Barrancaceae: A new green algal lineage with structural and behavioral adaptations to a fluctuating environment.

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：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：:This paper reports the frequency of spontaneous amphiploids or neopolyploids in experimental interspecific hybrids in two annual sections of Gilia (Polemoniaceae, sects. Arachnion and Gilia, x = 9). In each section the species were intercrossed in numerous hybrid combinations to obtain an array of F1 hybrid types; sev...

journal_title：American journal of botany

authors： Grant V

更新日期：2002-08-01 00:00:00

abstract：PREMISE OF THE STUDY:Drosera peltata var. nipponica, an element of the East Asia warm-temperate vegetation, and D. rotundifolia, a widely distributed boreal species, reach one of their northernmost and southernmost limits, respectively, on the Korean Peninsula. Because the Last Glacial Maximum (LGM)-Holocene dynamics o...

journal_title：American journal of botany

authors： Chung MY,López-Pujol J,Chung MG

更新日期：2013-11-01 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：UNLABELLED: PREMISE OF THE STUDY:Polyploid speciation has been important in plant evolution. However, the conditions that favor the origination and persistence of polyploids are still not well understood. Here, we examine origins of 16 polyploid species in Mentzelia section Trachyphytum. • METHODS:We used phylogeny r...

journal_title：American journal of botany

authors： Brokaw JM,Hufford L

更新日期：2010-09-01 00:00:00

abstract：PREMISE OF THE STUDY:Although our awareness of ploidy diversity has expanded with the application of flow cytometry, we still know little about the extent to which cytotypes within mixed-ploidy populations are genetically differentiated across environmental gradients. METHODS:To address this issue, we reared 14 popula...

journal_title：American journal of botany

authors： Etterson JR,Toczydlowski RH,Winkler KJ,Kirschbaum JA,McAulay TS

更新日期：2016-01-01 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：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：:Polyploids have significantly influenced angiosperm evolution. Understanding the genetic consequences of polyploidy is advanced by studies on synthetic allopolyploids that mimic natural species. In Nicotiana, Burk (1973) and Kostoff (1938) generated synthetic tobacco (N. tabacum) using the parents ♀N. sylvestris × ♂N....

journal_title：American journal of botany

authors： Lim KY,Souckova-Skalicka K,Sarasan V,Clarkson JJ,Chase MW,Kovarik A,Leitch AR

更新日期：2006-06-01 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：:Paddy fields are one of the dominant anthropogenic sources of methane emission to the atmosphere, and the main passageway of methane from paddy soil is through the rice plant. However, the effect of aquatic weeds on methane emission from rice paddies has not been properly evaluated yet. Methane emission from weeded po...

journal_title：American journal of botany

authors： Inubushi K,Sugii H,Nishino S,Nishino E

更新日期：2001-06-01 00:00:00

abstract：:The selective maintenance of gynodioecy depends on the relative fitness of the male-sterile (female) and hermaphroditic morphs. Females may compensate for their loss of male fitness by reallocating resources from male function (pollen production and pollinator attraction) to female function (seeds and fruits), thus in...

journal_title：American journal of botany

authors： Williams CF,Kuchenreuther MA,Drew A

更新日期：2000-05-01 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：PREMISE OF THE STUDY:A prevailing hypothesis in forest succession is that shade-tolerant species grow more slowly than shade-intolerant species, across light conditions, because they prioritize carbon (C) allocation to storage. We examined this hypothesis in a confamilial pair of species, including one of the fastest-g...

journal_title：American journal of botany

authors： Piper FI,Sepúlveda P,Bustos-Salazar A,Zúñiga-Feest A

更新日期：2017-05-01 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：:The timing, geographical locations, causes, and consequences of crop domestication have long been major concerns of archaeologists, and agricultural origins and dispersals are currently more relevant than ever to scientists seeking solutions to elusive problems involving food insecurity and global health disparities. ...

journal_title：American journal of botany

authors： Langlie BS,Mueller NG,Spengler RN,Fritz GJ

更新日期：2014-10-01 00:00:00

abstract：:Accurate estimates of inbreeding depression are necessary in order to predict the evolutionary dynamics of a population, but many studies estimate inbreeding depression based solely on components of female function such as fruit set, seed set, and seed quality. Because total fitness is achieved through both male and f...

