|Indian shot Quick Facts
|Canna indica L
|South eastern United States, Mexico, Central America, the West Indies and much of South America
|Initially green or purplish in color and turn brown as they mature
|Capsules, ellipsoid to sub globose or obovoid, soft, echinate (spiny), and 2-2.5 centimeters long
|Beneficial for headaches, diarrhea, yaws, acute hepatitis, traumatic injuries, nose bleeding, tonsillitis, itches, persistent sores, earaches, eye diseases and many more
The genus name canna comes from the Greek kanna and the Celtic cana which refers to ‘a reed-like plant’ and is also the root of the musical term ‘canon’. The name canna was applied to this genus as early as 1576 and was formally given to the genus by Linnaeus in his seminal work Species Plantarum. Species epithet ‘edulis’ means ‘edible’, referring to the starchy rhizomes. Canna is famously called Indian Shot. The story is that during an uprising in India, those loyal to the British were running out of ammunition. So they filled the barrels of their rifles with canna seed. The rock hard, perfectly round seed was used as a substitute for lead shot in muzzle loading guns. Hence the name Indian Shot.
Each and every part of the plant is useful for having medicinal activity. The plant provides food (mainly the root), medicines and a range of commodities. It is often cultivated on a home scale for these uses, mostly in S. America and Southeast Asia; whilst it is grown on a small scale in Australia as a commercial source of arrowroot. The plant is widely grown through the tropics and subtropics as an ornamental, being valued especially for its flowers and attractive leaves.
Indian shot is a coarse, rhizomatous, erect, robust, long lived perennial, herb that grows from 90 centimeters to 3 meters tall. The plant is found growing around villages, roadsides, in coconut plantations, clearings, in forest near streams, marshes, lake margins, spoil banks, roadside ditches, wetland edges, stream banks, old gardens, disturbed sites, waste areas and other moist areas. The plant is grown on most types of soil, except heavy clay, provided there is adequate drainage, since it will not tolerate water logging. The best yields are obtained on deep sandy loam, rich in humus. Roots are thick, cylindrical and creamy white in color with a diameter of 2-5 mm with numerous root hairs. Thinner primary and secondary lateral roots are also seen.
Rhizomes are yellowish white or pinkish on the outside and yellowish white within. At maturity, they turn brownish externally due to a thick outer covering. Rhizomes may be monopodial or sympodial, stoloniferous or tuberous. Rhizomes are sympodial with Y-shaped axes.
Stem is a pseudo stem which reaches up to 1.5-2m in height. It is erect, herbaceous, sturdy and cylindrical encircled by the sheathing leaf bases.
Leaves are large and foliaceous, lanceolate or ovate reaching up to 65-70 cm in length and 30-35 cm in width. Having large laminae up to 60 cm long. Inflorescence is waxy-glucose erect peduncle about 30 cm long. Leaves are dark green with purplish brown margins and veins. They are carline, simple, alternate and spiral. The oblong leaves have their petioles extending downwards to form a sheathing base around the stem. The lamina is pinnately, parallel veined. Leaf margins appear smooth and wavy with acute apex. Surface of the upper leaves are green, dark copper or purplish, while the lower surface covered with a layer of white as talcum powder.
The flowers can be red, yellow or occasionally red and yellow (i.e. yellow with red spots or vice versa) and are quite showy. They are borne singly or in pairs (i.e. monochasial cymes) and arranged into larger branched clusters (i.e. with 6-20 flowers) at the tips of the flowering stems. Each flower appears to have five ‘petals’ but these are actually other floral structures (i.e. staminodes and petaloid filaments) that have become modified to imitate petals. The petals are actually the three bract-like structures below these false ‘petals’ (4-6.5 cm long and 0.4-0.7 cm wide). They are fused together at the base (i.e. into a perianth tube 5-15 mm long) and their margins are curved inwards. Each flower has three slightly different types of false ‘petals’ (i.e. three outer staminodes, an inner staminodes and a petaloid filament). The three outer staminodes are relatively broad (3.5-6 cm long and 0.5-1.5 cm wide) while the inner staminode (i.e. labellum) is usually somewhat narrower (up to 4-5 cm long and 0.8 cm wide) with its tip bent backwards (i.e. it has a recurved apex). The single petaloid filament is narrower again (3-4 mm wide) and has an anther about 10 mm long about half way up one of its sides. Each flower also has three narrow sepals (9-17 mm long and 2-5 mm wide) and their bases are also surrounded by a floral bract (5-30 mm long and 5-15 mm wide) and bracteoles (5-20 mm long and 3-8 mm wide). Flowering occurs mainly during August to October. Flowers are hermaphrodite.
