Wheat

Wheat is a group of wild and domesticated grasses known as Triticum. People grow these grasses for their grains, which are important foods all around the world. Some well-known types of wheat include common wheat, spelt, durum, emmer, einkorn, and Khorasan or Kamut.

Wheat is grown on more land than any other food crop. In 2024, people grew wheat on over 219 million hectares, and it was the second most-produced cereal after maize. The amount of wheat produced worldwide in 2024 was about 799 million tonnes. As the world’s population grows, the need for wheat is also growing because it has useful proteins that help make many food products.

Wheat gives us important nutrients, like carbohydrates and vegetable proteins. When eaten whole, it also provides many nutrients and dietary fibre. However, for a few people, the proteins in wheat can cause health problems.

Description

Wheat is a strong grass that grows to medium or tall heights. It has a jointed, usually hollow stem that becomes straw after harvest, and many stems can grow from one plant. The leaves are long and narrow, wrapping around the stem at their base. At the top of the stem is a flower head with many flowers. Each flower has both male and female parts and is pollinated by wind, mostly by the plant itself.

The flowers are protected by small leaf-like coverings and are grouped into clusters. After pollination, each flower develops into a grain, which is often called a seed. These grains turn golden yellow when ripe, and the whole cluster is called an ear. Wheat plants produce leaves in a special way, with the last leaf, called the flag leaf, being especially important for making food for the plant. Wheat also has deep roots that can grow up to 2 metres long, helping the plant stay strong. Some types of wheat have special parts called awns that help them grow better in dry, hot places.

History

Main article: History of wheat

People in West Asia collected wild wheat for thousands of years before starting to grow it. Over time, by choosing the best plants, they created wheat that grew better and had bigger grains. This made it easier for farmers to gather the seeds.

Wheat became an important crop in early farming villages. It was easy to grow and store, so it became a main food for many people. Wheat spread from West Asia to places like Greece, Egypt, and even China. Today, wheat is grown all over the world and is a big part of many diets.

Evolution

Phylogeny

Some wheat plants have two sets of tiny parts inside their cells, called chromosomes, while many have four or even six sets. Einkorn wheat has two sets. Most wheats with four sets come from a mix of two wild grasses. These mixes happened long ago in nature. Later, wheats with six sets came from mixing with another wild grass. This created common wheat that many people eat today.

Taxonomy

Main article: Taxonomy of wheat

For thousands of years, people have grown many kinds of wheat, some of which are mixes of different plants. This made it hard to give each type a clear name. Some wild and old wheat types have tough outer layers that stay on the grain. Other kinds, like durum and common wheat, have easier-to-remove outer layers.

As a food

Wheat is a very important food around the world. It can be made into flour, used in bread, pasta, and many other foods. Different countries have their own ways of grouping wheat types, like in Argentina, Australia, Canada, and the United States.

Wheat is a key part of many meals. You can find it in bread, rolls, crackers, biscuits, pancakes, pasta, pies, pastries, pizza, cakes, cookies, muffins, fried foods like doughnuts, breakfast cereals, gravy, porridge, and drinks like beer and a special drink called boza. Wheat also gives food its chewy texture, which helps make bread and pasta.

Wheat provides important nutrients, such as carbohydrates, protein, and several vitamins and minerals. However, some people can have trouble digesting wheat properly, which can make them feel unwell. For these individuals, eating foods without wheat is the best way to stay healthy.

Production and consumption

Main article: International wheat production statistics

In 2024, the world produced 799 million tonnes of wheat. China, India, and Russia were the top producers, making up 42% of all wheat grown. Russia, Canada, the United States, and Ukraine were the biggest exporters, while Egypt, Indonesia, and China were the biggest importers.

Wheat is grown on more land than any other food crop, covering 219.5 million hectares worldwide. It is very important because it can be used to make many processed foods, which people are eating more of as the world changes.

19th century

See also: Wheat production in the United States

During the 1800s, wheat became very important in the British Empire, especially in Australia, Canada, and India. In Australia, new machines helped farmers grow more wheat. In Canada, railways made it easier to send wheat to Britain. By 1930, wheat made up 25% of Canada's exports.

Late 20th century yields

In the second half of the 20th century, scientists and farmers found new ways to grow more wheat, such as using better seeds and adding nutrients to the soil. This helped increase the amount of wheat produced each year.

