''Lablab purpureus'' is a species of
bean
A bean is the seed of some plants in the legume family (Fabaceae) used as a vegetable for human consumption or animal feed. The seeds are often preserved through drying (a ''pulse''), but fresh beans are also sold. Dried beans are traditi ...
in the family
Fabaceae
Fabaceae () or Leguminosae,[International Code of Nomen ...](_blank)
. It is native to sub-Saharan Africa and it is cultivated throughout the
tropics
The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...
for food.
[''Lablab purpureus''.]
Tropical Forages. English language
English is a West Germanic language that developed in early medieval England and has since become a English as a lingua franca, global lingua franca. The namesake of the language is the Angles (tribe), Angles, one of the Germanic peoples th ...
common names include hyacinth bean, lablab-bean bonavist bean/pea, dolichos bean, seim or sem bean, lablab bean, Egyptian kidney bean, Indian bean, bataw and Australian pea.[''Lablab purpureus'' L. (Sweet).]
University of Agricultural Sciences, Bangalore, India. ''Lablab'' is a monotypic genus
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...
.[
]
Taxonomy
The name ''lablab'' which is also capitalized as its genus name is given by Robert Sweet from the previous name of '' Dolichos lablab'' by Carl Linnaeus
Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...
, its epithet comes from .
Subspecific classification
According to the British biologist and taxonomist Bernard Verdcourt,
:there are two cultivated subspecies of ''Lablab purpureus'' (L.) Sweet:
:* ''Lablab purpureus'' subsp. ''bengalensis'' (Jacq.) Verdc. (Syn.: ''Dolichos bengalensis'' Jacq., ''Dolichos lablab'' subsp. ''bengalensis'' (Jacq.) Rivals, ''Lablab niger'' subsp. ''bengalensis'' (Jacq.) Cuf.)
:* ''Lablab purpureus'' subsp. ''purpureus''
:in addition to one wild subspecies:
:* ''Lablab purpureus'' subsp. ''uncinatus''
:of which a special variant with lobed leaflets exists only in Namibia:
:* ''Lablab purpureus'' var. ''rhomboïdeus'' (Schinz).
Description
The plant is variable due to extensive breeding in cultivation, but in general, they are annual or short-lived perennial
In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...
vine
A vine is any plant with a growth habit of trailing or scandent (that is, climbing) stems, lianas, or runners. The word ''vine'' can also refer to such stems or runners themselves, for instance, when used in wicker work.Jackson; Benjamin; Da ...
s. The wild species is perennial. The thick stems can reach in length. The leaves are made up of three pointed leaflets, each up to long. They may be hairy on the undersides. The inflorescence
In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...
is made up of raceme
A raceme () or racemoid is an unbranched, indeterminate growth, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are ...
s of many flowers. Some cultivar
A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...
s have white flowers, and others may have purplish or blue.[
The fruit is a ]legume
Legumes are plants in the pea family Fabaceae (or Leguminosae), or the fruit or seeds of such plants. When used as a dry grain for human consumption, the seeds are also called pulses. Legumes are grown agriculturally, primarily for human consum ...
pod variable in shape, size, and color. It is usually several centimeters long and bright purple to pale green.[''Dolichos lablab''.]
Floridata. It contains up to four seeds. Depending on the cultivar, the seeds are white, brown, red, or black, sometimes with a white hilum. Wild plants have mottled seeds. The seed is about a centimeter long.[
]
Origin and occurrence
The exact origin of the lablab bean remains uncertain. Evidence of wild varieties in eastern and southern Africa
Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...
suggests these regions as the likely source, although some theories suggest India
India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
as the origin.[USDA NRCS. "Plant Guide for Lablab (Lablab purpureus)." USDA Natural Resources Conservation Service, October 2007, https://plants.usda.gov/DocumentLibrary/plantguide/pdf/pg_lapu6.pdf.]
Over the centuries, the lablab has been distributed all over the world. Despite its preference for tropical and subtropical climates, it can be found in temperate climates such as Central and South America or Italy
Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...
. Its adaptability to different climates increases its agricultural value.
Agronomy
The lablab bean remains most widespread in tropical and subtropical areas, particularly in eastern and southern Africa and India. There, the legume is grown primarily for food and fodder, but its cultivation has declined sharply in many regions of Africa, despite renewed interest in its soil-improving functions in multiple cropping systems. One of the main reasons for this decline is the replacement of faba bean by the common bean, but factors such as the many processing steps and antinutritional factors may also have played a role. In addition, lablab is often grown in home garden systems or mixed cropping systems, such as in Southeast Asia, making estimates of global production difficult.
