The introduction to these two volumes reminds us that ‘… global agriculture feeds a population of approximately 6·4 billion and delivers a wide range of additional services. These range from waste management and water purification through delivery of fuel, fibre and chemical products to recreation and the conservation of biodiversity.’ The editors also remind us in their introduction that world human population is projected to rise to 8·5–9 billion by 2045–50. Projections of climate change suggest that there will be significant negative impacts on crop and animal production, particularly in the subtropics and tropics. At the same time, demand for animal products in developing countries is growing fast so that an extra 300 Mt of grain will be needed by 2050 to meet this need alone. Urban and industrial water use is reducing water availability for agriculture in many regions, and harvesting solar energy for bio-fuels and industrial feedstocks will further reduce land available for food production. The two volumes reviewed here contain 29 review papers on ‘sustainable’ agriculture. The definition of ‘sustainable’ varies between papers, but is probably most realistically viewed as agricultural practice that can be maintained for a long period with minimal inputs, and minimal damage to the environment.

The rich developed economies have achieved huge increases in agricultural output in the last 50 years, but with profligate inputs of energy, fertilizer and water. The intensification which contributed to this success has often resulted in increased disease problems, which have been controlled by the use of chemicals. Some of these compounds have been detrimental to the environment, and all too often the disease organisms being targeted have developed resistance. In addition, global trade and climate change have spread pests and diseases to new areas. With these problems, and in an era of climate change and diminishing natural resources, coupled with increasing demand for those resources, it is imperative that we rethink our agricultural practices.

The 29 review papers in these two volumes provide good briefing for just such a rethink. They cover many relevant topics, outlining current and historical agricultural practices in both rich and poor countries, including animal and plant integrated systems; plant and animal breeding techniques; biological control of pests including GM crops; transgenesis and gene knockout in animals and the potential of these techniques for agriculture, science and human health; manipulation of plant proteins and fats to improve their nutritive value; development of plant resistance to pesticides; plant chemistry and the signals perceived by pests offering the potential of pest management; biosecurity; electronic biosensors; water use and pollution; greenhouse gas emissions (it is a pleasure to see that ruminants are not held to be totally to blame); and carbon sequestration. Many of the papers are by authors who, to judge from their departments and institutions, arrive at a view of agriculture from the perspective of other disciplines, in particular the ecology of what would have been traditionally viewed as ‘non-farming’. The publication gains from this, for traditionally agriculture was – and in many poor countries still is – an integration and manipulation of natural systems rather than the sledge hammer approach of some of the specialized and intensive production systems developed by rich countries.

Agriculture is entering a period of huge change driven by the need to feed the growing human population, and the demand for new products such as bio-fuels. Land availability, energy, fertilizer and water supplies will be under ever-increasing pressure and will affect both crop and animal production. Indeed, the recent increases in cereal prices, and huge increases in oil prices, post date the writing of the papers of this publication. The future impact of climate change on ambient temperatures, rainfall distribution, flooding, sea level rise and severe storms is only beginning to be perceived and modelled. The magnitude of human activities on the planet is such that we have responsibilities which now encompass the preservation of our very rare and very beautiful world. Thus, our vision has to extend beyond agricultural ‘production’ as some of the papers in these volumes state or imply. We have tools beyond the dreams of previous generations of scientists – analytical techniques, animal and plant breeding, gene identification and manipulation, huge computing power, satellite communication and satellite navigation (enabling precise positioning of plants and fertilizer) to name only a few. The potentials of these tools are limited only by our imagination. However, it is important that we apply these tools with wisdom which must extend beyond mere commercial expediency.

This wisdom needs to be based on a holistic understanding of the biology involved, and these two volumes provide a good and stimulating introduction to many aspects of that understanding. That understanding must be strengthened and enhanced by scientific research. It is paradoxical that in a period of unprecedented change and rate of change in agriculture, agricultural teaching and research in the rich countries is being progressively diminished. It is essential that as well as the excellent and valuable commercial research and development currently in progress, that there be a substantial increase in state funded research whose vision and wisdom can extend beyond commercial imperatives.