The four-celled female gametophyte of Illicium (Illiciaceae; Austrobaileyales): implications for understanding the origin and early evolution of monocots, eumagnoliids,and eudicots.

abstract：:A well-integrated plant shows extensive carbohydrate translocation through the plant body. Even in highly integrated plants, however, translocation patterns will be sectorial if vascular tissue restricts carbon movement to sectors along stems. Both integration and sectorial translocation patterns are sensitive to plan...

journal_title：American journal of botany

authors： Preston KA

更新日期：1998-12-01 00:00:00

abstract：PREMISE:The cosmopolitan and ecologically important grass subfamily Aristidoideae comprises the widely distributed genus Aristida (250-290 species), Stipagrostis (50 species, with an African-Asian distribution), and Sartidia (five species, Africa and Madagascar). The subfamily includes species with C(3) (Sartidia and a...

journal_title：American journal of botany

authors： Cerros-Tlatilpa R,Columbus JT,Barker NP

更新日期：2011-11-01 00:00:00

abstract：:Maximum parsimony analysis of DNA sequence data from the internal and external transcribed spacer (ITS and ETS) regions of 18S-26S nuclear ribosomal DNA and the 3' trnK intron of chloroplast DNA from over 60 populations of Lasthenia sect. Amphiachaenia yielded a well-supported tree showing that the most common species...

journal_title：American journal of botany

authors： Chan R,Baldwin BG,Ornduff R

更新日期：2002-07-01 00:00:00

abstract：:We examined the effect of inbreeding on fitness (through both male and female functions) and changes in self-fertility in the partially self-incompatible species Campanula rapunculoides. Individuals in natural populations of C. rapunculoides varied extensively in their strength of self-incompatibility (SI). We crossed...

journal_title：American journal of botany

authors： Good-Avila SV,Nagel T,Vogler DW,Stephenson AG

更新日期：2003-12-01 00:00:00

abstract：:Restriction fragment length polymorphism (RFLP) analysis of chloroplast (cp) DNA is a powerful tool for the study of microevolutionary processes in land plants, yet has not previously been applied to seaweed populations. We used cpDNA-RFLP, detected on Southern blots using labeled total plastid DNA, to search for intr...

journal_title：American journal of botany

authors： Wattier RA,Davidson AL,Ward BA,Maggs CA

更新日期：2001-07-01 00:00:00

abstract：PREMISE OF THE STUDY:Generic boundaries and infrageneric relationships among the charismatic temperate magnoliid Asarum sensu lato (Aristolochiaceae) have long been uncertain. Previous molecular phylogenetic analyses used either plastid or nuclear loci alone and varied greatly in their taxonomic implications for the ge...

journal_title：American journal of botany

authors： Sinn BT,Kelly LM,Freudenstein JV

更新日期：2015-05-01 00:00:00

abstract：:Studies of developmental stability can provide insights into the amount of genetic or environmental stress experienced by individuals or populations. In the present study, we used young plants of Acer platanoides (Norway maple) and Betula pendula (silver birch), two distantly related tree species with widely different...

journal_title：American journal of botany

authors： Black-Samuelsson S,Andersson S

更新日期：2003-08-01 00:00:00

abstract：:Recruitment and mortality of Spartina alterniflora tillers and culms were estimated from measurements of live standing crops at Wallops Island, Virginia. Stands of tall and medium form grass produced from 452 to 1,227 tillers m-2 yr-1 . Those tillered in spring lengthened into culms their first year, while those tille...

journal_title：American journal of botany

authors： Reidenbaugh TG

更新日期：1983-01-01 00:00:00

abstract：PREMISE OF THE STUDY:Populations of heterostylous species are characterized by two or three floral morphs with reciprocal positioning of stigmas and anthers. Theoretical models predict equal morph frequencies (isoplethy) when disassortative mating is prevalent in populations, but biased morph ratios may occur when vari...

