Comparative analysis of late floral development and mating-system evolution in tribe Collinsieae (Scrophulariaceae s.l.).

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：: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

authors： Meiners SJ,Handel SN

更新日期：2000-12-01 00:00:00

abstract：PREMISE OF THE STUDY:Autopolyploidy, or whole-genome duplication within a species, leads to closely related cytotypes in one geographic location. One hypothesized mechanism by which autopolyploids become established is climatic niche divergence from their diploid progenitor. Here we tested this hypothesis in diploid, t...

journal_title：American journal of botany

authors： Gaynor ML,Marchant DB,Soltis DE,Soltis PS

更新日期：2018-10-01 00:00:00

abstract：:Hybridization and introgression play important roles in plant evolution, and their occurrence on the oceanic islands provides good examples of plant speciation and diversification. Restriction fragment length polymorphisms (RFLPs) and trnL (UAA) 3'exon-trnF (GAA) intergenic spacer (IGS) sequences of chloroplast DNA (c...

journal_title：American journal of botany

authors： Setoguchi H,Watanabe I

更新日期：2000-06-01 00:00:00

abstract：PREMISE:Variation in seedling emergence timing is considered adaptive over the long term in wild populations, but early emergence can result in a fitness advantage. To explore the adaptive significance of seedling emergence timing, it should be studied under realistic conditions and in the context of other traits that ...

journal_title：American journal of botany

authors： Mercer KL,Alexander HM,Snow AA

更新日期：2011-06-01 00:00:00

abstract：PREMISE OF THE STUDY:Previous studies have shown that polyploidy has pronounced effects on photosynthesis. Most of these studies have focused on synthetic or recently formed autopolyploids, and comparatively little is known about the integrated effects of natural allopolyploidy, which involves hybridity and genome doub...

journal_title：American journal of botany

authors： Coate JE,Luciano AK,Seralathan V,Minchew KJ,Owens TG,Doyle JJ

更新日期：2012-01-01 00:00:00

abstract：:Terrestrial plant leaves are complex structures of composite materials. Resistance to fracture is achieved by a number of mechanisms, which operate at the molecular, cell, tissue, and structural levels. Leaves of dicots have different venation patterns and cell wall volume fractions from those of grasses, and conseque...

journal_title：American journal of botany

authors： Sanson G

更新日期：2006-10-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Despite the ecological, economic, and cultural importance of the palm Mauritia flexuosa in Amazonia, knowledge of its reproductive biology is scarce. Previous observations of this species suggested beetles as the probable pollinator, but experimental work to confirm this hypothesis was...

journal_title：American journal of botany

authors： Khorsand Rosa R,Koptur S

更新日期：2013-03-01 00:00:00

abstract：:Cacti are a large and diverse group of stem succulents predominantly occurring in warm and arid North and South America. Chloroplast DNA sequences of the trnK intron, including the matK gene, were sequenced for 70 ingroup taxa and two outgroups from the Portulacaceae. In order to improve resolution in three major grou...

journal_title：American journal of botany

authors： Nyffeler R

更新日期：2002-02-01 00:00:00

abstract：:Molecular phylogenetic studies of seven plastid DNA regions were used to resolve circumscriptions at generic and infrageneric levels in subfamily Tillandsioideae of Bromeliaceae. One hundred and ten tillandsioid samples were analyzed, encompassing 10 genera, 104 species, and two cultivars. Two species of Bromelioideae...

journal_title：American journal of botany

authors： Barfuss MH,Samuel R,Till W,Stuessy TF

更新日期：2005-02-01 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：PREMISE OF THE STUDY:We developed the first set of microsatellite markers for the passion fruit, Passiflora cincinnata, to provide tools for further study of its genetic diversity and to support current conservation and genetic studies. METHODS AND RESULTS:We used a microsatellite-enriched library approach to isolate ...

journal_title：American journal of botany

authors： Cerqueira-Silva CB,Santos ES,Souza AM,Mori GM,Oliveira EJ,Corrêa RX,Souza AP

更新日期：2012-04-01 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

authors： Brock MT

更新日期：2004-05-01 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：PREMISE OF THE STUDY:During the interactions between a parasitic plant and its host, the parasite affects its host morphologically, anatomically, and physiologically, yet there has been little focus on the effect of hosts on the parasite. Here, the functional interactions between the hemiparasitic mistletoe Psittacanth...

journal_title：American journal of botany

authors： Cocoletzi E,Angeles G,Ceccantini G,Patrón A,Ornelas JF

更新日期：2016-06-01 00:00:00

abstract：PREMISE OF THE STUDY:Fern spores are unicellular and haploid, making them a potential model system to study factors that regulate lifespan and mechanisms of aging. Aging rates of nongreen spores were measured to compare longevity characteristics among diverse fern species and test for orthodox response to storage tempe...

