Indigofera trita
(Asian indigo)

Pictures

Picture	Title	Caption	Copyright
Title Flowers and leaves Caption Indigofera trita (Asian indigo): flowers and leaves. Copyright ©Mark Marathon/via wikipedia - CC BY-SA 4.0	Flowers and leaves	Indigofera trita (Asian indigo): flowers and leaves.	©Mark Marathon/via wikipedia - CC BY-SA 4.0

Identity

Preferred Scientific Name

• Indigofera trita L.f.

Preferred Common Name

• Asian indigo

Variety

• Indigofera trita var. maffei
• Indigofera trita var. marginulata
• Indigofera trita var. subulata

Other Scientific Names

• Galega frutescens Mill.
• Indigofera arcuata Willd.
• Indigofera canescens Lam.
• Indigofera carinata De Wild.
• Indigofera cinerea Willd.
• Indigofera coccinea Lour.
• Indigofera hedysarioides Lam.
• Indigofera heterophylla C.Presl
• Indigofera laevis Rydb.
• Indigofera leschenaultii DC.
• Indigofera macilenta Standl.
• Indigofera oxycarpa Desv.
• Indigofera quartiniana A.Rich.
• Indigofera rigida Willd.
• Indigofera rosei Rydb.
• Indigofera subulata Griseb.
• Indigofera tephrosioides Micheli
• Indigofera timorensis DC.
• Indigofera trifoliata var. timorensis (DC.) Miq.
• Indigofera trita var. trita
• Tephrosia frutescens (Mill.) DC.

International Common Names

• Spanish: añil; azulita; frijolillo; frijolillo de llano

Local Common Names

• India: three-leaved indigo
• Madagascar: laindramotilahy; laindramotio; raindramotio
• Mexico: mozotillo
• Sri Lanka: wal-awari

Subspecies

• Indigofera trita subsp. scabra

Summary of Invasiveness

Many species in the genus Indigofera have been introduced throughout the tropics to be used as ornamentals, forage, ground covers, and medicinal herbs (PROTA, 2014). I. trita behaves as a weed on disturbed ground and is often invasive even in areas within its native distribution range (Chadburn, 2012). The species is included in the Global Compendium of Weeds (Randall, 2012) and it is also listed as invasive in India and as a weedy species in areas of Africa and Australia (Wilson and Rowe, 2008; Reddy, 2008; Chandra, 2012). The infraspecific taxa I. trita subsp scabra is considered invasive in the Dominican Republic (Kairo et al., 2003). 

Taxonomic Tree

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Fabales
•                         Family: Fabaceae
•                             Subfamily: Faboideae
•                                 Genus: Indigofera
•                                     Species: Indigofera trita

Notes on Taxonomy and Nomenclature

Fabaceae is one of the largest families of flowering plants. This family includes about 745 genera and 19500 species which can be found throughout the world growing in a great variety of climates and environments (Stevens, 2012). The genus Indigofera includes over 750 species of shrubs, shrublets, perennial herbs, or rarely annual herbs or small trees (Flora of China Editorial Committee, 2014). Several species within this genus are used to produce the dye indigo and other species, including the species I. trita, are used in traditional medicine to alleviate pain (Kumar et al., 2013). Several subspecies and varieties of I. trita are recognized (Chadburn, 2012). Chauhan and Pandey (2015) describe the varieties present in India.

Description

Perennial, erect or subscandent woody herb or shrub, 0.5-2 m tall. Taproot present. Nodules present. Stems and branches arching, spreading or decumbent. Branches becoming whitish. Leaves are trifoliolate, about 0.8-2.5 cm long. Leaflets are about 1.2-2.6 cm long, obovate or oblong, velvety on both sides. Inflorescence is 6-12-flowered, 4.5 cm long or less. Flowers are zygomorphic. Calyx 5-lobed, glabrous, petals separate, clawed, pinkish to rose, corolla papilionaceous. Wing petals narrow, oblanceolate to oblong. Keel petals auriculate, spurred, or gibbous, abruptly curved, or spirally coiled. Fruit a hairy legume, dehiscent, oblong or ellipsoidal, coriaceous or becoming woody, 3-10 seeded. Seeds ovoid to rounded in outline, surface smooth, olive, brown, or black in colour (USDA-NRCS, 2014). 