21st century

Today, changes in the climate are affecting wheat yields in some areas. Wars and changes in trade rules have also made it harder to move wheat around the world.

Agronomy

Growing wheat

Wheat is a crop that grows in one year. It can be planted in autumn and harvested in early summer as winter wheat, or planted in spring and harvested in autumn as spring wheat. The soil is prepared by tilling and harrowing before planting the seeds.

Winter wheat needs cold weather to grow well and does not do well in very hot temperatures. Spring wheat grows best in warm weather but can handle a range of temperatures. Wheat needs deep, rich soil and plenty of rain during the growing season.

Crop development

Wheat usually takes between 110 and 130 days to grow from planting to harvest. Farmers need to understand each stage of growth to care for the crop properly. Knowing when certain stages happen helps protect the plants from weather problems.

Farming techniques

Better farming tools and methods have helped increase wheat production. Using seed drills instead of scattering seeds improved yields. Machines like combine harvesters have made harvesting faster and easier. New wheat varieties have also helped grow more wheat.

Some countries lose wheat after harvesting due to poor storage and transportation. In places like Punjab and North China, irrigation has helped grow more wheat. Using crop rotation and other careful farming practices also helps increase yields.

Main article: British Agricultural Revolution

Pests and diseases

Pests and diseases affect a big part of the world's wheat crop every year.

There are many diseases that affect wheat, mostly caused by tiny living things like fungi, bacteria, and viruses. Scientists work hard to create new types of wheat that can resist these diseases, and farmers use good farming methods to help prevent them. Some diseases are carried on the seeds, while others affect the leaves or roots of the plants. There are also diseases caused by viruses.

Wheat can also be troubled by tiny animals such as insects. For example, a pest called the wheat stem sawfly is a problem in some parts of North America. Birds and rodents can also harm wheat crops by eating the seeds or young plants. Scientists have made special tools to find tiny insects in stored wheat, helping to keep the crop safe.

Breeding objectives

Traditional farming used different types of wheat that farmers saved and planted each year. Modern wheat farming started in the 1800s when scientists began creating special types of wheat by choosing plants with good traits. Today, scientists use genetics to create better wheat.

Goals for improving wheat include growing more wheat, making it resist sickness, and helping it grow in tough conditions. Scientists have used special methods to create new types of wheat since the 1960s, especially in big countries like China. Some wheat has been made to have more nutrients like iron and zinc.

Certain genes in wheat help it grow more. These genes were first used in Japan and helped wheat farms produce more around the world. This was important for growing more food in many places.

Wheat can also get sick from diseases. Scientists have found ways to help wheat fight these diseases by using genes from wild plants. This helps keep wheat healthy and strong.

Scientists are also working on making wheat use water better and resist bugs that can harm the crop. These efforts help farmers grow more wheat with less water and protect it from pests.

Genomics

Decoding the genome

In 2010, scientists decoded most of the genes in a special type of wheat called Chinese Spring line 42. This helped researchers study and improve wheat plants. By 2012, they had mapped almost all the genes in common bread wheat. In 2018, another team shared an even more detailed map of this wheat. By 2020, scientists had mapped the genes of wheat from many places around the world, which helps them find ways to protect wheat from pests and diseases.

Genetic engineering

For many years, scientists have used special methods to change wheat genes. Recently, a powerful tool called CRISPR/Cas9 has been used to make precise changes. For example, scientists have used it to:

• Create wheat that cannot produce seeds in a certain way
• Make wheat better at fighting a harmful fungus
• Improve wheat’s ability to resist certain diseases
• Help wheat survive attacks from specific pests
• Allow wheat to grow even when certain weed-killing sprays are used

In art

The famous Dutch artist Vincent van Gogh painted many pictures of wheat fields between 1885 and 1890. These paintings show wheat crops in different seasons and sometimes include farm workers. One of his last and most famous paintings is called Wheatfield with Crows.

In 1967, American artist Thomas Hart Benton created a painting named Wheat. It shows tall, uncut wheat plants next to rows of cut wheat.

In 1982, American artist Agnes Denes grew a two-acre field of wheat in Battery Park, Manhattan. After harvesting the wheat, it was shared with 28 cities around the world for an art show called "The International Art Show for the End of World Hunger".