A Late Cretaceous Piper (Piperaceae) from Colombia and diversification patterns for the genus.

abstract：:We transplanted Nuphar variegata with submersed leaves only into natural lake sediments in pH-, [CO(2)]-, depth-, and temperature-controlled greenhouse tanks to test the hypotheses that more fertile sediment, lower free [CO(2)], and shallower depth would all stimulate the development of floating leaves. Sediment highe...

journal_title：American journal of botany

authors： Titus JE,Gary Sullivan P

更新日期：2001-08-01 00:00:00

abstract：:Cladistic analyses of plastid DNA sequences rbcL and trnL-F are presented separately and combined for 48 genera of Amaryllidaceae and 29 genera of related asparagalean families. The combined analysis is the most highly resolved of the three and provides good support for the monophyly of Amaryllidaceae and indicates Ag...

journal_title：American journal of botany

authors： Meerow AW,Fay MF,Guy CL,Li QB,Zaman FQ,Chase MW

更新日期：1999-09-01 00:00:00

abstract：:The recent consensus that Amborellaceae, Nymphaeales, and Austrobaileyales form the three earliest-diverging lineages of angiosperms has led comparative biologists to reconsider the origin and early developmental evolution of the angiosperm seven-celled/eight-nucleate (Polygonum-type) female gametophyte. Illicium mexi...

journal_title：American journal of botany

authors： Williams JH,Friedman WE

更新日期：2004-03-01 00:00:00

abstract：PREMISE OF THE STUDY:The genus Hoya (Apocynaceae; Asclepiadoideae) is characterized by a set of complex floral characters unique among the asclepiads, but their role in pollination is poorly understood. Here, we report a new mechanism of asclepiad pollination in the wax plant Hoya carnosa: the pollinaria are transferre...

journal_title：American journal of botany

authors： Mochizuki K,Furukawa S,Kawakita A

更新日期：2017-06-01 00:00:00

abstract：PREMISE OF THE STUDY:Expressed sequence tag (EST)-derived microsatellite markers were developed for Elaeocarpus photiniifolia, an endemic taxon of the Bonin Islands. METHODS AND RESULTS:Initially, a complementary DNA (cDNA) library was constructed by de novo pyrosequencing of total RNA extracted from a seedling. A tot...

journal_title：American journal of botany

authors： Sugai K,Setsuko S,Uchiyama K,Murakami N,Kato H,Yoshimaru H

更新日期：2012-02-01 00:00:00

abstract：:Nuclear DNA contents (4C) were estimated by Feulgen microdensitometry in 27 species of slipper orchids. These data and recent information concerning the molecular systematics of Cypripedioideae allow an interesting re-evaluation of karyotype and genome size variation among slipper orchids in a phylogenetic context. DN...

journal_title：American journal of botany

authors： Cox A,Abdelnour G,Bennett M,Leitch I

更新日期：1998-05-01 00:00:00

abstract：PREMISE:Gynomonoecy is an infrequent sexual system in angiosperms, although widely represented within the Asteraceae family. Currently, the hypothesis of two nuclear loci controling gynomonoecy is the most accepted. However, the genic interactions are still uncertain. Anacyclus clavatus, A. homogamos, and A. valentinus...

journal_title：American journal of botany

authors： Álvarez I,Agudo AB,Herrero A,Torices R

更新日期：2020-01-01 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：:Sex ratio and sexual dimorphism in physiology and growth were studied in the dioecious tree Ilex aquifolium at two localities in northern Spain. Genet sex ratio was significantly male biased in one locality but not in the other. However, ramet and flowering ramet sex ratios were male biased at both study sites. Males ...

journal_title：American journal of botany

authors： Obeso JR,Alvarez-Santullano M,Retuerto R

更新日期：1998-11-01 00:00:00

abstract：:Marchantia inflexa, a dioecious thallose liverwort, is sexually dimorphic in clonal expansion traits. We used selection analyses to measure the magnitude and direction of selection on clonal fitness to uncover possible mechanisms for the maintenance of preadult sexually dimorphic characters. We planted replicates of g...

journal_title：American journal of botany

authors： Fuselier L,McLetchie N

更新日期：2002-04-01 00:00:00

abstract：:Epiphytes are ecologically important components of tropical forests worldwide and yet they have been underrepresented in studies of reproductive biology. Given the presumed ephemeral nature of their substrates, and the importance of dispersal and colonization, epiphytes might be expected to undergo substantial inbreed...

journal_title：American journal of botany

authors： Hooper E,Haufler C

更新日期：1997-12-01 00:00:00

abstract：UNLABELLED:• PREMISE OF THE STUDY:The evolution of invasiveness has been extensively studied in natural ecosystems; however, far less is known about the evolution of agricultural invasiveness, despite the major economic impact of weeds on crop productivity. Examining the population structure of recently arisen weeds c...

