Edited by David J. Bennett and Richard C. Jennings.
Published by Cambridge University Press, New York (US)
Summary of Part II: New Genetic crops across the emerging world
Prof Christopher J. Leaver (St John’s College, University of Oxford) commences the introductory chapter of the second part of the bock by recalling, once again, that the world’s population will reach 9 billion people by 2050. He states that each hectare of arable land in 2050 will need to feed five people compared to just two in 1960. This will coupled to decreased water availability, increased and changing biotic stress, and environmental pollution, loss of biodiversity, urbanisation and dietary upgrading. Prof Leave presents a set of interesting figures concerning the current poverty in Africa and elsewhere: 250 million people in Africa, about 25% of the total, do not have enough food to meet their daily calorific needs. Growing more from less is needed to eliminate/reduce present and future food insecurity. Prof Leave argues that sustainable intensification can accomplish the necessary increase in crop yields while preserving the environment and minimizing the effects of climate change. In addition, he says that available tools such as “-omics technologies” should be evaluated and, subject to appropriate and realistic biosafety regulation, those that are more effective need to be deployed.
Chapter 7 by Prof Diran Makinde (Director of African Biosafety Network of Expertise, Senegal) reviews the status of crop biotechnology and biosafety in Africa. Each year, insect pests can destroy 90% of some commodities. In the section titled “NEEDS”, Prof Makinde shows that the low technology input into farming is one of the reasons for the stagnation of African farmers’ yields in the last 30 years. He is convinced that biotechnology can help Africa. Despite the fact that GM crops confer agronomic, environmental, nutritional and health benefits, only three African countries have commercialized GE crops, namely South Africa, Burkina Faso and Egypt. Nevertheless, a good number of countries are conducting field trials: South Africa (10 field trials), Uganda (7), Kenya (6), Egypt (5), Burkina Faso (2) and Zimbabwe (1). In his conclusions, the author calls for an integration between regional biotechnology research developments and in the biosafety approaches of individual countries.
In Chapter 8, Prof Eduardo Trigo (Univerisy of Wisconsin) and Dr Eugenio Cap (INTA) look into the economic and non-pecuniary benefits (eg. on the environment) to the domestic economy and global consumers derived from the adoption of GM crops in Argentina. The authors highlight the importance of having already placed the institutions required to deal with the technology transfer and diffusion process when GM crops were made available to this country. This fact provoked an early and rapid adoption of GM crops resulting in an absolute success in Argentina. However, the authors claim that potential risks implied in the massive transformation of farming systems cannot be ignored, such as monoculture practices, relatively low fertilization levels and the long-term effect of the continued “export” of phosphorous (soil nutrient).
Prof Lu Bao-Rong (Fundan University) authorizes Chapter 9 which is devoted to earlier experiences and future prospects for agribiotechnology in China. By 2030, there may be a shortage of 120-170 million tons of food supplies in this country if the current trend on water and land availability and the likely future scenarios for climate change, rapid industrialisation, urbanisation and economic development are not reversed. There is a need for enhancing crop productivity per unit of area significantly in an environmental friendly and resource cost-effective manner. The appropriate utilisation of germplasm combined with the adoption of biotechnology may provide greater opportunities to considerably increase crop productivity in China.
Prof Bao-Rong reviews the utilisation of germplasm and breeding technology for the fruitful impact on rice production during the last decades. However, the “high-input and high-output” model that worked as basis for this achievement needs to be turned into a more environmental friendly approach, the author says. The rice story is not repeated in the case of GM cotton. Chinese transgenic cotton is the most successful transgenic crop in use in agricultural production. The introduction of Bt cotton in this country has saved the Chinese cotton industry, in addition to its positive ecological impacts. Simultaneously, this great success of Bt cotton has promoted the research, development and application of other important transgenic crops and vegetables. Prof Bao-Rong calls for proper biosafety assessment and management to tackle any potential issues.
Chapter 10 is written by Prof Chavali Kameswara (retired from Bangalore University) and brings an Indian perspective to the food security, poverty and malnutrition. He contrasts the success of commercialization of Bt cotton with the current impasse facing the adoption of a range of genetically modified food crops in India, including Bt brinjal and Golden Rice, due to widespread activism against GM crops.
Prof Pamela Ronald (University of California, Davis) (Chapter 11) describes how genetically improved crops in combination with good agricultural practices have contributed to sustainable agriculture.
