Onion.docx

NAME : FERY HAIDIR IRAWAN NIM : F34160069 LECTURER : Prof. Marimin

ONIONS

The History Onions have been used by humans since the Neolithic age,and they are still being used all over the world. Over thislong period, there have always been people who haveappreciated the use of onions and used them in consider-able quantities, but there have also been those who haverejected and detested them.Onions have been cultivated globally, in at least 175countries, for around 5000 years. Ancient Egyptiansregarded the spherical bulb as a symbol of the universe.The name is probably is taken from the Latin unusmeaning “one,”and the Romans introduced the onionto Britain, from where it may have been carried to theAmericas (Burnie et al 1999). The first known writtenreport about the onion comes from the Sumerians anddates back to 2600–2100 BC. In the Papyrus Ebers, which isbased on ancient Egyptian writings and knowledge, we discover that leek played an important role in thekingdom of old Egypt. The great physician Hippocratessuggested onion as a diuretic, laxative, and emmena-gogue. He also used onion for the treatment of pneumo-nia, and, externally, for healing putrid wounds. The Botany The genus Allium is very large and consists of many wildedible species (only a small fraction is cultivated com-mercially), and is widely distributed over temperate zonesin the northern hemisphere. The place of origin is purported to be in centralAsia, and the Mediterranean regions are considered to bethe secondary centre of origin. The genus Allium contains more than 780 species (Burnie et al.,1999) with large diversities in morphological characters.The chromosome number of onion is 16 (2n). It has beenclassified in hierarchical level as follows: Kingdom: Plantae Subkingdom: Tracheobionta Super division: Spermatophyta Division: Liliopodia Subclass: Liliales Order: Liliaceae Genus: Allium Species: Allium cepa L. Onion belongs to the family Amaryllidaceae; the plant iseither biannual or perennial (depending on the cultivar),and smells when crushed. The plant hasshallow adventitious fibrous roots (Ranjitkar 2003), bulb,and tubular leaves. The stem grows

NAME : FERY HAIDIR IRAWAN NIM : F34160069 LECTURER : Prof. Marimin

100–200 cm tallduring the second year of the plant’s life. The green leavesof the plant are an extension of the outer food storageleaves. The inflorescence is umbel-like and develops froma ring-like apical meristem. The umbel is the aggregationof flowers at various stages of development, and it con-tains 200–600 small individual flowers, although thisnumber can range from 50 to 1000. It iscomposed of white or greenishwhite small flowers whichgrow at the tip of the stem in the second year of the plant.The onion bulb ranges in shape from flat to globular tooblong, and the onions are usually of three colors: red,white, and yellow. The fruits are capsuleand contain black seeds. The bulb is composed of fleshyand enlarged leaf bases. The edible onion bulb can growup to 10 cm in diameter, and it is composed of severaloverlapping layers on a central core. The outer leaf basesof the bulb lose moisture and become scaly by the time of harvesting, and the inner leaves thicken as the bulbdevelops. The majority of the species of onion grow inopen, sunny, and dry land, mainly in humid climates.However, the Allium species have been adopted in otherecological niches of the world (Fritsch and Friesen 2002). The onion plants grow in areas that have evenly distributed rainfall throughout the year and include plants that require quite long exposure to the sun, more than 4 hours / day. If it is too short or is in a shaded or protected place so that it does not get enough sunlight, the production is low, it feels rather tasteless, and cannot last long. Therefore, the onion is planted in a cool place. The air temperature is good for plant growth of 18-20o C. At lower temperatures 1 - 1.5o C, onions are still able to form flowers. The air condition with relative humidity ranges from 80-90% (quite moist) is very good for the growth of onion plants. The optimum height that is suitable for onion cultivation is ± 1,500 m asl, with sufficient sunlight, and a soil pH of 5.5 to 6.5. Land suitable for onions is fertile soil, lots of topsoil, and loose. Soil should be easy to carry on water so it is not easy to muddy and solidify. The best type of soil is sandy clay or dusty clay, which is a soil that has a balanced ratio between clay, sand and dust fractions. The Productivity management Onion is an extensively grown biennial bulb crop, withworld production of 74,250,809 tonnes from an area of4,364,000 hectares. China and India are theprimary onion growing countries, followed by the USA,Egypt, Iran, Turkey, Pakistan, Brazil, the Russian Federa-tion, and the Republic of Korea (FAO, 2012). Onionproductivity is highest in the Republic of Korea(66.16 t/ha), followed by the USA (56.26 t/ha), Spain(53.31 t/ha), and the Netherlands (51.64 t/ha); the averageproductivity across the world is 19.79 t/ha. From aneconomic point of view, the international trade in onionexports is 6.77 million tonnes. The Netherlands is thehighest onion exporter (1.33 million tonnes) followed byIndia, China, Egypt, Mexico, USA, Spain, and Argentina.Bangladesh, Malaysia, the Russian Federation, the UK,Japan, and Saudi Arabia are the major onion importing countries in the world. Rank 1

