Wheat

Wheat is one of the most important cereal crops in the world, providing food for billions of people. It is a highly adaptable crop and can be grown in a variety of climates and soil types.

The wheat plant is an annual grass that can grow up to four feet tall, with a single stem and narrow leaves. It has outer layers, known as bran and germ, which are normally removed from wheat grains after harvesting, leaving the starchy endosperm behind. After its grinding into flour, this is used to create a range of foods, such as bread, pasta, pizza, and pastries.

The wheat plant requires well-drained, fertile soil and needs a modest amount of rainfall. To boost crop productivity and defend against disease and pests, most conventional farmers utilize fertilizers and pesticides. The wheat plant is typically sown in the fall and harvested in the summer, however, the precise date might change depending on the variety and climate.

Both for human consumption and as animal feed, wheat is a significant crop. It is also a valuable commodity in global trade, with significant exporting countries including the United States, Canada, and Australia.

Five impressive facts about wheat

1. Wheat is one of the oldest crops in the world. It has been cultivated for more than 10,000 years, beginning in the Fertile Crescent also known as the “cradle of civilization”. Its area, among the Tigris, Euphrates, and Nile rivers, covers what are now southern Iraq, Syria, Lebanon, Jordan, Palestine, Israel, Egypt, and parts of Turkey and Iran
2. Wheat was introduced to America by the early English colonists and it quickly became the main cash crop of farmers. Wheat was the main crop cultivated by the Middle Colonies (New Jersey, New York, Pennsylvania, and Delaware) which became known as the “breadbasket” colonies
3. More than 600 pasta shapes are produced worldwide
4. Spring-planted wheat usually takes 120 days from seeding to harvesting but it depends on variety, altitude, and weather conditions
5. In addition to being high in carbs, wheat has a central place in human nutrition providing components that are essential or beneficial for health and notably protein, B vitamins, dietary fiber, and phytochemicals. Wheat also contains a protein called gluten which can trigger a severe autoimmune response (called celiac disease) or other unpleasant symptoms in predisposed individuals

Wheat growth stages

The wheat plant undergoes three developmental stages as it grows from seed to harvest.

The first stage begins immediately when the seeds begin to germinate and stops at the onset of stem extension. During this period, the canopy grows, and yield-bearing shoots, tillers, and basic roots form. The environment will determine the rate of growth at this phase.

The second phase begins with the first node being visible and lasts until flowering. In this phase, deep roots, fertile florets, yield-delivering leaves, and stem reserves develop. Growth is also very rapid, with a high daily nutrient demand from the soil.

The third stage, also known as the production stage, starts immediately after flowering and lasts until the grains are full and ripe. The amount and weight of grain are determined during this period.

Global demand and market value of wheat

The global demand for wheat is driven primarily by its use as a staple food for human consumption. Wheat is a key ingredient in a wide range of foods, and as a result, the demand for wheat is closely tied to population growth and changes in dietary preferences.

The global wheat market reached a consumption value of around $153.2 billion in 2022. The largest consumers of wheat are China, the European Union, and India, which together account for around 40% of global wheat consumption.

In addition to its use in human food products, wheat is also an important feed grain for livestock, particularly poultry, and pigs. As global demand for meat and dairy products continues to rise, so too does the demand for wheat as animal feed.

The global demand for wheat is expected to continue to grow in the coming years, driven by population growth, changing dietary habits, and economic development in emerging markets. However, climate change, water scarcity, and other environmental factors affect the sustainability of wheat production and supply globally.

Global production of wheat and the impact of the Russia-Ukraine conflict

China, India, Russia, and the United States are the four largest individual wheat producers in the world, accounting for about half of the world’s total wheat production.

China is the world’s largest wheat producer producing more than 2.4 billion tonnes in the last 20 years, around 17% of total production, while Russia is the largest global wheat exporter, exporting volumes worth more than $7.3 billion in 2021.

The global production of wheat varies from year to year due to factors such as weather, pests and diseases, and market conditions. 

It is also worth noting that certain events such as the COVID-19 pandemic and the Russia-Ukraine war affected the global production of wheat. In 2019, Russia and Ukraine together exported more than a quarter of the world’s wheat. As a result of Ukraine’s production capacity being affected by Russia’s military invasion in 2022, and many nations restricting or ending trade links with Russia, global wheat prices skyrocketed.

