Suppression

Ground pineapple

Category: Medicines - plant based

Type

Voluntary

Introduction and description

 

Thonningia is a monotypic genus of flowering plants in the family Balanophoraceae containing the single species Thonningia sanguinea.

Common names for the plant include ground pineapple. A familiar plant to humans, it has an extremely long list of common names in many African languages. Many names are inspired by the resemblance of the plant's inflorescence to a pineapple or palm tree. Some of the names can be translated as pineapple of the bush (from Anyi), duiker's kolanut (from Igala), and crown of the ground (from Yoruba).

Description

 

This species is a fleshy dioecious herb growing from an underground tuber. It is parasitic on other plants via its tuber. The branching, yellowish tuber extends horizontally up to 10 or 15 centimeters through the soil. It forms bulb-like swellings at the points where it attaches to the roots of its host plants. These swellings, or galls, can reach over 18 centimeters wide.  The tuber can resemble a rhizome, but there is no true rhizome.

The stem is coated with spirals of scale-like leaves. The leaves are not green; there is no chlorophyll, as the plant obtains nutrients from hosts and does not need to photosynthesize. The flowering stem emerges from the ground to produce a bright red or pink inflorescence containing male and female flowers. The crowded flower heads are covered in scales. The inflorescence is up to 15 to 20 centimeters long.

Habitat, distribution, and ecology

Thonningia sanguinea is distributed throughout much of southern and western Africa, particularly the tropical regions.

This plant grows in forests and other habitat. It can often be found in plantations, where it parasitizes such crop trees as Hevea brasiliensis (rubber), Phoenix dactylifera (date), and Theobroma cacao (cocoa).

The species is pollinated by flies and ants. Flies of the families Muscidae and Calliphoridae and ants of genus Technomyrmex visit the flowers to obtain nectar, pollinating the flowers as they enter. Muscid flies of genus Morellia lay eggs in the flowers and the larvae feed on the male flowers when they emerge. This could be an example of mutualism; as the fly pollinates the plant, it provides a site for egg-laying and nutrition for the larvae.

Medicinal Uses

 

The plant is used as a traditional remedy in many African cultures.  It has been used to treat sexually transmitted diseases in Ghana and diarrhoea in the Congo. A portion of the leaves is used in those with worms. Mixed with Capsicum, it is used topically on haemorrhoids and torticollis. It is used for leprosy, skin infections and abscesses, dental caries, gingivitis, and heart disease. In Zaire, it is said to prevent incontinence and bedwetting.

There is no analysis from Dr Duke, but the list of activity would indicate that it is an anti-fungal, anti-viral and anti-bacterial.

The other uses for the plant include as an ingredient in the poison applied to hunting arrows by peoples of Côte d'Ivoire.  It is even used as a flavouring for soup. In some areas, the flower heads are considered to be an aphrodisiac.

In Ghana and Côte d'Ivoire, the spiky flower heads are tied to the ankles of toddlers to encourage them to learn to walk; the spikes keep them from sitting down. All parts of the plant are used.

The plant is considered a weed in some places, such as rubber plantations, where it can become abundant.  Sometimes weeds are potentially more important than the crop!

Related observations