Country China

Total Production (Tonnes) 20,507,759

NAME : FERY HAIDIR IRAWAN NIM : F34160069 LECTURER : Prof. Marimin

2 3 4 5 6 7 8 9 10

India USA Egypt Iran Turkey Paskitan Brazil Russia Republic of Korea

13,372,100 3,320,870 2,208,080 1,922,970 1,900,000 1,701,100 1,556,000 1,536,300 1,411,650

The improved agronomic management is an important practice to reduce the yield gap and to enhance the food security within an area and among farming households. A plant population density is one of the important agronomic factors which can limit the onion production and productivity. According to Winch (2006) report, a plant which has been grown too close together are competing for sunlight, essential nutrients, water, and air that leads to producing small bulb with a low quality whereas a plant which has grown too far apart produces vigor individual plant but low yield per given areas. Hence different onion varieties have responded differently to various plant spacing’s. Water availability is the main limiting factor of crop productivity than all of the rests due to its paramount importance for normal plant growth and developments. Hence, due to its shallow root system and needs frequent irrigation water after a short interval, onion is susceptible to water stress as compared to other crops. Knowing a number of water requirements of onion based on the specific area is basically important to produce the optimum onion yields. Bossie (2009) elaborated that, knowing of the water requirement and the coefficient values of the crop can help to accurately plan and manage the irrigation water for onion production at different locations even an area where a water shortage is very critical. Therefore, assuming of high irrigation frequency and better scheduling method may be expected to increase the applied fertilizer use efficiency, reduces leaching effects and to improve onion yields by increasing bulb sizes. Bombay red is the most widely grown onion variety under irrigation water in the country due to its higher bulb yield, earliness and susceptible to the rotting disease under a rainfed condition at maturity stage (Nikus and Mulugeta, 2013). As a result, knowing of the individual crop water requirements help to produce more than two times per annum to ensure the year-round production of onion in order to get a high return as well as to reduce the susceptibility of the crop to various diseases and insect pests. Disease and insect pests are the most important yield reducing factor for different vegetable crop production systems including of onion. Onion is the crop that can be easily susceptible to diverse biotic and abiotic stresses. Diverse types of pathogens are affecting the crop by causing diverse diseases based on the available conducive environmental interactions with susceptible cultivars. As a result, several

NAME : FERY HAIDIR IRAWAN NIM : F34160069 LECTURER : Prof. Marimin

farmers in Gojjam zone of Amhara region has shifted to shallot rather than onion production due to disease severity and other observed problems in the area. The same is true for other parts of the country which take the lion share of onion yield reduction. Some diseases were identified as causing huge loss unless treated based on their types and causes of diseases. Based on this, different fungal pathogens are attacking the crop by causing the economic losses. Botrytis leaf blight (BLB) or neck rot is one of fungal disease which affects only onion in cool climate areas on worldwide. The disease is primarily the storage disease which may infect by spores blown from infected onion debris and improperly disposed of cull piles. Fusarium basal rots (fusariumoxysporum) also identified as another fungal disease-causing pathogen of onion in Ethiopia. The yield losses by basal rot can be more than 50% which can effects by attacking of the cloves and seedlings, causing pre and post-emergence damping off, root rot of older plants, and steam plate discoloration and basal rot of bulbs in the field and storage (Zeleke and Derso 2015). The disease can be controlled by preventing the disease occurrences and by applying of fungicide chemical. Thrips is one of the challenging insect pests of onion which mainly affects the leaf parts of the plant that reduces the yield and productivity of the crop. Currently, however, different research work has been undertaking by focusing on the identification of different disease and insect pests and their mitigation strategies to overcome the observed problems and to boost the production and productivity of the crop in the country. Wet Slices Feed