journal_title：American journal of botany

authors： Ferrero V,Barrett SC,Rojas D,Arroyo J,Navarro L

更新日期：2017-01-01 00:00:00

abstract：:Soybean partial-female-sterile mutant 1 (PS-1) was recovered from a gene-tagging study. The objectives were to study the inheritance, linkage, allelism, and certain aspects of the reproductive biology of the PS-1 mutant. For inheritance and linkage tests, PS-1 was crossed to flower color mutant Harosoy-w4 and to chlor...

journal_title：American journal of botany

authors： Pereira T,Lersten N,Palmer R

更新日期：1997-06-01 00:00:00

abstract：:Many foliar pathogens require free water to germinate; therefore, disease pressure should favor plants that are able to repel water. For a suite of 18 sympatric clover species (Trifolium and Medicago, Fabaceae), we evaluated leaf traits affecting leaf wetness and susceptibility to infection by the fungal pathogen Stem...

journal_title：American journal of botany

authors： Bradley DJ,Gilbert GS,Parker IM

更新日期：2003-06-01 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

authors： Massatti R,Belus MT,Dowlatshahi S,Allan GJ

更新日期：2018-10-01 00:00:00

abstract：:A long-term survey (1990-2000) of pollination modes of 86 tree species was carried out at Kakachi, a mid-elevation wet forest site in southern Western Ghats, India. Observations were made on 86 tree species. This comprises 80% of the total arborescent species present in the site. Approximately 75% of these species wer...

journal_title：American journal of botany

authors： Devy MS,Davidar P

更新日期：2003-04-01 00:00:00

abstract：:In addition to vegetative remains, fertile remains from ten plants, representing seven distinct taxa whose size and complexity are much greater than most contemporaneous fossils, are reported from late Ludlow (Ludfordian) sediments of Bathurst Island in Nunavut, Canada. Evidence for the age of these beds is gathered f...

journal_title：American journal of botany

authors： Kotyk ME,Basinger JF,Gensel PG,de Freitas TA

更新日期：2002-06-01 00:00:00

abstract：PREMISE OF THE STUDY:A knowledge of pollen characters in early-diverging angiosperm lineages is essential for understanding pollen evolution and the role of pollen in angiosperm diversification. In this paper, we report and synthesize data on mature pollen and pollen ontogeny from all genera of Nymphaeales within a com...

journal_title：American journal of botany

authors： Taylor ML,Cooper RL,Schneider EL,Osborn JM

更新日期：2015-10-01 00:00:00

abstract：PREMISE OF THE STUDY:The species boundaries of wild and cultivated potatoes are controversial, with most of the taxonomic problems in the cultivated potato clade. We here provide the first in-depth phylogenetic study of the cultivated potato clade to explore possible causes of these problems. METHODS:We examined 131 d...

journal_title：American journal of botany

authors： Spooner DM,Ruess H,Arbizu CI,Rodríguez F,Solís-Lemus C

更新日期：2018-01-01 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：PREMISE:Despite the fast pace of exploration of the patterns and processes influencing Neotropical plant hyperdiversity, the taxa explored are mostly from large groups that are widely distributed, morphologically diverse, or economically important. Vochysiaceae is an example of an undersampled taxon, providing an excel...

journal_title：American journal of botany

authors： Gonçalves DJP,Shimizu GH,Ortiz EM,Jansen RK,Simpson BB

更新日期：2020-07-01 00:00:00

abstract：:It is often suggested that traits will be integrated, either because of pleiotropy or because natural selection may favor suites of integrated traits. Plant responses to different environments can provide evidence of such integration. We grew Mercurialis annua plants in high-density stands in high irradiance, in neutr...

journal_title：American journal of botany

authors： Sleeman JD,Dudley SA,Pannell JR,Barrett SC

更新日期：2002-09-01 00:00:00

abstract：:The phenotype of maize plants that are homozygous recessive for the nuclear gene iojap is commonly an "anemic," grainy green appearance accompanied by white leaf stripes, white leaf margins, and reduced growth. In plants in which the iojap effect is occurring (homozygous ij/ij), we find affected tissue varies in exten...