Growing requirements
Lablab can grow on a wide range of soils, from sand to clay, within a pH range of 4.5 to 7.5. It is known to grow better in acidic conditions than most legumes, but does not grow well in poorly drained soils or in saline conditions. Average daily temperatures of 18-30°C and annual rainfall of 700-3000 mm allow lablab cultivation. However, it can tolerate temperatures as low as 4°C for short periods. The seedlings grow slowly, but once established they compete well with weeds and are able to tolerate drought or shade. Lablab requires well-drained soils as it is very intolerant of waterlogged or flooded conditions.
Cultivation, harvest and storage
As there is a high degree of variability in phenotypes, including relative maturity, yield, susceptibility to insect attack and drought resistance, cultivation can vary accordingly depending on the accession and environmental factors However, when lablab is first planted in a field, it is beneficial to inoculate the seeds with specialised rhizobium bacteria. The seeds are either broadcast and then covered, or sown to a depth of 5 cm using the drillseed technique. The seedbed must be kept free of weeds in the early stages of growth, as the young plant succumbs easily to weed pressure.
It is generally accepted that harvesting fodder crops at the transition between the vegetative and reproductive stages gives the best compromise between yield and quality, as after this stage they become higher in fibre and lignin content and lower in protein content, leading to reduced digestibility and acceptability to livestock.
When lablab is stored as hay, the main challenge is the loss of dry matter from the leaves. Farmers suggest grinding it and storing it in bags. This can also prevent damage from direct sunlight or rain.
Soil improvements
Due to its symbiosis with nitrogen-fixing rhizobium bacteria, lablab bean has low soil fertility requirements and can be an important part of an agricultural system that improves soil nitrogen availability. The rate of nitrogen fixation has been shown to be highest when combined with phosphorus fertilisation, as phosphorus is required for rhizobium attachment to roots. Its cultivation also increases potassium and phosphorus availability. These soil-improving properties make lablab attractive for intercropping, mixed cropping systems and as a green manure. For example, intercropping lablab maize can improve multiple soil functions, including microbial diversity, with minimal to no loss of maize yield.
Breeding
Researchers suggest that the wide diversity of lablab germplasm has great potential for advancing the species as a promising alternative crop through selection and breeding.
Currently, most of the traditional cultivars grown have indeterminate growth habit, which has allowed farmers to harvest plants continuously.As such varieties aren't useful in the context of modern industrial farming, there has been a push to breed varieties that develop their seeds simultaneously, allowing all the beans to be collected in a single harvest. A side-effect of these breeding efforts has been a shortened vegetative phase, which reduces yield and hence economic value Breeding objectives also differ between countries and between uses of the plants. In Australia, the focus is on creating a variety for fodder use by crossing pure line varieties with wild varieties from Africa, while researchers in Bangladesh and Africa are trying to increase the yield of existing varieties to increase their value in the food production system.
Uses
The hyacinth bean is an old domesticated pulse and multi-purpose crop. ''L. purpureus'' has been cultivated in India as early as 2500 BC.
Due to seed availability of one forage cultivar (cv. Rongai), it is often grown as forage
Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used m ...
for livestock
Livestock are the Domestication, domesticated animals that are raised in an Agriculture, agricultural setting to provide labour and produce diversified products for consumption such as meat, Egg as food, eggs, milk, fur, leather, and wool. The t ...
and as an ornamental plant
Ornamental plants or ''garden plants'' are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars th ...
. In addition, it is cited both as a medicinal plant
Medicinal plants, also called medicinal herbs, have been discovered and used in traditional medicine practices since prehistoric times. Plants synthesize hundreds of chemical compounds for various functions, including Plant defense against h ...
and a poisonous plant.[''Dolichos lablab'' (''Lablab purpureus'').]
Poisonous Plants of North Carolina. North Carolina State University
North Carolina State University (NC State, North Carolina State, NC State University, or NCSU) is a public university, public Land-grant university, land-grant research university in Raleigh, North Carolina, United States. Founded in 1887 and p ...
.
The fruit and beans are edible if boiled well with several changes of the water.[ Otherwise, they are toxic due to the presence of ]cyanogenic
In chemistry, cyanide () is an inorganic chemical compound that contains a functional group. This group, known as the cyano group, consists of a carbon atom triple-bonded to a nitrogen atom.
