# Commercial sorghum

Commercial sorghum is the cultivation and commercial exploitation of species of grasses within the genus Sorghum (often S. bicolor, sometimes Sorghum arundinaceum). These plants are used for grain, fibre and fodder. The plants are cultivated in warmer climates worldwide. Commercial Sorghum species are native to tropical and subtropical regions of Africa and Asia.
Other names include durra, Egyptian millet, feterita, Guinea corn, jwari ज्वारी (Marathi), jowar, juwar, milo, shallu, Sudan grass, cholam (Tamil), jola/ಜೋಳ (Kannada), jonnalu జొన్నలు (Telugu), gaoliang (zh:高粱), great millet, kafir corn, dura, dari, mtama, and solam.
Sorghum has been, for centuries, one of the most important staple foods for millions of poor rural people in the semiarid tropics of Asia and Africa. For some impoverished regions of the world, sorghum remains a principal source of energy, protein, vitamins and minerals. Sorghum grows in harsh environments where other crops do not grow well, just like other staple foods, such as cassava, that are common in impoverished regions of the world. It is usually grown without application of any fertilizers or other inputs by a multitude of small-holder farmers in many countries.
Grain sorghum is the third most important cereal crop grown in the United States and the fifth most important cereal crop grown in the world. In 2010, Nigeria was the world's largest producer of grain sorghum, followed by the United States and India. In developed countries, and increasingly in developing countries such as India, the predominant use of sorghum is as fodder for poultry and cattle. Leading exporters in 2010 were the United States, Australia and Argentina; Mexico was the largest importer of sorghum.
An international effort is under way to improve sorghum farming. The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) has improved sorghum using traditional genetic improvement and integrated genetic and natural resources management practices. New varieties of sorghum from ICRISAT has now resulted in India producing 7 metric tons per hectare (2.8 long ton/acre; 3.1 short ton/acre). Some 194 improved cultivars are now planted worldwide. In India, increases in sorghum productivity resulting from improved cultivars have freed up 7 million hectares (17 million acres) of land, enabling farmers to diversify into high-income cash crops and boost their livelihoods. Sorghum is used primarily as poultry feed, and secondarily as cattle feed and in brewing applications.

## Origin

The last wild relatives of commercial sorghum are currently confined to Africa south of the Sahara — although Zohary and Hopf add "perhaps" Yemen and Sudan — indicating its domestication took place there. However, note Zohary and Hopf, "the archaeological exploration of sub-Saharan Africa is yet in its early stages, and we still lack critical information for determining where and when sorghum could have been taken into cultivation." Although rich finds of S. bicolor have been recovered from Qasr Ibrim in Egyptian Nubia, the wild examples have been dated to circa 800–600 BC, and the domesticated ones no earlier than AD 100. The earliest archeological evidence comes from sites dated to the second millennium BC in India and Pakistan — where S. bicolor is not native. These incongruous finds have been interpreted, according again to Zohary and Hopf, as indicating: (i) an even earlier domestication in Africa, and (ii) an early migration of domestic sorghum, from East Africa into the Indian subcontinent. This interpretation got further support because several other African grain crops, namely: pearl millet Pennisetum glaucum (L.) R. Br., cow pea Vigna unguiculata (L.) Walp., and hyacinth bean Lablab purpureus (L.) Sweet show similar patterns. Their wild progenitors are restricted to Africa.
Most cultivated varieties of sorghum can be traced back to Africa, where they grow on savanna lands. During the Arab Agricultural Revolution, sorghum was planted extensively in parts of the Middle East, North Africa and Europe. Despite the antiquity of sorghum, it arrived late to the Near East. It was unknown in the Mediterranean area into Roman times. Tenth century records indicate it was widely grown in Iraq, and became the principal food of Kirman in Persia. In addition to the eastern parts of the Muslim world, the crop was also grown in Egypt and later in Islamic Spain. From Islamic Spain, it was introduced to Christian Spain and then France (by the 12th century). In the Muslim world, sorghum was typically grown in areas where the soil was poor or the weather too hot and dry to grow other crops.

## Cultivation

Sorghum is used for food, fodder, and the production of alcoholic beverages. It is drought-tolerant and heat-tolerant, and is especially important in arid regions. It is an important food crop in Africa, Central America, and South Asia, and is the "fifth most important cereal crop grown in the world".

### Use as fodder

The FAO reports that 440,000 square kilometres (110,000,000 acres) were devoted worldwide to sorghum production in 2004. In the US, sorghum grain is used primarily as a maize (corn) substitute for livestock feed because their nutritional values are very similar. Some hybrids commonly grown for feed have been developed to deter predation by birds, and therefore contain a high concentration of tannins and phenolic compounds, which necessitates additional processing to allow the grain to be digested by cattle.

