Sustaining Global Food Security: The Nexus of Science and Policy

By CSIRO PUBLISHING

Population growth alone dictates that global food supplies must increase by over 50% in coming decades. Advances in technology offer an array of opportunities to meet this demand, but history shows that these can be fully realised only within an enabling policy environment. Sustaining Global Food Security makes a compelling case that recent technological breakthroughs can move the planet towards a secure and sustainable food supply only if new policies are designed that allow their full expression.

Bob Zeigler has brought together a distinguished set of scientists and policy analysts to produce well-referenced chapters exploring international policies on genetic resources, molecular genetics, genetic engineering, crop breeding and protection, remote sensing, the changing landscape of agricultural policies in the world’s largest countries, and trade. Those entering the agricultural sciences and those who aspire to influence public policy during their careers will benefit from the insights of this unique set of experiences and perspectives.

• Language: English
• Publisher: CSIRO PUBLISHING
• Release date: Oct 9, 2019
• ISBN: 9781486308101

Book preview

SUSTAINING GLOBAL FOOD SECURITY

THE NEXUS OF SCIENCE AND POLICY

Editor: Robert S. Zeigler

For Willow, Pearl, Sylvie and Jack: The next generation

SUSTAINING GLOBAL FOOD SECURITY

THE NEXUS OF SCIENCE AND POLICY

Editor: Robert S. Zeigler

Copyright The Authors 2019. All rights reserved.

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Front cover: (clockwise from top left) maize (photo: Wolf Avni/Shutterstock); Rwandan girl looking over field (photo: Vadim Nefedoff/Shutterstock); fields in Kenya (photo: Sopotnicki/Shutterstock); Indian family harvesting wheat (photo: Rawpixel.com/Shutterstock); terraced rice paddy fields in Vietnam (photo: Chatrawee Wiratgasem).

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Contents

Preface

List of contributors

An introduction to the global food security, technology and policy nexus

Robert S. Zeigler

Part 1 Tapping and creating genetic resources

1Systematic assessment for conservation and utilisation of crop genetic resources

Paula Bramel and Sarada Krishnan

2Crop species origins, the impact of domestication and the potential of wide hybridisation for crop improvement

Bikram S Gill, Bernd Friebe, Dal-Hoe Koo and Wanlong Li

3Technological and policy challenges to utilisation of plant genetic resources

Theo van Hintum and Martin Brink

4Oryza genome diversity: discovery, management and utilisation

Rod A. Wing

Part 2 Redesigning crop plants

5Reducing mineral and vitamin deficiencies through biofortification: progress under HarvestPlus

Howarth Bouis and Ross Welch

6Delivering biofortified crops in developing countries

Howarth Bouis, Jan Low and Robert S. Zeigler

7Fatty acids and pharmamolecules

Surinder Singh, Phil Larkin and Allan Green

8Resistant starch, large bowel fermentation and human health

David L. Topping

9Redesigning crop photosynthesis

Stephen P. Long, Steven Burgess and Isla Causton

Part 3 Modern plant breeding

10 Modern plant breeding: a perspective from the public sector in the United States

P. Stephen Baenziger

11 Improving the regulation and social acceptance of crop-protection and seeds products produced using new technologies: an industry perspective

Alan Raybould

Colour plates

12 Plant phenome to genome: a big data challenge

Robert T. Furbank, Xavier R.R. Sirault and Eric Stone

13 Incorporating stress tolerance in rice

Abdelbagi M. Ismail and Gary Atlin

Part 4 Managing the crop

14 Closing crop yield gaps around the world

R.A. Fischer

15 The soil microbiome and crop nitrogen nutrition in anaerobic systems: a case study in rice

J.K. Ladha and P.M. Reddy

16 Manipulating molecular interactions between hosts and pathogens for enhancing resistance and disease management

Barbara Valent and Jan E. Leach

17 Sustainable rice pest management: the role of agricultural policies

E.A. Heinrichs

18 A view of water management: from river basin to farm

Gilbert Levine and Randolph Barker

Part 5 Sustainable intensive systems

19 Remote sensing for sustainable agricultural management

Andy Nelson

20 A new public–private interface for staple crops: the Sustainable Rice Platform

Robert S. Zeigler and Achim Dobermann

21 Linking public goods with private interests: investing in performance at scale with smallholders and the private sector

A. J. Simons, H. Y. Shapiro and Robert S. Zeigler

Part 6 Major agricultural regions in transition

22 Agricultural growth, transformation and policies in China

Jikun Huang

23 Modern plant and agricultural sciences and public policies in India: creating a sustainable global food supply

Rita Sharma

24 Unlocking Africa’s agricultural potential

Akinwumi A. Adesina

25 Sub-Saharan agriculture in transition: the case of rice

Keijiro Otsuka

Part 7 Globalisation of food supply

26 The rapid transformation of food supply chains in developing and emerging economies with implications for farmers and consumers

Thomas Reardon and B. Minten

27 Social change and policies driving the transformation of consumption in the food systems

Joachim von Braun, Nicolas Gerber and Vicki Abresch

28 Trade as a means to meeting global food needs

Kym Anderson

Some closing thoughts

Robert S. Zeigler

Index

Preface

I agreed to put this book together because it helps me grapple with a concern I have had over much of my career. How can we better engage the policy and technological dimensions of our efforts to assure global food security? Since the late 1970s I have been engaged in some kind of agricultural research in developing countries. My research in Asia, Latin America and Africa focused on understanding and managing cereal diseases, mostly in rice. But very early on I began managing multidisciplinary research teams covering crop improvement, crop management, economics and the social sciences. Development economists and agricultural scientists view the world very differently, are prone to lively discussions when they are on speaking terms and sometimes forget that they are looking at the same world through different lenses.

It is my hope that students, early career scientists and policy makers will use this book as a resource for understanding the relationship between policy and technology. Scientists need to be aware from the beginning of their careers that their findings will play out within a policy environment. Appreciating that, perhaps some will be credible voices in the inevitable science policy debates. Likewise, policy makers should be aware of the incredible rate of scientific progress we are seeing today. More importantly, they should appreciate how available technologies – or their shortcomings – can determine the outcome of well-intentioned policies.

