Чайный куст китайский Camellia Sinensis зелёный, чёрный и другие виды

Referencesedit

  1. ^
  2. .
  3. .
  4. .
  5. Wambulwa, MC, MK Meegahakumbura, R Chalo, et al. 2016. Nuclear microsatellites reveal the genetic architecture and breeding history of tea germplasm of East Africa. Tree Genetics & Genomes, 12.
  6. Yamamoto, T; Kim, M; Juneja, L R (1997). Chemistry and Applications of Green Tea. CRC Press. p. 4. ISBN 978-0-8493-4006-2. For a long time, botanists have asserted the dualism of tea origin from their observations that there exist distinct differences in the morphological characteristics between Assamese varieties and Chinese varieties… Hashimoto and Shimura reported that the differences in the morphological characteristics in tea plants are not necessarily the evidence of the dualism hypothesis from the researches using the statistical cluster analysis method. In recent investigations, it has also been made clear that both varieties have the same chromosome number (n=15) and can be easily hybridised with each other. In addition, various types of intermediate hybrids or spontaneous polyploids of tea plants have been found in a wide area extending over the regions mentioned above. These facts may prove that the place of origin of Camellia sinensis is in the area including the northern part of the Burma, Yunnan, and Sichuan districts of China.
  7. ^
  8. ^
  9. Wambulwa, MC, MK Meegahakumbura, R Chalo, et al. 2016. Nuclear microsatellites reveal the genetic architecture and breeding history of tea germplasm of East Africa. Tree Genetics & Genomes, 12.
  10. ^
  11. ^
  12. .
  13. .
  14. ^
  15. Ming TL (1992). “A revision of Camellia sect. Thea”. Acta Botanica Yunnanica (in Chinese). 14 (2): 115–32..
  16. ^
  17. Pizzorno JE, Murray MT, eds. (2012). Textbook of Natural Medicine (4th ed.). Edinburgh: Churchill Livingstone. p. 628. ISBN 978-1-4377-2333-5.

Referencesedit

  1. ^
  2. .
  3. .
  4. .
  5. Wambulwa, MC, MK Meegahakumbura, R Chalo, et al. 2016. Nuclear microsatellites reveal the genetic architecture and breeding history of tea germplasm of East Africa. Tree Genetics & Genomes, 12.
  6. Yamamoto, T; Kim, M; Juneja, L R (1997). Chemistry and Applications of Green Tea. CRC Press. p. 4. ISBN 978-0-8493-4006-2. For a long time, botanists have asserted the dualism of tea origin from their observations that there exist distinct differences in the morphological characteristics between Assamese varieties and Chinese varieties… Hashimoto and Shimura reported that the differences in the morphological characteristics in tea plants are not necessarily the evidence of the dualism hypothesis from the researches using the statistical cluster analysis method. In recent investigations, it has also been made clear that both varieties have the same chromosome number (n=15) and can be easily hybridised with each other. In addition, various types of intermediate hybrids or spontaneous polyploids of tea plants have been found in a wide area extending over the regions mentioned above. These facts may prove that the place of origin of Camellia sinensis is in the area including the northern part of the Burma, Yunnan, and Sichuan districts of China.
  7. ^
  8. ^
  9. Wambulwa, MC, MK Meegahakumbura, R Chalo, et al. 2016. Nuclear microsatellites reveal the genetic architecture and breeding history of tea germplasm of East Africa. Tree Genetics & Genomes, 12.
  10. ^
  11. ^
  12. .
  13. .
  14. ^
  15. Ming TL (1992). “A revision of Camellia sect. Thea”. Acta Botanica Yunnanica (in Chinese). 14 (2): 115–32..
  16. ^
  17. Pizzorno JE, Murray MT, eds. (2012). Textbook of Natural Medicine (4th ed.). Edinburgh: Churchill Livingstone. p. 628. ISBN 978-1-4377-2333-5.

Химический состав

Листья чайного куста содержат алкалоиды: кофеин (2-5% от сухой массы), теофиллин, теобромин, ксантин, аденин, гиноксантин, параксантин, метилксаптин, изатин, 9-35% дубильных веществ, среди них 26% растворимых и до 9,8% нераство¬римых. Некоторые дубильные вещества находятся в связанном с протеинами и алкалоидами состоянии. В листьях чая также обнаружены лецитин, нуклеотидаденин и содержащие железо и марганец нуклеопротеиды, а также витамины С, В, К, РР, пантотеновая кислота, эфирное масло. В стеблях, корнях и семенах растения содержатся сапонины, причем наибольшее их количество обнаружено в семенах (9— 10%). В семенах чая найдено 22-35% жирного масла, 32,5% крахмала, 8,5% белка. По содержанию витамина Р чай не имеет себе равных. При ежедневном употреблении 3/4 стакана зеленого чая хорошей крепости организм обеспечивается суточной профилактической дозой витамина Р. Витамина С много в зеленом чае, а в черном — в 10 раз меньше. Поэтому очень оправданно добавление в черный чай лимона или клюквы, т. к. витамины Р и С особенно хорошо действуют не порознь, а вместе.

