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59-446: Sprouting or pre-harvest germination is caused by damp or rainy weather conditions during the final stage of maturation of the crop. The germination causes an accelerated production of the starch-degrading enzyme alpha-amylase . Severely sprouted grain kernels can contain several thousand times the amount of enzyme of sound un-sprouted kernels. Because of this, very low levels of severely sprouted kernels mixed into sound wheat can cause

118-426: A 100-gram ( 3 + 1 ⁄ 2 -ounce) reference serving, raw radishes provide 66 kilojoules (16 kilocalories) of food energy and have a moderate amount of vitamin C (18% of Daily Value ), with other essential nutrients in low content (table). A raw radish is 95% water, 3% carbohydrates , 1% protein , and has negligible fat . The most commonly eaten portion is the napiform or fusiform taproot , although

177-455: A parsnip . Sometimes referred to as European radishes or spring radishes if they are planted in cooler weather, summer radishes are generally small and have a relatively short three- to four-week cultivation time. 'Black Spanish' or 'Black Spanish Round' occur in both round and elongated forms, and are sometimes simply called the black radish (Raphanus sativus L. var. niger (M.) S.K. or L. ssp. niger (M.). D.C. var. albus D.C ) or known by

236-441: A petri dish or test tube). During germination, the tube cell elongates into a pollen tube . In the flower, the pollen tube then grows towards the ovule where it discharges the sperm produced in the pollen grain for fertilization. The germinated pollen grain with its two sperm cells is the mature male microgametophyte of these plants. Since most plants carry both male and female reproductive organs in their flowers, there

295-426: A species complex with the wild radish , and instead given the trinomial name Raphanus raphanistrum subsp. sativus . Radishes are often used raw as a crunchy salad vegetable with a pungent , slightly spicy flavor, varying in intensity depending on its growing environment. There are numerous varieties varying in size, flavor, color, and length of time they take to mature. Radishes owe their sharp flavor to

354-415: A trap crop , luring insect pests away from the main crop. Cucumbers and radishes seem to thrive when grown in close association with each other, and radishes also grow well with chervil , lettuce , peas , and nasturtiums . However, they react adversely to growing in close association with hyssop . As a fast-growing plant, diseases are not generally a problem with radishes, but some insect pests can be

413-565: A common garden crop in many parts of the world, and the fast harvest cycle makes them particularly suitable for children's gardens. After harvesting, radishes can be stored without loss of quality for two or three days at room temperature, and about two months at 0 °C (32 °F) with a relative humidity of 90–95%. Radishes can be useful as companion plants for many other crops, probably because their pungent odour deters such insect pests as aphids , cucumber beetles , tomato hornworms , squash bugs , and ants . They can also function as

472-788: A crunchy, sharp addition to salads. Some varieties are grown specifically for their seeds or seed pods, rather than their roots. The rat-tailed radish, an old European variety thought to have come from East Asia centuries ago, has long, thin, curly pods which can exceed 20 cm (8 in) in length. In the 17th century, the pods were often pickled and served with meat. The 'München Bier' variety supplies seed pods that are sometimes served raw as an accompaniment to beer in Germany . Using 2003–4 data, several sources report annual world production of radishes to be about 7 million tonnes , produced mainly by China , Japan , and South Korea , and representing roughly 2% of global vegetable production. In

531-473: A major hormone in the germination process. Another factor that promotes germination is HFR1 which accumulates in light in some way and forms inactive heterodimers with PIF1. Although the exact mechanism is not known, nitric oxide (NO) plays a role in this pathway as well. NO is thought to repress PIF1 gene expression and stabilises HFR1 in some way to support the start of germination. Bethke et al. (2006) exposed dormant Arabidopsis seeds to NO gas and within

590-494: A major role in integrating progression through germination with repair responses to the DNA damages accumulated by the aged seed. The part of the plant that first emerges from the seed is the embryonic root, termed the radicle or primary root. It allows the seedling to become anchored in the ground and start absorbing water. After the root absorbs water, an embryonic shoot emerges from the seed. This shoot comprises three main parts:

