Ion Transport In Plants

This open access book presents the findings from on-site research into radioactive cesium contamination in various agricultural systems affected by the Fukushima Daiichi Nuclear Power Plant accident in March 2011. This third volume in the series reports on studies undertaken at contaminated sites such as farmland, forests, and marine and freshwater environments, with a particular focus on livestock, wild plants and mushrooms, crops, and marine products in those environments. It also provides additional data collected in the subsequent years to show how the radioactivity levels in agricultural products and their growing environments have changed with time and the route by which radioactive materials entered agricultural products as well as their movement between different components (e.g., soil, water, and trees) within an environmental system (e.g., forests). The book covers various topics, including radioactivity testing of food products; decontamination trials for rice and livestock production; the state of contamination in, trees, mushrooms, and timber; the dynamics of radioactivity distribution in paddy fields and upland forests; damage incurred by the forestry and fishery industries; and the change in consumers’ attitudes. Chapter 19 introduces a real-time radioisotope imaging system, a pioneering technique to visualize the movement of cesium in soil and in plants. This is the only book to provide systematic data on the actual change of radioactivity, and as such is of great value to all researchers who wish to understand the effect of radioactive fallout on agriculture. In addition, it helps the general public to better understand the issues of radio-contamination in the environment. The project is ongoing; the research groups from the Graduate School of Agricultural and Life Sciences of The University of Tokyo continue their work in the field to further evaluate the long-term effects of the Fukushima accident.

Ion Transport in Plants covers knowledge about ion transport in plants. The book discusses ultrastructural localization; formalism and membrane models; and membrane resistance and H+ fluxes. The text also describes ?+ fluxes in cells and organelles; Na+-?+ transport and ionic relations of the halophytes; and Cl- transport in vesicles. The ion transport in roots and the symplasm is also considered. Botanists, biochemists and biologists will find the book invaluable.

Life presumably arose in the primeval oceans with similar or even greater salinity than the present ocean, so the ancient cells were designed to withstand salinity. However, the immediate ancestors of land plants most likely lived in fresh, or slightly brackish, water. The fresh/brackish water origins might explain why many land plants, including some cereals, can withstand moderate salinity, but only 1 – 2 % of all the higher plant species were able to re-discover their saline origins again and survive at increased salinities close to that of seawater. From a practical side, salinity is among the major threats to agriculture, having been one of the reasons for the demise of the ancient Mesopotamian Sumer civilisation and in the present time causing huge annual economic losses of over 10 billion USD. The effects of salinity on plants include osmotic stress, disruption of membrane ion transport, direct toxicity of high cytoplasmic concentrations of sodium and chloride on cellular processes and induced oxidative stress. Ion transport is the crucial starting point that determines salinity tolerance in plants. Transport via membranes is mediated mostly by the ion channels and transporters, which ensure selective passage of specific ions. The molecular and structural diversity of these ion channels and transporters is amazing. Obtaining the detailed descriptions of distinct ion channels and transporters present in halophytes, marine algae and salt-tolerant fungi and then progressing to the cellular and the whole organism mechanisms, is one of the logical ways to understand high salinity tolerance. Transfer of the genes from halophytes to agricultural crops is a means to increase salt tolerance of the crops. The theoretical scientific approaches involve protein chemistry, structure-function relations of membrane proteins, synthetic biology, systems biology and physiology of stress and ion homeostasis. At the time of compiling this e-book many aspects of ion transport under salinity stress are not yet well understood. The e-book has attracted researchers in ion transport and salinity tolerance. We have combined our efforts to achieve a wider, more detailed understanding of salt tolerance in plants mediated by ion transport, to understand present and future ways to modify and manipulate ion transport and salinity tolerance and also to find natural limits for the modifications.

