Wheat. Peter R. Shewry

      Source: Data from Monfreda et al. (2008). Mapping modified from Andrew MT, CC BY‐SA 3.0, https://commons.wikimedia.org/w/index.php?curid=9643590

      1.1.2 Wheat Supply and Demand

As stated previously, there have been significant pressures to invest in and therefore further increase the dominance of the major cereals. There is undoubtedly a trade‐off between increasing the efficiency of production through specialization and increasing the resilience of systems through exploiting diversity (Urruty et al. 2016; Dardonville et al. 2020). Nonetheless, investment and focus on wheat have enabled production to be increased by more than threefold over the past 60 years (Figure 1.4). Indeed, the rate of growth has significantly exceeded that of the number of humans on the planet, and has met further demands arising from changing eating habits. Of note is the increase in the per capita availability of wheat between 1960 and 1990 in populous countries such as India and China, despite rapid population growth during the same period (Figure 1.3). Furthermore, the increase in global wheat production since 1960 occurred without using more land (unlike rice, maize, and soybean). Global production of wheat, therefore, closely follows the increases in yield per unit area (Figure 1.4). In other words, we have become much more efficient in the use of land for wheat production (Dibb 2000). There are clear threats to being able to sustain or increase land‐use efficiency to produce wheat, but these challenges need to be set against the environmental impacts of using more land or the difficulties of achieving significant changes to human diets (e.g. Smith et al. 2018; Cassman and Grassini 2020). It is salutary to reflect that many past civilisations have failed to meet the challenge of satisfying short‐term demands for food, without severely impairing the ability of future generations to do likewise (Hillel 1991; Montgomery 2007; Mithen 2012). However, given current trends in population growth and diet, which also drive increased use of grain for livestock production, it is predicted that demand for grain could increase by around 50% between 2020 and 2050. It is highly unlikely that new crops and/or novel cropping systems will be able to provide the intensification of production that will be required to meet this increased demand. This argument will hold even if the increase in demand is limited to 25% by dramatic changes to the relationships between income, urbanization, and diet seen over recent decades (Cassman and Grassini 2020). There is, therefore, continuing pressure to increase the efficiency with which we use land to produce wheat and other grains.

Figure 1.3 Changes in the availability of wheat (kcal/capita/day) in the diets of nine countries.

      Source: Data from FAOSTAT (FAO 2021).

Despite the past success in increasing grain production (Figure 1.4), the last 30 years have seen food price spikes (Figure 1.5) associated with perturbations in the supply and demand for wheat. These shocks have resulted from many factors, including extreme weather events in major wheat‐growing areas, changes in land‐use policy (particularly regarding biofuel production) affecting the area of food grains, the oil price, the behaviour of financial markets, and the buying and selling strategies of major wheat exporters and importers seeking to secure domestic supplies (Tadesse et al. 2016). The most dramatic spike in recent decades was in 2008; this represented a fourfold increase in the wheat price compared to that of eight years earlier (Figure 1.5). The origins of this spike have been attributed to drought, crop disease, grain use for biofuels (and therefore the oil price), and increasing demand resulting from the economic growth of China and India. Wheat price spikes result in increased poverty and have a disproportionately harmful effect on the livelihoods and well‐being of the poor (Anderson et al. 2013).

Table 1.1 Production, yield, and area of wheat in the world and selected regions and countries.

      Source: Data are means of 2016 to 2018, from FAOSTAT (FAO 2021).

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Region/Country	Production (106 t)	Yield (t/ha)	Area (106 ha)
World	752	3.5	217.3
Regions
Asia	331	3.3	99.3
Europe	256	4.1	62.7
Americas	114	3.3	34.7
Africa	26	2.6	10.1
Australia/NZ	25	2.2	11.5
Top 10 countries
China	133	5.4	24.5
India	97	3.2	30.3
Russian Federation	77	2.9	27.1
USA	54	3.3	16.3
France	35	6.5	5.4
Canada	31	3.3	9.3
Pakistan	26	2.9	9.0
Ukraine	26	4.0	6.4
Australia	25	2.3	11.5
Germany	23	7.3	3.2