Abutilon indicum (country mallow)

Abutilon is a genus of herbs, subshrubs, shrubs, or small trees of about 200 species, mostly in tropical and subtropical regions (Flora of China Editorial Committee, 2015). The common names for Abutilon indicum that are most used are country mallow, and for India Kanghi (Hindi) and Atibala (Sanskrit). The species may be truly native to India (PROTA, 2015), hence another widely used name of Indian mallow or Indian abutilon.

A. indicum is a common weed, found in open, sunny and warm areas, from sea level to ca. 1600 m altitude. It is listed as an invasive mostly in Asia and Oceania (PIER, 2015; PROTA, 2015). It is not considered a threat at high elevations (PIER, 2015). The species is used widely in its native range as a traditional medicinal plant (Mohite et al, 2012; Vadnere Gautam et al., 2013), and was probably introduced for cultivation outside its native range for medicinal purposes. For some of the countries where it is reported as invasive, it is also listed as cultivated, making it probable that the species escaped from cultivation into suitable habitats, as it is listed as found in disturbed areas near dwellings and roadsides (PIER, 2015). No published details are available about the extent of invasiveness or the impacts of the species in the regions where it is reported as invasive. 

The following description is from Flora of China Editorial Committee (2015):

Herbs to subshrubs, annual or perennial, erect, many branched, 1-2.5 m, entire plant gray puberulent. Stipules subulate, 1-2 mm, curved outward; petiole 2-4 cm, gray puberulent and sparsely hairy, hairs silky, ca. 1 mm; leaf blades ovate-orbicular or nearly orbicular, 3-9 × 2.5-7 cm, densely gray stellate puberulent, base cordate, margin irregularly serrate, apex acute or acuminate. Flowers solitary, axillary, 2-2.5 cm in diam. Pedicel ca. 4 cm, articulate near apex, gray stellate puberulent. Calyx green, disk-shaped, 6-10 mm in diam., densely gray puberulent, lobes 5, broadly ovate, apex acute. Corolla uniformly yellow; petals 7-8 mm. Staminal column stellate scabrous. Ovary 15-20-loculed. Fruit black, flat topped, ca. 1.5 cm in diam.; mericarps 15-20, apex acute, slightly awned, long stellate scabrous. Seeds reniform, sparsely stellate.

A. indicum is distributed mainly in the tropics, subtropics and into warm temperate areas of the New and Old Worlds; from sea level to about 1600 m elevation (PROTA, 2015). It is reported to be native to Africa, Asia and Australasia, although it has been argued to be truly native only to Asia (PROTA, 2015). It has also been reported to be native in some countries of the New World (Esteves and Takeuchi, 2015; Missouri Botanical Garden, 2015; USDA-NRCS, 2015). 

A. indicum was probably introduced into the Americas in the 1800’s or early 1900’s (Lagerheim, 1891; Royal Botanical Gardens, Kew, 1893; Hasherger 1903; Arthur and Johnston, 1918; Missouri Botanical Garden, 2015), although it is sometimes listed as native for some of the countries of this region. For the West Indies it is reported as introduced in the early 1800’s, but in some databases is also reported as native for some of the islands. It is reported as invasive for Cuba (Oviedo-Prieto et al., 2012). The region where A. indicum is most listed as an invasive is Oceania, on Kiribati, Guam, French Polynesia, the US Minor Outlying Islands and Fiji. For some of these islands the species is also reported as cultivated. Although it is reported as invasive for Hawaii, it is noted as mainly cultivated and occasionally naturalized (PIER, 2015).

There is almost no information available on how A. indicum was introduced to various regions or how it has spread. Since it has been used extensively in ethnobotany for centuries in its native range, it can be assumed it was mainly introduced into other areas as a medicinal plant, as it is reported to be used by natives in countries outside its probable original range (Mitchell, 1982; Mohite et al., 2013; PIER 2015). Also outside its native range, there are reports of the use of its fibres for rope-making (Maiti and Chakravarty, 1977; Fuentes Fiallo, 1999; Brussell, 2004). 

The species is sold over the internet and in nurseries as an ornamental. Although there is almost no documented information on the impact of A. indicum at introduced sites, caution should be exerted until more information is available on the invasiveness of the species.

Leaf residue extracts of A. indicum have been evaluated for their effect on the germination and growth of the wheat cultivars, Sind-81, Sind-83 and Sarsabz, and chickpea cv. CM-72. The extracts did not inhibit germination, but stimulated the shoot length of all the cultivars. Root inhibition was found for all, except Sind-81 and chickpea (Alam and Azmi, 1990). 

A. indicum, A. abutiloides and A. hirtum are all found in similar habitats and have similar growth forms. Abutilon abutiloides has 5-7 mericarps (segments in the fruit), while A. hirtum and A. indicum have 15-25 mericarps. A. hirtum has an orange corolla with a purple centre, while A. indicum has a uniformly yellow corolla (Flora of China Editorial Committee, 2015). 

A. indicum is found in open, ruderal places in the tropics and subtropics. Reported from roadsides, low bushes, savannas, lakesides, beaches, dunes and roadsides (PROTA, 2015). It is reported near dwellings, disturbed sites and roadsides in some of the countries where it is listed as invasive (Mohite et al., 2013; PIER 2015). Tolerates droughts (PROTA, 2015) and saline environments (Allaway et al., 1984). 

