The onion with botanical name Allium cepa, also known as the bulb onion or common onion, is a vegetable that is the most widely cultivated species of the genus Allium. Its close relatives include the garlic, shallot and leek
This genus also contains several other species variously referred to as onions and cultivated for food, such as the Japanese bunching onion Allium fistulosum, the tree onion A. proliferum, and the Canada onion Allium canadense. The name “wild onion” is applied to a number of Allium species, but Allium cepa is exclusively known from cultivation. The onion is most frequently a biennial or a perennial plant, but is usually treated as an annual and harvested in its first growing season.
The onion plant has a fan of hollow, bluish-green leaves and its bulb at the base of the plant begins to swell when a certain day-length is reached. The bulbs are composed of shortened, compressed, underground stems surrounded by fleshy modified scale (leaves) that envelop a central bud at the tip of the stem. The crop is harvested and dried and the onions are ready for use or storage. The crop is prone to attack by a number of pests and diseases, particularly the onion fly, the onion eelworm, and various fungi cause rotting. Some varieties of Allium cepa, such as shallots and potato onions, produce multiple bulbs.
Onions are cultivated and used around the world. As a food item, they are usually served cooked, as a vegetable or part of a prepared savoury dish, but can also be eaten raw or used to make pickles or chutneys. They are pungent when chopped and contain certain chemical substances which irritate the eyes.
DESCRIPTION
The onion plant has been grown and selectively bred in cultivation for at least 7,000 years. It is a biennial plant, but is usually grown as an annual. Modern varieties typically grow to a height of 15 to 45 cm (6 to 18 in). The leaves are yellowish- to bluish green and grow alternately in a flattened, fan-shaped swathe. They are fleshy, hollow, and cylindrical, with one flattened side. They are at their broadest about a quarter of the way up, beyond which they taper towards a blunt tip. The base of each leaf is a flattened, usually white sheath that grows out of a basal disc. From the underside of the disc, a bundle of fibrous roots extends for a short way into the soil. As the onion matures, food reserves begin to accumulate in the leaf bases and the bulb of the onion swells.
Culinary uses
Onions are commonly chopped and used as an ingredient in various hearty warm dishes, and may also be used as a main ingredient in their own right, for example in French onion soup, creamed onions, and onion chutney. They are versatile and can be baked, boiled, braised, grilled, fried, roasted, sautéed, or eaten raw in salads. Their layered nature makes them easy to hollow out once cooked, facilitating stuffing them, as in Turkish sogan-dolma. Onions are a staple in Indian cuisine, used as a thickening agent for curries and gravies.
Non-culinary uses
Onions have particularly large cells that are readily observed under low magnification. Forming a single layer of cells, the bulb epidermis is easy to separate for educational, experimental, and breeding purposes.
Onions are, therefore, commonly employed in science education to teach the use of a microscope for observing cell structure. Onions are toxic to dogs, cats, guinea pigs, and many other animals.
NUTRITION
Most onion cultivars are about 89% water, 9% carbohydrates (including 4% sugar and 2% dietary fibre), 1% protein, and negligible fat (table). Onions contain low amounts of essential nutrients and have an energy value of 166 kJ (40 Calories) in a 100 g (3.5 oz) amount. Onions contribute savoury flavour to dishes without contributing significant caloric content.
Phytochemicals
Considerable differences exist between onion varieties in phytochemical content, particularly for polyphenols, with shallots having the highest level, six times the amount found in Vidalia onions. Yellow onions have the highest total flavonoid content, an amount 11 times higher than in white onions. Red onions have considerable content of anthocyanin pigments, with at least 25 different compounds identified representing 10% of total flavonoid content. Onion polyphenols are under basic research to determine their possible biological properties in humans.
Some people suffer from allergic reactions after handling onions.[38] Symptoms can include contact dermatitis, intense itching, rhinoconjunctivitis, blurred vision, bronchial asthma, sweating, and anaphylaxis. Allergic reactions may not occur when eating cooked onions, possibly due to the denaturing of the proteins from cooking.
CULTIVATION
Onions are best cultivated in fertile soils that are well-drained. Sandy loams are good as they are low in sulphur, while clayey soils usually have high sulphur content and produce pungent bulbs. Onions require a high level of nutrients in the soil. Phosphorus is often present in sufficient quantities, but may be applied before planting because of its low level of availability in cold soils. Nitrogen and potash can be applied at regular intervals during the growing season, the last application of nitrogen being at least four weeks before harvesting. Bulbing onions are day-length sensitive; their bulbs begin growing only after the number of daylight hours has surpassed some minimal quantity. Onions are a cool-weather crop. Hot temperatures or other stressful conditions cause them to “bolt“, meaning that a flower stem begins to grow.
