Phylogeny of the Neotropical Alibertia group (Rubiaceae), with emphasis on the genus Alibertia, inferred from ITS and 5S ribosomal DNA sequences.

abstract：UNLABELLED:• PREMISE OF THE STUDY:The question why leaf dimensions vary so much between species has long puzzled ecologists. Presumably, variation arises from selective forces acting on leaf function but which selective forces and which leaf functions? This investigation assesses the consistency of divergence in plant...

journal_title：American journal of botany

authors： Tozer WC,Rice B,Westoby M

更新日期：2015-03-01 00:00:00

abstract：PREMISE OF THE STUDY:Conifers are an important living seed plant lineage with an extensive fossil record spanning more than 300 million years. The group therefore provides an excellent opportunity to explore congruence and conflict between dated molecular phylogenies and the fossil record. METHODS:We surveyed the curr...

journal_title：American journal of botany

authors： Leslie AB,Beaulieu J,Holman G,Campbell CS,Mei W,Raubeson LR,Mathews S

更新日期：2018-09-01 00:00:00

abstract：:We developed an improved cytological protocol for producing high quality, light microscope images of plant meiotic chromosomes. Because the technique works on species with small genomes and thick microsporocyte cell walls, it should be useful for studying the wild relatives of Arabidopsis and other eudicots with small...

journal_title：American journal of botany

authors： Stronghill PE,Hasenkampf CA

更新日期：2007-12-01 00:00:00

abstract：PREMISE OF THE STUDY:Permineralization provides the most faithful known mode of three-dimensional preservation of the morphology and cellular anatomy of fossil plants. Standard optical microscopic documentation of such structures can provide only an approximation of their true three-dimensional form and is incapable of...

journal_title：American journal of botany

authors： Shi CS,Schopf JW,Kudryavtsev AB

更新日期：2013-08-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Microsatellite markers were developed in an alpine plant endemic to the Qinghai-Tibetan Plateau, Androsace tapete, to investigate its spatial genetic structure, gene flow, and mating patterns. • METHODS AND RESULTS:Using the combined biotin capture method, 16 microsatellite primer set...

journal_title：American journal of botany

authors： Zeng L,Li Z,Tashi T,Chen J,Zhong Y,Geng Y

更新日期：2010-10-01 00:00:00

abstract：PREMISE OF THE STUDY:Species differ in their temperature germination niche. Populations of a species may similarly differ across the distribution range of the species. Anticipating the impacts of climate variability and change requires understanding the differential sensitivity to germination temperature among and with...

journal_title：American journal of botany

authors： Chamorro D,Luna B,Moreno JM

更新日期：2017-01-01 00:00:00

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

authors： Smith SD,Goldberg EE

更新日期：2015-07-01 00:00:00

abstract：PREMISE OF THE STUDY:Climate cycles of the Quaternary have impacted plants at a global scale, leaving behind a complex genetic legacy. Species of the northern Rocky Mountains of North America were exposed to more uniform glacial patterns than the central and southern ranges, where synergistic relationships between temp...

journal_title：American journal of botany

authors： Fuller RS,McGlaughlin ME

更新日期：2019-03-01 00:00:00

abstract：PREMISE OF THE STUDY:Pollinator shifts have been implicated as a driver of divergence in angiosperms. We tested the hypothesis that there was a transition from bird- to butterfly pollination in the African genus Clivia (Amaryllidaceae) and investigated how floral traits may have been either modified or retained during ...

journal_title：American journal of botany

authors： Kiepiel I,Johnson SD

更新日期：2014-01-01 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

authors： Adams NF,Collinson ME,Smith SY,Bamford MK,Forest F,Malakasi P,Marone F,Sykes D

更新日期：2016-09-01 00:00:00

abstract：:The American chestnut (Castanea dentata; Fagaceae) was a dominant canopy tree in the Appalachian Mountains of North America. Since the introduction of the chestnut blight fungus (Cryphonectria parasitica; Valsaceae) in America, the American chestnut has been reduced to a predominantly clonal, understory species. Our o...

journal_title：American journal of botany

authors： Stilwell KL,Wilbur HM,Werth CR,Taylor DR

更新日期：2003-02-01 00:00:00

abstract：:We demonstrated that "orchid mycorrhiza," a specialized mycorrhizal type, appeared in the common ancestor of the largest plant family Orchidaceae and that the fungal partner shifted from Glomeromycota to a particular clade of Basidiomycota in association with this character evolution. Several unique mycorrhizal charac...

journal_title：American journal of botany

authors： Yukawa T,Ogura-Tsujita Y,Shefferson RP,Yokoyama J

更新日期：2009-11-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Phenolic compounds exuded by roots have been implicated in allelopathic interactions among plants. Root enzymes that destroy phenolics may protect plants against allelopathic inhibition and thus may aid in invasiveness. Phenolic-degrading enzymes are chiefly found in aboveground plant ...

journal_title：American journal of botany

authors： Holzapfel C,Shahrokh P,Kafkewitz D

更新日期：2010-07-01 00:00:00

abstract：:Propagule banks are assumed to be able to store considerable genetic variability. Bryophyte populations are expected to rely more heavily on stored propagules than those of seed plants due to the vulnerability of the haploid gametophyte. This reliance has important implications for the genetic structure and evolutiona...

journal_title：American journal of botany

authors： Hock Z,Szövényi P,Schneller JJ,Tóth Z,Urmi E

更新日期：2008-05-01 00:00:00

abstract：:Tribe Macadamieae (91 spp., 16 genera; Proteaceae) is widespread across the southern hemisphere on all major fragments of Gondwana except New Zealand and India. Macadamia is cultivated outside its natural range as a "nut" crop (notably in Hawaii, where it is the principal orchard crop). We sampled seven DNA regions an...