Мята

Это самое популярное и полезное растение для чая. Мяту можно вырастить не только на огороде, но и на подоконнике.

Чайный куст китайский Camellia Sinensis зелёный, чёрный и другие видыНа фото цветущая мята

Всего несколько листочков мяты достаточно для приготовления освежающего, вкусного и ароматного напитка, который к тому же имеет множество полезных свойств:

  • прекрасно утоляет жажду;
  • успокаивает нервную систему;
  • повышает настроение;
  • избавляет от чувства тревоги;
  • нормализует гормональный фон;
  • уменьшает газообразование в кишечнике;
  • даёт мягкий отток желчи;

Противопоказанием к употреблению чая является индивидуальная непереносимость, низкое артериальное давление, беременность и кормление грудью. Регулярное употребление мятного чая снижает мужское либидо.

Описание, размножение и ареал распространения чайного куста

Многолетний вечнозеленый кустарник высотой до 10 метров стоящими ветвями, семейства чайных.

На плантациях чайный куст — невысокий (1 м).

Листья чайного куста очередные, овальные или удлиненно- овальные, короткочерешковые, кожистые, гладкие, сверху темно-зеленые, снизу светло-зеленые.

Цветки белые, с желтовато-розовым оттенком, одиночные или по 2-4 вместе в пазухах листьев.

Плод — трехстворчатая деревянистая коробочка.

Семена округлые, темно-коричневые, диаметром 10-13 мм.

Цветет с августа до поздней осени. Плодоносит в октябре—декабре.

На территории России чай культивируется во влажных субтропиках, в Краснодарском крае.

Cultivationedit

C. sinensis is mainly cultivated in tropical and subtropical climates, in areas with at least 127 cm (50 in) of rainfall a year. Tea plants prefer a rich and moist growing location in full to part sun, and can be grown in hardiness zones 7 – 9. However, the clonal one is commercially cultivated from the equator to as far north as Cornwall and Scotland on the UK mainland. Many high quality teas are grown at high elevations, up to 1,500 m (4,900 ft), as the plants grow more slowly and acquire more flavour.

Tea plants will grow into a tree if left undisturbed, but cultivated plants are pruned to waist height for ease of plucking. Two principal varieties are used, the small-leaved Chinese variety plant (C. s. sinensis) and the large-leaved Assamese plant (C. s. assamica), used mainly for black tea.

Chinese teasedit

The Chinese plant is a small-leafed bush with multiple stems that reaches a height of some 3 m. It is native to southeast China. The first tea plant variety to be discovered, recorded, and used to produce tea dates back 3,000 years ago, it yields some of the most popular teas.

C. s. var. waldenae was considered a different species, C. waldenae by SY Hu, but it was later identified as a variety of C. sinensis. This variety is commonly called Waldenae Camellia. It is seen on Sunset Peak and Tai Mo Shan in Hong Kong. It is also distributed in Guangxi province, China.

Indian and Nepali teasedit

Three main kinds of tea are produced in India:

  • Assam comes from the heavily forested northeastern section of the country, Assam. Tea from here is rich and full-bodied. In Assam, the first tea estate of India was established, in 1837.
  • Darjeeling is from the cool and wet Darjeeling region, tucked in the foothills of the Himalayas. Tea plantations reach 2,200 metres. The tea is delicately flavoured, and considered to be one of the finest teas in the world. The Darjeeling plantations have three distinct harvests, termed ‘flushes’, and the tea produced from each flush has a unique flavour. First (spring) flush teas are light and aromatic, while the second (summer) flush produces tea with a bit more bite. The third, or autumn flush gives a tea that is lesser in quality.

Nepali tea is also considered to be similar to the tea produced in Darjeeling, mostly because the eastern part of Nepal, where a large amount of tea is produced, has similar topography to that of Darjeeling.

Nilgiri is from a southern region of India almost as high as Darjeeling. Grown at elevations between 1,000 and 2,500 m, Nilgiri teas are subtle and rather gentle, and are frequently blended with other, more robust teas.