Onions may be grown from seed or from sets. Onion seeds are short-lived and fresh seeds germinate better. The seeds are sown thinly in shallow drills, thinning the plants in stages. Routine care during the growing season involves keeping the rows free of competing weeds, especially when the plants are young. The plants are shallow-rooted and do not need a great deal of water when established. Bulbing usually takes place after 12 to 18 weeks. The bulbs can be gathered when needed to eat fresh, but if they will be kept in storage, they should be harvested after the leaves have died back naturally. In dry weather, they can be left on the surface of the soil for a few days to dry out properly and then they can be placed in nets, roped into strings, or laid in layers in shallow boxes. They should be stored in a well-ventilated, cool place such as a shed.
Pests and diseases
Onions suffer from a number of plant disorders. The most serious are likely to be the onion fly, stem and bulb eelworm, white rot, and neck rot. Diseases affecting the foliage include rust and smut, downy mildew, and white tip disease. The bulbs may be affected by splitting, white rot, and neck rot. Shanking is a condition in which the central leaves turn yellow and the inner part of the bulb collapses into an unpleasant-smelling slime. Most of these disorders are best treated by removing and burning affected plants. The larvae of the onion leaf miner or leek moth (Acrolepiopsis assectella) sometimes attack the foliage and may burrow down into the bulb.
The onion fly (Delia antiqua) lays eggs on the leaves and stems and on the ground close to onion, shallot, leek, and garlic plants. The fly is attracted to the crop by the smell of damaged tissue and is liable to occur after thinning. Plants grown from sets are less prone to attack. The larvae tunnel into the bulbs and the foliage wilts and turns yellow. The bulbs are disfigured and rot, especially in wet weather. Control measures may include crop rotation, the use of seed dressings, early sowing or planting, and the removal of infested plants.
The onion eelworm (Ditylenchus dipsaci), a tiny parasitic soil-living nematode, causes swollen, distorted foliage. Young plants are killed and older ones produce soft bulbs. No cure is known and affected plants should be uprooted and burned. The site should not be used for growing onions again for several years and should also be avoided for growing carrots, parsnips, and beans, which are also susceptible to the eelworm.
White rot of onions, leeks, and garlic is caused by the soil-borne fungus Sclerotium cepivorum. As the roots rot, the foliage turns yellow and wilts. The bases of the bulbs are attacked and become covered by a fluffy white mass of mycelia, which later produces small, globular black structures called sclerotia. These resting structures remain in the soil to re-infect a future crop. No cure for this fungal disease exists, so affected plants should be removed and destroyed and the ground used for unrelated crops in subsequent years.
Neck rot is a fungal disease affecting onions in storage. It is caused by Botrytis allii, which attacks the neck and upper parts of the bulb, causing a grey mould to develop. The symptoms often first occur where the bulb has been damaged and spread downwards in the affected scales. Large quantities of spores are produced and crust-like sclerotia may also develop. In time, a dry rot sets in and the bulb becomes a dry, mummified structure. This disease may be present throughout the growing period, but only manifests itself when the bulb is in storage. Antifungal seed dressings are available and the disease can be minimised by preventing physical damage to the bulbs at harvesting, careful drying and curing of the mature onions, and correct storage in a cool, dry place with plenty of circulating air.
PRODUCTION
In 2014, world production of dried onions was 88.5 million tonnes, led by China and India producing 25% and 22% of the total, respectively. Nigeria has all it takes to match these countries given the disposition of government towards agriculture.
The major inputs for commercial ONION farming are; LAND, IMPROVED CULTIVARS, TRAINING, FERTILIZER, DISEASE AND PEST CONTROL, FINANCE and MARKET.
LAND
Procuring Land for such commercial farming has to be done by professionals who have the eagle eye to decode the soil texture without much examination. It is also easier to source for land for agriculture through professionals because they have extensive network and can arrange Land for you in short notice and in a cost effective manner. There is little need to purchase land for farming in large scale from the beginning as this will tie down available capital, thus it is advisable to lease and subsequently pay for the land from the proceed of the farm. BUSINESS ADVISORY NETWORK is a guru in this regard and will help you arrange choice farm land at the best rate, all you have to do is to talk to us.
TRAINING
We will guide you on best planting season, spacing, fertilizer type, how to source fertilizer, fertilizer application. Weed control, Crops you may intercrop with ONION, the effects of intercropping on ONION yield, Storage and processing.
