Management of Biological Nitrogen Fixation for the Development of More Productive and Sustainable Agricultural Systems

Author: International Rice Research Institute

Publisher: Int. Rice Res. Inst.

ISBN: 9780792334132

Category: Nature

Page: 291

View: 359

The subsistence agriculture of the pre-chemical era efficiently sustained the nitrogen status of soils by maintaining a balance between N loss and N gain from biological nitrogen fixation (BNF): the microbial conversion of atmospheric N to a form usable by plants. This was possible with less intensive cropping, adaptation of rational crop rotations and intercropping schemes, and the use of legumes as green manure. Modern agriculture concentrates on maximum output, however, overlooking input efficiency; It is not sustainable. Intensive monocropping, with no or inadequate crop rotations or green manuring, together with the excessive use of chemical N fertilizers, results in an imbalance between N gain and N loss. The losses are often larger than the gains, and soil N status declines. The challenge is to sustain soil N fertility in many different tropical and temperate farming systems operating at high productivity levels. This requires judicious integration of BNF components, maintaining a good balance between N losses and gains. In this book, papers on BNF in crop forage and tree legumes are augmented with discussions of integrated farming systems involving BNF, soil and N management, and recycling of legume residues. BNF by non-legumes are discussed, and attempts to transform cereals into nodulating plants are critically reviewed. Advances in the development of novel methodologies to understand symbiotic relations and to assess N 2 fixation in the field are described, and means are presented to enhance BNF through plant and soil management or breeding and selection. Problems encountered in exploiting BNF under field conditions are examined, as are promising approaches to improving BNF exploitation.
Biological Nitrogen Fixation and Sustainability of Tropical Agriculture

Author: African Association for Biological Nitrogen Fixation. Conference

Publisher: IITA

ISBN: 0471935603

Category: Science

Page: 512

View: 366

Biological nitrogen fixation in tropical agrosystems: twenty years of biological nitrogen fixation research in Africa; Sustainable agriculture: definition and measurement; Biological nitrogen fixation systems in tropical ecosystems: an overview; A protocol for screening legumes as soil-improving crops; The sustenance of tropical agriculture with multipurpose azolla; Facteurs pedoclimatiques limitant la lixation biologique l'azole; Response of some tropical nitrogen-fixing woody legumes to drought and inoculation with mycorrhiza; Improvement to the Phaseolus/Rhizobium symbiosis, with particular reference to the Caribbean region; Effect of pest management systems on biological nitrogen fixation; Agronomic evaluation of a rock phosphate as a phosphorus source for Leucaena leucocephala grown on an utisol; Nodulation of soybean grown under field conditions and inoculated with Bradyrhizobium japonicum strains; Effect of fertilization and Rhizobium inoculation on the growth of Leucaena and Gliricidia on an alfisol in south-western Nigeria; Early growth and nodulation in Leucaena and Gliricidia and the effects or pruning on biomass productivity; Comparative stude on the growth and productivity of Sesbania and Leucaena in the Central Plateau region, Rwanda; Supernoculation and non-nodulation mutants of soybean; Genetically improved rhizobia and their use in agriculture; Sustainability of nitrogen-fixing cropping systems: Nodulation and nitrogen fixation and transfer in a cowpea/rice cropping system; The role of legumes in sustaiing soil productivity and controlling soil erosion; Fitting soil-improving legumes into inland valley rice-baes cropping systems in West Africa; Herbage yield and soil fertility restoration potential of some tropical forage legumes.
Biological Nitrogen Fixation, Sustainable Agriculture and the Environment

Author: Yi-Ping Wang

Publisher: Springer Science & Business Media

ISBN: 9781402035708

Category: Technology & Engineering

Page: 445

View: 922

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.
Biological Nitrogen Fixation: Towards Poverty Alleviation through Sustainable Agriculture