### Growing grain sorghum

Top sorghum producers — 2022 — metric tons (long tons; short tons) :
| Nigeria | 6.8 (6.7; 7.5) |
| Sudan | 5.2 (5.1; 5.7) |
| United States | 4.8 (4.7; 5.3) |
| Mexico | 4.8 (4.7; 5.3) |
| Ethiopia | 4.2 (4.1; 4.6) |
| India | 4.2 (4.1; 4.6) |
| China | 3.2 (3.1; 3.5) |
| Brazil | 2.9 (2.9; 3.2) |
| Argentina | 2.9 (2.9; 3.2) |
| Australia | 2.6 (2.6; 2.9) |
| World Total | 57.6 (56.7; 63.5) |
Sorghum requires an average temperature of at least 25 °C (77 °F) to produce maximum grain yields in a given year. Maximum photosynthesis is achieved at daytime temperatures of at least 30 °C (86 °F). Night time temperatures below 13 °C (55 °F) for more than a few days can severely reduce the plants' potential grain production. Sorghum cannot be planted until soil temperatures have reached 17 °C (63 °F). The long growing season, usually 90–120 days, causes yields to be severely decreased if plants are not in the ground early enough.
Grain sorghum is usually planted with a commercial corn seeder at a depth of 2–5 centimetres (3⁄4–2 in), depending on the density of the soil (shallower in heavier soil). The goal in planting, when working with fertile soil, is 50,000 to 300,000 plants per hectare (20,000 to 121,000/acre). Therefore, with an average emergence rate of 75%, sorghum should be planted at a rate of 2–12 kilograms per hectare (1.8–10.7 lb/acre) of seed.
Yields have been found to be boosted by 10–15% when optimum use of moisture and sunlight are available, by planting in 25-centimetre (10 in) rows instead of the conventional 1-metre (3 ft 3 in) rows.
Sorghum, in general, is a very competitive crop, and does well in competition with weeds in narrow rows. Sorghum produces a chemical compound called sorgoleone (an Alkylresorcinol), which the plant uses to combat weeds. The chemical is so effective in preventing the growth of weeds it sometime prohibits the growth of other crops harvested on the same field. To address this problem, researchers at the Agricultural Research Service found two gene sequences believed to be responsible for the enzymes that secrete the chemical compound sorgoleone. The discovery of these gene sequences will help researchers one day in developing sorghum varieties that cause less soil toxicity and potentially target gene sequences in other crops to increase their natural pesticide capabilities, as well.
Insect and diseases are not prevalent in sorghum crops. Birds, however, are a major source of yield loss. Hybrids with higher tannin content and growing the crop in large field blocks are solutions used to combat the birds. The crop may also be attacked by corn earworms, aphids, and some Lepidoptera larvae, including turnip moths.
It is a very high nitrogen-feeding crop. An average hectare producing 6.3 tonnes of grain yield requires 110 kg of nitrogen (242 lb 8 oz for 2.5 long ton/acre; 2.8 short ton/acre), but relatively small amounts of phosphorus and potassium (15 kilograms (33 lb 1 oz) of each).
Sorghum's growth habit is similar to that of maize, but with more side shoots and a more extensively branched root system. The root system is very fibrous, and can extend to a depth of up to 1.2 metres (3 ft 11 in). The plant finds 75% of its water in the top metre of soil, and because of this, in dry areas, the plant's production can be severely affected by the water holding capacity of the soil. The plants require up to 70–100 millimetres (2+3⁄4–4 in) of moisture every 10 days in early stages of growth, and as sorghum progresses through growth stages and the roots penetrate more deeply into the soil to tap into hidden water reserves, the plant needs progressively less water. By the time the seed heads are filling, optimum water conditions are down to about 50 millimetres (2 in) every 10 days. Compacted soil or shallow topsoil can limit the plant's ability to deal with drought by limiting its root system. Since these plants have evolved to grow in hot, dry areas, it is essential to keep the soil from compacting and to grow on land with ample cultivated topsoil.
Wild species of sorghum tend to grow to a height of 1.5–2 metres (4 ft 11 in – 6 ft 7 in); however, due to problems this height created when the grain was being harvested, in recent years, cultivars with genes for dwarfism have been selected, resulting in sorghum that grows to between 60 and 120 centimetres (2 ft 0 in and 3 ft 11 in) tall.
Sorghum's yields are not affected by short periods of drought as severely as other crops such as maize, because it develops its seed heads over longer periods of time, and short periods of water stress do not usually have the ability to prevent kernel development. Even in a long drought severe enough to hamper sorghum production, it will still usually produce some seed on smaller and fewer seed heads. Rarely will one find a kernelless season for sorghum, even under the most adverse water conditions. Sorghum's ability to thrive with less water than maize may be due to its ability to hold water in its foliage better than maize. Sorghum has a waxy coating on its leaves and stems which helps to keep water in the plant, even in intense heat.

### Weeds

Shattercane (weedy S. bicolor) is an unusually problematic weed of sorghum. Because it intercrosses fairly freely it will take on herbicide resistance traits which are meant to protect the crop and be useful to the farmer. Werle et al., 2016 finds this is governed by genetic distance but all genotypes do this. They also find that it seems impossible at first to completely be rid of Inzen shattercane once it has been produced, even with rotation completely out of sorghum. However by introducing realistic stochasticity they find promising possibilities of stochastic extinction at low levels. Some of these modes produce population dynamics which are chaotic, and some of these progress to extinction.

