Editing Canna (plant) (section)

===Agricultural varieties===
[[Image:Canna Edulis 2003072001 0014.jpg|thumb|left|''Canna'' (Agriculture Group) 'Edulis Dark']]
The [[Canna Agriculture Group]] contains all of the varieties of ''Canna'' grown in agriculture. "Canna achira" is a generic term used in South America to describe the cannas that have been selectively bred for agricultural purposes, normally derived from ''[[Canna discolor|C. discolor]]''. It is grown especially for its edible [[rootstock]] from which starch is obtained, but the leaves and young seeds are also edible, and achira was once a staple food crop in [[Peru]] and [[Ecuador]].<ref name=Khoshoo/> Trials in Ecuador using a wide range of varieties have shown that achira can yield on average 56 tons of rhizomes and 7.8 tons of extractable starch per hectare. However, the crop needs 9–12 months to mature to full productivity.<ref>{{cite book|last=Hermann|first=Michael|title=Crop growth and starch productivity of edible canna|year=1995–1996|publisher=International Potato Center|pages=295–301|url=https://books.google.com/books?id=6mE35sBhT48C}}</ref>

Many more traditional kinds exist worldwide; they have all involved human selection, so are classified as agricultural cultivars. Traditionally, ''Canna edulis'' Ker Gawl. has been reputed to be the species grown for food in South America, but ''C. edulis'' probably is simply a synonym of ''C. discolor'', which is also grown for agricultural purposes throughout Asia.<ref>{{cite journal |jstor=4256780 |title=The utilization of edible ''Canna'' plants in southeastern Asia and southern China |author=Nobuyuki Tanaka |journal=Economic Botany |volume=58 |issue=1 |pages=112–114 |year=2004 |doi=10.1663/0013-0001(2004)058[0112:noep]2.0.co;2 |s2cid=198152695 }}</ref><ref>{{Cite web |url=http://www.jjbot.com/English/Vol.73E/73-3E.html |title=On the Genus Canna in Yaeyama Islands, the Ryukyus, Japan |access-date=2007-07-02 |archive-url=https://web.archive.org/web/20070928082450/http://www.jjbot.com/English/Vol.73E/73-3E.html |archive-date=2007-09-28 |url-status=dead }}</ref><ref>{{Cite web |url=http://www.ffcr.or.jp/zaidan/FFCRHOME.nsf/7bd44c20b0dc562649256502001b65e9/cb71f616e311cc9549257177000afed8/$FILE/211(4)4.pdf |title=Edible Canna and its Starch: An Under-Exploited Starch-Producing Plant Resource |access-date=2007-07-02 |archive-url=https://web.archive.org/web/20080227150439/http://www.ffcr.or.jp/zaidan/FFCRHOME.nsf/7bd44c20b0dc562649256502001b65e9/cb71f616e311cc9549257177000afed8/$FILE/211(4)4.pdf |archive-date=2008-02-27 |url-status=dead }}</ref><ref>{{Cite web |url=http://www.econbot.org/_publications_/index.php?sm=03 |title=Progress in the Development of Economic Botany and Knowledge of Food Plants. |access-date=2007-07-02 |archive-url=https://web.archive.org/web/20070708224604/http://www.econbot.org/_publications_/index.php?sm=03 |archive-date=2007-07-08 |url-status=dead }}</ref><ref>{{cite journal|last=Hermann|first=Michael|author2=NK Quynh|author3=D. Peters|title=Reappraisal of Edible Canna as a High-Value Starch Crop in Vietnam|journal=CIP Program Report 1997-98|year=1999|url=http://www.cipotato.org/publications/program_reports/97_98/50canna.pdf|access-date=27 November 2011|archive-url=https://web.archive.org/web/20110927143833/http://www.cipotato.org/publications/program_reports/97_98/50canna.pdf|archive-date=2011-09-27|url-status=dead}}</ref>