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Antony N. Dodd is a plant scientist who is interested in chronobiology and circadian rhythms. He was inspired to study plant biology after attending lectures by Howard Griffiths, which showed how biochemical processes in plants could be studied over 24-hour cycles. Dodd pursued a career in research because he was fascinated by the control of daily cycles of Crassulacean acid metabolism in plants. He is motivated by the social element of science and the interactions with his research group and colleagues. Dodd provides advice for scientists, such as investing time to get things right, not only chasing big papers, and being collegial. He also discusses his favorite New Phytologist papers, which explore the use of chemical biology to study circadian rhythms in plants. Dodd mentions two favorite plant species, Agave americana and Aegagropila linnaei, and their significance in his research. [Extracted from the article]

This article is an interview with Peter J. Franks, a plant scientist who specializes in plant physiology and plant-climate interactions. Franks discusses his interest in plant science, which was sparked by his experiences in rainforests and his fascination with the diverse uses of plants by indigenous tribes. He also explains his decision to pursue a career in research, driven by his curiosity and the desire to contribute to scientific knowledge. Franks mentions his role models in the field and highlights some recent papers in the journal New Phytologist that have made significant advancements in understanding stomatal control and signaling in plants. He also shares his favorite plant species, including the extinct Cooksonia and the living fossil Austrobaileya scandens. Overall, Franks' research aims to integrate geological, molecular, and physiological information to understand the co-evolution of Earth's climate and vegetation. [Extracted from the article]

Summary: Anatomically preserved fossils allow estimation of hydraulic parameters, potentially providing constraints on interpreting whole‐plant physiology. However, different organ systems have typically been considered in isolation – a problem given common mismatches of high and low conductance components coupled in the hydraulic path of the same plant. A recent paper addressed the issue of how to handle resistance mismatches in fossil plant hydraulics, focusing on Carboniferous medullosan seed plants and arborescent lycopsids. Among other problems, however, a fundamental error was made: the transpiration stream consists of resistances in series (where resistances are additive and the component with the largest resistance can dominate the behavior of the system), but emphasis was instead placed on the lowest resistance, effectively treating the system as resistances in parallel (where the component with the smallest resistance will dominate the behavior). Instead of possessing high assimilation capacities to match high specific stem conductances, it is argued here that individual high conductance components in these Paleozoic plants are nonetheless associated with low whole‐plant productivity, just as can be commonly seen in living plants. Resolution of how to handle these issues may have broad implications for the Earth system including geobiological feedbacks to rock weathering, atmospheric composition, and climate. [ABSTRACT FROM AUTHOR]

Keywords: hydraulic conductivity; rhizosphere; root-soil contact; soil drying; stomata; transpiration EN hydraulic conductivity rhizosphere root-soil contact soil drying stomata transpiration 1541 1543 3 05/20/20 20200615 NES 200615 The recent paper by Rodriguez-Dominguez & Brodribb ([9]) shows that the loss in soil-root hydraulic conductance is the primary constraint on water flow during water stress (soil water potential below -1 MPa) and that this initiates stomata closure. This is an important result as it highlights the link between stomatal regulation and belowground soil-root interactions, particularly those taking place at the root-soil interface and in the adjacent soil, the I rhizosphere i . Remarkably, as the soil dried out, root and soil-root interface hydraulic conductances dropped significantly and became the primary constraint on water flow, more than xylem cavitation. Despite stomatal closure alleviating the loss of soil hydraulic conductance I K i SB soil sb , soil drying caused a large drop of hydraulic conductance at the root-soil interface I K SB i sb i . [Extracted from the article]

The article presents an interview with Colin Brownlee, a member of the journal's editorial board. He talks about his parents' and teachers' encouragement as the inspiration behind his interest in plant science. He discusses his education, his career achievements, his decision to pursue a career in research, his role model(s), the motivation that keeps him going, his favorite papers published in the journal, and the Venus flytrap and the cacti as his favorite plants.