Cation Transporters in Plants presents expert information on the major cation transporters, along with developments of various new strategies to cope with the adverse effects of abiotic and biotic stresses. The book will serve as a very important repository for the scientist, researcher, academician and industrialist to enhance their knowledge about cation transport in plants. Further, applications listed in the book will facilitate future developments in crop designing strategies. This comprehensive resource provides an alternative strategy for abiotic and biotic stress management in agricultural and horticultural crops. In addition, it will further improve basic knowledge om the origin and mechanism of cation homeostasis and their role in developmental transition and stress regulation. Contains in-depth knowledge about various cation transporters in plants Provides information about important macro and micronutrient cation transporters and their applications in the agricultural and biotechnology sectors Facilitates agricultural scientists and industries in future crop designing strategies Provides an alternative strategy for abiotic and biotic stress management in agricultural and horticultural crops

In the first part (Part A) of this volume on transport, there was an emphasis on the processes occurring at the membranes bounding the cells. It was convenient to distinguish active and passive processes of transport across the membranes, and to recognize that certain transport processes may be regulated by internal factors in the cells such as cytoplasmic pH, concentrations of ions, of malate or of sugar in the vacuoles, or the hydrostatic pressure. Cells in tissues and organs show the same kinds of properties as individual cells, but in addition there can be cell to cell transport related to the organization of the tissue. Firstly cells within a tissue are separated from the external solutions by a diffusion path comprising parts of the cell walls and intercellular spaces; more generally this extra-cytoplasmic part of the tissue has been called the apoplasm. A similar term is "free space". Secondly, the anatomy of cells in tissues seems to allow some facilitated, local transport between cells in a symplasm. Entry into the symplast and subsequent transport in a symplasmic continuum seems to be privileged, in that ions may not have to mix with the bulk of the cytoplasm and can pass from cell to cell in particular cytoplasmic structures, plasmodesmata. In Chara plants, this kind of transport is found operating across the multi-cellular nodes as the main means of transport between the long internodal cells.

The study of solute transport in plants dates back to the beginnings of experimental plant physiology, but has its origins in the much earlier interests of humankind in agriculture. Given this lineage, it is not surprising that there have been many books on the transport of solutes in plants; texts on the closely related subject of mineral nutrition also commonly address the topic of ion transport. Why another book? Well, physiologists continue to make new discoveries. Particularly pertinent is the characterisation of enzymes that are able to transport protons across membranes during the hydrolysis of energy-rich bonds. These enzymes, which include the H + -A TPases, are now known to be crucial for solute transport in plants and we have given them due emphasis. From an academic point of view, the transport systems in plants are now appreciated as worthy of study in their own right-not just as an extension of those systems already much more widely investigated in animals. From a wider perspective, understanding solute transport in plants is fundamental to understanding plants and the extent to which they can be manipulated for agricultural purposes. As physiologists interested in the mechanisms of transport, we first set out in this book to examine the solutes in plants and where are they located. Our next consideration was to provide the tools by which solute movement can be understood: a vital part of this was to describe membranes and those enzymes catalysing transport.

Transport and Transfer Processes in Plants presents the proceedings of a symposium held in Canberra, Australia, in December 1975 under the auspices of the U.S.-Australia Agreement for Scientific and Technical Cooperation. It explores how organic materials and nutrients are distributed in plants and how plants are influenced by the interactions between various forms of both long- and short-distance transport. The book also considers how environmental factors regulate plant growth, how nutrients may be used in a more efficient manner, and how plants acquire disease. Divided into three parts encompassing 39 chapters, this book begins with an overview of the mechanisms underlying transport and distribution in plants; the effect of phloem capacity on plant growth and development; and short-distance transfer. It then introduces the reader to plasmodesmata and symplastic transport; how flow affects solute transport in plants; cytoplasmic streaming in characean algae; occurrence and function of transfer cells; movement of solutes from host to parasite in nematode infected roots; and nutrient uptake by roots and transport to the xylem. The book also discusses symplasmic transport and ion release to the xylem; regulation of nutrient uptake by cells and roots; transfer of ions and products of photosynthesis to guard cells; and vascular patterns in higher plants. It considers histochemical approaches to water-soluble compounds and their use in addressing problems of translocation; long-distance movement of tobacco mosaic virus in Nicotiana glutinosa; the influence of stomatal behavior on long-distance transport; and water transport through plants. This book will be a valuable resource for scientists, students, and researchers.

Ion transport - introduction and general principles; Cell membranes; Mitochondria; Chloroplasts; Algal cells; Storage tissues; Excised roots; Long-distance transport in roots; Whole plants; Halophytes; Salt glands; Stomata.