journal_title：American journal of botany

authors： Coe EH Jr,Thompson D,Walbot V

更新日期：1988-05-01 00:00:00

abstract：:Detailed investigations on Lower Cretaceous Ephedra L. fossils (Gnetopsida) reveal morphological characters similar to those of extant Ephedra rhytidosperma Pachomova, including articulate branches with many fine longitudinal striations, a dichasial branching pattern, uni- or bi-ovulate cones with paired bracts, cones...

journal_title：American journal of botany

authors： Yang Y,Geng BY,Dilcher DL,Chen ZD,Lott TA

更新日期：2005-02-01 00:00:00

abstract：PREMISE OF THE STUDY:Microsatellite primers were developed in the native legume tree Anadenanthera colubrina var. cebil to study the genetic diversity and genetic structure in natural populations in Argentina. METHODS AND RESULTS:Nine microsatellite markers were identified using a genomic library enriched for tandemly...

journal_title：American journal of botany

authors： Barrandeguy ME,Prinz K,García MV,Finkeldey R

更新日期：2012-09-01 00:00:00

abstract：PREMISE OF THE STUDY:Nutrient resorption is essential for plant nutrient conservation. Large-bodied plants potentially have large nutrient sink pools and high nutrient flux. Whether and how nutrient resorption can be regulated by plant size and biomass allocation are yet unknown. METHODS:Using the herbaceous plant Ama...

journal_title：American journal of botany

authors： Peng H,Yan Z,Chen Y,Zhao X,Han W

更新日期：2019-03-01 00:00:00

abstract：:Nuphar comprises 13 species of aquatic perennials distributed in the temperate Northern Hemisphere. The European species N. lutea and N. pumila in Norway, the Netherlands, and Germany are pollinated by bees and flies, including apparent Nuphar specialists. This contrasts with reports of predominant beetle pollination ...

journal_title：American journal of botany

authors： Lippok B,Gardine AA,Williamson PS,Renner SS

更新日期：2000-06-01 00:00:00

abstract：:In rainforests, trunk size, strength, crown position, and geometry of a tree affect light interception and the likelihood of mechanical failure. Allometric relationships of tree diameter, wood density, and crown architecture vs. height are described for a diverse range of rainforest trees in Brunei, northern Borneo. T...

journal_title：American journal of botany

authors： Osunkoya OO,Omar-Ali K,Amit N,Dayan J,Daud DS,Sheng TK

更新日期：2007-12-01 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

authors： Villarreal JC,Forrest LL,McFarland K,Goffinet B

更新日期：2012-03-01 00:00:00

abstract：:Microscopic structures (petrofilaments) may develop during palynological laboratory processing procedures that are superficially similar to secondary wall thickenings and elaters. These filaments form from angular bodies that resemble fungal spores and resin bodies. The angular bodies are a type of hydrocarbon called ...

journal_title：American journal of botany

authors： Graham A,Wood GD,Elsik WC,Speed RC

更新日期：2000-05-01 00:00:00

abstract：:We examined the function of floral traits associated with buzz pollination through studies of Rhexia virginica (Melastomataceae) in the Muskoka region of Ontario, Canada. Controlled pollinations demonstrated that the species is self-compatible, but dependent on insects for pollen transfer. Bumble bees made 82 and 90% ...

journal_title：American journal of botany

authors： Larson BM,Barrett SC

更新日期：1999-04-01 00:00:00

abstract：:In the alpine landscape most plant populations are spatially isolated due to extreme patchiness and strong natural fragmentation. We used RAPD-PCR (randomly amplified polymorphic DNA polymerase chain reaction) for a study of the genetic diversity within and among 20 populations of Geum reptans, an outcrossing clonal p...

journal_title：American journal of botany

authors： Pluess AR,Stöcklin J

更新日期：2004-12-01 00:00:00

abstract：:Up to 22% of plant species are the result of breeding among species-hybridization-directly conflicting with the prediction that hybrids, compared to parental species, are intermediate in character and of low fitness and little consequence. Few studies, however, have compared the fitness of hybrids and parental species...

journal_title：American journal of botany

authors： Tierney DA,Wardle GM

更新日期：2008-02-01 00:00:00