649-414: A nuisance. The larvae of flea beetles live in the soil, but the adult beetles cause damage to the crop, biting small "shot holes" in the leaves, especially of seedlings. The swede midge ( Contarinia nasturtii ) attacks the foliage and growing tip of the plant and causes distortion, multiple (or no) growing tips, and swollen or crinkled leaves and stems. The larvae of the cabbage root fly sometimes attack

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708-429: A plant hormone largely responsible for seed dormancy. The balance between GA and ABA is important. When ABA levels are higher than GA then that leads to dormant seeds and when GA levels are higher, seeds germinate. The switch between seed dormancy and germination needs to occur at a time when the seed has the best chances of surviving and an important cue that begins the process of seed germination and overall plant growth

767-459: A protective coat containing several cells (up to 8 in gymnosperms, 2–3 in flowering plants). One of these cells is a tube cell . Once the pollen grain lands on the stigma of a receptive flower (or a female cone in gymnosperms), it takes up water and germinates. Pollen germination is facilitated by hydration on the stigma, as well as by the structure and physiology of the stigma and style. Pollen can also be induced to germinate in vitro (in

826-510: A reduction in the mean germination time, an increase in the coefficient of germination velocity, the germination index and germination percentage after administration of exogenous glutamine to plants. Seed quality deteriorates with age, and this is associated with accumulation of genome damage. During germination, repair processes are activated to deal with accumulated DNA damage . In particular, single- and double-strand breaks in DNA can be repaired. The DNA damage checkpoint kinase ATM has

885-430: A spore-shedding adult plant. Bacterial spores can be exospores or endospores which are dormant structures produced by a number of different bacteria. They have no or very low metabolic activity and are formed in response to adverse environmental conditions. They allow survival and are not a form of reproduction. Under suitable conditions the spore germinates to produce a viable bacterium. Endospores are formed inside

944-465: A spread of 45 cm (18 in). The flesh of radishes harvested timely is crisp and sweet, but becomes bitter and tough if the vegetable is left in the ground too long. Leaves are arranged in a rosette . They have a lyrate shape, meaning they are divided pinnately with an enlarged terminal lobe and smaller lateral lobes. The white flowers are borne on a racemose inflorescence . The fruits are small pods which can be eaten when young. The radish

1003-440: A variety of ways. The leaves are sometimes used in recipes, like potato soup or as a sauteed side dish. They are also found blended with fruit juices in some recipes. In Indian cuisine the seed pods are called "moongra" or "mogri" and can be used in many dishes. The seeds of radishes can be pressed to extract radish seed oil . Wild radish seeds contain up to 48% oil, and while not suitable for human consumption, this oil

1062-423: A week or two apart. In warmer climates, radishes are normally planted in the autumn. The depth at which seeds are planted affects the size of the root, from 1 cm ( 1 ⁄ 2  in) deep recommended for small radishes to 4 cm ( 1 + 1 ⁄ 2  in) for large radishes. During the growing period, the crop needs to be thinned and weeds controlled, and irrigation may be required. Radishes are

1121-410: Is a diploid species, and has 18 chromosomes (2 n =18). It is estimated that the radish genome contains between 526 and 574 Mb . Radishes are a fast-growing, annual, cool-season crop. The seed germinates in three to four days in moist conditions with soil temperatures between 18 and 29 °C (65 and 85 °F). Best quality roots are obtained under moderate day lengths with air temperatures in

1180-432: Is a high risk of self-pollination and thus inbreeding . Some plants use the control of pollen germination as a way to prevent this self-pollination. Germination and growth of the pollen tube involve molecular signaling between stigma and pollen. In self-incompatibility in plants , the stigma of certain plants can molecularly recognize pollen from the same plant and prevent it from germinating. Germination can also refer to

1239-614: Is a hot-flavored variety which is typically grown to around 10 kg (22 lb), but which can grow to 30 kg (66 lb) when left in the ground. Korean radish , also called mu ( 무 ), is a variety of white radish with firm crunchy texture. Although mu is also a generic term for radishes in Korean (as daikon is a generic term for radishes in Japanese ), the word is usually used in its narrow sense, referring to Joseon radish( 조선무 , Joseonmu ). In Korean cuisine context,

