Wheat improvement: food security in a changing climate

For more than 10,000 years, wheat has been the cornerstone of food and nutritional security and is currently the most widely grown crop in the world. Due to its unique processing and quality characteristics, and since it can be easily transported and stored – it is also the world’s most traded crop and often the frst choice when food aid is needed for famine-struck regions. Grown on all fve continents and in more diverse environments than any other crop, wheat is vulnerable to a wide range of transboundary diseases and abiotic stresses, particularly heat and drought. Resistance to these stresses plays an important role in efforts to breed for yield stability, the most-requested trait among wheat farmers across the globe. Half a century ago, wheat was also one of the most-studied crops. But for reasons related to its biology – wheat is self-pollinated, and thus its seed can be readily saved and shared for the next crop – it has not attracted the same private sector investment in breeding research as crops with a higher fnancial return on investment, for example hybrid and genetically modifed (GMO) crops. Consequently, the public sector remains the largest provider of improved wheat varieties. This is particularly true in the Global South where more than 1.5 billon resource-poor people are dependent on a constant and affordable supply of wheat as a staple food. Globally, the crop provides about 20% of all human dietary protein and calories. Climate change and consequential periods of extreme heat, cold and drought, combined with disease threats, represent huge challenges. A 2 °C temperature increase will reduce wheat yields in the Global South by 10–15%. At the same time, average yields will need to go up 40% by 2050 to provide enough food for a still growing population. Provision of suffcient calories and protein remains essential. Estimates from 2020 show that around 820 million people still go to bed hungry each night, only a slight decrease from the 2000 estimate of 900 million, indicating that we are unlikely to reach the UN goal to end hunger by 2030. Furthermore, in addition to calories, other nutritional aspects of diets must be assured, especially for consumers whose dietary options are restricted. Wheat scores well here too, being an important source of dietary fbre, minerals, B vitamins and other micronutrients, as well as an outstanding source of plant protein. Contrary to the 'food-fad' misinformation emanating from the Global North, there is no evidence that intensive breeding has decreased the nutritional quality of wheat, nor that wheat proteins trigger adverse responses in the vast majority of people. This book covers all aspects of wheat improvement, from utilizing genetic resources to breeding and selection methods, data analysis, biotic and abiotic stress tolerance, yield potential, genomics, quality nutrition and processing, physiological pre-breeding, and seed production. It dedicates a fnal part to rapidly evolving technologies and their potential to accelerate genetic gains and adaptation. This is the frst book in many years focusing on wheat science in such a wide and comprehensive way. I commend the editors and Springer for bringing out this important publication now. While this textbook focuses on wheat per se, its 32 chapters, written by leaders in their disciplinary felds, address cutting-edge issues relevant to many other crops. Considering the remarkable progress made in genetics, molecular breeding, phenomics at breeding scale and bioinformatics, I am sure that this book will be immensely useful to students – the future wheat science leaders – and that it will help scientists, plant breeders, extensionists, agro- ndustrialists, farmers and policy developers better understand how wheat can remain a pillar for sustainable global food and nutrition security.

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