The Nitrogen Fixation And Its Research In China

Nitrogen Fixation by symbiotic organisms is considered an important contribution to the solution of food problems throughout the world. For manyyears, Chinese scientists have focused their research in this area. Today more than half of the total nitrogen fertilizers applied are from biological fixation sources. The editor is an international renowned scientist at the Chinese Academy of sciences. He has brought together contributions from various research fields in China and Europe.Together they present the state-of-the-art in nitrogen-fixation research. The studies range from actino- mycete fixation induced in various genera andspecies of plants, mechanisms and chemical modeling of enzyme systems togenetical engineering of organisms.

Nitrogen Fixation by symbiotic organisms is considered an important contribution to the solution of food problems throughout the world. For manyyears, Chinese scientists have focused their research in this area. Today more than half of the total nitrogen fertilizers applied are from biological fixation sources. The editor is an international renowned scientist at the Chinese Academy of sciences. He has brought together contributions from various research fields in China and Europe.Together they present the state-of-the-art in nitrogen-fixation research. The studies range from actino- mycete fixation induced in various genera andspecies of plants, mechanisms and chemical modeling of enzyme systems togenetical engineering of organisms.

The 14th International Nitrogen Fixation Congress was held in Beijing, China from October 27th through November 1st, 2004. This volume constitutes the proceedings of the Congress and represents a compilation of the presentations by scientists from more than 30 countries around the World who came to Beijing to discuss the progress made since the last Congress and to exchange ideas and information. This year marked the 30th anniversary of the first Congress held in Pullman, Washington, USA, in 1974. Since then, this series of Congresses has met five times in North America (three in the United States and once each in Canada and Mexico), once in South America (Brazil), four times in Western Europe (once each in Spain, The Netherlands, Germany and France), once in Eastern Europe (Russia), and once in Australia; and now for the first time in Asia. China was a most appropriate choice because China is a big country with the largest population in the World, about 1. 3 billion people, which is about 22% of the World’s population. It is traditionally an agricultural country, even though China has only 7% of the available farming land. This situation explains why agriculture and its productivity are major issues for the Chinese people, its government and the scientists in the field.

Diazotrophic bacteria convert atmospheric nitrogen to plant-useable form and this input of nitrogen through biological fixation is of great agronomic importance. The contributions presented in this volume relate to free-living nitrogen fixers and the diazotrophs associated with plants. Symbiotic association of Frankia with non-legumes and cyanobacterial associations are also discussed. Research topics covered in this volume include the biochemistry and genetics of diazotrophs, recent developments in improvement of plant-microbe interactions and their molecular basis, the use of molecular probes in taxonomy and ecology of diazotrophs and reports on field applications, agronomic importance and improvement in methodologies for assessing their contribution to plants. This book provides valuable information not only for researchers working in the field of biological nitrogen fixation but also for biochemistry, molecular biologists, microbiologists and agronomists.

For 31 years, the North American Symbiotic Nitrogen Fixation Conference (for merly Rhizobium Conference) has been a forum for scientists and graduate students to discuss their research advances, extending from basic aspects to agricultural appli cations, and dealing with topics ranging from bacterial genetics and metabolism to plant genetics and physiology. Nitrogen fixation, being a major life-supporting process on this planet, has attracted the interest of researchers for more than one century. Nitrogen fixation is responsible for the conversion of "inert" dinitrogen (N ) gas from the atmos z phere into usable ammonia, replacing the fixed nitrogen constantly being lost to the atmosphere by the denitrification process. Worldwide agricultural productivity is deter mined by the availability of fixed nitrogen in all its forms, which the continually increas ing human population depends upon for survival. An international momentum is developing in the use of biofertilizers to improve legume and non-legume crop yields and in the study of genomics in this area. New studies are being undertaken in several laboratories to study novel nitrogen-fixing systems, including non-legume crops. The North American Conferences on Symbiotic Nitrogen Fixation have periodically chronicled the advances in our knowledge of this area. For the first time, this conference was held in Mexico. Thus, all three North Amer ican countries have been hosts for this event. This year conference brought nearly 200 scientists from 18 different countries presenting lectures and over 80 posters.

Biological nitrogen fixation has essential role in N cycle in global ecosystem. Several types of nitrogen fixing bacteria are recognized: the free-living bacteria in soil or water; symbiotic bacteria making root nodules in legumes or non-legumes; associative nitrogen fixing bacteria that resides outside the plant roots and provides fixed nitrogen to the plants; endophytic nitrogen fixing bacteria living in the roots, stems and leaves of plants. In this book there are 11 chapters related to biological nitrogen fixation, regulation of legume-rhizobium symbiosis, and agriculture and ecology of biological nitrogen fixation, including new models for autoregulation of nodulation in legumes, endophytic nitrogen fixation in sugarcane or forest trees, etc. Hopefully, this book will contribute to biological, ecological, and agricultural sciences.

The First Asia --- Pacific Conference on Agricultural Biotechnology was held in Beijing, China on 20-24, August, 1992. Over half the population in the world is in the Asian and Pacific Region. With an increasing population and decreasing farming lands, it is important to develop agricultural biotechnology for improvement of the productivity, profitability and stability of the farming system. The Conference's main objectives were to bring together scientists working in different fields of agricultural biotechnology to stimulate discussion on this important process and to have an appraisal of the most recent studies concerning genetic manipulation of plants, plant cell and tissue culture, plant gene regulation, plant-microbe interaction, animal biotechnology etc. The Conference was attended by 391 scientists from different countries and regions. This volume presents the contributions of the lectures and a selected number of posters, which are an up-to-date account of the state of knowledge on agricultural biotechnology. The book provides a valuable reference source not only for specialists in agricultural biotechnology, but also for researchers working on related aspects of agronomy, biochemistry, genetics, molecular biology, microbiology and animal sciences. It is with great pleasure to acknowledge the contributions of the authors in assuring the prompt publication of this volume. We would also extend our sincere thank to Kluwer Academic Publishers for the publication of these proceedings.