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1298-688: Is a potential source of biofuel . The daikon grows well in cool climates and, apart from its industrial use, can be used as a cover crop, grown to increase soil fertility, to scavenge nutrients, suppress weeds, help alleviate soil compaction, and prevent winter erosion of the soil. "Radi", a spiral-cut radish, served with salt and occasionally chives, is traditionally served with beer at the Bavarian Oktoberfest . The daikon varieties of radish are important parts of East , Southeast , and South Asian cuisine. In Japan and Korea , radish dolls are sometimes made as children's toys. Daikon

1357-735: Is also one of the plants that make up the Japanese Festival of Seven Herbs ( Nanakusa no sekku ) on the seventh day after the new year. Citizens of Oaxaca , Mexico, celebrate the Night of the Radishes ( Noche de los rábanos ) on December 23 as a part of Christmas celebrations. This folk art competition uses a large type of radish up to 50 cm (20 in) long and weighing up to 3 kg (7 lb). Great skill and ingenuity are used to carve these into religious and popular figures, buildings, and other objects, and they are displayed in

1416-547: Is also sometimes called the Japanese radish, Chinese radish, Oriental radish or mooli (in India and South Asia ). Daikons commonly have elongated white roots, although many varieties of daikon exist. One well-known variety is 'April Cross', with smooth white roots. The New York Times describes 'Masato Red' and 'Masato Green' varieties as extremely long, well-suited for fall planting and winter storage. The Sakurajima radish

1475-448: Is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm , the growth of a sporeling from a spore , such as the spores of fungi , ferns, bacteria , and the growth of the pollen tube from the pollen grain of a seed plant . Germination is usually the growth of a plant contained within a seed resulting in the formation of the seedling. It is also the process of reactivation of metabolic machinery of

1534-423: Is as a cover or catch crop in winter, or as a forage crop. Some radishes are grown for their seeds; others, such as daikon, may be grown for oil production. Others are used for sprouting . Varieties of radish are now broadly distributed around the world, but almost no archeological records are available to help determine their early history and domestication. However, scientists have tentatively located

1593-470: Is light. Radish The radish ( Raphanus sativus ) is a flowering plant in the mustard family, Brassicaceae . Its large taproot is commonly used as a root vegetable , although the entire plant is edible and its leaves are sometimes used as a leaf vegetable . Originally domesticated in Asia , radishes are now grown and consumed throughout the world. The radish is sometimes considered to form

1652-401: Is the photoreceptor that is responsible for the beginning stages of germination. When red light is present, PHYB is converted to its active form and moves from the cytoplasm to the nucleus where it upregulates the degradation of PIF1 . PIF1, phytochrome-interaction-factor-1, negatively regulates germination by increasing the expression of proteins that repress the synthesis of gibberellin (GA),

1711-431: The cotyledons (seed leaves), the section of shoot below the cotyledons ( hypocotyl ), and the section of shoot above the cotyledons ( epicotyl ). The way the shoot emerges differs among plant groups. Epigeal germination (or epigeous germination) is a botanical term indicating that the germination takes place above the ground. In epigeal germination, the hypocotyl elongates and forms a hook, pulling rather than pushing

1770-418: The cotyledons and apical meristem through the soil. Once it reaches the surface, it straightens and pulls the cotyledons and shoot tip of the growing seedlings into the air. Beans , tamarind, and papaya are examples of plants that germinate this way. Germination can also be done by hypogeal germination (or hypogeous germination), where the epicotyl elongates and forms the hook. In this type of germination,

1829-600: The Cereal Laboratory of the Swedish Institute for the Crafts and Industries . The falling number method is uncomplicated, but requires an apparatus which follows the international standards. Such an apparatus consists of a water bath, a test tube, a stirring rod, and a stirring device. The test was performed manually when first employed, test instrumentation today is mostly automated. The speed at which