Seed-bearing fruit of C. sinensis

Pests and diseasesedit

Tea leaves are eaten by some herbivores, such as the caterpillars of the willow beauty (Peribatodes rhomboidaria), a geometer moth.

Biosynthesis of caffeineedit

Caffeine, a molecule produced in C. sinensis, functions as a secondary metabolite. Caffeine is a purine alkaloid and its biosynthesis occurs in young tea leaves and is regulated by several enzymes. The biosynthetic pathway in C. sinensis differs from other caffeine-producing plants such as coffee or guayusa. Analysis of the pathway was carried out by harvesting young leaves and using reverse transcription PCR to analyze the genes encoding the major enzymes involved in synthesizing caffeine. The gene TCS1 encodes caffeine synthase. Younger leaves feature high concentrations of TCS1 transcripts, allowing more caffeine to be synthesized during this time. Dephosphorylation of xanthosine-5′-monophosphate into xanthosine is the committed step for the xanthosines entering the beginning of the most common pathway. A sequence of reactions turns xanthosine into 7-methylxanthosine, then 7-methylxanthine, then theobromine, and finally into caffeine.

Biochemical pathway detailing caffeine synthesis in C. sinensis

Nomenclature and taxonomyedit

The generic name Camellia is taken from the Latinized name of Rev. Georg Kamel,SJ (1661–1706), a Moravian-born Jesuit lay brother, pharmacist, and missionary to the Philippines.

Carl Linnaeus chose his name in 1753 for the genus to honor Kamel’s contributions to botany (although Kamel did not discover or name this plant, or any Camellia, and Linnaeus did not consider this plant a Camellia but a Thea).

Robert Sweet shifted all formerly Thea species to the genus Camellia in 1818. The name sinensis means “from China” in Latin.

Four varieties of C. sinensis are recognized. Of these, C. sinensis var. sinensis and C. s. var. assamica (JW Masters) Kitamura are most commonly used for tea, and C. s. var. pubilimba Hung T. Chang and C. s. var. dehungensis (Hung T. Chang & BH Chen) TL Ming are sometimes used locally. The Cambod type tea (C. assamica subsp. lasiocaly) was originally considered a type of assam tea. However, later genetic work showed that it is a hybrid between Chinese small leaf tea and assam type tea.

Tea plants are native to East Asia, and probably originated in the borderlands of north Burma and southwestern China.

  • Chinese (small leaf) tea [C. sinensis var. sinensis]
  • Chinese Western Yunnan Assam (large leaf) tea [C. sinensis var. assamica

    Indian Assam (large leaf) tea

    ]

  • Chinese Southern Yunnan Assam (large leaf) tea [C. sinensis var. assamica]

Chinese (small leaf) type tea may have originated in southern China possibly with hybridization of unknown wild tea relatives. However, since no wild populations of this tea are known, the precise location of its origin is speculative.

Given their genetic differences forming distinct clades, Chinese Assam type tea (C. s. var. assamica) may have two different parentages – one being found in southern Yunnan (Xishuangbanna, Pu’er City) and the other in western Yunnan (Lincang, Baoshan). Many types of Southern Yunnan Assam tea have been hybridized with the closely related species Camellia taliensis. Unlike Southern Yunnan Assam tea, Western Yunnan Assam tea shares many genetic similarities with Indian Assam type tea (also C. s. var. assamica). Thus, Western Yunnan Assam tea and Indian Assam tea both may have originated from the same parent plant in the area where southwestern China, Indo-Burma, and Tibet meet. However, as the Indian Assam tea shares no haplotypes with Western Yunnan Assam tea, Indian Assam tea is likely to have originated from an independent domestication. Some Indian Assam tea appears to have hybridized with the species Camellia pubicosta.

Assuming a generation of 12 years, Chinese small leaf tea is estimated to have diverged from Assam tea around 22,000 years ago, while Chinese Assam tea and Indian Assam tea diverged 2,800 years ago. This divergence tea would correspond to the last glacial maximum.

Chinese small leaf type tea was introduced into India in 1836 by the British and some Indian Assam type tea (e.g. Darjeeling tea) appear to be genetic hybrids of Chinese small leaf type tea, native Indian Assam, and possibly also closely related wild tea species.

Descriptionedit

C. sinensis is native to East Asia, the Indian Subcontinent, and Southeast Asia, but it is today cultivated across the world in tropical and subtropical regions. It is an evergreen shrub or small tree that is usually trimmed to below 2 m (6.6 ft) when cultivated for its leaves. It has a strong taproot. The flowers are yellow-white, 2.5–4 cm (0.98–1.57 in) in diameter, with seven or eight petals.

