Editing Camellia sinensis (section)

== Description ==
''Camellia sinensis'' is native to [[East Asia]], the [[Indian Subcontinent]], and [[Southeast Asia]], but it is today cultivated all around the world in tropical and subtropical regions. It is an evergreen [[shrub]] or small [[tree]] that is usually trimmed to below {{convert|2|m|ft|abbr=on}} when cultivated for its leaves. It has a strong [[taproot]]. The flowers are yellow-white, {{convert|2.5|–|4|cm|in|abbr=on}} in diameter, with seven or eight petals.
[[File:Flower of Tea plant.jpg|thumb|Flower of tea plant]]

[[File:Pollen grains of a Tea plant.jpg|thumb|Pollen grains of ''C. sinensis'']]

The seeds of ''C. sinensis'' and ''[[Camellia oleifera|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.

[[File:Camellia sinensis - Köhler–s Medizinal-Pflanzen-025.jpg|right|thumb|''C. sinensis'' plant, with cross-section of the flower (lower left) and seeds (lower right)]]
[[File:Camellia sinensis MHNT.BOT.2016.12.24.jpg|thumb|''C. sinensis'']]

The leaves are {{convert|4|–|15|cm|in|abbr=on}} long and {{convert|2|–|5|cm|in|abbr=on}} broad. Fresh leaves contain about 4% [[caffeine]], as well as related compounds including [[theobromine]].<ref>{{cite web |publisher=Purdue |url=http://www.hort.purdue.edu/newcrop/duke_energy/Camellia_sinensis.html |title=Camellia sinensis |access-date=18 February 2008 |archive-date=24 September 2010 |archive-url=https://web.archive.org/web/20100924055240/http://www.hort.purdue.edu/newcrop/duke_energy/Camellia_sinensis.html |url-status=live}}</ref> The young, light-green leaves are preferably harvested for tea production when 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.''<ref>{{cite journal |vauthors=Xia EH, Zhang HB, Sheng J, Li K, Zhang QJ, Kim C, Zhang Y, Liu Y, Zhu T, Li W, Huang H, Tong Y, Nan H, Shi C, Shi C, Jiang JJ, Mao SY, Jiao JY, Zhang D, Zhao Y, Zhao YJ, Zhang LP, Liu YL, Liu BY, Yu Y, Shao SF, Ni DJ, Eichler EE, Gao LZ |display-authors=6 |title=The Tea Tree Genome Provides Insights into Tea Flavor and Independent Evolution of Caffeine Biosynthesis |journal=Molecular Plant |volume=10 |issue=6 |pages=866–877 |date=June 2017 |pmid=28473262 |doi=10.1016/j.molp.2017.04.002 |doi-access=free|bibcode=2017MPlan..10..866X }}</ref> It contains about three billion base pairs, which was larger than most plants previously sequenced.<ref>{{Cite news |url=https://www.bbc.co.uk/news/science-environment-39747720 |title=Secrets of tea plant revealed by science |last=Briggs |first=Helen |date=2 May 2017 |work=BBC News |access-date=2 May 2017 |language=en-GB |archive-date=6 August 2018 |archive-url=https://web.archive.org/web/20180806051540/https://www.bbc.co.uk/news/science-environment-39747720 |url-status=live}}</ref>