE OF THE STUDY:Studies of natural genetic variation can elucidate the genetic basis of phenotypic variation and the past population structure of species. Our study species, Taxodium distichum, is a unique conifer that inhabits the flood plains and swamps of North America. Morphological and ecological differences ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1600046
更新日期：2016-11-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2000-08-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1372
更新日期：2019-11-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1352
更新日期：2019-09-01 00:00:00
abstract：:The mode of chloroplast DNA (cpDNA) inheritance was investigated in the genus Larrea (Zygophyllaceae) by polymerase chain reaction (PCR) amplification of cpDNA fragments using three pairs of chloroplast universal primers. A total of 20 F(1)s from interspecific crosses among five different taxa in the section Bifolium ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2000-10-01 00:00:00
abstract：:Fluorescence in situ hybridization (FISH) of a large-insert genomic clone, BAC 22B2, previously suggested that Sorghum bicolor (2n = 20) has the tetraploid architecture A(b)A(b)B(b)B(b). Here, we report on BAC 22B2 subclone pCEN38 (1047-bp insert) as related to sorghum and sugarcane. Mitotic FISH of six different subc...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2000-12-01 00:00:00
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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：PREMISE OF THE STUDY:Astragalus sect. Humillimi is distributed across the southwestern United States and contains two endangered taxa, A. cremnophylax var. cremnophylax and A. humillimus. The former was originally described from the South Rim of the Grand Canyon. Analysis of individuals discovered on the North Rim of t...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1157
更新日期：2018-10-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1400272
更新日期：2014-11-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1999-09-01 00:00:00
abstract：PREMISE:The ecological implications of hyperaccumulation have been investigated at the organismal level, but are poorly understood at the plant community level. Questions addressed here were: Does the presence of selenium (Se) hyperaccumulators affect Se distribution and concentration in their native soil, and do hyper...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1500
更新日期：2020-07-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.0900103
更新日期：2010-01-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1000159
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：
更新日期：1999-08-01 00:00:00
abstract：:A detailed study of ascomal morphology and development in Cercophora palmicola showed that ontogeny is ascohymeniaceous, giving rise to an ostiolate perithecium. Ascomal initials consist of a coiled ascogonium surrounded by several layers of hyphae whose cells become pseudoparenchymatous. The centrum of the young asco...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1999-06-01 00:00:00
abstract：:In a detailed analysis of how limited seed dispersal can create spatial structuring of genetic variation, several nuclear microsatellites were assayed in seedlings from two forests of Pinus strobus, one old growth (OG) and the other (second site, SS) logged in ca. 1900. By using loci with a large number of alleles and...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.91.4.549
更新日期：2004-04-01 00:00:00