Flower of tea plant

The seeds of C. sinensis and C. oleifera can be pressed to yield tea oil, a sweetish seasoning and cooking oil that should not be confused with tea tree oil, an essential oil that is used for medical and cosmetic purposes, and originates from the leaves of a different plant.

C. sinensis plant, with cross-section of the flower (lower left) and seeds (lower right)

C. sinensis – MHNT

The leaves are 4–15 cm (1.6–5.9 in) long and 2–5 cm (0.79–1.97 in) broad. Fresh leaves contain about 4% caffeine, as well as related compounds including theobromine. The young, light-green leaves are preferably harvested for tea production; they have short, white hairs on the underside. Older leaves are deeper green. Different leaf ages produce differing tea qualities, since their chemical compositions are different. Usually, the tip (bud) and the first two to three leaves are harvested for processing. This hand picking is repeated every one to two weeks.

In 2017, Chinese scientists sequenced the genome of C. s. var. assamica . It contains about three billion base pairs, which was larger than most plants previously sequenced.

Descriptionedit

C. sinensis is native to East Asia, the Indian Subcontinent, and Southeast Asia, but it is today cultivated across the world in tropical and subtropical regions. It is an evergreen shrub or small tree that is usually trimmed to below 2 m (6.6 ft) when cultivated for its leaves. It has a strong taproot. The flowers are yellow-white, 2.5–4 cm (0.98–1.57 in) in diameter, with seven or eight petals.

Flower of tea plant

The seeds of C. sinensis and C. oleifera can be pressed to yield tea oil, a sweetish seasoning and cooking oil that should not be confused with tea tree oil, an essential oil that is used for medical and cosmetic purposes, and originates from the leaves of a different plant.

C. sinensis plant, with cross-section of the flower (lower left) and seeds (lower right)

C. sinensis – MHNT

The leaves are 4–15 cm (1.6–5.9 in) long and 2–5 cm (0.79–1.97 in) broad. Fresh leaves contain about 4% caffeine, as well as related compounds including theobromine. The young, light-green leaves are preferably harvested for tea production; they have short, white hairs on the underside. Older leaves are deeper green. Different leaf ages produce differing tea qualities, since their chemical compositions are different. Usually, the tip (bud) and the first two to three leaves are harvested for processing. This hand picking is repeated every one to two weeks.

In 2017, Chinese scientists sequenced the genome of C. s. var. assamica . It contains about three billion base pairs, which was larger than most plants previously sequenced.

Nomenclature and taxonomyedit

The generic name Camellia is taken from the Latinized name of Rev. Georg Kamel,SJ (1661–1706), a Moravian-born Jesuit lay brother, pharmacist, and missionary to the Philippines.

Carl Linnaeus chose his name in 1753 for the genus to honor Kamel’s contributions to botany (although Kamel did not discover or name this plant, or any Camellia, and Linnaeus did not consider this plant a Camellia but a Thea).

Robert Sweet shifted all formerly Thea species to the genus Camellia in 1818. The name sinensis means “from China” in Latin.

Four varieties of C. sinensis are recognized. Of these, C. sinensis var. sinensis and C. s. var. assamica (JW Masters) Kitamura are most commonly used for tea, and C. s. var. pubilimba Hung T. Chang and C. s. var. dehungensis (Hung T. Chang & BH Chen) TL Ming are sometimes used locally. The Cambod type tea (C. assamica subsp. lasiocaly) was originally considered a type of assam tea. However, later genetic work showed that it is a hybrid between Chinese small leaf tea and assam type tea.

Tea plants are native to East Asia, and probably originated in the borderlands of north Burma and southwestern China.

  • Chinese (small leaf) tea [C. sinensis var. sinensis]
  • Chinese Western Yunnan Assam (large leaf) tea [C. sinensis var. assamica

    Indian Assam (large leaf) tea

    ]

  • Chinese Southern Yunnan Assam (large leaf) tea [C. sinensis var. assamica]

Chinese (small leaf) type tea may have originated in southern China possibly with hybridization of unknown wild tea relatives. However, since no wild populations of this tea are known, the precise location of its origin is speculative.