journal_title：American journal of botany

authors： Hayes CN,Winsor JA,Stephenson AG

更新日期：2005-01-01 00:00:00

abstract：PREMISE OF THE STUDY:Hybridization and polyploidization (allopolyploidy) are ubiquitous in the evolution of plants, but tracing the origins and subsequent evolution of the constituent genomes of allopolyploids has been challenging. Genome doubling greatly complicates genetic analyses, and this has long hindered investi...

journal_title：American journal of botany

authors： Buggs RJ,Renny-Byfield S,Chester M,Jordon-Thaden IE,Viccini LF,Chamala S,Leitch AR,Schnable PS,Barbazuk WB,Soltis PS,Soltis DE

更新日期：2012-02-01 00:00:00

abstract：PREMISE OF THE STUDY:In animal-pollinated plants, autonomous selfing may provide reproductive assurance when pollinators or reproductive partners are limited. Under such circumstances, the contribution of pollinator-mediated seed set to total seed production also may be more variable compared with situations in which p...

journal_title：American journal of botany

authors： Brys R,de Crop E,Hoffmann M,Jacquemyn H

更新日期：2011-11-01 00:00:00

abstract：:Floral morphology of the 13 species of Moringa ranges from actinomorphic flowers with little hypanthium to highly zygomorphic flowers with well-developed hypanthia. Scanning electron and light microscopy were used to identify ontogenetic differences among two actinomorphic and eight zygomorphic species. All species sh...

journal_title：American journal of botany

authors： Olson ME

更新日期：2003-01-01 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

authors： Pabón-Mora N,Litt A

更新日期：2011-09-01 00:00:00

abstract：:Reproductive traits of tropical tree species vary predictably in relation to successional stage, but this variation may be due to the species' phylogenetic histories rather than selective pressures imposed by regeneration requirements. Reproductive phenology, tree size at the onset of reproduction, and fecundity of 11...

journal_title：American journal of botany

authors： Davies SJ,Ashton PS

更新日期：1999-12-01 00:00:00

abstract：:Pinus rzedowskii is an endangered pine species from Michoacán (central México), which has been previously reported from only three localities. Classified within the subgenus Strobus, it exhibits intermediate morphological characters between subgenera Strobus and Pinus. We analyzed genetic aspects that could shed light...

journal_title：American journal of botany

authors： Delgado P,Piñero D,Chaos A,Pérez-Nasser N,Alvarez-Buylla ER

更新日期：1999-05-01 00:00:00

abstract：PREMISE:Light is critical in the ability of plants to accumulate chlorophyll. When exposed to far-red (FR) light and then grown in white light in the absence of sucrose, wild-type seedlings fail to green in a response known as the FR block of greening (BOG). This response is controlled by phytochrome A through repressi...

journal_title：American journal of botany

authors： Alameldin HF,Oh S,Hernandez AP,Montgomery BL

更新日期：2020-02-01 00:00:00

abstract：:A conspicuous feature of Vochysiaceae flowers is their single fertile stamen. In some genera, the stamen is in front of a petal, whereas in others it is in front of a sepal. This difference has been attributed to two independent reductions, which implies the stamen is not homologous across the family. The observation ...

journal_title：American journal of botany

authors： Litt A,Stevenson DW

更新日期：2003-11-01 00:00:00

abstract：:The evolutionary origins of the morphological and taxonomic diversity of angiosperms is poorly known. We used the genus Melianthus to explore the diversification of the southern African flora. Melianthus comprises eight species, and a phylogeny based on one nuclear and two plastid genes, as well as a morphological dat...

journal_title：American journal of botany

authors： Linder HP,Dlamini T,Henning J,Verboom GA

更新日期：2006-07-01 00:00:00

abstract：:Gas exchange was measured in two subalpine herbs during alternating periods of sun and shade that simulated natural cloud patterns. Stomatal conductance (g) in the subalpine herb Helianthella quinquenervis was reduced by as much as 75% during 5-min shade periods that ranged in photosynthetic photon flux density (PPFD)...

journal_title：American journal of botany

authors： Knapp AK,Smith WK

更新日期：1990-02-01 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

authors： Gonzales E,Hamrick JL,Smouse PE

更新日期：2008-10-01 00:00:00

abstract：:Interspecific hybridization is considered a possible mechanism of plant diversification. The Andes are a hotspot of biodiversity, but hybridization in Andean taxa has so far not been investigated intensively. The current study investigates crossability in Caiophora (Loasaceae subfam. Loasoideae) by experimental inters...

journal_title：American journal of botany

authors： Ackermann M,Achatz M,Weigend M

更新日期：2008-09-01 00:00:00