Global wheat prices increased by over 60% over the period from February 24 to June 1, 2022, compared to the average in January 2022, creating catastrophic food shortages in a large number of countries in the Global South. For example, the Russia-Ukraine war further deteriorated food security in Yemen, a country in an armed conflict since 2015 and one of the largest humanitarian crises in the world. Wheat is a key staple in Yemenis’ diet. Yemen’s cereal import dependence ratio is 97%, with Russia and Ukraine accounting for the largest share of wheat imports (more than 40%). 

Thanks to the “grain deal”, Ukraine has been able to transport millions of tonnes of food through the Black Sea despite the ongoing conflict. Wheat prices started falling, returning to pre-war levels. Nevertheless, since the war may be worsening (there is no end in sight) and Russia threatens to scrap the grain deal, the effects on wheat prices and food security may come back even stronger.

Is climate change affecting the production of wheat?

Rising temperatures and an elevated atmospheric CO2 concentration highly affect wheat production and crop quality. Higher temperatures:

• affect the length of growing seasons and accelerate crop maturity
• cause a high rate of transpiration, which causes drought that ultimately leads to low productivity

Higher levels of CO2 in the atmosphere have a positive effect on photosynthesis and water retention, increasing crop yields. However, those increases come at the cost of lower nutritional quality as plants accumulate more carbohydrates and less minerals (notably iron and zinc), which can negatively affect human nutrition. This increase in CO2 also decreases the grain protein concentration of wheat crops, which poses a serious health risk for a large portion of the population who rely on wheat as their main source of protein.

A study published in Science Advances analyzed simulations from 27 climate models. Results indicate that unless immediate mitigation steps are taken, global warming could cause major droughts in 60% of wheat-growing areas around the world (current droughts affect 15% of wheat production). Even if the Paris Agreement’s target of stabilizing temperatures at 2°C above pre-industrial levels is met, severe water scarcity would still double in the next 20 to 50 years.

The study also points out that the trend of droughts leading to increased food prices is likely to continue. As a consequence, low-income regions of Africa and Eastern and Southeastern Asia will be the worst-affected regions since it is also where malnutrition rates are higher and where food systems highly depend on wheat. 

Also, excessive rainfall and flooding can have a negative impact on wheat production, as waterlogged soils can lead to reduced root growth and increased risk of diseases.

Wheat is susceptible to a variety of pests and diseases, including rusts, aphids, and Hessian fly. These can cause significant damage to wheat crops and reduce yields.

Continuous wheat cropping and improper land management can lead to soil degradation, which can reduce soil fertility, increase erosion, and decrease crop yields. It is therefore important to adopt sustainable land management practices such as regenerative agriculture.

In order to mitigate these risks, new wheat varieties that are more resilient to pests, diseases, and environmental stresses are being developed. In addition, regenerative farming practices, such as conservation tillage and crop rotation, can help to improve soil health and reduce the risk of soil degradation.

Requirements for wheat production

Here are some of the key requirements for successful wheat production:

• Climate: Wheat can be grown in a wide range of climatic conditions, but it generally prefers cooler temperatures and moderate rainfall. Wheat can germinate in soil temperatures from 4C to 37C, but temperatures from 12C to 25C are considered optimal

• Soil: Wheat can grow in a variety of soil types, but it generally prefers well-drained, fertile soils with a neutral pH. The soil should be free of weeds and plant debris, which can compete with wheat for nutrients and water

• Seed quality: High-quality seed is essential for successful wheat production. The seed should be free of diseases and pests and should be planted at the optimal time and depth to ensure good germination and establishment

• Nutrient availability: Wheat requires certain nutrients, such as nitrogen, phosphorus, and potassium, to grow and produce a healthy yield. Organic fertilizers can help to provide these nutrients and improve soil fertility when applied

• Pest and disease management: Wheat is susceptible to a variety of pests and diseases, which can cause significant damage and reduce yields. Effective pest and disease management strategies, such as crop rotation, use of resistant varieties, and timely application of pest control measures, can help to minimize these risks

• Harvest and post-harvest management: Harvesting wheat at the optimal time and using appropriate equipment and techniques can help to maximize yield and grain quality. Proper post-harvest management, such as drying and storage, can help to preserve the grain and maintain its value

Cultivating wheat using regenerative agriculture methods

The use of regenerative agricultural practices can be applied to the cultivation of wheat and has the potential to increase yields, reduce soil erosion, increase soil organic matter, and improve the nutritional value of wheat.