journal_title：American journal of botany

authors： Ballesteros D,Estrelles E,Walters C,Ibars AM

更新日期：2012-04-01 00:00:00

abstract：:The geographic distribution of diploid and tetraploid cytotypes and cpDNA haplotypes throughout the entire range of Aucuba japonica was investigated. We measured relative genome size using flow cytometry and sequenced two cpDNA intergenic regions, atpB-rbcL and psbA-trnH (GUG). Two haplotypes include both diploids and...

journal_title：American journal of botany

authors： Ohi T,Kajita T,Murata J

更新日期：2003-11-01 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：:Size, allometry, and mechanical design were measured for trees of three canopy species in a tropical rain forest in French Guiana. Mechanical design was expressed as the safety factor, using the elastic-stability model, and the wind resistance factor, using the constant-stress model. Changes with ontogeny were describ...

journal_title：American journal of botany

authors： Sterck F,Bongers F

更新日期：1998-02-01 00:00:00

abstract：:Isozymatic data taken from 67 Guatemalan collections of maize were subjected to numerical taxonomic analyses to elucidate systematic relationships among the 19 maize races and subraces described for Guatemala by Wellhausen et al. As with Bolivian and Mexican races, isozymatic variation in Guatemalan maize was strongly...

journal_title：American journal of botany

authors： Bretting PK,Goodman MM,Stuber CW

更新日期：1990-02-01 00:00:00

abstract：:Many plant species contain populations with more than one polyploid cytotype, but little is known of the mechanisms maintaining several cytotypes in a population. Andropogon gerardii cytotypes were compared to evaluate different models of autopolyploid cytotype coexistence. The enneaploid (90 chromosome, 9x) cytotype ...

journal_title：American journal of botany

authors： Keeler KH,Davis GA

更新日期：1999-07-01 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：PREMISE OF THE STUDY:Identifying recently diverged taxa can be useful for studying the process of speciation. Ipomoea lacunosa and I. cordatotriloba, along with a putative homoploid hybrid, I. ×leucantha, are closely related taxa, which are promising for investigating the early stages of speciation. The objectives of t...

journal_title：American journal of botany

authors： Duncan TM,Rausher MD

更新日期：2013-11-01 00:00:00

abstract：PREMISE OF THE STUDY:Climate change models for California predict a warmer, drier future, potentially resulting in shorter growing seasons. If phenotypic differences between closely related species currently distributed across a moisture and temperature gradient represent adaptations to their abiotic environment, then ...

journal_title：American journal of botany

authors： Schneider HE,Mazer SJ

更新日期：2016-01-01 00:00:00

abstract：:Scaling relationships among photosynthetic rate, foliar nutrient concentration, and leaf mass per unit area (LMA) have been observed for a broad range of plants. Leaf traits of the carnivorous pitcher plant Darlingtonia californica, endemic to southern Oregon and northern California, USA, differ substantially from the...

journal_title：American journal of botany

authors： Ellison AM,Farnsworth EJ

更新日期：2005-07-01 00:00:00

abstract：PREMISE OF THE STUDY:Plant communities may be influenced by toxic secondary metabolites or enhanced plant growth from plant-symbiont interactions. The C:N hypothesis predicts that carbon or nitrogen constrains plant secondary metabolite production, but it does not consider compounds produced by plant symbionts. Locowee...

journal_title：American journal of botany

authors： Delaney KJ,Klypina N,Maruthavanan J,Lange C,Sterling TM

更新日期：2011-12-01 00:00:00

abstract：:We examined the effects of size and spatial isolation of fens on the isozyme variability of 17 populations of Swertia perennis. This long-lived perennial is a locally abundant fen specialist in Switzerland, where wetlands have been strongly fragmented. Isozyme variability was comparable to other outcrossing plants (A ...

journal_title：American journal of botany

authors： Lienert J,Fischer M,Schneller J,Diemer M

更新日期：2002-05-01 00:00:00

abstract：:Nuclear and chloroplast DNA variation was assayed for two populations of Louisiana irises (Bayou Teche and Young's Coulee) that demonstrated extreme morphological variation and for a sample of the putative hybrid species, Iris nelsonii. The genetic markers examined in this analysis were diagnostic for either Iris fulv...

journal_title：American journal of botany

authors： Arnold ML

更新日期：1993-05-01 00:00:00

abstract：:Very little is known regarding how repetitive elements evolve inpolyploid organisms. Here we address this subject by fluorescent insitu hybridization (FISH) of 20 interspersed repetitive elements tometaphase chromosomes of the cotton AD-genome tetraploid Gossypiumhirsutum and its putative A- and D-genome diploid ances...

journal_title：American journal of botany

authors： Hanson R,Zhao XP,Islam-Faridi MN,Paterson A,Zwick M,Crane C,McKnight T,Stelly D,Price HJ

更新日期：1998-10-01 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

authors： Ikezaki Y,Suyama Y,Middleton BA,Tsumura Y,Teshima K,Tachida H,Kusumi J

更新日期：2016-11-01 00:00:00