FINANCE
The central bank of Nigeria has a lot of incentives/ credits for commercial farmers at a reduced interest rate of 9% per annum. Most of these are organized by the central bank of Nigeria although accessed through the commercial bank. BAN will guide you on how to source credit under any of these credits listed below;
Agricultural Credit Guarantee Scheme Fund (ACGSF) The Fund guarantees credit facilities extended to farmers by banks up to 75% of the amount in default net of any security realized. The Fund is managed by the Central Bank of Nigeria, through this guarantee it is easy For commercial banks to loan to farmers not fearing
Agricultural Credit Support Scheme (ACSS) ACSS funds are disbursed to farmers and agro-allied entrepreneurs at a single-digit interest rate of 8.0 percent. At the commencement of the project support, banks will grant loans to qualified applicants at 14.0 per cent interest rate. Applicants who pay back their facilities on schedule are to enjoy a rebate of 6.0 per cent, thus reducing the effective rate of interest to be paid by farmers to 8.0 per cent.
Commercial Agriculture Credit Scheme (CACS) This credit scheme is specifically targeted to finance the country’s agricultural value chain (production, processing, storage and marketing). The maximum interest rate to the borrower under the scheme shall not exceed 9 per cent, inclusive of all charges.
Nigeria Incentive Based Risk Sharing System for Agricultural Lending ( NIRSAL) Risk is the single-most important factor that prevents banks from lending to agriculture. To change banks’ perception that agriculture is a high-risk sector, NIRSAL has a USD300 Million Risk-Sharing Facility that it uses to share their losses on agricultural loans through Credit Risk Guarantees. NIRSAL shares risk with banks ranging from 30% to 75% of face value depending on segment.
This also includes a guarantee fee of 1% per annum on outstanding protected principal and interest. Up to 40% of interest cost rebated to select value chain participants every 90 days if loan remains in good standing (no partial or full default). All crops, livestock and related supportive economic activity across the value chain are supported by this facility.
The news is that government is willing and doing everything to encourage farming in Nigeria because that’s where the country straight lies. Nigeria is endowed with arable land and fresh water resources when viewed as a whole with approximately 61 million hectares of the land cultivable while the total renewable water resources is about 280 km3/year; which include river Niger, river Benue, lake Chad, Osun river, Hadejia River, Bonny river and a host of others. The major soil types in Nigeria, according to FAO soil taxonomist are fluvisols, regosols, gleysols, acrisols, ferrasols, alisols, lixisols, cambisols, luvisols, nitosols, arenosols and vertisols. These soil types vary in their potential for agricultural use according to FAO.
Nigerian soils can be classified into groups made up of four (climatic) zones that are soil associations. The groups are:
- Northern zone of sandy soils
- Interior zone of laterite soils
- Southern belt of forest soils
- Alluvial soils Zones
Northern zone of sandy soils: This area lies in the very northern parts of the country. This area lies in the extreme north with proximity to the fringes of the fast- encroaching Sahara desert. It is characterized by soils formed by deposition of sand by the wind. These soils might have been formed from wind-sorted desert sands that accumulated over long periods of time when the Sahara desert encroached several kilometers south of its present limits. The soils of this zone are very good in the production of groundnut, sorghum, cowpea, and millet.
Interior zone of laterite soils: This zone is made up of a mixture of sand and clay. They are grey to black clay, poorly drained and seasonally flooded forming the “fadama”. The Biu Plateau has rich soil that is productive and offers prospects for the expansion of the areas of cotton production, soybeans, yam and other legumes.
Southern belt of forest soils: Soils in this zone broadly represent those of the humid, tropical forest climate zones of the south where the wet season is long, the harmattan season short and forest cover is dense. Local soil types depend largely on parent rock; where the underlying rocks are granite or clay, the soils is a rich clayey loam. These soils are very good in growing crops like cocoa, oil palm, rubber, Cassava.
Zone of alluvial soils: These soils are found along the flooded plains of rivers, deltas, along the coastal flats. This zone extends from the coastal inland and runs along the valleys of the Niger and the Benue rivers, thus cutting across the vegetational zones. Soils in this zone are characteristic of fresh-water soil of grey to white sand, grey clay and sandy clay with humid topsoil. Another group consists of brownish to black saline mangrove soils, with a mat of rootlets. This soil type is very good for rice etc.
FARM EQUIPMENT
BAN will also help in securing farming equipment. This may be achieved through the federal and state government partnership with the support of any of the credit schemes. Through this farm equipment can be acquired or leased.
MARKET
Demand for ONION is high both locally and internationally. It is important to point out that Nigeria is yet to produce enough onion for local consumption so investment in this area will yield great returns.
SECURITY
Security of the farm is of utmost importance, thus adequate security must be put in place to eliminate/ reduce pilferage in the farm.