Regenerative agriculture can be applied to cultivating wheat in the following ways:

• Crop rotation: Wheat can be rotated with other crops, such as legumes or cover crops, to enhance soil health and reduce disease and pest attacks. Legumes, like clover or peas, can fix atmospheric nitrogen, which can be used by subsequent crops, such as wheat. Cover crops, like rye or vetch, can protect the soil from erosion, suppress weeds, and add organic matter to the soil

• Reduced tillage: Tillage can damage soil structure, increase erosion, and reduce soil organic matter. Reduced tillage or no-till farming practices can improve soil health, enhance soil water-holding capacity, and reduce greenhouse gas emissions

• Organic or biological pest management: Rather than using synthetic pesticides, farmers can use natural pest management techniques to manage insect and disease pressure. Examples include crop diversification, intercropping, and the use of predator insects and microbial-based pesticides

• Agroforestry: Agroforestry with wheat involves the cultivation of wheat within a forest or agroforestry system, which can provide many benefits to the soil, environment, and farmers
  
• Mixed seeding combinations of wheat, flowers, and beans, and/or peas

Here are some ways agroforestry can be practiced with wheat:

• Alley cropping: In alley cropping, wheat is grown in between rows of trees or other woody plants. The trees provide shade, which can help to reduce soil erosion and retain moisture, while also providing a source of income from the sale of timber or fruit.

• Windbreaks: In windbreaks, trees are planted in a line or a staggered pattern around the edge of the field to protect the wheat from wind erosion and to reduce wind damage. The trees also provide a habitat for wildlife and can help to sequester carbon from the atmosphere.

• Silvopasture: In silvopasture, wheat is grown as a cover crop between rows of trees or other woody plants that are grazed by livestock. The wheat provides a source of forage for the animals, while the trees provide shade and shelter.

Overall, agroforestry with wheat can provide many benefits to farmers, the environment, and local communities. By integrating trees and woody plants into wheat production, farmers can increase their income, reduce their reliance on external inputs, and build more resilient and sustainable farming systems.

Can wheat increase grain yield in shade?

Most cereal species, such as wheat, have been selected for full light conditions and it is unclear how shade affects production. In order to determine if wheat is a crop with potential for use in agroforestry systems, an experiment conducted in central Spain proved that wheat had a 19% higher grain yield at both 90% and 50% irradiance levels compared to full light. 

This reveals that wheat is suitable for growing under a partial tree shade in high-radiance climates, highlighting the utility of agroforestry practices that could mitigate grain yield decreases caused by climate change.

A study conducted in China was focused on the competition between wheat and trees. Three different fruit tree/wheat (jujube/wheat, apricot/wheat, and walnut/wheat) intercropping agroforestry systems were chosen to investigate the influence of different fruit tree shade intensities on the growth, yield, and quality of intercropping wheat. results show that jujube-based intercropping systems offer a suitable agroforestry system in the region since they did not decrease the yield and quality of the intercropped wheat. daily shade intensity was positively linearly correlated with wheat grain protein content, wet gluten content, and dough development and stability times.

Different wheat varieties for different biomes

In order to address the challenges caused by climate change, wheat breeders have been developing new wheat varieties that are climate-adaptive. Scientists have discovered new alternative dwarfing genes that allow wheat seeds to draw moisture stored twice as deep from the soil as present cultivars.

According to Dr. Greg Rebetzke, an Australian scientist, “We have genetics that can allow us to sow earlier and deeper up to 120 millimeters while keeping the plants short and allowing for very long coleoptile, which is the shoot that grows from the seed to the soil surface.” He further added that “A coleoptile is like a drinking straw that can push through dry and hard soil, allowing the germinating wheat leaves to emerge above the ground.”

Also, a new variety known as the durum wheat variety has been developed by scientists from the International Center for Agricultural Research in the Dry Areas (ICARDA). This new variety, known to withstand higher temperatures, was tested along the Senegal River during the four months of the year when temperatures reach 35-40 degrees (°C) and it is too hot to grow other varieties. The experiment was conducted in cooperation with research institutes in Mauritania (CNARADA), Senegal (ISRA), and Morocco (Mohammed V University) and showed that this set of durum wheat varieties can withstand up to 40°C heat along the Senegal River basin. The potential impact is estimated at 600,000 tons of new food produced from normally uncultivated land. The high industrial quality of the grains means they could be sold at the international price of $340 per ton, equivalent to a hypothetical business trade of over $200 million per year. This can help farmers gain additional income to diversify their diets, promote children’s education and improve agricultural systems in the region.

As climate change leads to more frequent and severe droughts, the development of these new wheat varieties helps secure food availability for the growing population by withstanding water stress. There are other wheat cultivars specifically developed by scientists for early maturity and higher yield.