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The article comments on the prominence of papers featured in the "New Phytologist" journal that consider various aspects of plant interactions with the environment. The author believes that the relative change in scope can be traced back over more than a century that the journal has been published. The coordinated efforts of scientists are needed to respond to the challenges posed by atmospheric and climactic change.

Summary: Global ecology – the study of the interactions among the Earth's ecosystems, land, atmosphere and oceans – depends crucially on global observations: this paper focuses on space‐based observations of global terrestrial ecosystems. Early global ecology relied on an extrapolation of detailed site‐level observations, using models of increasing complexity. Modern global ecology has been enabled largely by vegetation indices (greenness) from operational space‐based imagery but current capabilities greatly expand scientific possibilities. New observations from spacecraft in orbit allowed an estimation of gross carbon fluxes, photosynthesis, biomass burning, evapotranspiration and biomass, to create virtual eddy covariance sites in the sky. Planned missions will reveal the dimensions of the diversity of life itself. These observations will improve our understanding of the global productivity and carbon storage, land use, carbon cycle−climate feedback, diversity−productivity relationships and enable improved climate forecasts. Advances in remote sensing challenge ecologists to relate information organised by biome and species to new data arrayed by pixels and develop theory to address previously unobserved scales. [ABSTRACT FROM AUTHOR]

An interview with Marcel van der Heijden , the head of the Plant–Soil Interactions Group at the Swiss Federal Research Institute Agroscope in Zurich, Switzerland and a professor in Mycorrhizal Ecology at Utrecht University in the Netherlands, is presented. He mentions things that motivated him and other factors that have influenced his decision to pursue a career in research.

Summary: Although primarily valued for their suitability for oceanographic applications and soil moisture estimation, microwave remote sensing observations are also sensitive to plant water content (Mw). Since Mw depends on both plant water status and biomass, these observations have the potential to be useful for a range of plant drought response studies. In this paper, we introduce the principles behind microwave remote sensing observations to illustrate how they are sensitive to plant water content and discuss the relationship between landscape‐scale Mw and common stand‐scale metrics, including plant‐scale relative water content, live fuel moisture content and leaf water potential. Lastly, we discuss how various sensor types can be leveraged for specific applications depending on the spatio‐temporal resolution needed. [ABSTRACT FROM AUTHOR]

This paper describes the ecology of a coastal alluvial plain at Chichiriviche in northern Venezuela. The area supports a great diversity of plant communities, ranging from mangroves on the seaward edge of the plain to non-halophytic, fresh-water communities on the landward side. Small differences on topography result in a mosaic of saline and less-saline environments . Rainfall is strongly seasonal, causing superficial flooding of the alluvial plain in the rainy season and the creation of a hypersaline substratum during the dry season. As a consequence, much of the plain is devoid on vegetation. Towards the landward side of the plain there are numerous small 'vegetation islands', fringed by halophilic succulent herbs, and made up of deciduous and semi-deciduous shrubs and trees together with non-halophytic CAM plants such as cacti and bromeliads. In subsequent papers the results of ecophysiological studies of these diverse plant species are presented. [ABSTRACT FROM AUTHOR]

The long period covered by this paper probably saw the most drastic changes wrought by man on the plant cover of these islands in the whole of postglacial history. Much of our information about vegetation changes comes from those parts of the country where peats and mires are abundant, which leaves those areas which were the cradle of successive cultural groups largely unrepresented. Sources of environmental evidence are now emerging even from this unpromising background, an important element amongst which are man's own works. The evidence of changes wrought by man may come from non-botanical as well as botanical material. Pollen, charcoal, phytoliths, seeds, mosses, and other macroscopic plant remains may be extracted, but indirect evidence may also be obtained from land snails, insects, bones (including small vertebrates), as well as from preserved soils and land surfaces. In the various environments considered a trend from forest through clearance to pastoral or arable agriculture can usually be demonstrated. These changes may ultimately result in site deterioration on a large scale, the nature of which will depend upon the ecological conditions and the practices at work. In extreme cases peat may form or soil erosion take place. On base-poor soils, soil acidification may become so intense that the land is no longer usable for traditional agriculture and is allowed to degenerate to moorland or heath. In early historic times much degraded land came into use again for hill-grazing, a process which further depauperated both the flora and the soils. [ABSTRACT FROM AUTHOR]

This article is an Editorial highlighting: Moseler et al., 226: 967–977; Cannon & Petit, 226: 978–983; Kremer & Hipp, 226: 987–1011; Leroy et al., 226: 1012–1017, 1171–1182, 1183–1197; Nagamitsu et al., 226: 1018–1028; Bartholomé et al., 226: 1088–1103; Crowl et al., 226: 1158–1170; Hipp et al., 226: 1198–1212. [ABSTRACT FROM AUTHOR]