I was very fortunate throughout my career to have known and worked with those who played a major role in creating a world where food security has become almost a given. I was recruited into rice science by Peter Jennings, one of the creators of semi-dwarf rice varieties that were the foundation of the ‘Green Revolution’ in Asia and Latin America. I also enjoyed many conversations with Norman Borlaug, Nobel Peace Prize laureate in wheat breeding, near the end of his life. Both men trained as plant pathologists and made their marks through plant breeding, but they instilled in me a healthy respect for policy. They helped create modern rice and wheat varieties with much greater yield potential, but they recognised that without adequate water, fertiliser and markets to absorb additional production, this potential would not be realised. Major public policy measures were required to make the necessary investments in irrigation and transportation infrastructure, and credit and subsidy programs were developed to enable farmers to purchase improved seed and fertilisers. This exposure explains my first foray into the policy–technology arena that convened a dialogue between senior agricultural policy makers and research leaders in Asia.¹

To keep the book manageable it was necessary to impose some pretty strict boundaries. I opted to limit the focus to crops. These are the primary level of food production and account for most human food, either directly or indirectly as animal feed. Since the underlying justification of the book is to contribute to global food security, emphasis is given to those crops that provide most human calories (rice and wheat). They provide abundant examples of technology–policy interactions. Geographically, the book concentrates on areas where food insecurity is, or has been, particularly severe, populations are largest and agricultural is undergoing the most rapid transformation: Asia and Africa. North and South America, Europe and Australia, for example, have already transformed their agriculture and have relatively mature agricultural economies.

The book aims to assemble topic areas and examples from both the technological and policy sides to illustrate their interdependency. Topics are arranged in a natural hierarchy from the genetic resources through production systems to overarching global trade issues. There is no attempt to cover comprehensively the latest scientific advances. This would be impossible to cover in any one volume and anyway would be out of date by the time the book was published. However, authors were asked to write chapters that do report the latest in their fields and illustrate potential policy-relevant opportunities and bottlenecks. I also invited several leaders in their fields to take the readers on a ‘deep dive’ into some emblematic areas of particularly exciting scientific advances: genomics, photosynthesis, nutrition and remote sensing. These serve as anchors to real-world discussions of what policy–technological feedback systems are needed to meet global food needs in the coming decades.

I am certainly no historian, but I do have a weakness for history so I have tried to weave in a historical context whenever possible. To my publisher’s discomfort I also included footnotes that can lead students down what I think are some pretty interesting avenues of relevant inquiry that I could not figure out how to squeeze into the main text. I have also liberally sprinkled my various contributions with personal opinions. These are mine alone and do not reflect the opinions of the publisher or contributors.

I would like to thank those who helped make this book possible. First, my wife Crissan endured seemingly endless stretches of my mental absence as I tried to assemble a diverse set of contributions into some meaningful whole. I am indebted to my many friends and colleagues in the social sciences for patiently tutoring me in their respective fields over the years. The authors of course have been extremely generous with their time and knowledge and without exception cheerfully responded to my many inquiries and sometimes-heavy editing pen. Their only compensation for writing such excellent chapters is the knowledge that they are making a contribution to the broader community. Nicki Dennis and Lauren Webb from CSIRO held my hand through much of the process. While Nicki is responsible for convincing me to undertake this project, I alone am responsible for any errors that may have slipped through.

Endnote

1Zeigler RS (Ed.) (1996) Rice Research and Development Policy: A First Encounter . International Rice Research Institute, Manila. < http://books.irri.org/9712200841_content.pdf >.

List of contributors

Akinwumi A. Adesina

African Development Bank, Côte d’Ivoire

Vicki Abresch

University of Bonn, Germany

Kym Anderson

School of Economics, University of Adelaide, Australia

Arndt-Corden Department of Economics, Australian National University, Canberra, Australia

Gary Atlin

Bill & Melinda Gates Foundation, USA

P. Stephen Baenziger

Department of Agronomy and Horticulture, University of Nebraska-Lincoln, USA

Randolph Barker

Applied Economics and Management, Cornell University, USA

Howarth Bouis

International Food Policy Research Institute, Washington DC, USA

Paula Bramel

Global Crop Diversity Trust, Germany

Martin Brink

Centre for Genetic Resources, The Netherlands (CGN), Wageningen University & Research, The Netherlands

Steven Burgess

Departments of Crop Science and of Plant Biology, Carl R. Woese Institute of Genomic Biology, University of Illinois, USA

Isla Causton

Department of Biological Sciences, Oxford Brookes University, UK

Achim Dobermann

Rothamsted Research, UK

Tony Fischer

CSIRO Agriculture and Food, Australia

Bernd Friebe

Department of Plant Pathology, Wheat Genetics Resource Center, Kansas State ­University, USA

Robert T. Furbank

Research School of Biology, Australian National University, Canberra, Australia

ARC Centre of Excellence for Translational Photosynthesis,

Australian National University

CSIRO Agriculture and Food, Australia

Nicolas Gerber

University of Bonn, Germany

Bikram S Gill

Department of Plant Pathology, Wheat Genetics Resource Center, Kansas State ­University, USA

Allan Green

CSIRO Agriculture and Food, Australia

E. A. Heinrichs

IPM Innovation Lab, University of Nebraska–Lincoln, USA

Jikun Huang

China Center for Agricultural Policy, Peking University, China

Abdelbagi M. Ismail

International Rice Research Institute, Philippines

Dal-Hoe Koo

Department of Plant Pathology, Wheat Genetics Resource Center, Kansas State ­University, USA

Sarada Krishnan

Denver Botanic Gardens, USA

J. K. Ladha

International Rice Research Institute, Philippines

University of California, Davis, USA

Philip Larkin

CSIRO Agriculture and Food, Australia

Jan E. Leach

Department of Bioagricultural Sciences and Pest Management, Colorado State ­University, USA

Gilbert Levine

Biological and Environmental Engineering, Cornell University, USA

Wanlong Li

Department of Biology and Microbiology, Department of Agronomy, Horticulture and Plant Science, South Dakota State University, USA

Stephen P. Long

Departments of Crop Science and of Plant Biology, Carl R. Woese Institute of Genomic Biology, University of Illinois, USA

Lancaster Environment Centre, Lancaster University, UK

Department of Plant Sciences, Oxford University, UK

Jan Low

International Potato Center-SSA, CGIAR, Kenya

B. Minten

International Food Policy Institute, Ethiopia

Andy Nelson

Department of Natural Resources, ITC – Faculty of Geo-Information Science and Earth Observation, University of Twente, The Netherlands