Dry Slices

Dry Veggie

Pickle

Seed

Flour

Consumed Tuber

Paste

Fertilizer

Extract

Fuel

Instant season

Leaves

Onion

Tuber

Outer Layer

Oleoresin

Medicine

Frying onion

Illustration 1 Industrial Derivatives Tree of Onion

NAME : FERY HAIDIR IRAWAN NIM : F34160069 LECTURER : Prof. Marimin

Onions not only provide flavor, but also provide healthpromoting phytochemicals. Phytochemicals are naturalcompounds found in onions which have the potential topromote health benefits in humans and offer protectionfrom a variety of diseases, including cancer. The organo-sulfur compounds have antimicrobial, antiallergenic,anti-inflammatory, and antithrombotic activity. As well as this, flavonols in onions, suchas quercetin and kaempferol, also possess different crucialbiological roles for health maintenance, like antiviral,antimicrobial, anti-inflammatory, and anticancer activity,along with protection of the heart and brain. It is a well established fact that flavonoids have antiox-idant properties. It is the best studied and describedactivity of onion flavonoids, which protect cells andtissues against reactive oxygen species (ROS). ROS pro-duce free radicals, which damage the cells of differentorgans exogenously. It has also been provedin vitro that flavonoids, such as quercetin and kaempferol,stabilize the free electrons that originate from ROS. The hydroxyl configuration of the B ring of flavonoids has a significant rolein the scavenging of ROS, by donating hydrogen and anelectron to hydroxyl and peroxyl, to stabilize them. The flavonoid heterocycle initiates conjuga-tion between a free 3-OH and the aromatic rings, whichleads to antioxidant activity. Moreover,reports reveal that position, number, occurrence andnumber of sugar residues play a crucial role in antioxidantactivity (Ratty and Das 1988). The major flavonoid found in onion is quercetin, pres-ent in conjugated form as quercetin 4´-O-β-glycopyrano-side, quercetin 3,4´-O-β-diglycopyranoside, and quercetin3,7,4´-O-β-triglycopyranoside. The dry outer layers of onion, which are discardedbefore food processing such as cooking, contain largeamounts of quercetin, quercetin glycoside, and theiroxidative products (Gulsen et al 2007), which are effective antioxidants against non-enzymatic lipid peroxida-tion and oxidation of lowdensity lipoproteins (LDL).Quercetin, and its dimerized compound, show the highestantioxidative activity, which is comparable to that ofα-tocopherol. Therefore, the outer layer extract of onionis expected to be a resource for food ingredients. Quercetin is one of the most studied flavonoids thatinhibits bacterial growth. It has showngreat potential to inhibit the growth of Staphylococcusaureus completely. Experiments haveshown that kaempferol works as an inhibitor againstHelicobacter pylori.It has been reported that onion and garlic extracts exertbactericidal effects towards Streptococcus mutans,Strep-tococcus sobrinus,Porphyromonas gingivalis, and Prevo-tella intermedia (Gram-positive bacteria), considered asthe main bacteria responsible for dental caries and adultperiodontitis, respectively.However, onion is not effective against Gram-negativebacteria. In addition to organosulfurcompounds, it has been reported that certain quercetinoxidation products found in onion also present antibac-terial activity against H. pylori and MRSA (multidrug-resistant S. aureus) (Ramos et al 2006). Phytochemicals found in onions, such asquercetin and kaempferol, play a big role in reducing thegrowth of various viruses.Moreover, quercetin and kaempferol have shown the irvirucidal activity against the herpes simplextype I virus, rabies virus, polio

NAME : FERY HAIDIR IRAWAN NIM : F34160069 LECTURER : Prof. Marimin

virus, mengo virus, pseu-dorabies virus, sindbis virus, and parainfluenza type 3virus. As well as this, cell culture datahave shown that the quercetin flavonol may inhibit thereplication of different respiratory viruses, reducing theirviral count.Quercetin also enhances the bioavailability of some anti-viral drugs (Wu et al 2005). Lectins are a very heteroge-neous group of glycoproteins, with the ability to recognizeand bind specifically to carbohydrate ligands. Onionlectins have a pronounced anti-HIV activity.

REFERRENCES Burnie G, Forrester S, and Greig D. 1999. Botanica: The Illustrated A-Z of over 10,000 Garden Plants 3rd Edition. New South Wales(Au): Random House. Fritsch R, Friesen N. 2002. Evolution, domestication, and taxonomy. In: Rabinowitch HD, Currah L. EdsWallingford(UK): CABIPublishing Ranjitkar HD. 2003. A Handbook of Practical Botany. Kathmandu (Ind):ArunKumar Ranjitkar.. Ratty Ak and Das NP. 1988. Effects of flavonoids onnonenzymatic lipid peroxidation: structure–activityrelationship. Biochem Med Metabol Biol.39(1):69–79 Winch T. 2006. Growing Food. Springer.1-103 Wu CP, Calcagno AM, Hladky SB, Ambudkar SV, and BarrandMA. 2005. Modulatory effects of plant phenols onhuman multidrug-resistance proteins 1, 4 and 5(ABCC1, 4 and 5). FEBS J.272(18):4725–4740.