journal_title：American journal of botany

authors： Waselkov KE,Olsen KM

更新日期：2014-10-01 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：:After 120 yr of burial in moist, well-aerated sand, 23 seeds of Verbascum blattaria and two seeds of a Verbascum sp. germinated and produced normal plants (50% germination for Verbascum). After a 6-wk cold treatment, a single seed of Malva rotundifolia germinated also, producing a normal plant (2% germination). Plants...

journal_title：American journal of botany

authors： Telewski FW,Zeevaart JA

更新日期：2002-08-01 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

authors： Wolf P

更新日期：1997-10-01 00:00:00

abstract：UNLABELLED:• PREMISE OF THE STUDY:Island plants are over-exploited and "under-explored." Understanding the reproductive biology of plants, especially rare species, is fundamental to clarifying their evolution, estimating potential for change, and for creating effective conservation plans. Clarification of sexual syste...

journal_title：American journal of botany

authors： Anderson GJ,Anderson MK,Patel N

更新日期：2015-03-01 00:00:00

abstract：:Wood, or secondary xylem, is composed mostly of three components-cellulose, hemicelluloses, and lignin. Yet this apparent simplicity is deceiving because the sophisticated arrangement of the components on various structural levels, ranging from intricate molecular architecture to defined cellular arrangements to tissu...

journal_title：American journal of botany

authors： Koehler L,Telewski FW

更新日期：2006-10-01 00:00:00

abstract：:In an age of rapid global change, it is imperative that we continue to improve our understanding of factors that govern genetic differentiation in plants to inform biologically reasonable predictions for the future and enlighten conservation and restoration practices. In this special issue, we have assembled a set of ...

journal_title：American journal of botany

authors： Etterson JR,Schneider HE,Gorden NL,Weber JJ

更新日期：2016-01-01 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：: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

authors： Walter R,Epperson BK

更新日期：2004-04-01 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:The Eocene-Oligocene transition (EOT; 34-33 Ma) was marked by global cooling and increased seasonality and aridity, leading to a shift in North American floras from subtropical forests to deciduous hardwood forests similar to today. This shift is well documented taxonomically and biogeographically, but its ecol...

journal_title：American journal of botany

authors： Butrim MJ,Royer DL

更新日期：2020-12-01 00:00:00

abstract：PREMISE OF THE STUDY:We developed simple sequence repeat (SSR) markers from expressed sequence tags (ESTs) for Callitris columellaris sensu lato (s.l.) to elucidate population genetic structure and detect outlier loci by genome scan. METHODS AND RESULTS:mRNA from an individual seedling was subjected to cDNA synthesis ...

journal_title：American journal of botany

authors： Sakaguchi S,Uchiyama K,Ueno S,Ujino-Ihara T,Tsumura Y,Prior LD,Bowman DM,Crisp MD,Isagi Y

更新日期：2011-12-01 00:00:00

abstract：:The fresh weights of suspension cultures of pear (Pyrus communis) and quince (Cydonia oblonga) increased exponentially for 30 to 40 days after subculturing. Transferring pear cultures to media in which quince cultures had grown for 10 days resulted in a 70% inhibition of callus growth. Transferring quince cultures to ...

journal_title：American journal of botany

authors： Moore R

更新日期：1986-01-01 00:00:00

abstract：PREMISE OF THE STUDY:It has been hypothesized that two flower types permit flexible allocation of resources to female and male functions, yet empirical evidence for the sex-allocation hypothesis remains scarce in gynomonoecious species. To characterize resource allocation to pistillate and perfect flowers and allocatio...

journal_title：American journal of botany

authors： Mamut J,Xiong YZ,Tan DY,Huang SQ

更新日期：2017-03-01 00:00:00

abstract：:In spite of the ecological and economic importance of temperate bamboos, relatively little is known about their population biology or evolutionary history. Recently, hybridization has emerged as a potential source of diversity in this group, as well as an underlying cause of taxonomic problems. As part of a broader ph...

journal_title：American journal of botany

authors： Triplett JK,Oltrogge KA,Clark LG

更新日期：2010-03-01 00:00:00

abstract：:The plastid trnL-F region has proved useful in molecular phylogenetic studies addressing diverse evolutionary questions from biogeographic history to character evolution in a broad range of plant groups. An important assumption for phylogenetic reconstruction is that data used in combined analyses contain the same phy...

journal_title：American journal of botany

authors： Pirie MD,Vargas MP,Botermans M,Bakker FT,Chatrou LW

更新日期：2007-06-01 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：:Partial cambial mortality is a growth form that is characteristic of Pinus aristata trees. To better elucidate their cambial death pattern, tree size and aspect of cambial death data were gathered from three Pinus aristata forests in central Colorado, USA. Stripping frequency tended to be higher for larger diameter cl...

journal_title：American journal of botany

authors： Schauer AJ,Schoettle AW,Boyce RL

更新日期：2001-04-01 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

authors： Davis CC,Anderson WR

更新日期：2010-12-01 00:00:00