Keijiro Otsuka

Kobe University, Japan

Alan Raybould

Syngenta Crop Protection AG, Switzerland

Thomas Reardon

Michigan State University, USA

University of Adelaide, Australia

P. M. Reddy

The Energy and Resources Institute, India Habitat Centre, India

H. Y. Shapiro

MARS Inc., USA

Rita Sharma

Ministry of Rural Development, Government of India

Indian Administrative Service (Retired), Lucknow, India

A. J. Simons

World Agroforestry (ICRAF), Kenya

Surinder Singh

CSIRO Agriculture and Food, Australia

Xavier R.R. Sirault

CSIRO Agriculture and Food, Australia

High Resolution Plant Phenomics Centre, CSIRO, Australia

Eric Stone

Research School of Biology, Australian National University

Research School of Finance, Actuarial Studies and Statistics,

Australian National University

CSIRO Agriculture and Food, Australia

David L. Topping

CSIRO Health and Biosecurity, Australia

Barbara Valent

Department of Plant Pathology, Kansas State University, USA

Theo van Hintum

Centre for Genetic Resources, The Netherlands (CGN), Wageningen University & Research, The Netherlands

Joachim von Braun

University of Bonn, Germany

Ross Welch

International Food Policy Research Institute, Washington DC, USA

Rod A. Wing

King Abdullah University of Science and Technology,

Biological and Environmental Sciences and Engineering Division, Saudi Arabia

Arizona Genomics Institute, University of Arizona

International Rice Research Institute, Philippines

Robert S. Zeigler

Portland, Oregon, USA

An introduction to the global food security, technology and policy nexus

Robert S. Zeigler

Food security as an emerging global concern is probably best dated from the founding of the Food and Agriculture Organization (FAO) of the United Nations in 1945. It is comforting that a sustained international effort to deal with one of the most pressing needs of all peoples of the world sprouted from the ashes of two world wars. It is reasonable that the vision of a world at peace would include a vision of a world where all people would be adequately nourished and in which agriculture – then the human activity that occupied more people than any other – would offer a fulfilling way of life.¹ However, it was clear that major increases in agricultural productivity were needed for sufficient food supplies to become a global reality. Famines were still a tragic part of human existence, with the Bengal famine of 1943 still a fresh memory.

There is no question that enormous challenges face us as we work to assure a sustainable and environmentally sound food supply for future generations. The FAO (2017a) Future of Food and Agriculture lays out these challenges and opportunities they present in an encyclopedic tapestry. Despite several years of encouraging decline, the number of undernourished people in the world ticked up to over 800 million. Nearly 25% of children show stunted growth (FAO 2017b). Human population is expected to grow to 10 billion by 2050 and food demand to increase by 50% (United Nations 2015a). As populations become increasingly urban, the type and quality of food in demand shifts. These changes, along with more sedentary lifestyle, present new challenges to agriculture: supply appropriate and healthy foods. The required future increase in food production matches that which was achieved in the unprecedented growth rates of the last half of the 20th century that themselves dwarfed the gains we have made throughout most of recorded human history. Now global food needs must be met while facing uncertain climate changes, political commitments to preserve Earth’s environment, dramatic shifts in where people live, how they make their living and ultimately their expectations for what makes a decent life. Because food security is essentially a quality of life issue, the technical considerations around crop productivity quickly become entangled with public policy and politics.

The impact of the interplay between technology and policies on global food security is so vast that major pruning is inevitable if any areas are to be treated adequately within the space limits of a book such as this. The constraints imposed by this prioritisation can be managed to some extent by examining broad and important thematic areas, such as biodiversity, crop improvement, human nutrition, government policies and trade; but for these treatments to be instructive, they must be placed within a real-world context. In this volume we take many of our examples from the major food staples, especially rice and wheat, in the major developing areas of the world, notably Asia and Africa, where most of the world’s remaining very poor and hungry people live.

Successes in global food security and second order problems

By the mid-20th century the glimmerings of a major revolution in agriculture were already visible. The Haber-Bosch process developed early in the century produced ammonia from the near limitless supplies of nitrogen in the atmosphere (Erisman et al. 2008). This ammonia became a source of inexpensive fertiliser that overcame one of the most serious limits to productivity in crop production: adequate nitrogen supply. Plant breeding, benefitting from early discoveries in genetics, was already producing much higher yielding hybrid crops, especially maize. Mechanisation was transforming agriculture in many parts of the world, replacing human and animal draft power with machinery fuelled by petroleum. And social movements were underway that would transform Asia and Africa from a colonial world ruled by European powers into one with many new nations.

In the 1960s stark differences in opinion emerged of how to tackle global food security. One school held that populations would inevitably outstrip global food supply, essentially expressing Thomas Malthus’ 18th century predictions² in terms of 20th century ecological ‘carrying capacity’ of the planet. This was popularised by books such as The Population Bomb by ecologist Paul Ehrlich (1968) that maintained that population growth was already outstripping agriculture’s capacity to supply enough food and that social and environmental catastrophes were unavoidable. Ehrlich argued that only some developing countries could hope to achieve food security with adequate investments in foreign aid, and merited support. Others, such as India and what would become Bangladesh, were beyond saving and should be left to fend for themselves. Rachael Carson’s A Silent Spring helped focus the attention of a nascent environmental movement on the negative aspects of the impact of agriculture on the environment (Carson 1962).

Philanthropic entities such as the Ford Foundation and the Rockefeller Foundation, on the other hand, were investing significantly in education and research in developing countries with the explicit intent to increase staple food supplies. While accepting that population growth could not continue indefinitely, major increases in food supply could forestall the inevitable global disruptions that massive famines would cause. Indeed, Rockefeller Foundation scientist Dr Norman Borlaug eloquently made the point in his 1970 Nobel Peace Prize acceptance speech (https://www.nobelprize.org/nobel_prizes/peace/laureates/1970/borlaug-acceptance.html) that increases in food supply would buy time while the world invested in developing the social and political structures that eventually would slow population growth. Building on their earlier work in agriculture and rural development these foundations created the International Rice Research Institute (IRRI, www.irri.org) in the Philippines and the Centro Internacional de Mejoramiento de Miaz y Trigo (CIMMYT – The International Maize and Wheat Improvement Center, www.cimmyt.org) in Mexico with the purpose of developing improved strains of rice, wheat and maize. These were the first of eventually over a dozen international agricultural research centres dedicated to improving agriculture in developing countries and supported by an informal group of donors called the Consultative Group for Agricultural Research, or CGIAR (www.CGIAR.org).³ The relatively modest investments in agricultural research were part of much larger investments by international lending agencies and official development assistance (ODA) in education, rural infrastructure and irrigation.