615I.615II.616III.618IV.622V.625VI.627VII.628628References628 Summary: Invasion science is a very active subdiscipline of ecology. However, some scientists contend that theoretical integration has been limited and that predictive power remains weak. This paper, focusing on plants, proposes a new multi‐pronged research strategy that builds on recent advances in invasion science. More intensive studies on particular model organisms and ecosystems are needed to improve our understanding of the full suite of interacting factors that influence invasions (‘model system research’). At the same time, comparative studies across many study systems are essential for unravelling the context‐dependencies of insights that emerge from particular studies (‘multi‐site studies’); and quantitative synthesis based on large datasets should be constrained to well‐defined theoretical domains (‘focused meta‐analysis’). We also suggest ways for better integration of information about species biology and ecosystem characteristics (‘invasion syndromes’). We expect that a resulting theory of invasions will need to be conceived as a somewhat heterogeneous conglomerate of elements of varying generality and predictive power: laws that apply to well‐specified domains, general concepts and theoretical frameworks that can guide thinking in research and management, and in‐depth knowledge about the drivers of particular invasions. [ABSTRACT FROM AUTHOR]

• Anthropogenic nitrogen (N) addition may substantially alter the terrestrial N cycle. However, a comprehensive understanding of how the ecosystem N cycle responds to external N input remains elusive. • Here, we evaluated the central tendencies of the responses of 15 variables associated with the ecosystem N cycle to N addition, using data extracted from 206 peer-reviewed papers. • Our results showed that the largest changes in the ecosystem N cycle caused by N addition were increases in soil inorganic N leaching (461%), soil NO3- concentration (429%), nitrification (154%), nitrous oxide emission (134%), and denitrification (84%). N addition also substantially increased soil NH4+ concentration (47%), and the N content in belowground (53%) and aboveground (44%) plant pools, leaves (24%), litter (24%) and dissolved organic N (21%). Total N content in the organic horizon (6.1%) and mineral soil (6.2%) slightly increased in response to N addition. However, N addition induced a decrease in microbial biomass N by 5.8%. • The increases in N effluxes caused by N addition were much greater than those in plant and soil pools except soil NO3-, suggesting a leaky terrestrial N system. [ABSTRACT FROM AUTHOR]

A response from the authors of the article "Temperature Responses of Developmental Processes Have Not Been Affected by Breeding in Different Ecological Areas for 17 Crop Species" in issue 2012 is presented.

• This paper presents an architectural model of wheat (Triticum aestivum), designed to explain effects of light conditions at the individual leaf level on tillering kinetics. Various model variables, including blade length and curvature, were parameterized for spring wheat, and compared with winter wheat and other Gramineae species.• The architectural model enables simulation of plant properties at the level of individual organs. Parameterization was based on data derived from an outdoor experiment with spring wheat cv. Minaret.• Final organ dimensions of tillers could be modelled using the concept of relative phytomer numbers. Various variables in spring wheat showed marked similarities to winter wheat and other species, suggesting possibilities for a general Gramineae architectural model.• Our descriptive model is suitable for our objective: investigating light effects on tiller behaviour. However, we plan to replace the descriptive modelling solutions by physiological, mechanistic solutions, starting with the localized production and partitioning of assimilates as affected by abiotic growth factors.New Phytologist(2005)doi: 10.1111/j.1469-8137.2005.01337.x© New Phytologist(2005) [ABSTRACT FROM AUTHOR]

Ecological transitions are at the core of different modes of speciation. These transitions face both genetic and demographic hurdles. This paper focuses on how these hurdles are overcome, allowing ecological speciation and speciation via hybridization and/or polyploidy. Niche shifting is a two-step process. First there is the establishment of ill-adapted populations where ecological opportunity allows. This is followed by the genetic refinement of populations, which allows them to be integrated into novel communities and habitats. These steps are more readily accomplished in unsaturated floras, where competition is less intense. Ecological transitions in saturated floras may be facilitated by disturbance. Invasive species serve as heuristic model systems for understanding the early stages of speciation where niche shifts are involved. [ABSTRACT FROM AUTHOR]

Keywords: ecological and evolutionary genetics; evolutionary biology; floral evolution; heterostyly; plant exploration; pollination; reproductive systems GLO:F0R/01nov19:nph16212-fig-0001.jpg PHOTO (COLOR): (a) Eichhornia crassipes; (b) Narcissus triandrus, image courtesy of Lawrence Harder; (c) Babiana ringens with malachite sunbird, image courtesy of Bruce Anderson. gl Ecological and evolutionary genetics, evolutionary biology, floral evolution, heterostyly, plant exploration, pollination, reproductive systems. [Extracted from the article]