Plant Type

Distribution

I. trita has an extremely large geographic range. Consequently, its native distribution range is still uncertain. It can be found throughout Africa, Asia and in some parts of Australia, and in these three geographical regions it is considered native (Chadburn, 2012). However, for India, it has been listed as both native and introduced and in some cases it is listed as invasive (see distribution table for details; Reddy, 2008; Chandra et al., 2012). I. trita is also present in much of tropical America and the West Indies but its origin here is uncertain. It has been introduced into the Middle East (ILDIS, 2014; USDA-ARS, 2014). 

Distribution Table

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Risk of Introduction

The risk of introduction of I. trita is moderate to high. This species has been moved throughout the tropics to be used as an ornamental, forage, groundcover and medicinal herb. Thus, the risk of new introduction as well as the probability of escape from cultivation remains high mainly in disturbed areas and agricultural lands where seeds can be dispersed by humans, as a contaminant in soil or in mud adhered to machinery and vehicles (PROTA, 2014). 

Habitat

I. trita grows as a weed in grassy areas, scrublands, wastelands, savanna and open forests. It also occurs in secondary forests, forest edges and disturbed ground and is often invasive (Chadburn, 2012). In Australia, it is found on cracking clay, rich loamy or sandy soils on open plains or amongst rocks of various types on hills (Wilson and Rowe, 2008). In Africa, it grows as a weed of disturbed ground, gallery forest, waste ground, woodland, savanna, forest edges, stony places, and deciduous bushland (PROTA, 2014). 

Habitat List

Biology and Ecology

Genetics

The chromosome number reported for I. trita is 2n = 16 (Pandit and Kulkami, 1983).

Reproductive Biology and Phenology

In India, this species has been reported flowering from July to September (Reddy, 2008). In Australia, it flowers from January or March until May, or from September to November (Western Australian Herbarium, 2014).

Environmental Requirements

I. trita is adapted to grow on clay, sandy or loamy soils over limestone or sandstone on soils with reduced water holding capacities (Western Australian Herbarium, 2014). 

Climate

Soil Tolerances

Soil drainage

• free

Soil reaction

• acid
• neutral

Soil texture

• light
• medium

Means of Movement and Dispersal

I. trita spreads by seeds. Seeds can be actively dispersed by humans, but also secondarily dispersed as a contaminant in soil or in mud adhered to machinery and vehicles (PROTA, 2014). 

Pathway Causes

Pathway Vectors

Impact Summary

Environmental Impact

I. trita is considered weedy and invasive even in areas located within its native distribution range such as Africa and India (Reddy, 2008; Chandra, 2012). The weedy behaviour of this species allows it to rapidly colonize new areas principally in disturbed and ruderal sites (PROTA, 2014).

Risk and Impact Factors

• Proved invasive outside its native range
• Has a broad native range
• Abundant in its native range
• Highly adaptable to different environments
• Is a habitat generalist
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Pioneering in disturbed areas
• Highly mobile locally
• Benefits from human association (i.e. it is a human commensal)
• Fast growing

• Altered trophic level
• Conflict
• Damaged ecosystem services
• Ecosystem change/ habitat alteration
• Modification of nutrient regime
• Modification of successional patterns
• Monoculture formation
• Reduced native biodiversity
• Threat to/ loss of native species

• Competition - monopolizing resources
• Rapid growth

• Highly likely to be transported internationally accidentally

Uses

I. trita is used as a forage and ground cover plant in several African countries (e.g. Zimbabwe and Kenya). The seeds are used to make a nutrient rich tonic in India. Antimicrobial properties which might be associated with the presence of phenolic compounds, flavonoids, tannins, glycosides, saponins, phytosterols and alkaloids have been reported for I. trita (Kumar et al., 2013). Across the tropics it is often used as an ornamental (PROTA, 2014; USDA-ARS, 2014). 