The dire predictions of mass famine did not materialise, while the investments in research to develop much more productive varieties of wheat and rice paid off handsomely. Having fed humans for millennia, most staples at the time did not appear to have great potential to increase their yields. If fertilised or grown in otherwise very favourable conditions, they tended to add more leaves and stems rather than grain. Scientists transformed these staples such that they responded to fertiliser and water by at least doubling their grain output. Other changes allowed much shorter growing seasons, meaning that with irrigation in tropical and subtropical regions two or even three crops could be grown per year, where previously only one crop was possible. The resulting dramatic increase in staple food production in developing countries became known as the ‘Green Revolution’.

By the late 1980s it was clear that famines – at least those caused by large-scale failure to produce enough food – had been averted. By the early 2000s, global food production had doubled, while cultivated land area increased by only ~10%. But the Green Revolution was not without its critics. Farmers often applied excessive amounts of fertiliser to their crops and changes in cropping patterns combined with susceptibility of the early modern varieties resulted in large pest outbreaks and excessive use of toxic pesticides as well. Large hydroelectric and irrigation schemes displaced rural populations and differentially favoured only a small proportion of the farming sector. Critics of the Green Revolution characterised it as favouring only well-off farmers and landholders. It was also described as a manifestation of Western capitalism that favoured multinational corporations. Indeed the ‘Green Revolution’ was coined as a counter to the ‘Red’ revolution that some in the West feared would sweep across the newly independent colonies. The investments in agricultural/rural development and food security were very much a part of the West’s Cold War portfolio.

The break up of the Soviet Union brought an end to the Cold War and with it a shift in ODA emphasis. China was embarking on an economic path compatible with Western interests. The fear of mass starvation was receding and the risk that social upheaval could lead to major changes in geopolitical and economic alignments seemed to fade. In the 1990s policy makers became aware of the science behind human activity-induced climate change. More broadly, global attention turned to the condition of the environment as exemplified by the 1992 Rio Earth Summit. In some quarters modern agriculture was seen as a major contributor to environmental degradation, especially in developing countries (IAASTD 2009; Robertson 2012). The adoption of new Sustainable Development Goals in 2015 (United Nations 2015b) has, however, recognised the critical role of sustainable agriculture in reaching development objectives while conserving our environment.⁴

Likewise, as the abundance of starchy staples removed the primary cause of starvation – inadequate supply of calories – second order problems appeared, such as inadequate supply of vitamins and minerals in the diets of the poor and nutrition-related problems such as diabetes and cardiovascular disease. This is the human nutrition manifestation of Liebig’s ‘Law of the Minimum’⁵ first articulated in plant nutrition: the growth potential of an organism is not determined by the overall availability of essential nutrients, but by that essential nutrient that is in shortest supply. Once that nutrient is in adequate supply, others take its place as the limiting factors.

This brief historical perspective touches on several themes that recur throughout this book. First is the importance of technological breakthroughs required for major gains in agricultural production and productivity. The impacts of technologies cannot be foreseen, unintended consequences are inevitable, and inherently these are neither good nor bad. Second, policies should be viewed not only as determinants of food availability or scarcity, but also as means through which technologies may realise their full impact. Third, there is a tension among policies, technologies, and social values and norms. It is useful to tease apart very briefly some examples that illustrate these themes. Let’s begin with nitrogen fertiliser.

Technological innovation

Nitrogen (N) is first among equals of major essential plant nutrients, along with phosphorus and potassium (Ladha et al. 2016). It is a part of almost all structures and processes in all living things. Although it is abundant in the atmosphere, most organisms are incapable of directly using the atmospheric form of N. All animals obtain all of their nitrogen ultimately from plants or microbes. To maintain or increase crop yields, N must be added to the soil in some way, because there is almost never enough innate supply from soil to meet basic plant needs. Some microbes can transform N from the atmosphere into biologically useful forms and this can be taken up by plants. These microbes my live symbiotically within plant roots, as in legumes, or as free-living organisms in close proximity to crops such as rice but under quite specific low-oxygen conditions. Most commonly, though, farmers add N to the soil as some form of fertiliser. Until recently this was from animal waste, crop residues or periodic flooding of fields that brought in fresh nutrients. By the late 19th century there was widespread concern that natural sources of nitrogen for fertilisers, primarily mineral nitrate and guano deposits, could not keep pace with demand. This fed into concerns about the impending ‘Malthusian trap’ where famine and misery were a direct result of the divergence between the arithmetic growth rate of agricultural production and the geometric rate of population growth. Demand for food by ever-growing populations would inevitably outstrip supply.

Such predictions depend on the sometimes not-so-explicit assumption that key aspects of the future will be pretty much the same as those in the past. Over almost all of human history this was a safe assumption. Transportation in 1500 BCE was not all that different from transportation in 1500 CE, and communication was dependent on transportation. Disease and health were pretty much a matter of Divine will. And almost everybody stayed close to home. However, what was not readily obvious in the 18th and 19th centuries, but is clear today, is that the rate of technological change appears to be following the same pattern of exponential growth as human population growth. With the benefit of hindsight this is not a big surprise. New ideas and innovations produce ‘offspring’ – ideas and technologies – that, given a favourable environment, produce new generations of ideas and technologies. Moore’s law describing the doubling of computing power roughly every 18 months is a well-known example of how feedback loops accelerate the rate of change.

The Haber–Bosch process used the newest technologies to generate enormous pressures, made possible by advances in metallurgy and catalytic chemistry, under which atmospheric nitrogen in the presence of methane (as natural gas or produced from coal) was converted into ammonia. This ammonia could be used directly as a fertiliser or used as a feedstock to produce a range of different nitrogen fertilisers. This led directly to abundant and inexpensive nitrogen fertilisers that have helped feed billions of people over the past century, thus at least postponing our Malthusian fate.

