CC BY
13УДК 631
Shohumova Sh.
Junior scientific Production and scientific agricultural of the department grapes cultural and fruit gardening of the center (Ashgabat, Turkmenistan)
Yusupgulyev H.
Turkmen Agricultural University named after S. Niyazov (Ashgabat, Turkmenistan)
Tahyrowa O.
Turkmen Agricultural University named after S. Niyazov (Ashgabat, Turkmenistan)
ON THE ORIGIN AND DOMESTICATION HISTORY OF BARLEY (HORDEUM VULGARE)
Abstract: barley (Hordeum vulgare), a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains, particularly in Eurasia as early as 10,000 years ago.[2] Globally 70% of barley production is used as animal fodder,[3] while 30% as a source of fermentable material for beer and certain distilled beverages, and as a component of various foods. It is used in soups and stews, and in barley bread of various cultures. Barley grains are commonly made into malt in a traditional and ancient method of preparation.
In 2017, barley was rankedfourth among grains in quantity produced (149 million tonnes or 330 billion pounds) behind maize (corn), rice and wheat.[4]
Keywords: fermentable material, various cultures, ancient method.
Introduction.
Barley is a member of the grass family. It is a self-pollinating, diploid species with 14 chromosomes. The wild ancestor of domesticated barley, Hordeum vulgare subsp. spontaneum, is abundant in grasslands and woodlands throughout the Fertile Crescent area of Western Asia and northeast Africa, and is abundant in disturbed habitats, roadsides, and orchards. Outside this region, the wild barley is less common and is usually found in disturbed habitats. [2] However, in a study of genome-wide diversity markers, Tibet was found to be an additional center of domestication of cultivated barley.[9]
Wild barley (H. spontaneum) is the ancestor of domestic barley (H. vulgare). Over the course of domestication, barley grain morphology changed substantially, moving from an elongated shape to a more rounded spherical one.[10] Additionally, wild barley has distinctive genes, alleles, and regulators with potential for resistance to abiotic or biotic stresses to cultivated barley and adaptation to climatic changes.[11] Wild barley has a brittle spike; upon maturity, the spikelets separate, facilitating seed dispersal. Domesticated barley has nonshattering spikes, making it much easier to harvest the mature ears.[2] The nonshattering condition is caused by a mutation in one of two tightly linked genes known as Bt1 and Bt2; many cultivars possess both mutations. The nonshattering condition is recessive, so varieties of barley that exhibit this condition are homozygous for the mutant allele.[2] Domestication in barley is followed by the change of key phenotypic traits at the genetic level. Little is known about the genetic variation among domesticated and wild genes in the chromosomal regions. [12]
Spikelets are arranged in triplets which alternate along the rachis. In wild barley (and other Old World species of Hordeum), only the central spikelet is fertile, while the other two are reduced. This condition is retained in certain cultivars known as two-row barleys. A pair of mutations (one dominant, the other recessive) result in fertile lateral spikelets to produce six-row barleys.[2] Recent genetic studies have revealed that a mutation in one gene, vrs1, is responsible for the transition from two-row to six-row barley.[13]
Two-row barley, sometimes considered a separate species, H. distichon, has a lower protein content than six-row barley, thus a more fermentable sugar content. High-protein barley is best suited for animal feed. Malting barley is usually lower protein[14] ("low grain nitrogen", usually produced without a late fertilizer application) which shows more uniform germination, needs shorter steeping, and has less protein in the extract that can make beer cloudy. Two-row barley is traditionally used in English ale-style beers, with two-row malted summer barley being preferred for traditional German beers.[citation needed]
Amylase-rich six-row barley is common in some American lager-style beers, especially when adjuncts such as corn and rice are used.[citation needed]
H. vulgare contains the phenolics caffeic acid and p-coumaric acid, the ferulic acid 8,5'-diferulic acid, the flavonoids catechin-7-O-
glucoside,[27] saponarin,[28] catechin, procyanidin B3, procyanidin C2, and prodelphinidin B3, and the alkaloid hordenine.
Barley is often assessed by its malting enzyme content.[29] Barley is a widely adaptable crop. It is currently popular in temperate areas where it is grown as a summer crop and tropical areas where it is sown as a winter crop. Its germination time is one to three days. Barley grows under cool conditions, but is not particularly winter hardy.[citation needed]
Barley is more tolerant of soil salinity than wheat, which might explain the increase of barley cultivation in Mesopotamia from the second millennium BCE onwards. Barley is not as cold tolerant as the winter wheats (Triticum aestivum), fall rye (Secale cereale) or winter triticale (* Triticosecale Wittm. ex A. Camus.), but may be sown as a winter crop in warmer areas of Australia and Great Britain.
Barley has a short growing season and is also relatively drought tolerant. [48]
REFERENCES:
1. Domestication of Plants in the Old World: The Origin and Spread of Cultivated Plants in West Asia, Europe, and the Nile Valley (3rd ed.). Oxford University Press. pp. 59-69. ISBN 978-0-19-850357-6.
2. Food and Agriculture Organization of the United Nations. "BARLEY: Post-Harvest Operations" (PDF).
3. Production Quantity for Barley, 2017 (pick list)". Food and Agriculture Organization Corporate Statistical Database. 2018. Retrieved 8 September 2018.
