(redirected from beta-adrenergic receptors)
Also found in: Dictionary, Thesaurus, Medical, Legal, Financial.


1. the second letter in the Greek alphabet (Β or β), a consonant, transliterated as b
a. involving or relating to electrons
b. relating to one of two or more allotropes or crystal structures of a solid
c. relating to one of two or more isomeric forms of a chemical compound


(bay -tă, bee -) (β) The second letter of the Greek alphabet, used in stellar nomenclature usually to designate the second-brightest star in a constellation or sometimes to indicate a star's position in a group.



(beets), a genus of annual, biennial, and perennial plants of the family Chenopodiaceae. There are 13 species, of which 11 are wild and two are cultivated. The five species found in the USSR include the two cultivated species.

Wild species include B. procumbens, B. macrorhiza, B. lomatogona, B. intermedia, B. trigyna, B. maritima, and B. patula. Wild beets grow in the Mediterranean Region, the Middle East, Transcaucasia, the Crimea, and the Balkans. They are distributed as far east as India and as far west as France, Great Britain, and Scandinavia.

The two cultivated species, Swiss chard (B. cicla) and the common beet (B. vulgaris), are biennials. The latter species is divided into European and Asian subspecies. The European subspecies include varieties of garden, feed, and sugar beets. The Asian subspecies include predominantly inferior varieties with weakly developed roots. Numerous varieties of cultivated beets have been developed by breeding.

The flower-bearing stem, which is grassy, erect, and very heavily branched, appears in biennial and perennial species in the second season. The large, smooth or wavy leaves are triangular, lingulate, or cordate. The basal leaves have long petioles, and upper leaves are short-petioled and almost sessile. The bisexual green or whitish flowers have a pentamerous cup-shaped perianth, five stamens, and one pistil; they are gathered into long leafy inflorescences and often are in sessile groups. The plants are cross-pollinated by small insects. The kidney-shaped fruits grow together as they mature, forming clusters of two to six. The seeds are enclosed in a shell. The first sugar beet with a one-seeded fruit cluster, or seedball, was developed in the USSR. The spindle-shaped root of wild beets and leaf beets becomes woody and is entirely underground. The common garden beet has a fleshy, succulent root, which emerges to the soil surface in most varieties.

The wild beet has been used as food since prehistoric times. In the first or second millennium B.C. the chard was brought under cultivation, presumably on islands in the Mediterranean Sea, as a medicinal and vegetable plant. Cultivated forms of the common beet appeared by the beginning of the Common Era. They were known in Kievan Rus’ in the tenth or 11th century and in Western Europe in the 13th or 14th century. The differentiation of the common beet into garden and feed varieties occurred in the 16th or 17th century. The sugar beet was isolated from hybrid forms of feed beets in the 18th century. Since the late 19th and early 20th centuries beet cultivation has spread to all continents.

The garden beet, also called table beet or red beet, forms during the first season an oblate-spherical, ovate-spherical, or flattened tuber, weighing 0.4–0.9 kg, and a top of red-veined green or red leaves. The tuber, which has dark red, claret, or red violet flesh, contains 13–20 percent dry matter, including 9–16 percent sugar, 1.8–3 percent protein, up to 0.5 percent organic acid, 0.7–1.4 percent cellulose, and 0.8–1.3 percent mineral salts. It also contains vitamins C, B, P, and PP. The tubers and the young plants are used as food.

Garden beets are raised on all continents. They are cultivated in all the agricultural zones of the USSR: in 1973 garden beets occupied roughly 50,000 hectares (ha) and yielded 400–500 quintals per ha (maximum, 1,000 quintals). In 1974 there were 21 regionalized varieties; the best included Bordeaux 237, Nesravnennaia A-463, Gribovskaia ploskaia A-473, and Podzimniaia A-474.

Garden beets are planted in rotation with cabbage, tomatoes, and cucumbers. At least 30 tons/ha of humus are applied during autumn plowing; on acid soils 5–10 tons/ha of lime are also applied. The beets are sown in the spring or autumn in double rows or with wide spacing between rows (33 cm). The rate of sowing is 16–20 kg/ha, with the seeds placed at a depth of 2–3 cm. Crop management involves the use of herbicides (spraying with pyramine), thinning twice, topdressing, soil loosening, and watering (in hot summers and in regions of irrigation farming). The tubers are gathered by beet pullers and, after leaf removal, are stored in root cellars.

In the first season the feed beet, which is commonly called the mangel-wurzel, forms a large tuber, weighing up to 10–12 kg and varying in shape (saclike, oval-conical, cylindrical, spherical) and color (yellow, white, red). Its green top leaves are used as succulent feed, including silage. One hundred kilograms of tubers contain 12.2 feed units and 0.9 kg of digestible protein, 100 kg of leaves contain 10.2 feed units and 1.8 kg of digestible protein. Mangel-wurzels have been raised in what is now the USSR since the 18th century. They are cultivated (1973) in many European countries, the United States, Canada, Brazil. Australia, New Zealand, Algeria, Tunisia, and elsewhere.