Numerous authors have attempted to quantity the physical properties of leaves in relation to aspects of leaf ecology, including decomposition, sclerophylly, herbivory, and leaf function and longevity. This paper examines the relative merits of the punch-and-die, tearing and shearing tests for assessing leaf physical properties. We conducted a series of these three mechanical tests on leaves of Solanum laciniatum, and determined the effect of various test parameters on the measurement of fracture properties. For the punch-and-die test, the parameters considered were machine speed, clearance between the punch and the die, edge definition of the punch, and area of the punch. Aspects of the tearing test examined were notch length, and effects, and length-to width requirements of t est strips, and for shearing tests the effects of blade proximity, angle and sharpness were investigated. All the test parameters investigated were found significantly to affect the assessment of leaf-fracture properties. In addition, fracture properties were found to vary significantly within leaves. Some general principles for designing and implementing tests are outlined. This study suggests that while punching and shearing tests are useful means of quantifying leaf fracture properties, the value of the tearing test may be reduced as it is most constrained by the biological nature of the test material. [ABSTRACT FROM AUTHOR]

Dark septate root endophytes (DSE) are conidial or sterile fungi (Deuteromycotina, Fungi Imperfecti) likely to be ascomycetous and colonizing plant roots. They have been reported for nearly 600 plant species representing about 320 genera and 100 families. DSE fungi occur from the tropics to arctic and alpine habitats and comprise a heterogeneous group that functionally and ecologically overlaps with soil fungi, saprotrophic rhizoplane-inhabiting fungi, obligately and facultatively pathogenic fungi and mycorrhizal fungi. Numerous species of undescribed sterile and anamorphic taxa may also await discovery. Although DSE are abundant in washed root and soil samples from various habitats, and are easily isolated from surface-sterilized roots of ecto-, ectendo-, endo- and non-mycorrhizal host species, their ecological functions are little understood. Studies of DSE thus fat have yielded inconsistent results and only poorly illustrate the role of DSE in their natural habitats. These inconsistencies are largely due to the uncertain taxonomic affinities of the strains of DSE used. In addition, because different strains of a single anamorph taxon seem to vary greatly in function, no clear generalizations on their ecological role have been drawn. This paper reviews the current literature on DSE and the ecology and discusses the need for and direction of future research. [ABSTRACT FROM AUTHOR]

Ozone concentrations in many parts of Europe exceed the proposed UN-ECE Critical Levels for the protection of ecosystems but there is so little known about the effects on native, herbaceous species, that it is presently impossible to judge what effect, if any, these concentrations are having on this group of plants. This paper reports the results of an initial screening of 32 taxa that was used to select a small number of species for further work. All were exposed to 70 nI I-1 O2 given for 7 h d-1 for two weeks and the response measured in terms of mean relative growth rate (&Rbar;), the allometric root/shoot coefficient (K), arid changes in induced chlorophyll fluorescence (FR). Only six species showed visible symptoms but 14 showed a significant reduction &Rbar;. There was no relationship between the extent of visible symptoms and growth reduction, confirming that visible symptoms are often of little value in determining growth sensitivity to O3 stress. There were marked differences within genera and within species; a population of Plantago major collected in Athens showed no effects, while a Derbyshire population, with a 24% , reduction in R, was the most sensitive of taxa tested, including Bel-W3 tobacco which has been specifically bred for O3 sensitivity. There was a significant regression of &Rbar;% change on the &Rbar; of controls (&Rbar;% = 12.4- 10.4 × R, P = 0.0007, r = -0.56), implying that > 30%. of the variation in response between taxa was related to the inherent &Rbar;; faster growing taxa tending to show a greater reduction in &Rbar; on exposure to O3. It is tentatively suggested that this may be related to differences in stomatal conductance. [ABSTRACT FROM AUTHOR]

This paper is concerned with the value of the ecological information provided by response functions. Two questions are considered. The first deals with the spatial reproducibility of response functions depending on the tree population and the location of the meteorological station that yielded the climatic data. The second concerns the temporal stability of the response function. The climate ring- width relationships are calculated for six populations of Pinus silvestris (L.). Twelve meteorological stations are involved in this calculation, over the period 1890-1980, divided in five sequences of 50 years . Analogies and differences between response functions are investigated using multi-dimensional analysis (principal component analysis and cluster analysis). Spatial analysis reveals that the climate ring-width relationship mainly depends on the population habit. The temporal analysis shows that instability is linked with the evolution of the habitat, more especially with the expansion of the forest cover. [ABSTRACT FROM AUTHOR]