An interesting twist to the nitrogen fertiliser story is that a major impetus for creating ammonia was not only to produce fertilisers. Haber’s initial work was driven in part, if not wholly, to find a practical way to produce ammonia to meet Germany’s need for explosives for their munitions industry (Erisman et al. 2008). So, the process that led to eliminating famine for millions not only contributed to the deaths of untold millions via warfare, it was intended to be used to kill countless people. The benefit to humans may well have been an unintended consequence.

Policies, famines and technological revolutions

Most readers of this volume will be familiar with famines that led to the deaths of enormous numbers of people. Some of these were the result of a combination of gross mismanagement, genocide or outright cruelty, sometimes exacerbated by the weather or other environmental factors. These include those in the 1920s and 30s during collectivisation in Russia, the millions who died during Mao’s Great Leap Forward beginning in 1959, and the Biafra famine in West Africa in the late 1960s.

Those famines with putative natural causes include the Irish potato famine of the 1840s and the Bengal famine of 1943. Potatoes had become a staple for much of the European population after their introduction from the New World in the 1500s. Late blight of potato, a serious disease caused by the mould-like Phytophthora infestans, arrived in Europe in the mid 1840s. It devastated the potato crops across the continent, but the impact was particularly severe in Ireland where the peasant population depended almost exclusively on potatoes for their sustenance. But it was not simply the potato disease that caused the famine: the rest of Europe also suffered devastating losses to their potato crops but did not experience as severe a famine. An important difference was that England’s grain policies (the ‘Corn Laws’) imposed high tariffs on imported grain and artificially kept prices high so that even grain produced in Ireland was beyond the means of most of the rural population. Countless Irish perished in the midst of relative plenty.

The seizure of Burma from the British by Japan during World War II disrupted rice supplies for British troops and citizenry in Asia. Coincidentally, rice production in eastern India was reduced by a fungal disease. The resulting hoarding and redistribution of remaining rice supplies to British troops led to the starvation of millions in the Bengal region of India.

In both the cases of India and Ireland, while food production was severely reduced because of natural events, there were actually relatively abundant supplies of food available within reach of the populations. However, the governments had in place policies that mitigated against provision of the food to the starving populations. Outright gifts of food for famine relief were not considered appropriate for various reasons and the extremely poor rural people had no means to buy food.

Are all famines a result of policy failures? There certainly can be a case made for this in the modern world where deliveries of food to populations threatened with starvation can be made long before severe hunger sets in. There are now sophisticated early warning systems in place, global communications reach almost all regions where food shortages may occur, and the global community in general is more inclined to react swiftly to humanitarian crises. So, policies can also avert famine.

Entities such as the UN’s World Food Program, government ODA and many private charitable organisations respond quickly to food shortages before they can become famines. These organisations are able to operate with reasonable efficiency within policy frameworks across many nations that facilitate the flow of information and food in a timely manner. This in itself is a significant policy contribution to food security.

What of policy–technology interactions? Like technologies on their own, experience argues that policy innovations create their own feedback loops. Significant policy contributions to food security may be those that resulted in investments in technological advances, infrastructure and inputs. The growth in food supplies from the interactions of the different investments was probably many times the potential impact of any single investment. The high-yielding modern varieties of rice and wheat depended on adequate water and fertiliser to express their potential. Large investments were made in irrigation and rural infrastructure that brought reliable water supplies and fertiliser to farms and resulted in major production increases. Policies around water and fertiliser pricing were developed to promote their use with the express purpose of increasing food production. Rural roads connected newly productive lands to much larger markets. Government guaranteed prices assured farmers of a predictable income and consumers of affordable food. Investments in improving crop productivity via breeding and agricultural practices pay off when the crops are grown in optimal environments; investments in improving the crop growth and market environments pay off when crops have the genetic potential to respond to improved conditions.

Focus on crops, cereals, Asia and Africa

Three cereals – rice, wheat and maize – supply roughly 50% of human caloric intake. Within the major staple grains, most maize is raised for animal feed and is therefore mostly an indirect food source for people. Half of global wheat is produced in China and India, and it is the single most important source of protein. Almost all rice is consumed in developing countries (Awika 2011) and provides over 20% of human calories. If food security concerns should focus on developing countries and emerging economies – those areas with the most poverty and malnutrition – then wheat and rice can be very useful crops from which to draw specific examples.

A brutal, simplistic, but illustrative assessment of priorities could be: if the world fails to meet basic human needs in these major staple crops, any other success would be irrelevant because millions would starve. And, success in producing adequate supplies of the staple grains is a global victory for food security, even if there is failure in other aspects of agriculture. To some extent, this sums up the short-term accomplishments of the early Green Revolution. Starvation was averted and investments began to shift to other areas. But major investments are still required for proper nutrition, thriving populations and healthy environments. As the world undergoes major demographic changes from rural to urban, shifts in expectations from newly urban, wealthier and better-informed populations, and changing production potential of major food-producing regions, another major rework of agriculture is certainly called for. We are seeing not only major changes in how food is produced and by whom: the way food is marketed, who is buying increasingly internationally traded food, and how it is transported are having a growing important impact on what is grown and the kinds of food that are available and affordable to a very large proportion of our population.

If changes in global food security are measured as changes in numbers of hungry people and the ability of the poor to pay for enough food to meet their needs, then the most important places to track will be where the greatest concentrations of poor and recently poor live. Asia and Africa have over 5 billion of the world’s estimated over 7 billion people. Most of the world’s poor are also found in these regions. So any treatment of the impacts of technologies and policies on global food security should focus on these very high demand and potentially very high impact regions.

Food production, food security and climate change

There is little doubt within the scientific community that global climate is changing and that much of this change is the result of human activities. Burning of fossil fuels, agricultural and industrial processes and deforestation all contribute to increased greenhouse gas concentrations in the atmosphere. Decreases in biodiversity through habitat destruction and over-exploitation of natural resources may reduce the resiliency of natural systems to respond to the temperature and precipitation changes that are occurring. Sorting through the possible impact of climate change in particular regions is extremely difficult because the uncertainty in the various models blurs what the specific impacts will be and where they will occur. Regardless, major changes in distributions of rainfall and favourable temperatures are certain to occur. Today’s populations are still distributed based on legacy access to agricultural productivity of the past – not necessarily of the future. How the global community responds to climate change will certainly have an impact on the security, food and otherwise, of coming generations.

