Fundamental, ecological, and agricultural aspects of nitrogen metabolism in higher plants : proceedings of a symposium

Section 1: Uptake and translocation of nitrogen.- 1.1 Regulation of the absorption and release of nitrate by plant cells A review of current ideas and methodology.- 1.2 The influence of the form and concentration of inorganic nitrogen supplied on nitrogen uptake by Ankistrodesmus falcatus.- 1.3 Nitrate uptake and reduction in sugar-beet seedlings.- 1.4 Effects of root temperature on uptake of nitrate and ammonium ions by barley grown in flowing-solution culture.- 1.5 Nitrate-uptake characteristics of roots as affected by nitrate supply.- 1.6 A substrate cycling model for nitrate uptake by Pisum sativum seedlings: A key to sensitivity of response of net influx to substrate and effectors?.- 1.7 Nitrate and ammonium absorption by plants growing at a sufficient or insufficient level of phosphorus in nutrient solutions.- 1.8 Flow of N and activities of N-assimilating enzymes in roots of N-limited Pisum sativum.- 1.9 Patterns of N uptake, accumulation and assimilation in Lemna gibba when grown with exponentially increasing daily doses of N.- 1.10 Translocation and metabolism of nitrogen: whole plant aspects.- 1.11 Cycling of amino-nitrogen between shoots and roots in wheat seedlings.- 1.12 Nitrogen retranslocation in plants of maize, lupin and cocklebur.- 1.13 Alterations in enrichment of NO3? and reduced-N in xylem exudate during and after an extended plant exposure to 15NO3?.- 1.14 Amino acid loading by minor veins of Commelina benghalensis: An integration of structural and physiological aspects.- 1.15 Tobacco mutants of amino acid membrane transport: uptake of L-valine in leaf discs from the double mutant Valr-2 and its monogenic derivatives.- 1.16 Sink control of amino acid transport into developing seeds of Vicia faba and Pisum sativum.- 1.17 Amino acid efflux from seed coats and from cotyledons of developing and germinating pea seeds.- 1.18 Translocation of labelled nitrogen in oilseed rape.- Section 2: Biochemical aspects.- 2.1 Biochemical aspects of nitrogen metabolism in a whole plant context.- 2.2 An evaluation of the stoichiometry of in vivo nitrate assimilation in Zea mays.- 2.3 Influence of boron on nitrate reductase in roots of Zea mays.- 2.4 The influence of and dark conditions on the reduction of nitrate in leaves and roots of maize 165.- 2.5 Root contribution to nitrate reduction in barley seedlings (Hordeum vulgare L.).- 2.6 Nitrogen metabolism in plastids of pea roots.- 2.7 Isoforms of glutamine synthetase in chickpea.- 2.8 Partitioning of reduced-nitrogen derived from exogenous nitrate in maize roots: Initial priority for protein synthesis.- 2.9 A cysteine- stimulated in vitro inactivation of barley leaf nitrate reductase.- 2.10 15N nuclear magnetic resonance spectroscopy: a powerful tool to study amino acid biosynthesis in higher plants.- 2.11 Separation of amino acids by high performance liquid chromatography.- 2.12 Glutathione, a tripeptide which may function as a temporary storage compound of excessive reduced sulphur in H2S fumigated spinach plants.- 2.13 The effect of sulfide in the ambient air on amino acid metabolism of spinach leaves.- 2.14 Nitrogen uptake, assimilation and transport in barley in the presence of atmospheric nitrogen dioxide.- 2.15 Effect of quality on the alanine and aspartate aminotransferases in Wolffla arrhiza.- 2.16 Senescence and nitrogen metabolism in annual plants.- 2.17 Water relations of cowpea fruits during development.- 2.18 Turnover of peroxisomal proteins: Mechanistic aspects of catalase turnover in greening sunflower cotyledons.- 2.19 Influence of partial defoliation of green pepper on the senescence, growth, and nitrate reductase of the remaining leaf.- 2.20 Chloroplast lipid constituents from leaves of rape plants as affected by nitrogen.- Section 3: Interactions between C and N metabolism.- 3.1 Interactions between nitrogen and carbon metabolism in a whole plant context.- 3.2 Dependence of nitrate reduction on root soluble carbohydrates in wheat seedlings.- 3.3 Effect of nitrogen nutrition on photosynthetic apparatus of wheat during tillering.- 3.4 The distribution of inorganic nitrogen and nitrate assimilation in different regions of a Zea mays leaf.- 3.5 A photosynthetic and 15N investigation of the differential growth response of barley to nitrate, ammonium, and nitrate + ammonium nutrition.- 3.6 Nitrate or ammonium nutrition in french bean.- 3.7 Modification of 14C photodistribution into C4 acids of maize leaves by type of nitrogen supply.- 3.8 Refixation of photorespiratory ammonia and the role of alanine in photorespiration: studies with 15N.- 3.9 Effects of the glutamine synthetase inhibitor methionine sulfoximine on CO2 fixation in Lemna gibba.- 3.10 Distribution of leaf nitrogen concentration in relation to leaf exposure in peach tree canopies.- 3.11 A simulation model of growth and C and N metabolism in young maize plants.- Section 4: Ecological aspects.- 4.1 Nitrogen assimilation in an ecological context.- 4.2 Nitrate reduction in the leaves and numbers of nitrifiers in the rhizosphere of Plantago lanceolata, growing in two contrasting sites.- 4.3 Responses of Plantago species to various exponential addition rates of nitrate: A brief report.- 4.4 Growth, ionic balance, proton excretion, and nitrate reductase activity in Alnus and Hippophae supplied with different sources of nitrogen.- 4.5 Effect of nodulation on the nitrate assimilation in vegetative soybean plants.- Section 5: Agricultural aspects.- 5.1 Quantitative relationships for the dependence of growth rate of arable crops on their nitrogen content, dry weight and aerial environment.- 5.2 The course of nitrogen uptake by spring barley from soil and fertilizer nitrogen.- 5.3 Nitrogen assimilation in field-grown winter wheat: Direct measurements of nitrate reduction in roots using 15N.- 5.4 Nitrogen redistribution and its loss in wheat.- 5.5 Influence of the level of nitrogen application on the carbon and nitrogen distribution in selected wheat varieties.- 5.6 Interactions between nitrate uptake and N2 fixation in white clover.- 5.7 Accumulation and reduction of nitrate in cereal plants dependent on N supply.- 5.8 Supply of soil nitrogen to the plant during the growing season.- 5.9 Nitrogen supply from some soil types with various organic matter treatments.- 5.10 Dependence of soil mineral N on N-fertilizer application.- 5.11 A kinetic approach to determine mineralisable soil nitrogen.- 5.12 Distribution of nitrate, exchangeable and non-exchangeable ammonium in the soil-root interface.- 5.13 Fate of sheep urine-N applied to an unfertilised grass sward.- 5.14 Means of preventing nitrate accumulation in vegetables and pasture plants.- 5.15 Nitrate accumulation in spinach: Uptake and reduction of nitrate during a dark or a low light night period.- 5.16 The role of nitrate in osmoregulation of Italian ryegrass.- 5.17 Does nitrate play a role in osmoregulation?.- 5.18 Reduction of the nitrate concentration of lettuce grown in recirculating nutrient solution.- 5.19 The effect of nitrogen fertilization on nitrate accumulation and yield of some field vegetables.- The Nitrogen Ballade.- Acknowledgements.