This paper highlights major developments in the field of heavy metal tolerance in plants over the last 15 years. Advances in experimental and theoretical aspects are considered. The value of both intra- and interspecific studies in assessing the ecological significance of adaptive strategies is stressed. [ABSTRACT FROM AUTHOR]

At any point in time, any discipline in science tends to be seized by a particular methodology or enthusiasm and other approaches get 'dumped'. So it is in ecology -- although, because of obstinate individualism, nothing is ever completely forgotten. We are currently in a reductionist, population-dominated era. Twenty-five years ago, our interests lay primarily in comparisons of species. In between, the holistic approach has had a good run with studies of ecosystems everywhere. This introductory paper reflects on this history and particularly, because of the occasion, examines the value of the process of comparison. [ABSTRACT FROM AUTHOR]

Solanum dulcamara L. grows in widely contrasting habitats, from waterlogged and shaded to relatively dry and fully exposed sites. Representative seed samples from a number of populations were collected. Germination was studied under a variety of experimental conditions in order to determine whether populations from different habitats were genetically differentiated. Under the conditions employed in these experiments it was concluded that populations probably did not differ genetically in their germination responses. [ABSTRACT FROM AUTHOR]

In some pollen analytical studies, the required information can be obtained without a complete analysis of the core. The paper describes with a practical example, strategies for economically extracting the required information, and indicate some properties of these strategies. [ABSTRACT FROM AUTHOR]

Summary: Genome size varies 2400‐fold across plants, influencing their evolution through changes in cell size and cell division rates which impact plants' environmental stress tolerance. Repetitive element expansion explains much genome size diversity, and the processes structuring repeat 'communities' are analogous to those structuring ecological communities. However, which environmental stressors influence repeat community dynamics has not yet been examined from an ecological perspective.We measured genome size and leveraged climatic data for 91% of genera within the ecologically diverse palm family (Arecaceae). We then generated genomic repeat profiles for 141 palm species, and analysed repeats using phylogenetically informed linear models to explore relationships between repeat dynamics and environmental factors.We show that palm genome size and repeat 'community' composition are best explained by aridity. Specifically, Ty3‐gypsy and TIR elements were more abundant in palm species from wetter environments, which generally had larger genomes, suggesting amplification. By contrast, Ty1‐copia and LINE elements were more abundant in drier environments.Our results suggest that water stress inhibits repeat expansion through selection on upper genome size limits. However, elements that may associate with stress‐response genes (e.g. Ty1‐copia) have amplified in arid‐adapted palm species. Overall, we provide novel evidence of climate influencing the assembly of repeat 'communities'. [ABSTRACT FROM AUTHOR]

Comments on the initial success in the retrospective interpretation of the hydrosystem of trees as shown in the paper "Suitability of Chestnut Earlywood Vessel Chronologies for Ecological Studies," by P. Fonti and I. Garcia Gonzales. Features of dendroecology and dendroclimatology that need to be examined; Utility of the hydrosystem; Factors which can contribute to reconstruction of the climate in Central Europe.

Summary: Plant architecture strongly influences ecological performance, yet its role in plant evolution has not been explored in depth. By testing both phylogenetic and environmental signals, it is possible to separate architectural traits into four categories: development constraints (phylogenetic signal only); convergences (environmental dependency only); key confluences to the environmental driver (both); unknown (neither).We analysed the evolutionary history of the genus Euphorbia, a model clade with both high architectural diversity and a wide environmental range. We conducted comparative analyses of 193 Euphorbia species world‐wide using 73 architectural traits, a dated phylogeny, and climate data.We identified 14 architectural types in Euphorbia based on trait combinations. We found 22 traits and three types representing convergences under climate groups, 21 traits and four types showing phylogenetic signal but no relation to climate, and 16 traits and five types with both climate and phylogenetic signals.Major drivers of architectural trait evolution likely include water stress in deserts (selected for succulence, continuous branching), frost disturbance in temperate systems (selected for simple, prostrate, short‐lived shoots) and light competition (selected for arborescence). Simple architectures allowed resilience to disturbance, and frequent transitions into new forms. Complex architectures with functional specialisation developed under stable climates but have low evolvability. See also the Commentary on this article by Chomicki, 231: 910–912. [ABSTRACT FROM AUTHOR]

A recent re-analysis of the data of Salisbury (1974) claims his data do not support the hypothesis that seeds of species from shaded habitats are heavier than those from unshaded habitats, partly because the original analysis was inappropriate and partly because of bias in the dataset. We show first that the re-analysis itself contains errors, and second that the charge of bias is based largely on a misunderstanding. We also show that analysis of a larger dataset, drawn from Salisbury (1942) and from Salisbury (1974), provides convincing support for the hypothesis and suggests that the relationship is independent of life history. [ABSTRACT FROM AUTHOR]