The papery capsules are oval (i.e. ellipsoid) to almost rounded (i.e. sub-globose) in shape, about 1.5-3 cm long and 1.5-2 cm wide and are crowned by the persistent sepals. They are initially green or purplish in color and covered in numerous short projections (i.e. they are verrucose), but turn brown as they mature and may lose some or all of their tiny projections. They split open at maturity to release numerous smooth, black, rounded (i.e. spherical) or egg-shaped (i.e. ovoid) seeds. These seeds are relatively large about 5-8 mm long and 4-7 mm wide and are very hard. Normally seeds are initially white and when mature, black with chestnut brown spots are protected with a smooth coat. Fruiting occurs mainly during October.
Canna edulis (Indian shot) appears to have originated in the Andean region of South America. There is evidence of its cultivation on the Peruvian coast about 2500 BC (earlier than maize and cassava). In South America it now extends from the north, throughout the Amazon basin and as far south as northern Chile; in Central America and the West Indies it has become naturalized as a weed (occasionally cultivated), and it has been spread to parts of Australia, Polynesia and Africa.
- Plant is used in the treatment of women’s complaints.
- Decoction of the root with fermented rice is used in the treatment of gonorrhea and amenorrhea.
- Plant is also considered to be demulcent, diaphoretic and diuretic.
- There are numerous medicinal uses of rhizome extracts reported from South-East Asia, against headaches, diarrhea, yaws, acute hepatitis, traumatic injuries, as a diuretic, and against nose bleeding.
- Root is diaphoretic and diuretic and is used in the treatment of fevers.
- An infusion of the rhizome is said to be febrifuge and stimulant, whilst a decoction is said to be diaphoretic and diuretic.
- Rhizome is also made into an emollient cataplasm.
- Leaves and the powdered seeds are mixed and used to treat dermatoses.
- Seeds are demulcent and are mixed with water in a poultice which is placed on the forehead to remedy headaches.
- They are ground into a powder and used as an anti-infective agent or as a treatment for itches, persistent sores and ‘bush yaws.
- Seed juice is used to relieve ear aches.
- Flowers are said to cure eye diseases.
- Paste of plant is used for tonsillitis in Bangladesh.
- Rhizome has been used with other herbs for cancer treatment in Thailand.
- Leaves are used for malaria in southwest Nigeria.
- It is also used in the treatment of acute jaundice type of hepatitis.
- Decoction of rhizome used as diuretic in Philippines.
- When macerated in water, it is used to alleviate nosebleeds.
- Infusion of leaves used as diuretic; rhizomes are used as emollient in Costa Rica.
- Decoction of rhizomes is used in fevers, dropsy and dyspepsia.
- Flowers may be used for external wound bleeding use 10 to 15 g dried material in decoction.
- In folkloric medicine, root decoction is used for the treatment of fever, dropsy and dyspepsia.
- Rhizome is used in ringworm in Khagrachari.
- Decoction of the rhizome is used to treat gonorrhea (anti-blennorrhagia) and cold of the bladder.
- Decoction of the stems is used as a drink or bath to regain energy.
- Freshly squashed leaves are used in baths against rheumatic pains and arthritis and are applied to ulcers.
- Juice of leaves is used against mercurial’s as a diuretic, and in compresses.
- Juice of unripe fruit is used against inflammation of the ear.
- Fruit can be used to treat constipation of children.
- Mush made from the rhizome is taken as a remedy for yaws in Cambodia.