Author: Felix D. Dakora

Publisher: Springer Science & Business Media

ISBN: 9781402082528

Category: Science

Page: 392

View: 774

Poverty is a severe problem in Africa, Asia, South America and even in pockets of the developed world. Addressing poverty alleviation via the expanded use of biological nitrogen fixation in agriculture was the theme of the 15th International Congress on Nitrogen Fixation. Because nitrogen-fixation research is multidisciplinary, exploiting its benefits for agriculture and environmental protection has continued to attract research by diverse groups of scientists, including chemists, biochemists, plant physiologists, evolutionary biologists, ecologists, agricultural scientists, extension agents, and inoculant producers. The 15th International Congress on Nitrogen Fixation was held jointly with the 12th International Conference of the African Association for Biological Nitrogen Fixation. This joint Congress was hosted in South Africa at the Cape Town International Conv- tion Centre, 21–26 January 2007, and was attended by about 200 registered participants from 41 countries world-wide. During the Congress, some 100 oral and approximately 80 poster papers were presented. The wide range of topics covered and the theme of the Congress justifies this book’s title, Nitrogen Fixation: Applications to Poverty Alleviation.
Biological Nitrogen Fixation: Towards Poverty Alleviation through Sustainable Agriculture

Author: Felix Dakora

Publisher: Springer

ISBN: 9048119472

Category: Science

Page: 392

View: 389

Poverty is a severe problem in Africa, Asia, South America and even in pockets of the developed world. Addressing poverty alleviation via the expanded use of biological nitrogen fixation in agriculture was the theme of the 15th International Congress on Nitrogen Fixation. Because nitrogen-fixation research is multidisciplinary, exploiting its benefits for agriculture and environmental protection has continued to attract research by diverse groups of scientists, including chemists, biochemists, plant physiologists, evolutionary biologists, ecologists, agricultural scientists, extension agents, and inoculant producers. The 15th International Congress on Nitrogen Fixation was held jointly with the 12th International Conference of the African Association for Biological Nitrogen Fixation. This joint Congress was hosted in South Africa at the Cape Town International Conv- tion Centre, 21–26 January 2007, and was attended by about 200 registered participants from 41 countries world-wide. During the Congress, some 100 oral and approximately 80 poster papers were presented. The wide range of topics covered and the theme of the Congress justifies this book’s title, Nitrogen Fixation: Applications to Poverty Alleviation.
Biological Fixation of Nitrogen for Ecology and Sustainable Agriculture

Author: Andrzej Legocki

Publisher: Springer Science & Business Media

ISBN: 9783642591129

Category: Science

Page: 328

View: 441

Biological nitrogen fixation (BNF) - the conversion of molecular nitrogen into ammonia - is one of the most important reactions in ecology and agriculture. It is performed exclusively by microbes (prokaryotes) that live in symbiosis with plants. This book summarizes the latest research on this reaction, the participating microbes and the genetics of how their relevant genes could be transferred into the plants. In the light of a more sustainable and less ecologically damaging agriculture, this is becoming an increasingly pressing issue.
Biological Nitrogen Fixation for Sustainable Agriculture

Author: J.K. Ladha

Publisher: Springer Science & Business Media

ISBN: 9789401709101

Category: Nature

Page: 212

View: 358

Chemical fertilizers have had a significant impact on food production in the recent past, and are today an indispensable part of modern agriculture. On the other hand, the oil crisis of the 1970s and the current Middle East problems are constant reminders of the vulnerability of our fossil fuel dependent agriculture. There are vast areas of the developing world where N fertilizers are neither available nor affordable and, in most of these countries, balance of payment problems have resulted in the removal of N fertilizer subsidies. The external costs of environmental degradation and human health far exceed economic concerns. Input efficiency of N fertilizer is one of the lowest and, in turn, contributes substantially to environmental pollution. Nitrate in ground and surface waters and the threat to the stability of the ozone layer from gaseous oxides of nitrogen are major health and environmental concerns. The removal of large quantities of crop produce from the land also depletes soil of its native N reserves. Another concern is the decline in crop yields under continuous use of N fertilizers. These economic, environmental and production considerations dictate that biological alternatives which can augment, and in some cases replace, N fertilizers must be exploited. Long-term sustainability of agricultural systems must rely on the use and effective management of internal resources. The process of biological nitrogen fixation offers and economically attractive and ecologically sound means of reducing external nitrogen input and improving the quality and quantity of internal resources. In this book, we outline sustainability issues that dictate an increased use of biological nitrogen fixation and the constraints on its optimal use in agriculture.