Guwahati: Despite tea being one of the most popular non-alcoholic beverages, there is still not enough knowledge about Camellia sinensis - the plant from which tea comes. A recent study says the origins and distribution history of tea can only be fully understood through a multidisciplinary approach.

Not enough, if we are talking about Camellia sinensis, ​a ​ globally very important plant for humans on which the tea industry relies for making tea, one of the world’s most popular beverages is "data deficient". Tea is one world’s most popular non-alcoholic beverages, with more than 2 to 3 billion cups consumed daily, and is known for its health benefits.

Tea comes from the tea plant, Camellia sinensis (L.) Kuntze. Camellia sinensis is an evergreen, insect-pollinated species of the Theaceae family. Commercial tea is largely produced from two varieties of the tea plant: C. sinensis var. assamica, or the broad-leaf variety of the tea plant, and C. sinensis var. sinensis, or the small-leaf variety of the tea plant.

The C. sinensis var. ​a​ssamica, which is the broad-leaf variety, is prevalent across the native tea belt, while the C. sinensis var. sinensis, which is the small-leaf variety, prevails in eastern China, Taiwan, Japan, India’s Darjeeling, and tea-growing countries outside of Asia. However, both varieties can be found across wild and cultivated systems in these regions and hybridization occurs where the C. sinensis varieties overlap.

C. sinensis var. sinensis has a sweeter taste compared to C. sinensis var. assamica. It is generally chosen for cultivation in eastern China, Taiwan, and Japan to produce green and white teas, as well as in India’s Darjeeling region to produce delicate black teas. C. sinensis var. ​a​ssamica is generally used in western China, Myanmar, and Assam to produce black, green, and pu-erh teas.

Different types of tea like black tea, green tea, white tea, and others all come from Camellia sinensis and the difference is in the process the leaves go through after being plucked.

The State of the World’s Trees report (2021) brought out by Botanic Gardens Conservation International says that tea is today cultivated in more than 40 countries worldwide, and though the origin of the species is thought to be in China and Southeast Asia, its wild distribution is still unknown.

Many of the very old records of the species can be traced back to the cultivation of ancient (sometimes abandoned) tea plantations. Due to its long history in cultivation, distinguishing between the wild population and naturalized plants from cultivated sources is very difficult, it may be that no wild tea plants exist today. Until more information is known, Camellia sinensis has been assessed with the conservation status "Data Deficient," it says.

The report, compiling work led by the Global Tree Assessment (GTA), is the culmination of five years of research to identify major gaps in tree conservation efforts. It is one of the first assessments of the world’s threatened trees.

The category of Data Deficient (DD) indicates that there is inadequate information to determine the degree of threat faced by a taxon. DD has generally been applied where there is insufficient distribution data or where the data is too uncertain to assign a category.

ADOPT SEED OF TEA PLANT:

In fact, Kew’s Millennium Seed Bank(MSB), based at Wakehurst in the UK (Kew’s Wild Botanic Garden in Sussex) had launched an initiative asking people to adopt a seed of the tea plant which will be very important for its conservation. It holds over 36,000 wild plant species and is an invaluable resource for plant science and conservation. By storing the world's seeds, the MSB aims to provide an insurance policy against the extinction of plants in the wild. Donations made through the programme will help with seed sourcing, collecting, storage, and research which is undertaken by the Millennium Seed Bank Partnership.

​ORIGIN OF TEA DRINKING​

Tea researcher Dr. Pradip Baruah of the Tocklai Tea Research Institute says tea drinking originated in China about 5,000 years ago and was cultivated in South-East China at first. The word ‘tea’ is derived from the word ‘t’e’ of the Chinese Fukian dialect. In Cantonese, tea is known as ‘Cha’. In fact, there are names for tea in 98 languages, from Afrikaans to Uzbek.

There are many legends as to how tea drinking started. One legend says Shen Nung, 2737 B.C. While he was on a hunting trip in wild forests, some tea leaves carried by the wind fell into his boiling water pot, and he discovered the properties of the leaves on drinking unknowingly.

The first book exclusively on tea was published in 780 A.D. by Lu Yu (733-804), respected as the Sage of Tea. The book ‘Ch’a Ching’ or ‘The Classic of Tea’ in three volumes is divided into ten chapters, each describing various kinds of tea, cultivation, manufacturing methods, etc., and giving information on the tea-growing districts of China. The use of tea as a beverage commenced towards the end of the sixth century in China.

An article on “From the Wild to the Cup: Tracking Footprints of the Tea Species in Time and Space" says the earliest literary sources on the origin of tea focus more on the drink and much less on the plant, but generally point to China as the most probable origin. It is thought that tea drinking in China began earlier than 2000 B.C., but its use as a popular commercial beverage would only gain momentum toward the end of the sixth century.

“Owing to its popularity, long history of usage and diverse roles (cultural, religious, economic, and therapeutic), the origins and distribution history of tea can only be fully understood through a multidisciplinary approach." Such an approach may incorporate disciplines such as plant biochemistry, genetics/genomics, paleontology, history, linguistics, as well as social anthropology. For instance, linguistics could be useful in understanding the expansion history of the tea crop and the tea-drinking culture​. ​The study notes that there are only two main phonetic forms of the names that refer to tea across the world (“Cha” -derived and “Te”-derived forms with only a few exceptions,​" the study notes. ​

The study says future research on tea should explore the potential effect of​ climate change (particularly temperature and rainfall patterns) on the tea's biochemical profile, as tea plants are thought to be​ highly sensitive to environmental variations.