Given their genetic differences forming distinct clades, Chinese Assam type tea (C. s. var. assamica) may have two different parentages – one being found in southern Yunnan (Xishuangbanna, Pu’er City) and the other in western Yunnan (Lincang, Baoshan). Many types of Southern Yunnan Assam tea have been hybridized with the closely related species Camellia taliensis. Unlike Southern Yunnan Assam tea, Western Yunnan Assam tea shares many genetic similarities with Indian Assam type tea (also C. s. var. assamica). Thus, Western Yunnan Assam tea and Indian Assam tea both may have originated from the same parent plant in the area where southwestern China, Indo-Burma, and Tibet meet. However, as the Indian Assam tea shares no haplotypes with Western Yunnan Assam tea, Indian Assam tea is likely to have originated from an independent domestication. Some Indian Assam tea appears to have hybridized with the species Camellia pubicosta.

Assuming a generation of 12 years, Chinese small leaf tea is estimated to have diverged from Assam tea around 22,000 years ago, while Chinese Assam tea and Indian Assam tea diverged 2,800 years ago. This divergence tea would correspond to the last glacial maximum.

Chinese small leaf type tea was introduced into India in 1836 by the British and some Indian Assam type tea (e.g. Darjeeling tea) appear to be genetic hybrids of Chinese small leaf type tea, native Indian Assam, and possibly also closely related wild tea species.

Cultivationedit

C. sinensis is mainly cultivated in tropical and subtropical climates, in areas with at least 127 cm (50 in) of rainfall a year. Tea plants prefer a rich and moist growing location in full to part sun, and can be grown in hardiness zones 7 – 9. However, the clonal one is commercially cultivated from the equator to as far north as Cornwall and Scotland on the UK mainland. Many high quality teas are grown at high elevations, up to 1,500 m (4,900 ft), as the plants grow more slowly and acquire more flavour.

Tea plants will grow into a tree if left undisturbed, but cultivated plants are pruned to waist height for ease of plucking. Two principal varieties are used, the small-leaved Chinese variety plant (C. s. sinensis) and the large-leaved Assamese plant (C. s. assamica), used mainly for black tea.

Chinese teasedit

The Chinese plant is a small-leafed bush with multiple stems that reaches a height of some 3 m. It is native to southeast China. The first tea plant variety to be discovered, recorded, and used to produce tea dates back 3,000 years ago, it yields some of the most popular teas.

C. s. var. waldenae was considered a different species, C. waldenae by SY Hu, but it was later identified as a variety of C. sinensis. This variety is commonly called Waldenae Camellia. It is seen on Sunset Peak and Tai Mo Shan in Hong Kong. It is also distributed in Guangxi province, China.

Indian and Nepali teasedit

Three main kinds of tea are produced in India:

  • Assam comes from the heavily forested northeastern section of the country, Assam. Tea from here is rich and full-bodied. In Assam, the first tea estate of India was established, in 1837.
  • Darjeeling is from the cool and wet Darjeeling region, tucked in the foothills of the Himalayas. Tea plantations reach 2,200 metres. The tea is delicately flavoured, and considered to be one of the finest teas in the world. The Darjeeling plantations have three distinct harvests, termed ‘flushes’, and the tea produced from each flush has a unique flavour. First (spring) flush teas are light and aromatic, while the second (summer) flush produces tea with a bit more bite. The third, or autumn flush gives a tea that is lesser in quality.

Nepali tea is also considered to be similar to the tea produced in Darjeeling, mostly because the eastern part of Nepal, where a large amount of tea is produced, has similar topography to that of Darjeeling.

Nilgiri is from a southern region of India almost as high as Darjeeling. Grown at elevations between 1,000 and 2,500 m, Nilgiri teas are subtle and rather gentle, and are frequently blended with other, more robust teas.

Seed-bearing fruit of C. sinensis

Pests and diseasesedit

Tea leaves are eaten by some herbivores, such as the caterpillars of the willow beauty (Peribatodes rhomboidaria), a geometer moth.

Biosynthesis of caffeineedit

Caffeine, a molecule produced in C. sinensis, functions as a secondary metabolite. Caffeine is a purine alkaloid and its biosynthesis occurs in young tea leaves and is regulated by several enzymes. The biosynthetic pathway in C. sinensis differs from other caffeine-producing plants such as coffee or guayusa. Analysis of the pathway was carried out by harvesting young leaves and using reverse transcription PCR to analyze the genes encoding the major enzymes involved in synthesizing caffeine. The gene TCS1 encodes caffeine synthase. Younger leaves feature high concentrations of TCS1 transcripts, allowing more caffeine to be synthesized during this time. Dephosphorylation of xanthosine-5′-monophosphate into xanthosine is the committed step for the xanthosines entering the beginning of the most common pathway. A sequence of reactions turns xanthosine into 7-methylxanthosine, then 7-methylxanthine, then theobromine, and finally into caffeine.

Biochemical pathway detailing caffeine synthesis in C. sinensis

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