journal_title：American journal of botany

authors： Mast AR,Willis CL,Jones EH,Downs KM,Weston PH

更新日期：2008-07-01 00:00:00

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 surf...

journal_title：American journal of botany

authors： Johnson DM,Smith WK,Vogelmann TC,Brodersen CR

更新日期：2005-09-01 00:00:00

abstract：UNLABELLED:• PREMISE OF THE STUDY:Adansonia digitata L. is one of the most important indigenous fruit trees of mainland Africa. Despite its significance for subsistence and income generation of local communities, little is known about the genetic and morphological variability of East African populations of A. digitata...

journal_title：American journal of botany

authors： Wiehle M,Prinz K,Kehlenbeck K,Goenster S,Mohamed SA,Finkeldey R,Buerkert A,Gebauer J

更新日期：2014-09-01 00:00:00

abstract：:We used isozymes (16 loci in 11 enzymatic systems) from Laelia speciosa, an endemic and endangered epiphytic orchid of Mexico, to assess the genetic diversity and population genetic structure in nine populations distributed along its geographic range, as well as to detect those populations that are genetically unique ...

journal_title：American journal of botany

authors： Avila-Díaz I,Oyama K

更新日期：2007-02-01 00:00:00

abstract：:The genus Rosa has a complex evolutionary history caused by several factors, often in conjunction: extensive hybridization, recent radiation, incomplete lineage sorting, and multiple events of polyploidy. We examined the applicability of AFLP markers for reconstructing (species) relationships in Rosa, using UPGMA clus...

journal_title：American journal of botany

authors： Koopman WJ,Wissemann V,De Cock K,Van Huylenbroeck J,De Riek J,Sabatino GJ,Visser D,Vosman B,Ritz CM,Maes B,Werlemark G,Nybom H,Debener T,Linde M,Smulders MJ

更新日期：2008-03-01 00:00:00

abstract：PREMISE:Outcomes of species interactions, especially mutualisms, are notoriously dependent on environmental context, and environments are changing rapidly. Studies have investigated how mutualisms respond to or ameliorate anthropogenic environmental changes, but most have focused on nutrient pollution or climate change...

journal_title：American journal of botany

authors： O'Brien AM,Yu ZH,Luo DY,Laurich J,Passeport E,Frederickson ME

更新日期：2020-02-01 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

authors： Theim TJ,Shirk RY,Givnish TJ

更新日期：2014-07-01 00:00:00

abstract：:Xylem of the orchids studied provided unusually favorable material to demonstrate how conductive tissue evolves in monocotyledons. In the end walls of tracheary elements of many Orchidaceae, remnants of pit membranes were observed with scanning electron microscopy and minimally destructive methods. The full range from...

journal_title：American journal of botany

authors： Carlquist S,Schneider EL

更新日期：2006-07-01 00:00:00

abstract：PREMISE OF THE STUDY:Endophytic fungi are common inhabitants of cool-season grasses that can affect host growth and reproduction. One prerequisite for the expected coevolution between symbionts is that there exist variable effects of the endosymbiont on its host in different environments. Here, the impact of endophytes...

journal_title：American journal of botany

authors： Cheplick GP

更新日期：2011-05-01 00:00:00

abstract：PREMISE OF THE STUDY:Herbivory can affect a plant's fitness in a variety of ways, including modifying the biotic interactions of the plant. In particular, when herbivory influences floral display, we hypothesize that pollinator visitation will be altered accordingly. Here we studied the indirect effects of feeding by t...

journal_title：American journal of botany

authors： Russell-Mercier JL,Sargent RD

更新日期：2015-05-01 00:00:00

abstract：:Eight ecosystems that were present in the Cretaceous about 100 Ma (million years ago) in the New World eventually developed into the 12 recognized for the modern Earth. Among the forcing mechanisms that drove biotic change during this interval was a decline in global temperatures toward the end of the Cretaceous, augm...

journal_title：American journal of botany

authors： Graham A

更新日期：2011-03-01 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

authors： Véliz D,Gauci R,Bustamante RO

更新日期：2012-09-01 00:00:00

abstract：PREMISE OF THE STUDY:Male-biased herbivory in dioecious species is expected as a consequence of selection for increased resistance (reduced attack) in the sex with higher reproductive costs-females. Empirical support of this prediction is taxonomically restricted and fraught with exceptions. Phenological changes in res...

journal_title：American journal of botany

authors： Buckley NE,Avila-Sakar G

更新日期：2013-02-01 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

authors： Burke JM,Sanchez A,Kron K,Luckow M

更新日期：2010-08-01 00:00:00

abstract：PREMISE OF THE STUDY:The evolutionary shift from radial to bilateral symmetry in flowers is generally associated with the evolution of low flower-size variation. This phenomenon supports the hypothesis that the lower size variation in bilateral flowers can be attributed to low pollinator diversity. In this study, we pr...

journal_title：American journal of botany

authors： Nikkeshi A,Kurimoto D,Ushimaru A

更新日期：2015-12-01 00:00:00

abstract：PREMISE OF THE STUDY:Seabirds often cause significant changes to soil properties, and seabird-dominated systems often host unique plant communities. This study experimentally (1) examined species-specific responses to seabird guano gradients, (2) considered the role that differential functional traits among species pla...

journal_title：American journal of botany

authors： Young HS,McCauley DJ,Dirzo R

更新日期：2011-02-01 00:00:00