It is argued that detailed studies of the functioning of populations cannot by themselves lead to an understanding of British vegetation. Several complementary lines of investigation are required to explore the role of past and present interactions between habitat templet and plant characteristics. Strategy concepts provide a framework in which to assemble information from such diverse fields of ecological research, and recent results suggest that the present ecologies of populations, species, families and communities remain strongly conditioned by patterns of ecological specialization which predate the development of the post glacial flora. [ABSTRACT FROM AUTHOR]

A main aim of studies of the British flora in future must be ecological, with plant ecology developed as a multidisciplinary and experimental science which has as its primary purpose the understanding of vegetation. The response of species to environment is largely mediated through the response of vegetation. It is essential to have an accepted and widely understood classification of British vegetation. Destruction of the more natural types of vegetation, with accompanying loss of species, should be a matter of national concern as many communities are irreplaceable. Their loss represents irreversible damage to our cultural heritage and a deterioration of the quality of our environment. Ecological understanding of vegetation is necessary to ensure that conservation achieves its primary purpose. [ABSTRACT FROM AUTHOR]

It has been suggested that applications of nitrogen-containing fertilizers can stimulate the germination of dormant Avena fatua L. seed in the field and may be used to reduce numbers of seeds in the soil. However, it is not clear whether a subsequent cultivation imposing a light treatment on a proportion of the buried seeds is also necessary. To study this question potassium nitrate (KNO3) was applied to dormant seed of A. fatua in darkness and in light under controlled laboratory conditions. Potassium nitrate had very little effect on germination in darkness but concentrations of 2 × 10-4, 2 × 10-3 and 2 × 10-2 M stimulated germination in the light. The degree of stimulation by light was related to the proportion of phytochrome that was maintained as Pfr, the physiologically active form, In the presence of 2 × 10-1 M KNO3 no germination occurred either in light or in darkness. [ABSTRACT FROM AUTHOR]

Data are presented from pollen analytical investigations of an upland basin peat site (GWC) at c. 395 m.o.d. on Cefn Gwernffrwd, mid-Wales, 15 km north of Llandovery and 15 km south-east of Tregaron Bog. The data are presented in an outline radiocarbon-dated pollen diagram, covering more than 9500 radiocarbon years and zoned in the conventional manner, and in a detailed pollen diagram covering Atlantic and Sub-Boreal times, divided into eight phases. The evidence indicates that pine (Pinus) was not a major post-glacial forest component in this locality, but that hazel (Corylus) may have dominated the upland plateau woods for much of the Boreal. The composition of the Mesolithic forest is discussed and compared with neighbouring areas of the British Isles in the light of this apparent abundance of Corylus and with regard to its migration route into mid-Wales in the Flandrian.. The date for the elm (Ulmus) decline horizon at site GWC is within the expected range and consistent with that obtained from Tregaron Bog. The site is 0.5 km from a recently discovered prehistoric complex of presumed Bronze Age date. Although there is firm evidence for Neolithic clearances, the impact on the forest in this locality was more severe in the Bronze Age. This is apparently at variance with sites elsewhere in mid-Wales, where an open upland landscape has been claimed since the early Neolithic, and more closely parallels findings in Northern Ireland. [ABSTRACT FROM AUTHOR]

Summary: The genus Quercus is among the most widespread and species‐rich tree genera in the northern hemisphere. The extraordinary species diversity in America and Asia together with the continuous continental distribution of a limited number of European species raise questions about how macro‐ and microevolutionary processes made the genus Quercus an evolutionary success. Synthesizing conclusions reached during the past three decades by complementary approaches in phylogenetics, phylogeography, genomics, ecology, paleobotany, population biology and quantitative genetics, this review aims to illuminate evolutionary processes leading to the radiation and expansion of oaks. From opposing scales of time and geography, we converge on four overarching explanations of evolutionary success in oaks: accumulation of large reservoirs of diversity within populations and species; ability for rapid migration contributing to ecological priority effects on lineage diversification; high rates of evolutionary divergence within clades combined with convergent solutions to ecological problems across clades; and propensity for hybridization, contributing to adaptive introgression and facilitating migration. Finally, we explore potential future research avenues, emphasizing the integration of microevolutionary and macroevolutionary perspectives. See also the Editorial on this article by Plomion & Martin, 226: 943–946. [ABSTRACT FROM AUTHOR]