Salt (chemistry), Ionic cyanides contain the cyanid ...
glycosides, glycoside
In chemistry, a glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. ...
s that are converted to hydrogen cyanide
Hydrogen cyanide (formerly known as prussic acid) is a chemical compound with the chemical formula, formula HCN and structural formula . It is a highly toxic and flammable liquid that boiling, boils slightly above room temperature, at . HCN is ...
when consumed. Signs of poisoning include weakness, vomiting, shortness of breath
Shortness of breath (SOB), known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing discomfort that con ...
, twitching, stupor
Stupor is the lack of critical mental function and a level of consciousness, in which an affected person is almost entirely unresponsive and responds only to intense stimuli such as pain. The word derives from the Latin '' stupor'' ("numbness, in ...
, and convulsion
A convulsion is a medical condition where the body muscles contract and relax rapidly and repeatedly, resulting in uncontrolled shaking. Because epileptic seizures typically include convulsions, the term ''convulsion'' is often used as a synony ...
s.[ It has been shown that there is a wide range of cyanogenic potential among the varieties.
The leaves are eaten raw or cooked like ]spinach
Spinach (''Spinacia oleracea'') is a leafy green flowering plant native to Central Asia, Central and Western Asia. It is of the order Caryophyllales, family Amaranthaceae, subfamily Chenopodioideae. Its leaves are a common vegetable consumed eit ...
.[ The flowers can be eaten raw or steamed. The root can be boiled or baked for food. The seeds are used to make ]tofu
or bean curd is a food prepared by Coagulation (milk), coagulating soy milk and then pressing the resulting curds into solid white blocks of varying softness: ''silken'', ''soft'', ''firm'', and ''extra (or super) firm''. It originated in Chin ...
and tempeh.[
]
Food in South Asia
In Bangladesh
Bangladesh, officially the People's Republic of Bangladesh, is a country in South Asia. It is the List of countries and dependencies by population, eighth-most populous country in the world and among the List of countries and dependencies by ...
and West Bengal
West Bengal (; Bengali language, Bengali: , , abbr. WB) is a States and union territories of India, state in the East India, eastern portion of India. It is situated along the Bay of Bengal, along with a population of over 91 million inhabi ...
, the green pods along with the beans, known as ''sheem'' (শিম), are cooked as vegetables or cooked with fish as a curry.
In Gujarat
Gujarat () is a States of India, state along the Western India, western coast of India. Its coastline of about is the longest in the country, most of which lies on the Kathiawar peninsula. Gujarat is the List of states and union territories ...
, lablab is called . In Maharashtra, they are known as ''val papdi.'' In both states, they are commonly used to make sautéed, spiced vegetable dishes called ''sabjis''.
In Kerala
Kerala ( , ) is a States and union territories of India, state on the Malabar Coast of India. It was formed on 1 November 1956, following the passage of the States Reorganisation Act, by combining Malayalam-speaking regions of the erstwhile ...
, it is known as '', '' or ' (Malayalam
Malayalam (; , ) is a Dravidian languages, Dravidian language spoken in the Indian state of Kerala and the union territories of Lakshadweep and Puducherry (union territory), Puducherry (Mahé district) by the Malayali people. It is one of ...
: ). The beans as well as the bean pods are used in cooking curries. The bean pods are also used (along with spices) for preparing a stir-fried dish known as '.
In Tamil Nadu
Tamil Nadu (; , TN) is the southernmost States and union territories of India, state of India. The List of states and union territories of India by area, tenth largest Indian state by area and the List of states and union territories of Indi ...
, it is called ''avarai'' or ''avaraikkaay'' (Tamil: அவரைக்காய் / அவரை). The entire bean is used in cooking dry curries and in sauces/gravies such as '' sambar''. The seed alone is used in many recipes and is referred to as ''mochai'' (Tamil: மொச்சை / மொச்சைக்கொட்டை).
In Maharashtra
Maharashtra () is a state in the western peninsular region of India occupying a substantial portion of the Deccan Plateau. It is bordered by the Arabian Sea to the west, the Indian states of Karnataka and Goa to the south, Telangana to th ...
, dry preparations with green masala are often made out of these green beans (ghevda varieties; Shravan ghevda (French beans), bajirao ghevda, ghevda, walwar, pavta sheng) mostly at the end of monsoon season during fasting festivals of Shravan month.
In Karnataka
Karnataka ( ) is a States and union territories of India, state in the southwestern region of India. It was Unification of Karnataka, formed as Mysore State on 1 November 1956, with the passage of the States Reorganisation Act, 1956, States Re ...
