Advances in Legume-based Agroecoystem for Sustainable Intensification explores current research and future strategies for ensuring capacity growth and socioeconomic improvement through the utilization of legume crop cultivation and production in the achievement of sustainability development goals (SDGs). Sections cover the role of legumes in addressing issues of food security, improving nitrogen in the environment, environmental sustainability, economic-environmentally optimized systems, the importance and impact of nitrogen, organic production, and biomass potential, legume production, biology, breeding improvement, cropping systems, and the use of legumes for eco-friendly weed management. This book is an important resource for scientists, researchers and advanced students interested in championing the effective utilization of legumes for agronomic and ecological benefit. - Focuses on opportunities for agricultural impact and sustainability - Presents insights into both agricultural sustainability and eco-intensification - Includes the impact of legume production on societal impacts such as health and wealth management

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.

Table 1. Global allocation of arable land between different com modities Globally, cereal cropping dominates cultivated land Commodities' Proportion of land area use (around 50% of total area, Table 1). The remain (%) ing arable land is used for production of oilseed, fibre, or food and cash crops. In addition, vast areas are Cereals maintained under temporary or permanent pasture for Wheat 16 forage production (2-3 fold greater than the total area Rice 10 under cultivation and permanent crop; Table 1, Fig. Maize 9 1). All cultivated crops, except for legumes (pulses All other cereals 13 and legume oil seeds) require the soil to provide rel Total 48 atively large amounts of nitrogen (N). It is necessary for the three most important cereals, wheat (Triticum Legumes aestivum), rice (Oryza sativa) and maize (Zea mays), Legume pulses 5 to take up 20 to 40 kg soil N ha -lover a period of 3 Legume oilseeds 6 to 5 months to satisfy the N requirements of the seed and supporting vegetative structure for each tonne of Total II grain produced (e. g. Fig. 2; Myers, 1988). Produc tive pastures on the other hand may assimilate> 100 Other crops I kg N ha- each annum, of which 50 to 90% will be Other oilseeds 6 consumed by livestock in intensively grazed systems Beverages / Tobacco 7 (Ledgardy, 1991; Thomas, 1995).

The world population will grow more rapidly during the few coming years. This must be accompanied by a parallel increase in the agricultural production to secure adequate food. Sustainability considerations mandate that alternatives to chemical nitrogen fertilizers must be urgently sought. Biological nitrogen (N2) fixation, a microbiological process which converts atmospheric N2 into a plant-usable form, offers this alternative. Among these renewable sources, N2-fixing legumes offer an economically attractive and ecologically sound means of reducing external inputs and improving internal resources. Environmental factors such as drought, elevated temperature, salinity, soil acidity and rising CO2 are known to dramatically affect the symbiotic process and thus play a part in determining the actual amount of nitrogen fixed by a given legume in the field. Understanding how nodule N2 fixation responds to the environment is crucial for improving legume production and maintaining sustainability in the context of global change. In this thoughtful and provocative new Brief, we provide critical information on how current and projected future changes in the environment will affect legume growth and their symbiotic N2 fixing capabilities. Each section reviews the main drivers of environmental change on the legume performance that include drought, elevated temperature, salinity and rising CO2, and soil acidity. Importantly we discuss the molecular approaches to the analysis of the stress response in legumes and the possible biotechnological strategies to overcome their detrimental effects.

This volume covers all aspects of fundamental and applied nitrogen-fixation research, extending from biochemistry and chemistry through genetics, regulation and physiology to agricultural practice and environmental impact. It describes recent progress on studies of potential catalysts for nitrogen fixation; how the N2-fixing process is regulated in living cells; the use and impact of genetics and genomics on our understanding of the biological process; the wide variety of associations of nitrogen-fixing microbes with plants, including the formalized Rhizobium-legume and actinorrhizal associations as well as the less formalized associative and endophytic interactions; and the impact of nitrogen fixation in agriculture and forestry, including its effect on the environment. This volume provides an up-to-date referenced source, which can be readily accessed by all practicing and otherwise interested proponents of nitrogen fixation research, including those with related interests in the areas of plant and microbial science, genomics, plant-microbe interactions, genetics and regulation, plant growth and biocontrol, agriculture, forestry, ecology, taxonomy and evolution.

Incorporating contributions from microbiologists, molecular biologists, plant breeders and soil scientists this volume reports the results and recommendations of an FAO/IAEA meeting of twelve experts on biological nitrogen fixation. This volume will be invaluable to scientists working on nitrogen fixation, soil microbiology, agronomy and crop production as well as farm advisers and extension specialists. Maximising the Use of Biological Nitrogen Fixation in Agriculture is unique in that it: -reviews the latest thinking on various aspects of biological nitrogen fixation technology and applications; -reviews the possibilities in enhancing nitrogen fixation in various cropping systems; -shows ways how biological nitrogen fixation can be used to enhance crop production; -considers the applicability of these technologies to small farmers in developing countries.

Continued population growth, rapidly changing consumption patterns and the impacts of climate change and environmental degradation are driving limited resources of food, energy, water and materials towards critical thresholds worldwide. These pressures are likely to be substantial across Africa, where countries will have to find innovative ways to boost crop and livestock production to avoid becoming more reliant on imports and food aid. Sustainable agricultural intensification - producing more output from the same area of land while reducing the negative environmental impacts - represents a solution for millions of African farmers. This volume presents the lessons learned from 40 sustainable agricultural intensification programmes in 20 countries across Africa, commissioned as part of the UK Government's Foresight project. Through detailed case studies, the authors of each chapter examine how to develop productive and sustainable agricultural systems and how to scale up these systems to reach many more millions of people in the future. Themes covered include crop improvements, agroforestry and soil conservation, conservation agriculture, integrated pest management, horticulture, livestock and fodder crops, aquaculture, and novel policies and partnerships.

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.

Research works on biologica nitrogen fixation for sustainable agriculture.