Summary: Soil water and nutrient availability are key drivers of tree species distribution and forest ecosystem functioning, with strong species differences in water and nutrient use. Despite growing evidence for intraspecific trait differences, it remains unclear under which circumstances the effects of environmental gradients trump those of ontogeny and taxonomy on important functional dimensions related to resource use, particularly in tropical forests.Here, we explore how physiological, chemical, and morphological traits related to resource use vary between life stages in four species within the genus Micropholis that is widespread in lowland Amazonia. Specifically, we evaluate how environment, developmental stage, and taxonomy contribute to single‐trait variation and multidimensional functional strategies.We find that environment, developmental stage, and taxonomy differentially contribute to functional dimensions. Habitats and seasons shape physiological and chemical traits related to water and nutrient use, whereas developmental stage and taxonomic identity impact morphological traits –especially those related to the leaf economics spectrum.Our findings suggest that combining environment, ontogeny, and taxonomy allows for a better understanding of important functional dimensions in tropical trees and highlights the need for integrating tree physiological and chemical traits with classically used morphological traits to improve predictions of tropical forests' responses to environmental change. [ABSTRACT FROM AUTHOR]

Summary: Variation in resource availability can lead to phenotypic plasticity in the traits comprising the world‐wide leaf economics spectrum (LES), potentially impairing plant function and complicating the use of tabulated values for LES traits in ecological studies.We compared 14 Carex (Cyperaceae) species in a factorial experiment (unshaded/shaded × sufficient/insufficient P) to analyze how changes in the network of allometric scaling relationships among LES traits influenced growth under favorable and resource‐limited conditions.Changes in leaf mass per area (LMA) shifted the scaling relationships among LES traits expressed per unit area vs mass in ways that helped to sustain growth under resource limitation. Increases in area‐normalized photosynthetic capacity and foliar nitrogen (N) were correlated with increased growth, offsetting losses associated with mass‐normalized dark respiration and foliar N. These shifts increased the contributions to growth associated with photosynthetic N‐use efficiency and the N : P ratio.Plasticity in LMA is at the hub of the functional role of the LES as an integrated and resilient complex system that balances the relationships among area‐ and mass‐based aspects of gas exchange and foliar nutrient traits to sustain at least some degree of plant growth under differing availabilities of above‐ and below‐ground resources. [ABSTRACT FROM AUTHOR]

As a young professor at the University of Toronto, his laboratory characterized the ecology and evolution of plant mating and sexual systems in many plant species in the woodlands and wetlands of Canada (Thomson & Barrett, [73]; Barrett & Thomson, [15]; Eckert & Barrett, [34]; Larson & Barrett, [52]). Similarly, his research on the evolution of combined versus separate sexes (Barrett, [7],[8]; Dorken & Barrett, [33]; Case I et al i ., [16]; Yakimowski & Barrett, [83]), and the evolution of sex ratios (Stehlik & Barrett, [71]; Pickup & Barrett, [61]) incorporate ecological, theoretical and genetic dimensions to the problem at hand, in addition to consideration of both micro- and macroevolutionary scales. While a major focus of his career has been on microevolutionary changes within species to conduct powerful tests of evolutionary transitions, Spencer has been equally comfortable with macroevolutionary perspectives on these problems (Graham I et al i ., [39]; Friedman & Barrett, [37]), recognizing early on the power of the comparative method for studies on plant reproduction (Barrett I et al i ., [14]). ([82], in this issue pp. 1142-1150) suggest that cryptic pollen colouration may enhance plant reproductive success by protecting pollen from pollen thieves- insects that consume pollen but do not contribute to pollination. [Extracted from the article]

This article presents an introduction of the special issue of the journal "New Phytologist." This Special issue of the journal explore the impacts of variation in leaf structure on processes occurring from the level of the leaf itself to that ecosystem and biomes. The introductory review by Vince Gutschick assesses the basic consequences of differences in leaf structure, and this is followed by both reviews and research papers that expand on this theme: providing up-to-date accounts of the environmental, genotypic and whole-plant controls over leaf structure.

An interview with botanist Jana C. Vamosi is presented. Topics discussed include her interest in plant science, her decision to pursue a career in plant research, and her motivation to go to work on a daily basis. Also mentioned is her growing interest on historical ecology and the people who worked tirelessly in foundational research that involves collating historical records of plant biodiversity in herbaria.

Summary: Explaining variation in life history strategies is an enduring goal of evolutionary biology and ecology. Early theory predicted that for plants, annual and perennial life histories reflect adaptations to environments that experience alternative drought regimens. Nevertheless, empirical support for this hypothesis from comparative analyses remains lacking.Here, we test classic life history theory in Heliophila L. (Brassicaceae), a diverse genus of flowering plants native to Africa, controlling for phylogeny and integrating 34 yr of satellite‐based drought detection with 2192 herbaria occurrence records.We find that the common ancestor of these species was likely to be an annual, and that perenniality and annuality have repeatedly evolved, an estimated seven and five times, respectively. By comparing historical drought regimens, we show that annuals rather than perennial species occur in environments where droughts are significantly more frequent. We also find evidence that annual plants adapt to predictable drought regimens by escaping drought‐prone seasons as seeds.These results yield compelling support for longstanding theoretical predictions by revealing the importance of drought frequency and predictability to explain plant life history. More broadly, this work highlights scalable approaches, integrating herbaria records and remote sensing to address outstanding questions in evolutionary ecology. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the authors discuss various reports within the issue on topics including the diversity of nonmycorrhizal and mycorrhizal plants, the function of for nitrogen (N) and phosphorus (P) nutrition, and the biodiversity of arbuscular mycorrhiza (AM) fungi.