, the hyacinth bean is made into curry (''avarekalu saaru'') (), salad (''avarekaalu usli''), added to upma (''avrekaalu uppittu''), and as a flavoring to Akki rotti. Sometimes the outer peel of the seed is removed and the inner soft part is used for a variety of dishes. This form is called ''hitakubele avarekalu'', which means "pressed (''hitaku'') hyacinth bean," and a curry known as ''hitikida avarekaalu saaru'' is made out of the deskinned beans.
In Telangana
Telangana is a States and union territories of India, state in India situated in the Southern India, south-central part of the Indian subcontinent on the high Deccan Plateau. It is the List of states and union territories of India by area, ele ...
and Andhra Pradesh
Andhra Pradesh (ISO 15919, ISO: , , AP) is a States and union territories of India, state on the East Coast of India, east coast of southern India. It is the List of states and union territories of India by area, seventh-largest state and th ...
, the bean pods are cut into small pieces and cooked as a spicy curry in the Pongal festival season. Sometimes the outer peel of the seed when tender and soaked overnight is removed and the inner soft part is used for a variety of dishes. This form is called ''pitakapappu hanupa/anapa'', which means "pressed (''pitaku'') hyacinth bean, and a curry known as pitikina anapaginjala chaaru/pitaka pappu is made from the deskinned beans and eaten along with ''bajra'' bread.
Food in Southeast and East Asia
In Myanmar, lablab beans are used to make a braised Burmese curry ''hnat'' (). They are also crisp-fried and served in Burmese pickled tea leaf salad.
In Huế
Huế (formerly Thừa Thiên Huế province) is the southernmost coastal Municipalities of Vietnam, city in the North Central Coast region, the Central Vietnam, Central of Vietnam, approximately in the center of the country. It borders Quảng ...
, Vietnam
Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...
, hyacinth beans are the main ingredient of the dish ''chè đậu ván'' (Hyacinth Bean Sweet Soup).
In China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
, the seeds are known as ''Bai Bian Dou''. They are usually dried and baked before being used in traditional Chinese herbal remedies to strengthen the spleen, reduce heat and dampness, and promote appetite.
Food tradition in East Africa
In Kenya
Kenya, officially the Republic of Kenya, is a country located in East Africa. With an estimated population of more than 52.4 million as of mid-2024, Kenya is the 27th-most-populous country in the world and the 7th most populous in Africa. ...
, the bean, known as ''njahe'' or ''njahi'', is popular among several communities, especially the Kikuyu. Seasons were actually based on it, i.e., the Season of Njahe ( Kīmera kīa njahī). It is thought to encourage lactation and has historically been the main dish for breastfeeding mothers. Beans are boiled and mashed with ripe and/or semi-ripe bananas, giving the dish a sweet taste. Today the production is in decline in eastern Africa. This is partly attributed to the fact that under colonial rule in Kenya, farmers were forced to give up their local bean in order to produce common beans (''Phaseolus vulgaris
''Phaseolus vulgaris'', the common bean,, is a herbaceous annual plant grown worldwide for its edible dry seeds or green, unripe pods. Its leaf is also occasionally used as a vegetable and the straw as fodder. Its botanical classification, alo ...
'') for export.[
]
Medicinal use
Taiwanese researchers found that a carbohydrate-binding protein (i.e. a legume lectin) from lablab beans effectively blocks the infections of influenza viruses and SARS-CoV-2. Researchers from Finland and USA found that extracts from chewing gum manufactured from lablab bean seeds had broad-spectrum anti-viral properties, likely due to the binding action of Flt3 Receptor Interacting Lectin (FRIL) on viruses; the anti-viral effect was similar to that of purified FRIL.
Gallery
File:BCBG lablab purpureus 02.jpg, Foliage
File:Lablab purpureus.JPG, Flowers
Image:Lablab purpureus Steve Hurst 1.jpg, Seeds
Further reading
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References
Sources
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External links
Dolichos bean, ''Lablab purpureus'' (L.) Sweet
by the University of Agricultural Sciences, Bangalore, India
*
JSTOR Global Plants: ''Lablab purpureus''
{{Taxonbar, from=Q1077410
Phaseoleae
Monotypic Fabaceae genera
Edible legumes
Flora of the Maldives
Forages
Nitrogen-fixing crops
Tropical agriculture
Taxa named by Carl Linnaeus
Plants described in 1763
Flora of India (region)
Flora of the Afrotropical realm
sa:निष्पावः