• It is widely recognized that the red:far-red ratio (ζ) acts as a signal that triggers plant morphogenesis. New insights into photomorphogenesis have been gained through experiments in controlled environments. Extrapolation of such results to field conditions requires characterization of the ζ signal perceived by plant organs within canopies. This paper presents a modeling approach to characterize this signal. • A wheat ( Triticum aestivum) architectural model was coupled with a three-dimensional light model estimating the irradiances of virtual sensors. Architectural parameters and ζ values were measured on two contrasting spring wheat canopies under outdoor conditions. Light simulations were compared with measurements, and an analysis of sensitivity to measurement conditions was carried out. • The model results agreed well with measurements and previously published data. The sensitivity analysis showed that ζ strongly depends on canopy development as well as on sky conditions, sensor orientation, and sensor field of view. • This paper shows that modeling enables investigation of ζ distribution in a canopy over space and time. It also shows that the characterization of light quality strongly depends on measurement conditions, and that any discrepancies in results are likely attributable to different experimental set-ups. The usefulness of this modeling approach for crop photomorphogenesis studies is discussed. [ABSTRACT FROM AUTHOR]

The article presents a list of research papers by published in different volumes of the journal The New Phytologist. Some of the papers included in this list are "Variation in photosynthetic acid metabolism in vascular plants: CAM and related phenomena," by W. Cockburn, "Fructans and the metabolism of sucrose in vascular plants," by C. J. Pollock, "The degradation of chlorophyll--a biological enigma," by G. A. F. Hendry, J. D. Houghton and S. B. Brown, and "Plant ion channels: whole cell and single channel studies," by M. Tester.

The authors discuss how plants overcome abiotic stress through the help of their associations with symbionts and pathogens. They say the usual knowledge is that symbiotic associations are beneficial, while pathogen associations are harmful. The author reveals that reactive oxygen species (ROS) and reactive nitrogen species (RNS) are produced in both associations, meaning the plant and the microbe must be able to deal with ROS from both sides. They comment on a paper published within the issue about the beneficial aspect of plant-pathogen interactions.

• Functional–structural plant models that include detailed mechanistic representation of underlying physiological processes can be expensive to construct and the resulting models can also be extremely complicated. On the other hand, purely empirical models are not able to simulate plant adaptability and response to different conditions. In this paper, we present an intermediate approach to modelling plant function that can simulate plant response without requiring detailed knowledge of underlying physiology.• Plant function is modelled using a‘canonical’ modelling approach, which uses compartment models with flux functions of a standard mathematical form, while plant structure is modelled using L-systems.• Two modelling examples are used to demonstrate that canonical modelling can be used in conjunction with L-systems to create functional–structural plant models where function is represented either in an accurate and descriptive way, or in a more mechanistic and explanatory way.• We conclude that canonical modelling provides a useful, flexible and relatively simple approach to modelling plant function at an intermediate level of abstraction.New Phytologist(2005)doi: 10.1111/j.1469-8137.2005.01330.x© New Phytologist(2005) [ABSTRACT FROM AUTHOR]

During the initial phases of elongation of pea internodes, oat and rice coleoptiles, oat mesocotyls, soybean hypocotyls and dandelion peduncles, net transverse orientation of cellulose wall microfibrils (Mfs) was found in the outer epidermal wall. This paper demonstrates that in all these axes, with the exception of rice coleoptile, net longitudinal orientation of microfibrils occurs in the outer epidermal wall in portions of the axes that were still elongating at the time of sampling. The timing of the transition to net longitudinal orientation and whether the transition proceeded acropetally or basipetally varied with the type of axis under study. The variability of the relationship between extension and the transition from net transverse to net longitudinal orientation suggests that factors other than extension are important in determining the transition. Layers of longitudinal wall microfibrils may be added to the extending epidermal wall to bolster its tensile strength commensurate with its function during and after extension. Attention is drawn to the parallels between the concept of tissue tension in growing axes and the concept that the epidermis functions as a stressed skin in the support of mature plant parts in primary growth. [ABSTRACT FROM AUTHOR]