There is one major exception to the uncertainty surrounding the precise impact of climate change. And there is at least one obvious caveat that gives reason for some optimism. The exception is sea level rise. It is well established that global sea levels are already rising and all models predict this to continue throughout this century. The magnitude of the rise is uncertain, but that they will rise is not. This is important not only for the very large urban areas situated at current sea level, but also for the vast river deltas of Asia on which an enormous amount of the world’s rice is grown. Serious flooding and seawater intrusion will increasingly threaten the gains in production these regions experienced in recent decades. To a degree there are genetic means to adapt rice plants to flooding and salt water. The extent to which these biological solutions will be deployed and the feasibility of major supporting infrastructure investments, such as dikes, pumps and canals, remains unknown.

The methods and timeframe over which new crop varieties are developed drive the caveat that new crop varieties may take climate changes in their stride. High-quality varietal improvement programs breed crops in environments that mimic the intended growing environment. As temperatures, for example, change over decades the selection of new varieties of necessity takes place under the ‘new’ environments. The rate of climate change (many decades) is generally slower than the rate of varietal development (less than a decade). As our predictions of changing climate become more precise, breeding for adaptation to future environments is becoming feasible. A far better understanding of plant genetics and our ability to precisely manipulate breeding environments, as we will see, should allow plant breeders to develop high-performing crop varieties for the future climate. Globally this is good news. However, implicit in this view is that food production will shift to more favourable areas as climate shifts. For individual farmers and many countries this is not necessarily good news at all.

Much more complex, unfortunately, is what happens in the larger agroecology. The impact of temperature changes on the distribution and behaviour of pollinators, pests, pathogens and the broader ecology is still largely unknown.

Some foreshadowing

Recognising that many readers will not read every chapter, and without giving too much away, it should be helpful to highlight some of the key messages that will emerge from the overall coverage of this book. A quick read of the introductory remarks for each section will reinforce these messages.

It is already clear that the ultimate impacts of technologies and policies will depend on how they interact. Monitoring of their impacts by relevant scientific and political bodies can identify and reinforce positive feedback loops and squelch negative loops. What will be needed is for the decision makers in both areas to be aware of the relevant undertakings in the other to better inform their decisions. A challenge, of course, is agreeing on what is a good outcome.

Readers will see many examples of different and competing values and objectives. Is it inevitable that they be cast as ‘either/or’ alternatives? How are differing objectives weighed when a choice must be made? What is the value of the quality of a human life in comparison to, for example, the costs of preserving biodiversity? How should costs be distributed across societies, among countries, and between the public and private sectors? How should the distribution of benefits be determined?

A striking and recurring theme is unintended consequences. Opponents of the use of genetic engineering and ‘GMO’ crops cite unknown, unintended consequences as a justification for their caution. The unspoken and demonstrably false assumption is that these consequences will be overwhelmingly negative. What should be obvious to all, though, is that essentially every intervention, be it technology or policy, will trigger a cascade of results only some of which will be the explicit and intended ones. Making sense of how these results move through and impact communities, economies and ecologies is a major challenge. Ultimately the answers to questions of what is a ‘good’ outcome, for whom, and compared with what alternatives will be determined within a political environment.

Endnote

1The FAO traces its origins to the International Institute for Agriculture founded in 1905. A useful timeline may be found at: http://www.fao.org/about/en/ .

2See https://en.wikipedia.org/wiki/An_Essay_on_the_Principle_of_Population for a concise summary of Malthus’ landmark paper ‘Essay on the principle of population as it affects the future improvement of society’.

3For a summary of the first 40 years of the CGIAR see: https://cgspace.cgiar.org/bitstream/handle/10947/2761/cgiar40yrs_book_final_sept2012.pdf?sequence=1 .

4A very readable treatment of two contrasting views of mankind’s future in mid-20th century is captured in The Wizard and the Prophet: Two Remarkable Scientists and Their Dueling Visions to Shape Tomorrow’s World by Charles C. Mann (Knopf Publishing, New York, USA).

5See https://en.wikipedia.org/wiki/Liebig%27s_law_of_the_minimum for an entry into this fascinating part of agricultural history.

References

Awika J (2011) Major cereal grains production and use around the world. advances in cereal science: implications to food processing and health promotion. ACS Symposium Series 1089, 1–13. doi:10.1021/bk-2011-1089.ch001

Carson R (1962) Silent Spring. Houghton Mifflin, New York, USA.

Erisman J, Sutton M, Galloway J, Klimont Z, Winiwarter W (2008) How a century of ammonia synthesis changed the world. Nature Geoscience 1, 636–639. doi:10.1038/ngeo325

Ehrlich P (1968) The Population Bomb. Ballentine NY, USA.

FAO (2017a) The Future of Food and Agriculture: Trends and Challenges. Food and Agriculture Organization, Rome, Italy, <http://www.fao.org/3/a-i6583e.pdf>.

FAO (2017b) How Close Are We to Zero Hunger? The State of Food Security and Nutrition in the World 2017. Food and Agriculture Organization, Rome, Italy, <http://www.fao.org/state-of-food-security-nutrition/en/>.

IAASTD (2009) Agriculture at a Crossroads. Synthesis Report: International Assessment of Agricultural Knowledge, Science and Technology for Development (IAASTD). Island Press, Washington DC, USA.

Ladha JK, Tirol-Padre A, Reddy CK, Cassman KG, Verma S, Powlson DS, et al. (2016) Global nitrogen budgets in cereals: A 50-year assessment for maize, rice, and wheat production systems. Scientific Reports 6, 19355. doi:10.1038/srep19355

Robertson T (2012) The Malthusian Moment: Global Population Growth and the Birth of American Environmentalism. Rutgers University Press, New Brunswick NJ, USA.

United Nations (2015a) World Population Prospects: the 2015 Revision. United Nations, New York, USA, .

United Nations (2015b) Transforming Our World: The 2030 Agenda for Sustainable Development. UN General Assembly A/RES/70/1. United Nations, New York, USA, <www.un.org/ga/search/view_doc.asp?symbol=A/ RES/70/1&Lang=En>.