- Decoction of fresh rhizomes is prescribed in acute hepatitis in Hong Kong.
- Crushed fresh rhizomes are applied topically for traumatic injuries in traditional medicine in Indo-China.
- Macerated rhizomes in water are applied to alleviate nose bleeding.
- Root is a source of canna starch and is used as arrowroot.
- Very young tubers are eaten cooked, they are sweet but fibrous.
- Flour can be made from the rhizomes by peeling, drying and milling.
- Young shoots can be eaten as a green vegetable, and leaves are suitable for wrapping and as plates.
- In Peru they are baked for up to 12 hours, after which time they become a white, translucent, fibrous and somewhat mucilaginous mass with a sweetish taste.
- Immature seeds are cooked in tortillas.
- Seeds also have been used as an ingredient or a substitute for coffee.
- Powdered tubers were used to thicken sauces and improve the texture of some prepared foods.
- Canna starch is used to make cellophane noodles known as miến dong in Vietnam.
- Plant yields a fiber from the stem it is a jute substitute.
- Fiber obtained from the leaves is used for making paper.
- Leaves are harvested in late summer after the plant has flowered; they are scraped to remove the outer skin and are then soaked in water for 2 hours prior to cooking.
- Fibers are cooked for 24 hours with lye and then beaten in a blender. They make a light tan brown paper.
- Purple dye is obtained from the seed, It is not very permanent.
- Smoke from the burning leaves is said to be insecticidal.
- Both leaves and the rhizomes can be used as cattle feed.
- It is also well known as a garden ornamental because of its beautiful flowers and foliage of various colors.
- Black and hard-coated seeds are used as beads or made into rosaries.
- They are also used in percussion instruments and rattles, especially in Africa.
- Fumigated stems and leaves are used as an insecticide, and all plant parts but especially the rhizomes make effective molluscicides.
- It is also one of several plant species that is used for waste water treatment.
- Large leaves are sometimes used as plates.
- Seeds are also used in hula rattles.
- They are also used as beads to make rosaries and necklaces.
- It can be used for the treatment of industrial waste waters through constructed wetlands.
- It is effective for the removal of high organic load, color and chlorinated organic compounds from paper mill wastewater.
- Archaeological evidence suggests that Canna indica L. was one of the first plants to be cultivated during incipient civilization of Peru and Argentina.
- Seed is used in jewelry making, and it used to be used instead of rifle bullets.
- Plant has a large biomass production and in some countries is used for thermal energy production i.e. as biofuel.
- It can produce high biomass in different soils and mainly in the aquatic environment.
- It can successfully remove heavy metals and other pollutants from soil and water.
- Root bark and stalks are used to the cattle suffering from poisoning.
- Leaves are used for wrapping up parcels in Asia as well as in Panama.
- It is also used to wrap around tamales (pastries made of corn filled with beans, meat, and pepper), they are fed to animals, and have sometimes been eaten as legume by the poor (Brazil).
- Seeds are used as beads to make necklaces and bracelets after boiling as toys, as ammunition for children’s shotguns or as a substitute for lead in hunting.
- Cannas are a traditional gift for Father’s Day in Thailand.
Prevention and Control
Moves are being made to alert the horticultural industry, particularly suppliers of ornamental plants via nurseries and seed catalogues, of the environmental risks posed by invasive plants. C. indica is one of the species now being brought to their attention as an invasive species in Australia and the USA.
C. indica is very difficult to control using physical or mechanical means, due to the presence of rhizomes, even a small fragment of which, if left in the soil, will regrow.
No attempts have been made at identifying potential bio-control agents, and most pests that attack C. indica are generalists, however, new, species-specific fungi Cercospora cannae and Puccinia cannacearum have been proposed from India, and which may merit further investigation.
No information is available on the use and efficacy of herbicides on C. indica.
Control by utilization
Noting the local and commercial use of the rhizome as a food source, it would appear that C. indica is a suitable candidate for control by utilization, whereby at least the cost of control could be repaid by sales of the harvested plant parts.