Polyamines (Pas) and the cell wall have important roles in plant morphogenesis. An interaction between cell wall components (pectic substances) and polyamines is known and inhibition of polyamine biosynthesis induces inhibition of some morphogenic processes. This is the case of rhizogenesis in tobacco (Nicotiana tabacum L.) thin layers. This paper investigates whether inhibition of polyamine biosynthesis induces modifications in the structure, shape and size of the primary cell walls in tobacco thin layers cultured on a rhizogenic medium, and whether polyamines (putrescine and spermidine) administered in combination with their corresponding inhibitors DL-α-difluoromethylornithine + DL-α-difluoromethylarginine (DFMO + DFMA), cyclohexylamine (CHA), methylglyoxal-bis(guanylhydrazone) (MGBG) restore cell wall characteristics. In treatments with polyamine inhibitors, cell hypertrophy occurred in the lowermost layer of the explant in contact with the medium. Many unusual features were observed in the walls of the hypertrophic cells: an amorphous structure, loosening of the fibrillar component; detachment between contiguous cells, lysis of wall components and an uneven thickness often giving a wavy appearance (in transverse walls). The inhibitors reduced cell wall thickness, and caused a weak positive PATAg reaction for polysaccharides. Polyamines restored cell wall thickness and, in general, the other wall features. Our results show that polyamines are necessary for maintaining cell wall characteristics by strengthening the links between cell-wall components. [ABSTRACT FROM AUTHOR]

Ventilated Solardomes (hemispherical glasshouses) have been used for 20 yr for studying the effects of gaseous pollutants on plants. This paper describes a computer-operated facility for studying the effects of CO2 × temperature regimes on plants. The eight chambers were set up for factorial design experiments - with two levels of CO2 (ambient and ambient+ 340 ppmv), two levels of temperature (ambient and 3 °C tracked continuously above ambient) and two replicates of each CO2 × temperature treatment. Monitoring of environmental conditions within the chambers over a 2 yr period has shown highly effective control of CO2 and temperature regimes. Even with high-quality and u.v.-B transmitting glass, the irradiance in the PAR region was reduced by 18% within the domes. Variation in temperature across the radii of the domes increased with higher photosynthetic photon flux density (PPFD). Vapour pressure deficits (VPDs) in the ambient temperature domes compared well with outside conditions but were higher in the elevated temperature domes. The watering regime within the domes affected intermittently the relationship between 'dome' and 'outside' VPDs. The Solardome facility has been used extensively for studies of the impacts of climate change within the UK Programme on Terrestrial Initiative on Global Environmental Research (TIGER). [ABSTRACT FROM AUTHOR]

Innate growth potential and innate patterns of allocation to different plant parts are both subject to physiological limitations. Yet the ways in which these attributes not only vary between species but also exhibit plasticity in response to environmental change are important determinants of ecological behaviour and contribute strands to Plant Strategy Theory. In this paper, we review the evidence for innate variation in growth potential and partitioning and consider the implications of this variation for the development of high-level ecological syntheses. [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]

This paper describes how plants can be studied as developing modular systems, with growth described as a population-type process defined by the rate of production of modular plant parts. A simple model of dynamics of meristems is developed and is followed by discussion of such features of growth as meristematic flux and the change from vegetative to a flowering state, the positional distribution of meristems and the probabilities of meristems undergoing transitions that result in architectural differences between plants. [ABSTRACT FROM AUTHOR]

Plant growth analysis, demographic analysis and yield component analysis are three procedures used to study relationships underlying plant growth and development. Previously, it has been shown that demographic analysis is qualitatively different from plant growth analysis. This paper demonstrates how plant growth analysis and yield component analysis can be merged into a composite procedure, sequential plant growth analysis. The composite approach treats some of the traditional indices of plant growth, including leaf area ratio, leaf area index, unit leaf rate, relative growth rate, crop growth rate and harvest index, as yield components. Regression analysis is used to assess quantitatively the contributions of individual yield components to variations in growth and yield. Fitted curves and trends in coefficients of determination are both used to follow the time course of relationships during development. A study of vegetative growth in bean plants is used to illustrate the composite procedure. [ABSTRACT FROM AUTHOR]