PART 1

TAPPING AND CREATING GENETIC RESOURCES

The foundations of our global food supply are built from the crop species our ancestors domesticated millennia ago. Plant breeders today aim to systematically understand and use the genetic diversity available in our crops to further adapt them to a wider range of environments and a changing climate, as well as to improve their yields, productivity, nutritional value and expand their uses beyond simple food. This flows from the largely unconscious acts by early farmers to select those materials from their fields that best suited their needs, but relying only on obvious performance characteristics and with no knowledge of genetics. Both ancient farmers and modern plant breeders required a diverse population from which to select and create new varieties of crops. It was not until a little more than a century ago when Russian botanist Nikolai Vavilov systematically began collecting representatives of major crop species that the diversity of crops was appreciated, catalogued and then made available to breeders to develop new crop varieties.

Today there are many national and international collections of most of our crops, albeit of widely varying coverage and sophistication. These ‘gene banks’, or ex situ collections, typically contain true seed, but for some crops only vegetative materials can be preserved. The first two chapters of this section summarise the complexities of establishing, maintaining and using these collections. Chapter 1 summarises the status of global collections and the massive data management challenges that confront collection curators as the information available for each accession grows exponentially with advances in our genetic technologies. Seed and other propagule collections help preserve what has been achieved by farmers and breeders in the past. Preservation of the original crop habitats – in situ conservation – is described as a means to maintain the process that gave rise to our current crop-based food systems.

Chapter 2 takes the reader on a deep dive into the exquisite diversity of some of our most important crops: bread wheat and it allies. Domestication of a wild species for human purposes necessarily involves the elimination of many traits that are of little use, or are actually detrimental, to human needs. Many potentially beneficial traits were lost along the way as well. The heretofore intractable complexities created by the multi-species hybridisations that eventually yielded today’s wheat are now amenable to manipulation by wheat breeders and molecular biologists.

Chapter 3 guides the reader through the history and daunting complexity of the international community’s effort to monitor and manage use of genetic resources. Of particular interest are the attempts via international agreements to assure that monetary benefits flow to segments of society historically excluded from these. The thorough examination of the ramifications of these well-intentioned efforts on today’s flow of genetic resources is a sobering reminder of the impact of unintended consequences.

The challenges of converting collections of genetic resources from essentially museums of genetic diversity to active collections that are well characterised from the genetic to field level are not to be underestimated. Using rice as an example, Chapter 4 presents readers a clear view of how the latest tools in genomics allow us to appreciate in fine detail the relationships among rice and its many wild relatives. This appreciation allows far more precise selection of candidates – both rice and its relatives – for in depth study and ultimate use by breeders.

The myriad of treaties, agreements, protocols and conventions were created to establish a semblance of order in our treatment of genetic resources. Yet there remains a set of overarching questions around how the global community manages them: Who will have access to these resources? Who will benefit from them? Who will profit from them? And who will preserve them for our descendants? Finally, what are the implications of the major philosophical shift from treating genetic resources as a ‘heritage of all mankind’ to being treated as a sovereign natural resource? Although not providing simple answers to these questions, each chapter offers the reader insights into the varying perspectives of different stakeholders as well as helping the reader to unravel the complexities that attempts to answer these questions reveal.

1

Systematic assessment for conservation and utilisation of crop genetic resources

Paula Bramel and Sarada Krishnan

Introduction

Global food systems are facing significant future challenges to meet the growing demand for nutritious food for nearly 9 billion people. This need for an increased supply must be met while facing numerous challenges for agricultural production systems including: temperature and precipitation changes resulting from climate change and the associated increased biotic and abiotic stresses; the need to redress environmental degradation; increased urbanisation with its impacts on land and water use, changing consumer food preferences, and rural population levels; and the competition for land use for non-food crops and other non-agricultural uses. The inescapable conclusion is that there is a need to continue to increase productivity, production, resilience and quality of crops on remaining agricultural land. In several developing countries there is also a policy objective to ensure decent livelihoods for smallholder producers and others in the value chain (see Chapter 23). A key set of resources for crop improvement is genetic resources conserved as propagules (seed or other plant organs used for reproduction) ex situ in institutional gene banks and in situ in farmer’s fields or in protected sites.

Gepts (2006) reviewed the history and three key accomplishments in the field of plant genetic resource conservation. The first and second accomplishments related to an increased awareness of the benefit of genetic resources as well as the significant risk of loss of this genetic diversity from genetic erosion. This resulted in different method being deployed to conserved and make available at-risk varietal diversity from farmers’ fields and in natural areas. The third major accomplishment has been the development of methods to characterise genetic diversity and make the management of conservation more efficient and secure. Currently there are more than 7.5 million propagule samples, or accessions, conserved in 1750 gene banks (FAO 2010). Five international gene banks and 72 national institutions hold 91% of the total global accessions of 18 major and minor legume crops (Bramel and Upadhyaya 2018). The number of accessions and the number of crops held in the largest collections of minor and major grain legume crops is given in Table 1.1. These 10 collections account for ~45% of all the accessions held globally. For wheat, 44 institutions hold 70% of global wheat accessions (Bramel 2017). Thus, globally, a high percentage of accessions are held by a small number of large collections for the many crops of global significance.

Table 1.1.   The number of accessions and the number of crops held in the 10 largest collections of 18 major and minor grain legume crops.

Source: FAO (2010).

The complexity and expense of managing these large collections offers challenges both to those who curate them and to users. Maintaining the integrity and viability of seed for an ex situ collection over many decades requires large investments in reliable cold stores, monitoring seed viability and maintaining genetic integrity while multiplying accessions for rejuvenation or subsequent distribution to users. The challenges are even greater for crop species that are propagated by vegetative means (e.g. stem cuttings, roots and tubers). Many collections have limited accession level data available to facilitate use, some have a high degree of duplications with other gene banks, and many are not securely conserved or even used. So although ex situ conservation was an approach to ‘secure’ the genetic resources from the threat of loss and increase the availability of these resources to users, it faces a range of new threats to genetic integrity in conservation that also complicates selection of accessions for evaluation and use.

Use of genetic diversity conserved in ex situ collections will be very important in the future because this represents a primary resource for crop breeders developing new varieties to meet future food challenges. Most users of the conserved accessions are looking for only a small number of accessions that will have a positive impact on allelic diversity for traits of interest with minimal introduction of undesirable traits or alleles. One assumption of ex situ conservation is that these collections will be available for evaluation and use because they are more readily accessed compared with in situ conservation in farmers’ fields or in protected areas. The goal of gene banks is to offer secure, efficient and cost-effective operations for preservation, while being accessible to users. The management costs and difficulties grow rapidly with the size and complexity of a collection. The challenge is to maintain availability of accessions for use by researchers, crop breeders and farmers.

