Indigofera trita
(Asian indigo)

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

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

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.

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). 

Soil drainage

• free

Soil reaction

• acid
• neutral

Soil texture

• light
• medium

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). 

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).

• 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

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).