A. indicum is one of the host plants for the moths Earias insulana and E. vitella, which are considered as pests of cotton and okra plants (Saini and Singh, 1999; Syed et al., 2011). The species is reported to become heavily infested by mealybugs (Coccidohystrix sp.) in India (Hayat et al. 2007). Hexomyza abutilonicaulis, Urentius euonymus and Trachys herillus are reported in Pakistan as natural insect enemies of the genus Abutilon (Commonwealth Institute of Biological Control Pakistan Station, 1980; Pajni and Nanda, 1992). 

In India, A. indicum is one of the hosts for the red cotton bug, Dysdercus koeniggii, which is considered to be a minor pest on cotton, eggplant, okra and Hibiscus (Wadnerkar et al., 1979). A. indicum plants infested with Earias insulana and E. vitella near cotton fields could carry the infestation into the crops (Saini and Singh, 1999; Syed et al., 2011).

Mohite et al. (2012) and Vadnere Gautam et al. (2013) give detailed reviews on the microscopic, phytochemical and pharmacological properties and uses of A. indicum. This includes: hepatoprotective, wound healing, immunomodulatory, analgesic, antimalarial, antimicrobial and hypoglycemic activity, among others. Almost all the parts of this plant are documented as being used. It is used by natives of India, Malaysia, the Philippines and Indochina. In India it is also reported as used by the Santals tribe to treat convulsions, cramps, colic pain, spermatorrhoea, dysentery, tuberculosis, coughs, bronchitis and menorrhagia in humans and bone fracture in cattle (Jain and Tarafder, 1970). Similar uses are reported for the Nicobarese tribe in India (Dagar and Dagar, 1991). Mathur and Sundaramoorthy (2013) report 18 pharmacological properties and nine body systems treated by the use of this species. Seetharam et al. (2002) report that extracts from A. indicum administered to rats stimulate insulin production causing blood glucose levels to drop. Men in Gujrat, India use the species as an aphrodisiac (Prabhuji et al., 2010). A. indicum is one of the sources of the drug “Bala”, sold in markets in India and used in the Ayurvedic system of medicine to treat various ailments (Deokule and Patale, 2002).

Due to its importance as a medicinal plant in India, studies had been made on A. indicum to establish the protocols for regenerating large number of plantlets in vitro from leaf derived callus cultures. These protocols are the first steps to establish large scale propagation of this species (Rout et al., 2009). In Pakistan, where rearing livestock accounts for 30-40% of income, A. indicum is one of the native species suggested for planting and/or reseeding to improve grazing lands for goats and sheep (Rafiq et al., 2010).

In Australia, A. indicum is used as food, timber and reported to have demulcent properties (Mitchell, 1982). It is also used for its fibres in various countries (Maiti and Chakravarty, 1977; Fuentes Fiallo, 1999; Brussell, 2004).

A. indicum has been studied for the development of botanical pesticides and extracts from the leaves are a feeding deterrent to the tomato fruit borer, Helicoverpa armigera (Elumalai et al., 2008). Prabhuji et al. (2010) report a steroidal compound isolated from the stems of A. indicum with fungicidal and fungistatic properties against various Aspergillus species.

Mathur and Sundaramoorthy (2013) assessed the economic impact and conservation priorities of 123 medicinal plants from the Thar Desert in India. For A. indicum they reported the species not being in cultivation and being highly harvested from the wild due to its medicinal importance. They propose that the species needs to have an immediate conservation priority.

Social Benefit

In India where fluoride contamination related diseases occur in near to 62 million people, A. indicum stems are used to prepare nitric acid activated carbon to remove fluoride ions from contaminated water (Suneetha et al., 2014).

Environmental Services

A. indicum has been suggested as a potential candidate species to be used for the phytoremediation of heavy metal-contaminated soils (Varum et al., 2015).

A. indicum is reported as one of the plants which the nymphs of Aularches miliaris feed on. Although this grasshopper is reported as a pest for some crops, it is also listed as a near-threatened species in South India and its conservation is recommended (Josephrajkimar et al., 2011).

Rahuman et al. (2008) tested the larvicidal activity on Culex quinquefasciatus and found high larval mortality when using petroleum ether extract from A. indicum. They also report the presence of β-sitosterol for A. indicum as a new natural mosquito larvicidal agent. Hexane leaf extracts are reported to be effective against the larvae of Aedes aegypti (Tennyson et al., 2012). Previous studies in Thailand showed that A. indicum extracts show potential larval toxicity for Aedes aegyptii and high toxicity to guppy fishes (Promsiri et al., 2006).

Most of the information available on A. indicum is related to its pharmacological properties, its phytochemistry or the ethnobotanical uses. Although literature reports it as a weed and/or as invasive for some countries or regions, not much information is available about its negative impacts. No information is available on the impacts on the native species or the habitats where it is reported as invasive. On the contrary, it is reported as being threatened because it is over-harvested in some countries. There is also conflicting information about it being native or introduced for some countries, as it is listed as both in different sources for a country. Information about the environmental requirements, reproductive biology, habitats and impacts is scarce or lacking, and needed for a thoughtful evaluation of the invasiveness of the species.