The inhibition of germination by leaf canopies was investigated in Bidens pilosa, a widespread tropical colonizing weed species. Seeds of this species were sown in the shade of four natural vegetation types: early colonizing stage of an old field succession, a later stage of the same sere, short grass, and long grass. There were four control treatments: full sunlight on open soil, banana-leaf shade, `neutral' shade under white paper, and darkness. Since the temperature regimes under the canopies differed, the effect of temperature on the germination of the seeds was investigated. The results show that the leaf canopies of the vegetation types investigated are markedly effective in inhibiting germination of this species in the field. Inhibition by unfavourable temperatures could have been only a contributory factor. It is suggested that seed sensitivity to leaf canopy shade may be of importance in effecting changes in species composition in early successional stages, and in excluding open-habitat species from closed vegetation generally. [ABSTRACT FROM AUTHOR]

This paper discusses a recent extension of demographic techniques into a field more conventionally dealt with by plant growth analysis. It concludes that the two approaches are complementary. [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]

The adaptations of plants to environment can take many morphological and physiological forms. The rate at which new plant material is accumulated is an integrated measure of plant response to environment and is a useful character when comparing either genetic differences between populations or effects of different environmental conditions on populations. Several approaches have been made to the study of quantitative plant growth. With frequent harvesting, regression analysis provides a powerful tool in describing the relationship of total weight with time. In this paper we have adopted procedures outlined by Draper and Smith (1966) and applied regression analysis to two sets of data from our programme on Atriplex. These demonstrate ways in which appropriate polynomial regression equations can be objectively applied to the total weight-time relationship. Implications of fitting an inappropriate regression equation and the problems of extrapolation are also discussed. [ABSTRACT FROM AUTHOR]

The combination of autoradiography and a filter paper 'sandwich' technique using wheat plants labelled with [SUP14]C has shown that roots of wheat exude two types of compounds, viz. (a) non-diffusible material released from the apices of both primary and lateral roots and (b) diffusible material released along the whole length of the roots. The high amount of non-diffusible material compared with diffusible material suggests that the former may be more significant than previously anticipated in relation to root functions and microorganisms in the rhizosphere. [ABSTRACT FROM AUTHOR]

The article presents a list of names of the persons acknowledged for their expertise, and thanked for the time given in refereeing papers for the December 1, 1996 issue of the journal The New Phytologist. Some of the names included in the list here are L.K. Abbot, S. Avery, G. Bateman, C. Bell, C. Blom, L. Boddy, P. Bonfante, A. Davelos, J. Digby, J. Dightonm E. Dumas, J. Dunlop, R.D. Finlay, M. Pearson, H. Pourter, R. G. West, P.J. Temple, M.A. Tester, K. Thompson, J. Townend, T. Walton and P. Van Dijk.

This article presents a list of persons who analyzed papers on plant physiology for the periodical "New Phytologist." Those mentioned include L.K. Abbott, W. Allaway, M. Allen, F. Amijee, W. Armstrong, T.W. Ashenden, A.E. Ashford, C.J. Atkinson, P. Barlow, J.M. Bates, R. Baxter, K.D. Bennett, A. Borland, C. Brownlee, J.W.G. Cairney, R. Currah, D. Cutler and M.S. Davies. The list also includes H. Deising, J. Dodd, J. Frankland, J. Houghton, J.R. Green, J. Graham, M.J. Kirkby, D. Lawlor and E. Keklowski.

The article presents information related to the symposium being organized by the journal The New Phytologist, that will be taking place at the University of Wales, Bangor,Wales, in the month of April, 1997. The topic of the symposium will be putting plant physiology on the map, genetic analysis of developmental and adaptive traits. There is an international panel of invited speakers. The organizers invite both offers of paper and applications to participate from those with active interest in the field. The second symposium will be held in Bangor and will examine another rapidly developing area, the genetic mapping of the physiological character.

This article presents information related to symposium on plant physiology published in November 1, 1996 issue of the "New Phytologist." The symposium "Putting plant physiology on the map: genetic analysis of developmental and adaptive traits," will be held in the University of Wales, Bangor, from April 2 to 3, 1997. There is an international panel of invited speakers, including E. Belhassen, K. Bachman, R. Flavell, D. Lydiate, H. Nguyen, S. Quarrie, O. Rognli and S. Tanksley. The organizers invite both offers of papers and applications to participate from those with active interests in the field.