Advances in Nitrogen Fixation Research

As for the preceding four International Symposia on Nitrogen Fixation, held in Pullman, Washington USA (1974); Salamanca, Spain (1976); Madison, Wisconsin, USA (1978); and Canberra, Australia (1980), the 5th Symposium held from August 28 - September 3, 1983 in Noordwijkerhout, The Netherlands, received the gene­ rous support of the Charles F. Kettering Foundation Research Laboratory and the Tennessee Valley Authority. This support has helped research progress in this broad field of science by offering a forum both for the exchange of ideas and for scientific summary and discussion as captured over the last 10 years in each of the four books published previously. Although all previous meetings were well attended, the present conference was the largest so far. 550 scien­ tists from 60 different countries attended the "Leeuwenhorst Conference", re­ presenting the many different disciplines actively involved in research in this field: chemists, biochemists, molecular biologists, geneticists, microbiologists, plant physiologists, agriculturalists. A large number of them had to go through a difficult period to raise the necessary funds to attend. In addition, a parallel meeting of "policymakers" from Southeast Asia, Africa and South America was held under the auspices of Crosscurrents International Institute, Dayton, OR, USA and the United Nations University, Tokyo, Japan. These participants attended some of the scientific sessions to benefit from the vision of a number of scientists at the symposium.

Contenu

Application of Dinitrogen Fixation in Agriculture and Forestry.- The Application of Molecular Genetics in Agriculture.- Nitrogen-Fixing Trees in the Tropics: Potentialities and Limitations.- Biological Dinitrogen Fixation in Temperate Zone Forestry: Current Use and Future Potential.- Mircen Programmes and the Impact on the Application of Biological Nitrogen Fixation.- Poster Discussions 1A: Measuring Nitrogen Fixation.- Poster Papers (First Author Only).- Poster Discussions IB: Application of Biological Nitrogen Fixation for Increasing Crop Production.- Poster Papers (First Author Only).- Chemistry of Dinitrogen Fixation.- The Binding and Reactivity of Dinitrogen.- Hydrazido(l), 1,2-Hydrazido(2-), and Hydrazido(4-) Complexes of Tungsten(VI).- The Synthesis Structures and Electronic Properties of Fe-Mo-S Polynuclear Aggregates. Molecules of Elementary Structural Compliance with the Fe-Mo-S Aggregate of Nitrogenase.- Poster Discussions 2: Recent Progress in the Chemistry of Dinitrogen Fixation.- Poster Papers (First Author Only).- Enzymology of Nitrogenase.- Structure and Reactivity of Nitrogenase - An Overview.- Substrate Interactions with Nitrogenase and its Fe-Mo Cofactor: Chemical and Spectroscopic Investigations.- Iron-Sulfide Content and ATP Binding Properties of Nitrogenase Component II from Azotobactervinelandii.- The Mechanism of Substrate Reduction by Nitrogenase.- Nitrogenase from nifV Mutants of Klebsiellapneumoniae.- Poster Discussions 3: Enzymology of Nitrogenase.- Poster Papers (First Author Only).- Physiology of Diazotrophs.- Oxygen and the Physiology of Diazotrophic Microorganisms.- Regulation of Nitrogen Fixation in Photosynthetic Bacteria.- Energy Generation and Hydrogen Metabolism in Rhizobium.- Physiology and Biochemistry of N2-Fixation by Cyanobacteria.- Poster Discussions 4A: Physiology of Free-Living Diazotrophs Including Cyanobacteria and Azospirillum with Special Attention to NH4+ Metabolism, H2 Metabolism and O2 Protection.- Poster Papers (First Author Only.- Poster Discussions 4B: Metabolism of Rhizobium and Azotobacter.- Poster Papers (First Author Only.- Microbiology and Physiological Ecology of Diazotrophs.- Ecology and Microbiology of Symbiotic Diazotrophs.- The Ecology of Rhizobium in the Rhizosphere: Survival, Growth and Competition.- Effects of Drought and Salinity on Heterotrophic Nitrogen Fixing Bacteria and on Infection of Legumes by Rhizobia.- Response of Cereal and Forage Grasses to Inoculation with N2- Fixing Bacteria.- Ultrastructure and Nitrogenase Activity of Frankia Grown in Pure Culture and in Actinorrhizae of Alnus, Colletia, and Datisca spp..- Poster Discussions 5A: Stem-Nodulated Legumes and Nitrogen-Fixing Trees.- Poster Papers (First Author Only.- Poster Discussions 5B: Frankia Symbiosis.- Poster Papers (First Author Only.- Specificity in Symbiotic Dinitrogen Fixation.- Recent Ideas on the Physiology of Infection and Nodulation.- Preinvasion Events in Legume/Rhizobium Symbiosis.- The Polysaccharides and Oligosaccharides of Rhizobium and their Role in the Infection Process.- Poster Discussions 6: Recognition.- Poster Papers (First Author Only).- Physiology of Infected Plants.- Carbon Metabolism in the Legume Nodule.- The Cellular and Intracellular Organization of the Reactions of Ureide Biogenesis in Nodules of Tropical Legumes.- Energy Metabolism in Nodulated Roots.- The Unique Properties of the Symbiotic Anabaenaazollae in the Water Fern Azolla: Metabolism and Intracellular Recognition.- Oxygen, Hemoglobins, and Energy Usage in Actinorhizal Nodules.- The Role of Peribacteroid Membrane in Legume Root Nodules.- Symbiotic Nitrogen Fixation Involving Rhizobium and the Non-Legume Parasponia.- Poster Discussions 7A: Photosynthesis and Hydrogen Metabolism in Relation to Nitrogenase Activity of Legumes.- Poster Papers (First Author Only).- Poster Discussions 7B: Environmental Effects on Nodulated Plants.- Poster Papers (First Author Only).- Plant Genes Involved in Dinitrogen Fixation.- Leghemoglobin and Nodulin Genes: Two Major Groups of Host Genes Involved in Symbiotic Nitrogen Fixation.- Nitrogen and Carbon Assimilation in Medicagosativa Mediated by Host Plant Genes for Nodule Effectiveness.- The soybean leghemoglobin genes.- Expression of Nodulin Genes During Nodule Development from Effective and Ineffective Root Nodules.- Poster Discussions 8: Plant Genes Involved in Nodulation and Symbiosis.- Poster Papers (First Author Only).- Bacterial Genetics.- Advances in the Genetics of Free-Living and Symbiotic Nitrogen Fixing Bacteria.- Molecular Cloning and Organisation of Genes Involved in Symbiotic Nitrogen Fixation in Different Rhizobium Species.- Regulation of the Nitrogen Fixation (nif) Genes of Klebsiellapneumoniae and Rhizobiummeliloti: Role of Nitrogen Regulation (ntr) Genes.- Transcriptional Control of the nif Regulon in Klebsiellapneumoniae.- Aspects of Genetics of Azotobacters.- Organization and Transcription of Nitrogenase Genes in the Cyanobacterium Anabaena.- The Expression of Sym-Plasmids and Ti Plasmids in Rhizobia and Agrobacteria.- Poster Discussions 9A: Organization of Rhizobium Symbiotic Genes.- Poster Papers (First Author Only).- Poster Discussions 9B: Rhizobium Plasmids.- Poster Papers (First Author Only).- Poster Discussions 9C: Nif Genetics of Free-Living Diazotrophs.- Poster Papers (First Author Only).- Author Index.