Abstract:
:Genetic diversity at variable-number-tandem-repeat (VNTR) loci was examined in the common cattail, Typha latifolia (Typhaceae), using three synthetic DNA probes composed of tandemly repeated "core" sequences (GACA, GATA, and GCAC). The principal objectives of this investigation were to determine whether: (1) the previously reported almost complete lack of polymorphism at allozyme loci in this species was indicative of a reduced amount of genetic diversity at VNTR loci as well; (2) VNTR markers were informative about possible clonal propagation; and (3) significant differences in genetic structure of sampling sites were associated with differences in environmental levels of pollutants at those sites. Previously, widespread sampling across the eastern United States, surveying across ten allozyme loci, has detected only two genotypes, involving a difference at a single locus, among 104 populations. In this study, the amount of genetic diversity detected at VNTR loci: (1) among ramets (N = 40; 40 genotypes detected) collected at ∼8-km intervals along a 320-km transect; (2) among ramets (N = 220; 117 genotypes detected) from five study sites separated by 50-3000 m; and (3) even among ramets within each study site [N = 44 per site; from 13 to 34 genotypes detected per site (270 m(2))] exceeds that previously found in those more geographically widespread allozyme surveys. Among the 260 ramets analyzed here, the mean number of bands scored per individual was 48.61 (SD = 2.80). Mean genetic similarity among ramets collected along the 320-km transect was 0.91, which was within the range of mean genetic similarity within the five study sites (range: 0.89-0.95). Among the five study sites, 61% of the samples analyzed appeared to be clonal ramets, with up to 12 clones detected for 44 ramets sampled within a site. Clones grew intermingled and ranged up to 39 m in extent. Permutation tests of genetic similarity revealed significant genetic differentiation between each of the five study sites. Consistent with the previous allozyme studies, T. latifolia was characterized by extremely low genetic variation relative to levels of polymorphism detected at VNTR loci in other plant species. Estimated heterozygosity among ramets along the 320-km transect ranged from 0.11 to 0.13, while that within the five study sites ranged from 0.05 to 0.12. Estimates of F(st) (0.32-0.41) also indicated considerable genetic subdivision among these stands. Significantly higher genetic diversity was detected at the two study sites that chemistry and toxicity data indicate to be the most severely impacted by pollutants. Although this correlation does not establish cause and effect, the results of this study indicate that the analysis of genetic diversity at VNTR loci may be a useful tool for monitoring anthropogenic-induced changes in the genetic structure of natural populations of plants.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Keane B,Pelikan S,Toth GP,Smith MK,Rogstad SHsubject
Has Abstractpub_date
1999-09-01 00:00:00pages
1226-38issue
9eissn
0002-9122issn
1537-2197pii
86/9/1226journal_volume
86pub_type
杂志文章abstract::Koch et al. (Nature 428: 851-854) measured various parameters that were thought to limit the height of Sequoia sempervirens from northern California and concluded that the maximum height for this species is 122-130 m because within this range: (1) Irreversible embolism formation was proposed to occur when the xylem pr...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800144
更新日期:2009-02-01 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
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journal_title:American journal of botany
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doi:10.3732/ajb.94.9.1534
更新日期:2007-09-01 00:00:00
abstract:PREMISE OF THE STUDY:The ecological and evolutionary significance of natural epigenetic variation (i.e., not based on DNA sequence variants) variation will depend critically on whether epigenetic states are transmitted from parents to offspring, but little is known on epigenetic inheritance in nonmodel plants. METHODS...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1074
更新日期:2018-04-01 00:00:00
abstract::The balance between clonal and sexual reproduction can vary widely among plant populations, and the extent of clonality may be influenced by the combined effects of historical land use and variation in environmental conditions. We investigated patterns of clonal spread in five Trillium cuneatum populations, two in the...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.2007159
更新日期:2008-10-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-03-01 00:00:00
abstract::The amplified fragment length polymorphism (AFLP) method was used to evaluate genetic diversity and to assess genetic relationships within the section Mentha in order to clarify the taxonomy of several interspecific mint hybrids with molecular markers. To this end, genetic diversity of 62 Mentha accessions from differ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.12.2017
更新日期:2002-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.4.549
更新日期:2004-04-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.6.857
更新日期:2003-06-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1049
更新日期:2018-03-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-03-01 00:00:00
abstract:PREMISE OF THE STUDY:Fossilized seeds similar to Cissus (Vitaceae) have been recognized from the Miocene of Kenya, though some were previously assigned to the Menispermaceae. We undertook a comparative survey of extant African Cissus seeds to identify the fossils and consider their implications for the evolution and bi...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600177
更新日期:2016-09-01 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
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1061
更新日期:2018-03-01 00:00:00
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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
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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
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.12.1951
更新日期:2007-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.12.1748
更新日期:2006-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.2.231
更新日期:2005-02-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900224
更新日期:2010-02-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1031
更新日期:2018-02-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.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,评审
doi:10.3732/ajb.1400024
更新日期:2014-05-01 00:00:00
abstract:PREMISE OF THE STUDY:Over one-third of the native flowering plant species in the Hawaiian Islands are listed as federally threatened or endangered. Lack of sufficient pollination could contribute to reductions in populations, reproduction, and genetic diversity among these species but has been little studied. METHODS:...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1233
更新日期:2019-02-01 00:00:00
abstract::We launched imbibed seeds and seedlings of Zea mays into outer space aboard the space shuttle Columbia to determine the influence of microgravity on 1) root-cap regeneration, and 2) the distribution of amyloplasts and endoplasmic reticulum (ER) in the putative statocytes (i.e., columella cells) of roots. Decapped roo...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1987-01-01 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::Inferring basal relationships among vascular plants poses a major challenge to plant systematists. The divergence events that describe these relationships occurred long ago and considerable homoplasy has since accrued for both molecular and morphological characters. A potential solution is to examine phylogenetic anal...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-10-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500052
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.95.3.353
更新日期:2008-03-01 00:00:00