## Uses
### Culinary use

In arid, less developed regions of the world, sorghum is an important food crop, especially for subsistence farmers. It is used to make such foods as couscous, sorghum flour, porridge and molasses.
Bhakri (jolada rotti in northern Karnataka), a variety of unleavened bread usually made from sorghum, is the staple diet in many parts of India, such as Maharashtra state and northern Karnataka state. In eastern Karnataka and the Rayalaseema area of Andhra Pradesh, roti (jonna rotte) made with sorghum is the staple food.
In South Africa, sorghum meal is often eaten as a stiff porridge much like pap. It is called mabele in Northern Sotho and "brown porridge" in English. The porridge can be served with maswi (soured milk) or merogo (a mixture of boiled greens much like collard greens or spinach).
In Ethiopia, sorghum is fermented to make injera flatbread, and in Sudan it is fermented to make kisra. In India, dosa is sometimes made with a sorghum-grain mixture, but rice is more commonly used in place of sorghum.
In the cuisine of the Southern United States, sorghum syrup was used as a sweet condiment, much as maple syrup was used in the North, usually for biscuits, corn bread, pancakes, hot cereals or baked beans. It is uncommon today.
In Arab cuisine, the unmilled grain is often cooked to make couscous, porridges, soups, and cakes. Many poor use it, along with other flours or starches, to make bread. The seeds and stalks are fed to cattle and poultry. Some varieties have been used for thatch, fencing, baskets, brushes and brooms, and stalks have been used as fuel. Northern Karnataka in India, they make chappathis from jola.
Sorghum seeds can be popped in the same manner as popcorn (i.e., with oil or hot air, etc.), although the popped kernels are smaller than popcorn (see photo on the right).
Sorghum sometimes is used for making tortillas (e.g., in Central America). In El Salvador, they sometimes use sorghum (maicillo) to make tortillas when there is not enough corn.
Since 2000, sorghum has come into increasing use in homemade and commercial breads and cereals made specifically for the gluten-free diet.

### Alcoholic beverages
#### Sorghum beer

In southern Africa, sorghum is used to produce Kaffir beer, including the local version of Guinness. In recent years, sorghum has been used as a substitute for other grain in gluten-free beer. Although the African versions are not "gluten-free", as malt extract is also used, truly gluten-free beer using such substitutes as sorghum or buckwheat are now available. Sorghum is used in the same way as barley to produce a "malt" that can form the basis of a mash that will brew a beer without gliadin or hordein (together "gluten") and therefore can be suitable for coeliacs or others sensitive to certain glycoproteins.
Sorghum beer is associated with the development of the segregationist "Durban System" in South Africa in the early 20th century. The turn of the 20th century saw growing segregationist tendencies among the white populations of South African towns. Fearful of the alleged diseases of black residents, the white populations of these towns sought to prevent black Africans from gaining permanent residence in urban areas, and separate them from the white communities. Within this context, two municipalities, Durban and Pietermaritzburg, devised a system by which black Africans in their locality would be housed in 'native locations' outside the main towns, with their segregated accommodation paid for from revenues from the municipal monopoly over sorghum beer. This solved the problem of white rate-payers having to foot the cost of segregation, and ensured the whole scheme paid for itself. After the passage of the 1923 Natives (Urban Areas) Act, all municipalities in South Africa were given the powers to enforce racial segregation, and the Durban System was extended throughout the union, ensuring that segregation was paid for from African rents and beerhall monopolies.
The souring of African sorghum beer by lactic acid fermentation is responsible for the distinct sour taste. Souring may be initiated using yogurt, sour dough starter cultures, or by spontaneous fermentation. The natural microflora of the sorghum grain maybe also be the source of lactic acid bacteria; a handful of raw grain sorghum or malted sorghum may be mixed in with the wort to start the lactic acid fermentation. Although many lactic acid bacteria strains may be present, Lactobacillus spp. is responsible for the lactic acid fermentation in African sorghum beer.
Commercial African sorghum beer is packaged in a microbiologically active state. The lactic acid fermentation and/or alcoholic fermentation may still be active. For this reason, special plastic or carton containers with vents are used to allow gas to escape. Spoilage is a big safety concern when it comes to African sorghum beer. Packaging does not occur in sterile conditions and many microorganisms may contaminate the beer. Also, using wild lactic acid bacteria increases the chances of spoilage organisms being present. However, the microbiologically active characteristic of the beer also increases the safety of the product by creating competition between organisms. Although aflatoxins from mould were found on sorghum grain, they were not found in industrially produced African sorghum beer.

### Other uses

Sorghum straw (stem fibres) can also be made into excellent wallboard for house building, as well as biodegradable packaging. Since it does not accumulate static electricity, it is also used in packaging materials for sensitive electronic equipment.
Sorghum, like sugarcane, yields four times as much ethanol as maize on bioconversion.