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1888-660: The French name Gros Noir d'Hiver . It dates in Europe to 1548, and was a common garden variety in England and France during the early 19th century. It has a rough, black skin with hot-flavored, white flesh, is round or irregularly pear shaped, and grows to around 10 cm (4 in) in diameter. Daikon refers to a wide variety of winter oilseed radishes from Asia. While the Japanese name daikon has been adopted in English, it

1947-753: The Jew noted that the radish, particularly its leaves, may be useful in traditional medicine to increase mucus. During the Middle Ages, Ibn Wahshiyya considered it a component of poison antidotes, while Maimonides highlighted its possible uses as a treatment. Al-Warraq's 10th century cookbook includes radish as a side dish for ostrich meat and an ingredient in a chicken dish called kardanāj . Radishes are annual or biennial brassicaceous crops grown for their swollen tap roots which can be globular, tapering, or cylindrical. The root skin colour ranges from white through pink, red, purple, yellow, and green to black, but

2006-442: The cotyledons stay underground where they eventually decompose. Peas, chickpeas and mango, for example, germinate this way. In monocot seeds, the embryo's radicle and cotyledon are covered by a coleorhiza and coleoptile , respectively. The coleorhiza is the first part to grow out of the seed, followed by the radicle. The coleoptile is then pushed up through the ground until it reaches the surface. There, it stops elongating and

2065-466: The emergence of cells from resting spores and the growth of sporeling hyphae or thalli from spores in fungi , algae and some plants. Conidia are asexual reproductive (reproduction without the fusing of gametes) spores of fungi which germinate under specific conditions. A variety of cells can be formed from the germinating conidia. The most common are germ tubes which grow and develop into hyphae. The initial formation and subsequent elongation of

2124-495: The entire lot to exhibit significant amylase activity. Since its introduction in the early 1960s, the FN test has become a world standard in the grain and flour milling industries for measuring alpha-amylase activity in wheat, durum wheat , triticale , rye and barley , as well as milled products made from these grains. The falling number method was developed at the end of the 1950s by Sven Hagberg and his co-worker Harald Perten, both at

2183-831: The entire plant is edible and the tops can be used as a leaf vegetable . The seed can also be sprouted and eaten raw in a similar way to a mung bean . The root of the radish is usually eaten raw, although tougher specimens can be steamed. The raw flesh has a crisp texture and a pungent, peppery flavor, caused by glucosinolates and the enzyme myrosinase , which combine when chewed to form allyl isothiocyanates , also present in mustard , horseradish , and wasabi . Radishes are mostly used in salads, but also appear in many European dishes. In Mexican cuisine , sliced radishes are used in combination with shredded lettuce as garnish for traditional dishes such as tostadas , sopes , enchiladas and pozole . Radish greens are usually discarded, but are edible and nutritious, and can be prepared in

2242-491: The establishment can be so high that many species have adapted to produce large numbers of seeds. In agriculture and gardening , the germination rate describes how many seeds of a particular plant species , variety or seedlot are likely to germinate over a given period. It is a measure of germination time course and is usually expressed as a percentage, e.g., an 85% germination rate indicates that about 85 out of 100 seeds will probably germinate under proper conditions over

2301-703: The first European crops introduced to the Americas . A German botanist reported radishes of 45 kilograms (100 pounds) and roughly 90 centimetres (3 feet) in length in 1544, although the only variety of that size today is the Japanese Sakurajima radish . The large, mild, and white East Asian form was developed in China , though it is mostly associated in the West with the Japanese daikon , owing to Japanese agricultural development and larger exports. Asaph

2360-509: The first leaves emerge. When a seed germinates without undergoing all four stages of seed development, i.e., globular, heart shape, torpedo shape, and cotyledonary stage, it is known as precocious germination. Another germination event during the life cycle of gymnosperms and flowering plants is the germination of a pollen grain after pollination . Like seeds, pollen grains are severely dehydrated before being released to facilitate their dispersal from one plant to another. They consist of