Genetically engineered crops, producing a toxin from Bacillus thuringiensis (Bt) have been developed to control pests caused by insects that feed inside plants, such as the European corn-borer and the pink bollworm. Use of Bt crops has resulted in a significant decrease in insecticide use in the US. For instance, in Arizona it resulted in a 70% reduction and a corresponding saving of $200 million. Moreover, use of Bt crop resulted in increased biodiversity, as demonstrated by the more abundant presence of non-target invertebrates in Bt cotton and Bt maize. To date, strategies to avoid pest resistance consist of planting refuge crops and the release of sterile insects.
The development and use of herbicide-tolerant crops, engineered for tolerance to newer, non-toxic herbicides such as glyphosate, resulted in a significant decrease in toxic herbicide use. For instance, an 83-100% reduction of toxic herbicide use (class II and III) was observed in Argentina. Furthermore, herbicide tolerant crops have contributed to low-till or no-till agricultural practices, thereby reducing soil erosion and fuel consumption in case of tractor-tilling. To avoid the evolution of resistant weeds, sustainable management systems have to be implemented, which is supported by the development of crops resistant to more than one herbicide.
Future crops that will contribute to enhance sustainable global agriculture include Honeysweet, a plum pox virus resistant plum variety and the introduction of drought tolerant maize, the most important African staple food crop.
In Chapter 12 titled ‘Nutritional enhancement by biofortification of staple crops’, Dr. Adrian Dubock emphasizes the importance of micronutrients, i.e. vitamins and minerals, for human development. For instance, vitamin A deficiency is widespread in developing countries and is the largest cause of childhood blindness with 170-230 million children affected annually. To address micronutrient deficiencies, several strategies have been adopted, including industrial fortification (e.g. iodine in salt), micronutrient supplementation (providing micronutrient containing tablets) and the biofortification of crops, such as the genetically engineered carotenoid producing rice variety Golden Rice. Biofortification work has been facilitated over the last decades by progress in the mapping of plant genomes, gene discovery and the elucidation of biosynthetic pathways.
Dr. Dubock gives an overview of the commercial international agricultural product development of Golden Rice, in which he was involved as negotiator for Zeneca. Data were generated proving that Golden Rice is as effective as vitamin A capsules. A major obstacle in the development of Golden Rice was human suspicion of genetically engineered crops, especially in Europe where there is less empathy for nutrition issues in developing countries. However, resource-poor growers and consumers have no concerns how it is created as long as the rice is more nutritious and there is no additional cost associated with its cultivation and use.
Another important crop in developing countries, especially in Africa, is cowpea. Chapter 13, authored by Prof. Larry Murdock (Purdue University), Prof. Idah Sithole-Niang (University of Zimbabwe) and T.J.V. Higgings, honorary fellow at CSIRO Plant Industry (Australia), describes the need for and the development of insect-resistant Bt cowpea. Insect pests are responsible for huge losses in cowpea yields, in particular Maruca podborer (MPB) in the field and the cowpea bruchid post-harvest. Advances in cowpea cultivation are limited due to underinvestment in agricultural research, caused by (1) limited international trade in cowpea; (2) the focus of African nations on developing cities; (3) the inefficient regulatory processes and (4) little attention to minor crops by international institutions.
Since the development of a cowpea transformation system, research strategies have focused on developing Bt cowpea, conferring resistance towards Maruca Podborer (MPB). Field trials conducted in sub-Saharan Africa delivered promising results. However, the negative European attitude towards agricultural biotechnology has an impact on the legacy on Africa. Moreover, a workable system will have to be created in Africa to ensure seed access, quality control and stewardship. The authors conclude that Bt cowpea enables an increased cowpea production in Africa at a lower cost and hence can contribute to a better life for millions of poor Africans.
Prof. Jonathan Gressel presents in Chapter 14 a solution for protein sufficiency in aquaculture by the development of transgenic marine algae. Huge efforts are being made to replace fishmeal with other protein sources and it was demonstrated that algae can accomplish that partially. The potential for algae feed is immense: algal yields are high, the whole plant is consumed (not only seeds), industrial waste carbon dioxide can maximise algal growth and the natural oil found in algae is rich in omega-3 fatty acids. Limitations are the high production and harvesting costs and the fact that domestication of the algae is needed. Domestication in our present crops took thousands of years to accomplish. Therefore, in order to domesticate algae rapidly and to obtain algae ideal for feeding, genetic engineering is required. An overview of genes needed as traits are summarized in the chapter.
To obtain algae with very high growth rates, adequate amounts of carbon dioxide have to be supplied. For instance, this can be achieved by using gas from coal-fired power plants or by separating it from natural gas. Culturing algae is already near being cost-effective, allowing it to be commercialised. When optimal traits are added through genetically engineering and production systems are optimized, algae will be competitive with feed grains and can contribute to achieve food security for our growing population.