The genetic diversity conserved in ex situ collections is a sample of the allelic diversity in a population at the specific time of harvest. All effort should be made during the collection to adequately sample the diversity from the farmer’s field, or the grain store or from a wild population, but this is not always possible. In farmer’s field or in natural areas, the original variety or population will continue to face selection pressures that is part of the dynamic nature of population level allelic diversity. Thus, the continued conservation of the original variety or population in situ will allow for resampling to capture these positive changes in allelic composition, especially in relation to adaptation to biotic or abiotic stresses, or to recover lost accession from ex situ collections. FAO (2016) reported that more than 2000 species were being conserved in situ but this was much lower than what was needed. Conservation of genetic resources in situ presents a daunting array of logistical challenges: identification of populations in need of preservation; procurement and long-term acquisition of dedicated land; education, buy-in and compensation for farmers engaged in in situ conservation; and contingency plans for loss or damage from natural or man-made disasters, to name a few.

Assessments of diversity are important for determining how to manage ex situ collections as well as for the identification of sites with high genetic diversity for protection or in situ conservation. Tools for assessing genetic diversity also have a role in describing the site level distribution of diversity that can be used to develop conservation and monitoring plans. This chapter reviews the current status and impact of diversity assessment on conservation and use of genetic resources to meet future environmental and agricultural challenges.

Genetic diversity assessment: basic principles and tools

Genetic variance is a product of the number of loci segregating in the population, the difference in gene frequency at individual alleles and the gene action. Genetic diversity (heterozygosity or heterogeneity) can be a characteristic of an individual, a population, species and genus. Diversity assessment can be used to enhance the conservation and utilisation of genetic resources. There have been many applications of these assessments, mainly based on morphological or other phenotypic measures, but increasingly these are being based on DNA sequence-based genomic estimates of allelic diversity. A systematic assessment of genetic diversity focuses on two measures: the richness or degree of diversity, the evenness or distribution of the diversity, or both. Individually each measure has its limitation and thus a combined index, such as the Shannon-Weaver Diversity Index is often used (Brown and Brubaker 2002).

To make gains in the multiple traits involved in productivity, stability and quality, it will be necessary to take advantage of the allelic diversity conserved in ex situ collections. This diversity is a product of the past selection from natural processes and, for crops, by farmers for adaptation. For example, Westengen et al. (2014) explored the diversity within sorghum grown in Africa. They hypothesised that understanding social, cultural and environmental factors in the structuring of genetic diversity among local sorghum landraces would quantify the resilience of local food system to the impact of climate change. They concluded that ethno-linguistic groups (social and cultural sources of diversity) were the main determinates of structure among the sorghum landraces, while all other factors (geographical distance, ecology and morphological traits) were of significance only within the ethno-linguistic groups.

Having greater information available on accessions held in gene banks is a prerequisite for the efficient conservation and utilisation of the genetic diversity. For example, Singh et al. (2014) systematically evaluated environmental, phenotypic characteristics and trait diversity among a large collection of wild lentil (Lens sp.). They used these diversity analyses to identify accessions as sources of useful traits to be used in breeding programs, and to identify sites for future collection and protection.

When an accession is collected or acquired by a gene bank, there is a need to document basic information on the origin, location where collected, and other relevant data on the history or use from the donor of the germplasm. There are internationally agreed standards for passport data that is to be made available on accessions in collections (Alercia et al. 2015). Phenotypic characterisation of the accessions can be done using morphological, physiological or agronomic traits. The traits need to be highly heritable and thus repeatable. For many crops, there are internationally agreed standard descriptor list for characterisation of traits (FAO 2014; Bioversity International 2017). In most cases, these data are taken over years and locations with minimal replication. The use of data standards for passport and characterisation data has allowed for the global sharing of accession level data in platforms such as Genesys (Genesys 2017).

Allelic or gene level diversity is not always evident in the phenotype, especially when characterised or evaluated in the environment outside of those where they originated. This is particularly a challenge for the wild relatives of crops where the value is not very predictable based on per se performance given the influence of a high proportion of undesirable genes in the background of the accessions (Tanksley and McCouch 1997). One alternative is to use DNA level measures of genotypic diversity. Spooner et al. (2005) reported on a comprehensive review of the DNA level marker technologies available for use in assessing diversity. They reviewed the application, the comparative advantages and their limitation for use of the various technologies in assessing allelic level diversity. In an effort to standardise documentation of information about molecular markers, De Vincente et al. (2004) proposed a list of descriptors for genetic markers technologies. The aim was to generate replicable and standardised genetic marker data that could be used by researchers using these technologies.

The use of genomics to predict the genotypic value of an accession is considered a powerful new tool to improve the conservation of gene bank accessions and to predict the value of individual accessions to crop improvement (McCouch et al. 2012). Molecular characterisation is useful in: assessing the genetic diversity of collections; conducting detailed population genetics studies to provide an understanding of evolutionary and domestication history of crops; eliminating mislabelling of collections; and reducing redundancy of accessions leading to reduction in maintenance costs (McCouch et al. 2012; Guiltinan and Maximova 2015; Table 1.2). Increasingly, sequence-based assays such as genotyping-by-sequencing (GBS) are being employed for germplasm evaluation (McCouch et al. 2012; FAO 2014).

Table 1.2.   Molecular marker technologies and their applications.

Enhanced use of ex situ collections

A systematic assessment of the structure of a collection is an approach to dissect the dimensions of phenotypic or genotypic variation into cluster or groups of accessions with greater similarity within the group and greater distance between groups. This grouping will allow for a greater understanding of the degree (richness) and distribution (evenness) of the phenotypic diversity or genotypic diversity, as well as identify adaptation complexes for differential environmental conditions among accessions in collections. It will also allow for sampling of this diversity for users in core collection, mini-cores or core reference sets (van Hintum et al. 2000; Glaszmann et al. 2010; Upadhyaya 2015; Upadhyaya et al. 2011). These subsets maintain the original diversity of the collection but in a size that facilitates the evaluation, use, and conservation of the collection. These core subsets have a known relationship back to the original collections so resampling the groups of greatest interest or further sub-division is possible to identify further accessions for testing. There are various approaches to sample accession within groups to maximise the sampling to meet the needs