Indigofera circinnata
Introduction
A spiny, rigid shrub with white and pink flowers and distinctive circular pods, that is used in traditional medicine in South Africa. The genus Indigofera is well known for producing indigo dye and many species in the genus are used worldwide in traditional medicine against various ailments.
Description
Description
Indigofera circinnata is a perennial subshrub that usually grows less than 2 m tall, with hairy branches, trifoliolate leaves with leaflets 6-8 mm long, and orange spines that can grow up to 25 mm long. Flowers are small, bicolored white and fleshy pink, with gaping lips. It is a pod-bearing plant with unusual pale brown, coiled pods producing 3 or 4 seeds.
Conservation Status
Status
Indigofera circinnata is not endangered; it is assessed as Least Concern (LC) on the Red list of South African plants.
Distribution and habitat
Distribution description
This species is found primarily in the seasonally dry tropical biome in South Africa, Botswana and Zimbabwe. In South Africa, it is distributed in Gauteng, Mpumalanga and Limpopo provinces, where it grows in the drier parts of the country; the plant is drought tolerant.
Indigofera circinnata exhibits a versatile habitat range, with the ability to thrive in diverse environments. The species is commonly found in grassland, savanna, open woodland, and disturbed areas, such as roadsides and fallow lands. It is well adapted to a variety of soil types, including sandy, loamy and clayey soils, and can tolerate a wide range of pH levels. Indigofera circinnata is often found growing in areas with annual precipitation ranging from 300 to 1 500 mm, although it has been reported to tolerate both higher and lower precipitation levels.
Derivation of name and historical aspects
History
Indigofera circinnata is a member of the Fabaceae, one of the largest plant families. The genus Indigofera, to which I. circinnata belongs, is the third largest within the Fabaceae, encompassing approximately 750 species worldwide. The name Indigofera meaning ‘indigo bearing’ is derived from the historical use of certain species as a source of indigo, a purple dye. The specific epithet circinnata is derived from Latin, circinata meaning ‘rounded’, referring to the unique characteristic of the pods of I. circinnata, which coil upon themselves in a distinctive manner.
There are preserved specimens of this species in the Rio de Janeiro Botanical Garden Herbarium Collection, Brazil and in other botanical institues in France, Belgium, Sweden, Switzerland, the United Kingdom, the United States of America and the Netherlands.
Ecology
Ecology
Herbivores have been observed consuming the mature seed pods of species of Indigofera, which facilitates the dispersal of seeds (personal observation). As the seed pods ripen, they crack open, releasing the seeds which fall on the ground. Under favourable conditions, these seeds readily germinate. Notably, the occurrence of fire can accelerate the germination process in these plants. Moreover, secondary metabolites produced by species of Indigofera serve as a defense mechanism against herbivores and pathogens, functioning as chemical defenses to protect the plant from potential harm (Schrire et al. 2009).
Uses
Use
In general, the roots and leaves of many plant species are commonly employed for their medicinal properties, which include remedies for ailments such as sore throat, fungal infections, colds, and respiratory infections. The utilization of these plant parts for medicinal purposes varies across different countries and regions. Within the genus Indigofera, there are economically significant species known for their production of indigo dye. Additionally, some species within this genus have important applications as pasture legumes, as well as for crop shading, soil protection, green humus covering, erosion control, and ornamental plants (Schrire 2013; Semenya & Maroyi 2019). Indigofera circinnata is one of the plants used by traditional healers in South Africa to treat fungal infections and related ailments, and plant extracts showed antifungal activity against the tested microorganisms (Machaba & Mahlo 2017).
Growing Indigofera circinnata
Grow
The seeds of Indigofera circinnata are effectively disseminated in their natural environment. This plant species can be readily cultivated by utilizing the pods for germination, which occurs with ease under favourable conditions. Notably, Indigofera circinnata demonstrates improved growth and drought tolerance when cultivated outdoors. While greenhouse cultivation of this species has not been attempted, it is proposed that a similar approach employed for other species within the same genus could potentially yield successful results.
Although not generally cultivated as a garden ornamental, Indigofera circinnata shows promise as a low-maintenance, drought-tolerant plant well suited to bushveld gardens.
References
- Bester, S.P. 2020. Observation of Indigofera circinnata, Waterberg, Limpopo. iNaturalist. Online. https://www.inaturalist.org/observations/65887043.
- Harvey, W.H. 1861. Leguminosae. In: W.H. Harvey and O.W. Sonder (eds). Flora Capensis 2 (Leguminosae to Loranthaceae):1-285. Hodges, Smith and Co., Dublin.
- Machaba, T.C. & Mahlo, S.M. 2017. Antifungal activity of medicinal plants used traditionally for the treatment of fungal infections and related ailments in South Africa. International Journal of Pharmacological and Pharmaceutical Sciences 11(6): 395-400.
- Plants of the World Online. Indigofera circinnata Benth. ex Harv. https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:499146-1. Accessed 16 March 2023.
- RB - Rio de Janeiro Botanical Garden Herbarium Collection, Occurrences search Indigofera circinnata. https://www.gbif.org/occurrence/search?basis_of_record=PRESERVED_SPECIMEN&taxon_key=2972220. Accessed 17/05/23.
- SAplants. 2009. Image of Indigofera circinnata, in savanna between Waterpoort & Mopane, Limpopo. Wikimedia Commons. https://commons.wikimedia.org/wiki/File:Indigofera_circinnata_1DS-II_3-2208.jpg.
- Schrire, B.D. 2012. Papilionoideae-Indigofereae. Flora Zambesiaca 3(4): 30-31.
- Schrire, B.D. 2013. A review of tribe Indigofereae (Leguminosae–Papilionoideae) in southern Africa (including South Africa, Lesotho, Swaziland & Namibia; excluding Botswana). South African Journal of Botany 89: 281–283.
- Schrire, B.D., Lavin, M., Barker, N.P. & Forest, F. 2009. Phylogeny of the tribe Indigofereae: geographically structured more in succulent-rich and temperate settings than in grass-rich environments. American Journal of Botany 96(4): 816–852.
- Semenya, S.S. & Maroyi, A. 2019. Source of plants used by traditional healers for respiratory infections and related symptoms in the Limpopo Province. Journal of Biological Sciences 19: 101-121.
- Van der Merwe, T. 2019. Observation of Indigofera circinnata, Makhado, Limpopo. iNaturalist. Online. https://www.inaturalist.org/observations/20967490.
- Van der Merwe, T. 2019. Observation of Indigofera circinnata, Nzhelele Nature Reserve. iNaturalist. Online. https://www.inaturalist.org/photos/102529295.
- Von Staden, L. 2020. Indigofera circinnata Benth.ex. Harv. National Assessment: Red List of South African Plants version 2020.1. Accessed on 16 March 2023.
- Whitaker’s Words Online. Search circinata. https://latin-words.com/. Accessed 4 May 2023.
Credits
Tambudzani Caroline Machaba & Dr Moleseng Claude Moshobane
Thohoyandou National Botanical Garden
May 2023
Acknowledgements: Images by Troos van der Merwe, S.P. Bester and SAplants.
Plant Attributes:
Plant Type: Shrub
SA Distribution: Gauteng, Limpopo, Mpumalanga
Soil type: Sandy, Clay, Loam
Flowering season: Early Summer
PH: Acid, Neutral
Flower colour: White, Pink
Aspect: Full Sun
Gardening skill: Easy
Special Features:
Drought resistant
Medical plant
Horticultural zones
Rate this article
Article well written and informative
Rate this plant
Is this an interesting plant?
Login to add your Comment
Back to topNot registered yet? Click here to register.