ContentsI.II.III.IV.V.AcknowledgementsReferences Summary: Flowering plants can be far more productive than other living land plants. Evidence is reviewed that productivity would have been uniformly lower and less CO2‐responsive before angiosperm evolution, particularly during the early evolution of vascular plants and forests in the Devonian and Carboniferous. This introduces important challenges because paleoecological interpretations have been rooted in understanding of modern angiosperm‐dominated ecosystems. One key example is tree evolution: although often thought to reflect competition for light, light limitation is unlikely for plants with such low photosynthetic potential. Instead, during this early evolution, the capacities of trees for enhanced propagule dispersal, greater leaf area, and deep‐rooting access to nutrients and the water table are all deemed more fundamental potential drivers than light. See also the Commentary on this article by Friedman, 215: 505–507. [ABSTRACT FROM AUTHOR]

The distribution patterns of tropical ectomycorrhizal ( ECM) fungi along altitudinal gradients remain largely unknown. Furthermore, despite being an iconic site for biodiversity research, virtually nothing is known about the diversity and spatial patterns of fungi on Mt Kinabalu and neighbouring mountain ranges., We carried out deep DNA sequencing of soil samples collected between 425 and 4000 m above sea level to compare richness and community composition of ECM fungi among altitudinal forest types in Borneo. In addition, we tested whether the observed patterns are driven by habitat or by geometric effect of overlapping ranges of species (mid-domain effect)., Community composition of ECM fungi was strongly correlated with elevation. In most genera, richness peaked in the mid-elevation montane forest zone, with the exception of tomentelloid fungi, which showed monotonal decrease in richness with increasing altitude. Richness in lower-mid- and mid-elevations was significantly greater than predicted under the mid-domain effect model., We provide the first insight into the composition of ECM fungal communities and their strong altitudinal turnover in Borneo. The high richness and restricted distribution of many ECM fungi in the montane forests suggest that mid-elevation peak richness is primarily driven by environmental characteristics of this habitat and not by the mid-domain effect. [ABSTRACT FROM AUTHOR]

Contents1582I.1582II.1583III.1588IV.1590V.15921592References1592 Summary: The importance of selenium (Se) for medicine, industry and the environment is increasingly apparent. Se is essential for many species, including humans, but toxic at elevated concentrations. Plant Se accumulation and volatilization may be applied in crop biofortification and phytoremediation. Topics covered here include beneficial and toxic effects of Se on plants, mechanisms of Se accumulation and tolerance in plants and algae, Se hyperaccumulation, and ecological and evolutionary aspects of these processes. Plant species differ in the concentration and forms of Se accumulated, Se partitioning at the whole‐plant and tissue levels, and the capacity to distinguish Se from sulfur. Mechanisms of Se hyperaccumulation and its adaptive significance appear to involve constitutive up‐regulation of sulfate/selenate uptake and assimilation, associated with elevated concentrations of defense‐related hormones. Hyperaccumulation has evolved independently in at least three plant families, probably as an elemental defense mechanism and perhaps mediating elemental allelopathy. Elevated plant Se protects plants from generalist herbivores and pathogens, but also gives rise to the evolution of Se‐resistant specialists. Plant Se accumulation affects ecological interactions with herbivores, pollinators, neighboring plants, and microbes. Hyperaccumulation tends to negatively affect Se‐sensitive ecological partners while facilitating Se‐resistant partners, potentially affecting species composition and Se cycling in seleniferous ecosystems. [ABSTRACT FROM AUTHOR]