In the USSR mangel-wurzels occupied roughly 800,000 ha in 1973; the average yield of tubers was 300–400 quintals per ha. The primary regions of cultivation are the Ukrainian Poles’e, the central regions of the nonchernozem zone of. the RSFSR, the Volga Region, Byelorussia, and Lithuania. As of 1974 there were 25 regionalized varieties; the best included Ekkendorfskaia Zheltaia, Arnim krivenskaia, Barres, Pobeditel’, and Polusakharnaia Belaia. Certain varieties of sugar beets, for example, Sakharnaia Okruglaia 143, are also raised for feed. In feed crop rotation, mangel-wurzels are planted after annual green fodder mixtures, potatoes, and silage corn. Fertilizer dosages are 30–40 tons/ha of organic fertilizer and 60–120 kg/ha of NPK. The beets are planted in wide rows and single-drill rows 45–60 cm apart, with a sowing rate of 15–25 kg and 8–12 kg of seed per ha, respectively. The seed is sown at depths of 2.5–4 cm. Crop management is similar to that for garden beets. Feed beets are harvested by potato pickers, potato-harvesting combines, and beet pullers. They are stored in piles or root cellars.

During the first season the sugar beet develops an elongated, sugar-rich (up to 23 percent) tuber, which weighs an average of 300–600 g. It has white flesh and a top of light green leaves. The growing season is 100 to 170 days in the first year and 100 to 125 days in the second year. The sugar beet deviates more from the two-year cycle of development than other forms of beets with respect to flowering in the first season and not flowering in the second. These attributes are related to varietal characteristics and conditions of cultivation and storage of the tubers. The sugar beet thrives on heat, light, and moisture, although it also has comparatively high drought and salt resistance. The optimum temperature for seed germination is 10°-12°C; the optimum temperature for growth and development is 20°-22°C. The sprouts are sensitive to frost and die at a temperature of – 4° or – 5°C. The sugar content of the tubers depends on the number of sunny days between August and October. The plant consumes the greatest amount of moisture in July and August—the period of intensive tuber growth. The sugar beet is particularly productive on chernozems.

The sugar beet is an important industrial crop; it provides raw material for the sugar industry. By-products include pulp residue (used for livestock feed), molasses (a food product), and defecation slime (a lime fertilizer). In 1747 the German chemist A. S. Marggraf proposed that beets with white tubers could expediently be used to obtain crystalline sugar. Later in the century his countryman F. C. Achard selected and bred beets with increased sucrose content and obtained large amounts of beet sugar at his factory. The scientific selection of sugar beets was begun in the mid- 19th century in France by L. Vilmorin.

In 1900 sugar beets were planted on 497,500 ha in Russia; in 1913 the figure had risen to 676,000 ha, with an average yield of 168 quintals per ha. The industrial characteristics of the raw material were improved through selection work, better seed-raising, and improved cultivation. In 1811 the sugar content of the beets was no greater than 6–7 percent; by 1908 the sugar content had been increased to an average of 18.5 percent.

Since 1900 sugar beets have been raised primarily in countries with temperate climates. For statistics on world sugar beet production see Table 1.

In 1973 the highest sugar beet yields in the USSR were obtained in Kirghizia (387 quintals/ha), Georgia (331 quintals/ha), and the Ukraine (279 quintals/ha). The principal areas of cultivation are the Ukraine, the central chernozem regions, the Northern Caucasus, Moldavia, Kazakhstan, and Kirghizia. Domestically bred varieties and hybrids exclusively are planted in the USSR. In 1974, 30 varieties (including six one-seeded varieties) and ten hybrids (seven one-seeded hybrids) were regionalized. They comprised heavy-producing (sugar content 17.9–18.3 percent; yield 48–51 quintals/ha), high-sugar (sugar content 18.7–19 percent; yield 43–44 quintals/ha), and combination heavy-producing and high-sugar (sugar content 18.5–18.7 percent; yield 47–49 quintals/ha) varieties and hybrids. The best are Ramonskaia 06, Ramonskaia 100, Ialtushkovskaia Odnosemiannaia. Ialtushkovskii hybrid, and Belotserkovskii Polyhybrid 1 and 2. In 1974, one-seeded varieties constituted 60 percent of the sugar beet plantings of the USSR (75 percent in the Ukraine). The goal of selection in the USSR is to breed highly productive varieties and hybrids (including one-seeded polyhybrids), which have excellent industrial characteristics and which are disease and pest resistant, responsive to large doses of fertilizer and to irrigation (for irrigation regions), fast-maturing, and nonflowering in the first season.

