''Tropaeolum tuberosum'' (mashua, see below for other names) is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Tropaeolaceae, grown in the

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

, particularly in

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

and

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

, and to a lesser extent in

Ecuador Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ''Eku ...

as well as in some areas of

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...

, for its edible

tuber Tubers are a type of enlarged structure used as storage organs for nutrients in some plants. They are used for the plant's perennation (survival of the winter or dry months), to provide energy and nutrients for regrowth during the next growing ...

s, which are eaten cooked or roasted as a vegetable. It is a minor food source, especially to native Amerindian populations. Mashua is a

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of t ...

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

climber growing to in height. It is related to garden nasturtiums, and is occasionally cultivated as an ornamental for its brightly coloured tubular flowers.

Alternative names

This plant is commonly called mashua in Peru and Ecuador, but other names include: In Boyacá, Colombia it is also named Nabu

Agronomy

The plant grows vigorously even in marginal soils and it competes well with weeds. It is well-adapted to high-altitude

subsistence agriculture Subsistence agriculture occurs when farmers grow food crops to meet the needs of themselves and their families on smallholdings. Subsistence agriculturalists target farm output for survival and for mostly local requirements, with little or no su ...

, and gives high yields; 30 tonnes per hectare are yielded at a height of 3000 metres, but up to 70 tons per hectare have been produced under research conditions.Mashua Ethnobotanical Leaflet, Southern Illinois University
/ref> Its extraordinary resistance to insect, nematode and bacterial pests is attributed to high levels of

isothiocyanate In organic chemistry, isothiocyanate is the functional group , formed by substituting the oxygen in the isocyanate group with a sulfur. Many natural isothiocyanates from plants are produced by enzymatic conversion of metabolites called glucosinol ...

s. Although mashua is fully domesticated, it can persist in wild vegetation because of its aggressive growth and robustness. In Colombia, it is planted as a companion crop to repel pests in potato fields. alt=Tuber colored as if bleeding blood, Popular Peruvian mashua cultivar Yawar Waqay, meaning "weeping blood", left, 187x187px

Culinary Use

Raw mashua tuber is bitter due to

glucosinolates Glucosinolates are natural components of many pungency, pungent plants such as mustard plant, mustard, cabbage, and horseradish. The pungency of those plants is due to mustard oils produced from glucosinolates when the plant material is chewed, cut ...

, but the bitterness diminishes after cooking, freezing, or pounding. The tubers comprise as much as 75 percent of the mature plants by dry weight (40 percent is typical for

cereal A cereal is any Poaceae, grass cultivated for the edible components of its grain (botanically, a type of fruit called a caryopsis), composed of the endosperm, Cereal germ, germ, and bran. Cereal Grain, grain crops are grown in greater quantit ...

s). Up to 75 percent of dry matter reaches the tubercle.Peace Diaries Workspace
Popularization of mashua may be limited by its strong flavor, and its reputation as an

anaphrodisiac An anaphrodisiac (also antaphrodisiac or antiaphrodisiac) is a substance that quells or blunts the libido. It is the opposite of an aphrodisiac, something that enhances sexual appetite. The word ''anaphrodisiac'' comes from the Greek privative p ...

. Father

Bernabé Cobo Padre Bernabé Cobo (born at Lopera in Spain, 1582; died at Lima, Peru, 9 October 1657) was a Spanish Jesuit missionary and writer. He played a part in the early history of quinine by his description of cinchona bark; he brought some to Europe on ...

records that in the 16th century the

Inca The Inca Empire (also known as the Incan Empire and the Inka Empire), called ''Tawantinsuyu'' by its subjects, (Quechua for the "Realm of the Four Parts", "four parts together" ) was the largest empire in pre-Columbian America. The admin ...

used to give enormous amounts of mashua to their troops so that they would forget their wives. However, mashua tubers roasted in traditional earthen field ovens, built at harvest, are considered a delicacy. Also, the raw tubers can be shredded thinly and added to salads, to confer a spicy flavour and crunchy texture. alt=Flowering mashua plants in full bloom, Flowering mashua plants near Quito, Ecuador, 1990, 340x340px

Cultivation as an ornamental

In its native range, mashua is mainly cultivated for its edible tubers, but it has ornamental value in the temperate zone because of its trailing habit and showy, bi-coloured tubular flowers, which appear in summer and autumn. The sepals are orange-red while the petals are bright yellow. In areas prone to frost, it requires some protection in winter. The

cultivar A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, ...

''T. tuberosum'' var. ''lineamaculatum'' 'Ken Aslet' has gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (Nort ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. History The Award of Garden Merit ...

Medicinal properties

Mashua has putative

effects. It has been recorded by the Spanish chronicler Cobo that mashua was fed to their armies by the

Inca Emperors The Inca Empire (also known as the Incan Empire and the Inka Empire), called ''Tawantinsuyu'' by its subjects, (Quechua for the "Realm of the Four Parts", "four parts together" ) was the largest empire in pre-Columbian America. The admin ...

, "that they should forget their wives". Studies of male rats fed on mashua tubers have shown a 45% drop in

testosterone Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testes and prostate, as well as promoting secondar ...

levels due to the presence of

isothiocyanates In organic chemistry, isothiocyanate is the functional group , formed by substituting the oxygen in the isocyanate group with a sulfur. Many natural isothiocyanates from plants are produced by enzymatic conversion of metabolites called glucosin ...

. Mashua contains

Docosatetraenoylethanolamide Docosatetraenoylethanolamide (DEA) (Adrenoyl-ethanolamide) (Adrenoyl-EA) is an endogenous ethanolamide that has been shown to act on the cannabinoid (CB1) receptor. DEA is similar in structure to anandamide (AEA, a recognized endogenous ligand fo ...

, a cannabinoid structurally similar to Anandamide that also acts on the cannabinoid (CB₁) receptor among other structurally related compounds such as N–oleoyldopamine.

References