The response of marine microalgal lipids to phosphorus is of central importance in phytoplankton ecology but remains poorly understood. We determined how taxonomically diverse microalgal species remodelled their lipid class profile in response to phosphorus availability and whether these changes coincided with those already known to occur in land plants and in the limited number of phytoplankton species for which data are available., The complete lipid class profile and specific lipid ratios influenced by phosphorus availability were quantified in two green microalgae and seven Chromalveolates exposed to phosphorus repletion, deprivation and replenishment., Lipid class cell quota changes in the two green microalgae resembled the currently described pattern of betaine lipids substituting for phospholipids under phosphorus depletion, whereas only two of the studied Chromalveolates showed this pattern. Sulpholipids counterbalanced phosphatidylglycerol only in Picochlorum atomus. In all other species, both lipids decreased simultaneously under phosphorus deprivation, although sulpholipids declined more slowly. Phosphorus deprivation always induced a decrease in digalactosyl-diacylglycerol. However, the ratio of digalactosyl-diacylglycerol to total phospholipids increased in eight species and remained unchanged in Isochrysis galbana., Marine phytoplankton seems to have evolved a diversified mechanism for remodelling its lipid class profile under the influence of phosphorus, with cryptophytes and particularly haptophytes exhibiting previously unobserved lipid responses to phosphorus. [ABSTRACT FROM AUTHOR]

Biomass allocation can exert a great influence on plant resource acquisition and nutrient use. However, the role of biomass allocation strategies in shaping plant community composition under nutrient limitations remains poorly addressed., We hypothesized that species-specific allocation strategies can affect plant adaptation to nutrient limitations, resulting in species turnover and changes in community-level biomass allocations across nutrient gradients. In this study, we measured species abundance and the concentrations of nitrogen and phosphorus in leaves and soil nutrients in an arid-hot grassland. We quantified species-specific allocation parameters for stems vs leaves based on allometric scaling relationships. Species-specific stem vs leaf allocation parameters were weighted with species abundances to calculate the community-weighted means driven by species turnover., We found that the community-weighted means of biomass allocation parameters were significantly related to the soil nutrient gradient as well as to leaf stoichiometry, indicating that species-specific allocation strategies can affect plant adaptation to nutrient limitations in the studied grassland. Species that allocate less to stems than leaves tend to dominate nutrient-limited environments., The results support the hypothesis that species-specific allocations affect plant adaptation to nutrient limitations. The allocation trade-off between stems and leaves has the potential to greatly affect plant distribution across nutrient gradients. [ABSTRACT FROM AUTHOR]

Understanding the role of individual organisms in whole-ecosystem carbon (C) fluxes is probably the biggest current challenge in C cycle research. Thus, it is unknown whether different plant community members share the same or different residence times in metabolic (τmetab) and nonmetabolic (i.e. structural) (τnonmetab) C pools of aboveground biomass and the fraction of fixed C allocated to aboveground nonmetabolic biomass ( Anonmetab)., We assessed τmetab, τnonmetab and Anonmetab of co-dominant species from different functional groups (two bunchgrasses, a stoloniferous legume and a rosette dicot) in a temperate grassland community. Continuous, 14-16-d-long 13C-labeling experiments were performed in September 2006, May 2007 and September 2007., A two-pool compartmental system, with a well-mixed metabolic and a nonmixed nonmetabolic pool, was the simplest biologically meaningful model that fitted the 13C tracer kinetics in the whole-shoot biomass of all species. In all experimental periods, the species had similar τmetab (5-8 d), whereas τnonmetab ranged from 20 to 58 d (except for one outlier) and Anonmetab from 7 to 45%., Variations in τnonmetab and Anonmetab were not systematically associated with species or experimental periods, but exhibited relationships with leaf life span, particularly in the grasses. Similar pool kinetics of species suggested similar kinetics at the community level. [ABSTRACT FROM AUTHOR]

Proline (Pro) is a versatile metabolite playing a role in the protection of plants against environmental stresses. To gain a deeper understanding of the regulation of Pro metabolism under predicted future climate conditions, including drought stress, elevated temperature and CO2, we combined measurements in contrasting grassland species (two grasses and two legumes) at multiple organisational levels, that is, metabolite concentrations, enzyme activities and gene expression., Drought stress (D) activates Pro biosynthesis and represses its catabolism, and elevated temperature ( DT) further elevated its content. Elevated CO2 attenuated the DT effect on Pro accumulation., Computational pathway control analysis allowed a mechanistic understanding of the regulatory changes in Pro metabolism. This analysis indicates that the experimentally observed coregulation of multiple enzymes is more effective in modulating Pro concentrations than regulation of a single step. Pyrroline-5-carboxylate synthetase (P5 CS) and pyrroline-5-carboxylate reductase (P5 CR) play a central role in grasses ( Lolium perenne, Poa pratensis), and arginase ( ARG), ornithine aminotransferase ( OAT) and P5 CR play a central role in legumes ( Medicago lupulina, Lotus corniculatus)., Different strategies in the regulation of Pro concentrations under stress conditions were observed. In grasses the glutamate pathway is activated predominantly, and in the legumes the ornithine pathway, possibly related to differences in N-nutritional status. [ABSTRACT FROM AUTHOR]