2419-615: The flesh is usually white. The roots obtain their color from anthocyanins . Red varieties use the anthocyanin pelargonidin as a pigment, and purple cultivars obtain their color from cyanidin . Smaller types have a few leaves about 13 cm (5 in) long with round roots up to 2.5 cm (1 in) in diameter or more slender, long roots up to 7 cm (3 in) long. Both of these are normally eaten raw in salads. A longer root form, including oriental radishes, daikon or mooli, and winter radishes, grows up to 60 cm (24 in) long with foliage about 60 cm (24 in) high with

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2478-404: The free-living amoebas of slime molds). In plants such as bryophytes , ferns , and a few others, spores germinate into independent gametophytes . In the bryophytes (e.g., mosses and liverworts ), spores germinate into protonemata , similar to fungal hyphae, from which the gametophyte grows. In ferns , the gametophytes are small, heart-shaped prothalli that can often be found underneath

2537-472: The germ tube in the fungus Aspergillus niger has been captured in 3D using holotomography microscopy. Another type of cell is a conidial anastomosis tube (CAT); these differ from germ tubes in that they are thinner, shorter, lack branches, exhibit determinate growth and home toward each other. Each cell is of a tubular shape, but the conidial anastomosis tube forms a bridge that allows fusion between conidia. In resting spores , germination involves cracking

2596-441: The germination period given. Seed germination rate is determined by the seed genetic composition, morphological features and environmental factors. The germination rate is useful for calculating the number of seeds needed for a given area or desired number of plants. For seed physiologists and seed scientists "germination rate" is the reciprocal of time taken for the process of germination to complete starting from time of sowing . On

2655-848: The individual seed variety and is closely linked to the ecological conditions of a plant's natural habitat . For some seeds, their future germination response is affected by environmental conditions during seed formation; most often these responses are types of seed dormancy . Most common annual vegetables have optimal germination temperatures between 75–90 F (24–32 C), though many species (e.g. radishes or spinach ) can germinate at significantly lower temperatures, as low as 40 F (4 C), thus allowing them to be grown from seeds in cooler climates. Suboptimal temperatures lead to lower success rates and longer germination periods. Some live seeds are dormant and need more time, and/or need to be subjected to specific environmental conditions before they will germinate. Seed dormancy can originate in different parts of

2714-540: The mother cell, whereas exospores are formed at the end of the mother cell as a bud. As mentioned earlier, light can be an environmental factor that stimulates the germination process. The seed needs to be able to determine when is the perfect time to germinate and they do that by sensing environmental cues. Once germination starts, the stored nutrients that have accumulated during maturation start to be digested which then supports cell expansion and overall growth. Within light-stimulated germination, phytochrome B ( PHYB )

2773-450: The next 4 days, 90% of the seeds broke dormancy and germinated. The authors also looked at how NO and GA effects the vacuolation process of aleurone cells that allow the movement of nutrients to be digested. A NO mutant resulted in inhibition of vacuolation but when GA was later added the process was active again leading to the belief that NO is prior to GA in the pathway. NO may also lead to the decrease in sensitivity of abscisic acid (ABA),

2832-545: The origin of Raphanus sativus in Southeast Asia , as this is the only region where truly wild forms have been discovered. India , central China , and Central Asia appear to have been secondary centers where differing forms were developed. Radishes enter the historical record in third century BC . Greek and Roman agriculturalists of the first century AD gave details of small, large, round, long, mild, and sharp varieties. The radish seems to have been one of

2891-610: The other hand, the number of seed able to complete germination in a population (i.e. seed lot) is referred to as germination capacity . Soil salinity is one of the stress factors that can limit the germination rate. Environmental stress activates some stress-related activities [CuZn- superoxide dismutase (SOD), Mn-SOD, L-ascorbate oxidase (AO), DNA polymerase Delta 1 (POLD)-1, Chaperon (CHAPE) and heat shock protein (HSP)-21], genetic template stability and photosynthetic pigment activation. Application of exogenic glutamine limiting this process. Research carried out on onion seeds shows

2950-527: The production of barley malt . In some definitions, the appearance of the radicle marks the end of germination and the beginning of "establishment", a period that utilizes the food reserves stored in the seed. Germination and establishment as an independent organism are critical phases in the life of a plant when they are the most vulnerable to injury, disease, and water stress. The germination index can be used as an indicator of phytotoxicity in soils. The mortality between dispersal of seeds and completion of

