Boerhavia erecta is one of the many species that is present in the genus Boerhavia L. Commonly known as the erect spiderling or the erect boerhavia, it is a member of the Nyctaginaceae family with a chromosome number of 52. Boerhavia erecta is native to the United States, Mexico, Central America and western South America, but the erect spiderling is now present in different tropical and subtropical areas of the world. In Africa, the distribution spans from West Africa to the east of Somalia and South Africa. It has recently been introduced to the east of Madagascar in Réunion. In Asia, it is present in India, Java, Malaysia, the Philippines, China and the Ryukyu Islands. Boerhavia erecta is an extraordinary species of plant that is useful and unique through its physical characteristics and genetic composition.
Similar to Boerhavia diffusa, the erect spiderling is a perennial herb. B. erecta can be distinguished from B. diffusa because erect spiderlings are straight, contain white and pink flowers and also possess obconical (cone-like) glabrous (smooth) fruit.
They also have perennating buds near the ground surface. Most species of the B. erecta grow 60 centimetres (24 in) tall and 3–5 millimetres (0.12–0.20 in) across. The stems are often cylindrical and do not possess furrows or ridges. The stems are green with hints of purple and are covered in soft, minuscule hair. In different nodes (undifferentiated tissue) of the stem, there is fine hair and sticky bands. As you travel towards the base of the stem, it becomes glabrous and woody.
Leaves are somewhat fleshy (soft and thick) and are situated in an unequal opposite arrangement. An opposite arrangement indicates that there are two leaves per node. The largest leaf in a B. erecta plant is 3–4.5 cm (1.2–1.8 in) long and 2–3.5 cm (0.79–1.38 in) wide. The petiole on a large leaf is approximately 3 cm (1.2 in) long. A smaller leaf on the erect spiderling is 1.5–2.5 cm (0.59–0.98 in) long and 2–3.5 cm (0.79–1.38 in) wide, with a petiole less than 2 cm (0.79 in) long. The petioles of the leaf are pale green with a hint of purple. A petiole is a stalk that joins the leaf blade to the stem. The blade of the leaf is ovate, ovate- lanceolate or lanceolate. The upper portion of the leaf is green and consists of tiny hairs and may or may not be glandular dotted (consists of tiny clumps of end cells). The lower section of the leaf is grayish-white, with a slight combination of purplish red. The margins of the leaf exhibit a purplish-red color. The apex of the leaf is either acute or obtuse. The base of the leaf can be cuneate or truncate.
Boerhavia erecta plants have determinative inflorescence. This means that the central flowers open first at the time of cell division. Flowering occurs in the early summer to mid-fall. B. erecta has multiple flowers on one branch. The peduncle is sturdy at the base and the capillaries are at the apex. The peduncle is green and purple with sticky internodal bands. Each inflorescence branch contains two leafy bracts (0.3-0.5 mm), which is a modified version of a leaf that assists in attracting pollinators. The bracts detaches at an early stage and are usually linear lanceolate. Gathered at the apex of the peduncle are 2–6 sessile flowers. Each flower is a pale yellow color combined with purple. The flowers portray a narrow lanceolate shape. The whorls of the flower are bell-shaped with hairs towards the middle. The whorls are pink, 5-lobed, 1.5 mm long and 2 mm wide when it is open. There are 2-3 stamens in each flower. The filaments are white and 1 mm long. The anthers on the filament are 0.3 mm across, white and circular. The style is white and 1 mm long. The stigma is white and 0.3 mm across. Anthocarps (false fruits) are circular and flat. They are 5-ribbed (0.3-0.5 mm wide) and glabrous. The ribs have a wrinkly texture transversely and have needle- like crystals, known as raphide, that run longitudinally. The sticky fruits of this plant are dispersed by humans and animals.
Boerhavia erecta is used in production of medicine as well as food. Boerhavia erecta is found in many vegetables such as legumes and cotton. It is also found in sugar canes. In West and East Africa, the leaves are eaten as a vegetable and used in the preparation of sauces. Cattle in the Sahel, eat the leaves before flowers develop. The medicinal uses of Boerhavia erecta are similar to the species Boerhavia diffusa, because of the compound alkaloid purnarnavine. In India, the root is used as a diuretic to treat jaundice, enlarged spleen, gonorrhea and other internal inflammations. It is also used as stomachic, cardiotonic, hepatoprotective, laxative, anthelmintic (expels parasitic worms), febrifuge (reduces fever), and an expectorant. In moderate doses it is used in the treatment of asthma. In higher dosages it is used as an emetic and purgative. A decoction mash of the entire plant is used to treat gastro-intestinal, liver and infertility problems in Mali. A paste of the roots is rubbed on the skin to ripen abscesses and ulcers. In Niger, the ash is rubbed on the skin to prevent fungal infections. In Benin it is used to treat convulsions in children. In southern Sudan the roots are used to treat the base of a newly severed umbilical cord. In Kenya, people crush the leaves to and mix it with water to treat diarrhea. In Tanzania, the ash of the plant is mixed with oil to treat rheumatism and scabies. The sap that is produced in the leaves is squeezed into the eye to treat conjunctivitis.
In December, 2003 scientists in Taiwan noticed a new species growing on the railroad of Kaoshing. After a thorough investigation, they realized that it was Boerhavia erecta, a plant species that is native in the New World. B. erecta has the ability to grow in many different environments such as bushland, on waste ground, agricultural sides and by roadsides. Although they have a variety of distribution, scientists do not consider these plants to be a risk to species of plants. The International Union for Conservation of Nature, is working with countries such as Bangladesh, to create well-nourished conditions for these plants to thrive in. Further investigations will be done to reveal their pharmacological characteristics as well as elucidate the compounds that are responsible for it.
- Chen, Shih-Huei, and Ming-Jou Wu." A Taxonomical Study of the Genus Boerhavia (Nyctaginaceae) in Taiwan." Taiwania. 52.4 (2007): 332-372.http://www.tsps.org.tw/document/paper/new/076%20A%20Taxonomical%20Study%20of%20the%20Genus%20Boerhavia%20(Nyctaginaceae)%20in%20Taiwan.pdf
- USDA, NRCS. 2012. The PLANTS Database (http://plants.usda.gov, 29 June 2012). National Plant Data Team, Greensboro, NC 27401-4901 USA. http://plants.usda.gov/java/profile?symbol=BOER#
- 'eFloras (2008). http://www.efloras.org [accessed 22 February 2008]*' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
- Chou, Fu-San, Ho-Yih Liu, and Chiou-Rong Sheue. "Boerhavia erecta L. (Nyctaginaceae), A New Adventive Plant in Taiwan." Taiwania. 49.1 (2004): 39-43. MA. http://tai2.ntu.edu.tw/taiwania/pdf/tai.2004.49.1.39.pdf
- Schmelzer, G.H., 2006. Boerhavia erecta L. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). Prota 11(1): Medicinal plants/Plantes médicinales 1. [CD-Rom]. PROTA, Wageningen, Netherlands. http://database.prota.org/PROTAhtml/Boerhavia%20erecta_En.htm
- Motaleb, M. A., 2010. Approaches to Conservation of Medicinal Plants and Traditional Knowledge: A Focus on the Chittagong Hill Tracts. IUCN (International Union for Conservation of Nature), Bangladesh Country Office, Dhaka, Bangladesh, pp viii+30.http://cmsdata.iucn.org/downloads/iucn_bangladesh_medicinal_plant_approache_book.pdf