Uses List

Animal feed, fodder, forage

• Forage

Drugs, stimulants, social uses

• Stimulants

Environmental

• Agroforestry
• Erosion control or dune stabilization

Medicinal, pharmaceutical

• Traditional/folklore

Ornamental

• Cut flower
• Seed trade

References

Acevedo-Rodríguez P; Strong MT, 2012. Catalogue of the Seed Plants of the West Indies. Smithsonian Contributions to Botany, 98:1192 pp. Washington DC, USA: Smithsonian Institution. http://botany.si.edu/Antilles/WestIndies/catalog.htm

Acevedo-Rodríguez P; Strong MT, 2014. Flora of the West Indies website: Catalogue of the Seed Plants of the West Indies. Washington DC, USA: Smithsonian Institution. http://botany.si.edu/antilles/WestIndies/catalog.htm

Chandra SK, 2012. Invasive Alien Plants of Indian Himalayan Region- Diversity and Implication. American Journal of Plant Sciences, 3:177-184.

Chauhan V; Pandey AK, 2015. A revision of trifoliolate Indigofera (Tribe Indigofereae: Fabaceae) in India. Phytotaxa, 220(1). http://dx.doi.org/10.11646/phytotaxa.220.1.1

Flora of China Editorial Committee, 2014. Flora of China. St. Louis, Missouri and Cambridge, Massachusetts, USA: Missouri Botanical Garden and Harvard University Herbaria. http://www.efloras.org/flora_page.aspx?flora_id=2

ILDIS, 2014. International Legume Database and Information Service. Reading, UK: School of Plant Sciences, University of Reading. http://www.ildis.org/

Kairo M; Ali B; Cheesman O; Haysom K; Murphy S, 2003. Invasive species threats in the Caribbean region. Report to the Nature Conservancy. Curepe, Trinidad and Tobago: CAB International, 132 pp. http://www.issg.org/database/species/reference_files/Kairo%20et%20al,%202003.pdf

Kumar RS; Kannaiyan Moorthy; Raja Vinodhini; Thambidurai Punitha, 2013. Antimicrobial efficacy and phytochemical analysis of Indigofera trita Linn. African Journal of Traditional, Complementary and Alternative Medicines, 10(3):518-525. http://journals.sfu.ca/africanem/index.php/ajtcam/index

Pandit HM; Kulkarni AR, 1983. Karyomorphology of five species of Indigofera Linn. Journal of Cytological Genetics, 18:72-78.

PROTA, 2014. PROTA4U web database. Grubben GJH, Denton OA, eds. Wageningen, Netherlands: Plant Resources of Tropical Africa. http://www.prota4u.org/search.asp

Randall RP, 2012. A Global Compendium of Weeds. Perth, Australia: Department of Agriculture and Food Western Australia, 1124 pp. http://www.cabi.org/isc/FullTextPDF/2013/20133109119.pdf

Reddy CS, 2008. Catalogue of invasive alien flora of India. Life Science Journal, 5:84-89.

Stevens PF, 2012. Angiosperm Phylogeny Website. http://www.mobot.org/MOBOT/research/APweb/

USDA-ARS, 2014. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch.aspx

USDA-NRCS, 2014. The PLANTS Database. Baton Rouge, USA: National Plant Data Center. http://plants.usda.gov/

Western Australian Herbarium, 2014. FloraBase - the Western Australian Flora. FloraBase - the Western Australian Flora., Australia: Department of Parks and Wildlife, Western Australia. http://florabase.dpaw.wa.gov.au/

Wilson PG; Rowe R, 2008. A revision of the Indigofereae (Fabaceae) in Australia. 2. Indigofera species with trifoliolate and alternately pinnate leaves. Telopea, 12(2):293-307. http://plantnet.rbgsyd.nsw.gov.au/Telopea

Wunderlin RP; Hansen BF, 2008. Atlas of Florida Vascular Plants. Tampa, Florida, USA: University of South Florida. http://www.plantatlas.usf.edu/

Links to Websites

Contributors

25/11/14 Original text by:

Julissa Rojas-Sandoval, Department of Botany-Smithsonian NMNH, Washington DC, USA

Pedro Acevedo-Rodríguez, Department of Botany-Smithsonian NMNH, Washington DC, USA

Distribution Maps