3009-512: The range 10 to 18 °C (50 to 65 °F). Under average conditions, the crop matures in 3–4 weeks, but in colder weather, 6–7 weeks may be required. Homegrown varieties can be significantly sharper. Radishes grow best in full sun in light, sandy loams , with a soil pH 6.5 to 7.0, but for late-season crops, a clayey-loam is ideal. Soils that bake dry and form a crust in dry weather are unsuitable and can impair germination. Harvesting periods can be extended by making repeat plantings, spaced

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3068-422: The roots. The foliage droops and becomes discoloured, and small, white maggots tunnel through the root, making it unattractive or inedible. Broadly speaking, radishes can be categorized into four main types according to the seasons when they are grown and a variety of shapes, lengths, colors, and sizes, such as red, pink, white, gray-black, or yellow radishes, with round or elongated roots that can grow longer than

3127-676: The seed begins to germinate and the embryo resumes growth, developing into a seedling. Disturbance of soil can result in vigorous plant growth by exposing seeds already in the soil to changes in environmental factors where germination may have previously been inhibited by depth of the seeds or soil that was too compact. This is often observed at gravesites after a burial. Seed germination depends on both internal and external conditions. The most important external factors include right temperature , water , oxygen or air and sometimes light or darkness . Various plants require different variables for successful seed germination. Often this depends on

3186-488: The seed resulting in the emergence of radicle and plumule . The seed of a vascular plant is a small package produced in a fruit or cone after the union of male and female reproductive cells . All fully developed seeds contain an embryo and, in most plant species some store of food reserves, wrapped in a seed coat. Dormant seeds are viable seeds that do not germinate because they require specific internal or environmental stimuli to resume growth. Under proper conditions,

3245-502: The seed, for example, within the embryo; in other cases the seed coat is involved. Dormancy breaking often involves changes in membranes, initiated by dormancy-breaking signals. This generally occurs only within hydrated seeds. Factors affecting seed dormancy include the presence of certain plant hormones, notably abscisic acid , which inhibits germination, and gibberellin , which ends seed dormancy. In brewing , barley seeds are treated with gibberellin to ensure uniform seed germination for

3304-417: The stirrer falls is determined by the viscosity of the slurry. Samples with more sprouted grain have greater alpha-amylase activity, which will result in a less viscous slurry and a greater falling number. Samples with less alpha-amylase activity will be more viscous and have a lesser falling number. Germination Germination is the process by which an organism grows from a seed or spore . The term

3363-439: The thick cell wall of the dormant spore. For example, in zygomycetes the thick-walled zygosporangium cracks open and the zygospore inside gives rise to the emerging sporangiophore. In slime molds , germination refers to the emergence of amoeboid cells from the hardened spore. After cracking the spore coat, further development involves cell division, but not necessarily the development of a multicellular organism (for example in

3422-490: The various chemical compounds produced by the plants, including glucosinolate , myrosinase , and isothiocyanate . They are sometimes grown as companion plants and suffer from few pests and diseases. They germinate quickly and grow rapidly, common smaller varieties being ready for consumption within a month, while larger daikon varieties take several weeks. Being relatively easy to grow and quick to harvest, radishes are often planted by novice gardeners. Another use of radish

3481-804: The word Joseon is often used in contrast to Wae , to distinguish Korean varieties from Japanese ones. The longer, thinner, and waterier Japanese daikon cultivated mainly for danmuji is referred to as Wae radish( 왜무 , Waemu ) in Korea. Korean radishes are generally shorter, stouter, and sturdier than daikon, and have pale green shade halfway down from the top. They also have stronger flavour, denser flesh and softer leaves. The greens of Korean radishes are called mucheong ( 무청 ) and used as vegetable in various dishes. The seeds of radishes grow in siliques (widely referred to as "pods"), following flowering that happens when left to grow past their normal harvesting period. The seeds are edible, and are sometimes used as

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