In crop rotation, sugar beets are usually planted after winter wheat followed by perennial grasses and bare and occupied fallow. The primary soil tillage involves scuffling stubble and deep (28–32 cm) autumn plowing. Approximate fertilizer norms are 20–30 tons/ha of manure, 30–60 kg/ha of N, 30–90 kg/ha of P2O5, and 45–60 kg/ha of K2O. It is most efficient to apply fertilizer in the drills with the seeds and as topdressing. Sugar beets are planted by the wide-row and single-seed methods, with interrow spaces of 45–60 cm. The seeds, which have been graded by size, treated, and coated, are sown at a rate of 10–28 kg/ha at depths of 2–5 cm. Field management involves pregermination and postgermination harrowing, blocking and subsequent thinning out, loosening the interrow soils, topdressing, and watering (in Kirghizia, Kazakhstan, and other regions with inadequate moisture).

The plants are harvested when they have reached the greatest sugar content in the tubers. The tubers are stored in underground and surface pits. Full mechanization of sugar beet cultivation in the principal beet-growing regions of the USSR involves special machinery (sugar-beet drills, thinning machines, cultivator-feeders), in addition to general-purpose machinery and implements. Sugar beets are gathered primarily by beet-harvesting combines, which use either the continuous or two-stage method. With the first method, the beets are transported from the combine to a processing plant or storage area. The two-stage method involves dumping the beets from the combine into piles at the edge of the field or some special area and then loading them onto a transport vehicle. In swath harvesting two combines work in the field simultaneously; the first cuts the tops and the second digs up the tubers. On small and uneven plots, sugar beets are harvested by beet pullers. Sugar beet pests include the flea beetle, the beet weevil, the beet leaf miner, the sugar-beet root aphid, and the beet bug. Diseases include black root, cercosporosis, nematode diseases, powdery mildew, and leaf mosaic.

Table 1. World sugar beet production
 Sown area (million ha)Gross tuber harvest (million tons)Yield (quintals/ha)
1Sugar beet plantings occupy very small areas in Asia and Africa, and the crop is not raised in Australia
Source: Un Food and Agriculture Organization, 1972
 Poland ....................0.430.410.4211.4412.7414.30267.0312.3332.6
 France ....................0.380.410.4414.3917.4418.67378.2426.1421.0
 Federal Republic of Germany......0.300.300.3311.1913.4614.66378.8444.4442.8
 Czechoslovakia ..............
 Italy ......................
 German Democratic Republic......

In the USSR sugar beet seeds are raised by selection-testing stations (where varieties are developed), special elite seed-growing sovkhozes, and regular seed-growing sovkhozes. The last raise the seeds that are used in agriculture.


Krasochkin, V. T. Svekla. Moscow-Leningrad, 1960.
Karpenko, P. V. Sveklovodstvo, 3rd ed. Moscow, 1964.
Sortoopisanie ovoshchnykh bakhchevykh kul’tur i kormovykh korneplodov. Moscow, 1965.
Biologiia i selektsiia sakharnoi svekly. Moscow, 1968.
Kul’turnaia flora SSSR, vol. 19: Korneplodnye rasteniia. Leningrad, 1971.



For dust grains ejected from the nucleus of a comet, the ratio of the radiation pressure force to the solar gravitational force.
The current gain of a transistor that is connected as a grounded-emitter amplifier, expressed as the ratio of change in collector current to resulting change in base current, the collector voltage being constant.
The amount of reactivity of a nuclear reactor corresponding to the delayed neutron fraction.
(plasma physics)
The ratio of the ion energy density of a plasma to its magnetic energy diversity, or of the particle pressure to the magnetic-field pressure.
(science and technology)
The second letter of the Greek alphabet; β, B.


Kristensen, Madsen <>, Moller-Pedersen & Nygaard, 1983. Object-oriented language with block structure, coroutines, concurrency, strong typing, part objects, separate objects and classless objects. Central feature is a single abstraction mechanism called "patterns", a generalisation of classes, providing instantiation and hierarchical inheritance for all objects including procedures and processes.

Mjolner Informatics ApS, Aarhus, implementations for Mac, Sun, HP, Apollo.

E-mail: <>.

Mailing list: <>.

["Object-Oriented Programming in the BETA Programming Language", Ole Lehrmann et al, A-W June 1993, ISBN 0-201-62430-3].


/bay't*/, /be't*/ or (Commonwealth) /bee't*/

See beta conversion, beta test.
References in periodicals archive ?
1977) Hydrodynamic properties of the beta-adrenergic receptor and adenylate cyclase from wild type and varient S49 lymphoma cells.
beta-Adrenergic receptor polymorphisms and responses during titration of metoprolol controlled release/ extended release in heart failure.
Use of a left ventricular assist device (LVAD) reverses the down regulation of beta-adrenergic receptors that is characteristic of heart failure, according to an autopsy study reported in the August 21 issue of Circulation.
In prior presentations, Cytokinetics scientists presented results that demonstrate that cardiac myosin activators increase cardiac contractility without increasing intracellular calcium and without stimulating beta-adrenergic receptors or inhibiting phosphodiesterase activity, mechanisms that may be arrhythmogenic and associated with other adverse clinical effects.
Patients with heart disease usually have higher levels of catecholamines - hormones that activate the beta-adrenergic receptors to stimulate cardiac muscle contraction.

Full browser ?