The
pigeon pea also known as
tropical green pea,
toor dāl or
arhar dāl (
IndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
),
ತೊಗರಿ ಬೇಳೆ (Kannada)
kadios (
PhilippinesThe Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
), or
Congo pea or
gungo pea (in
JamaicaJamaica is an island nation of the Greater Antilles, in length, up to in width and 10,990 square kilometres in area. It is situated in the Caribbean Sea, about south of Cuba, and west of Hispaniola, the island harbouring the nation-states Haiti and the Dominican Republic...
),
pois Congo (in HaitiHaiti , officially the Republic of Haiti , is a Caribbean country. It occupies the western, smaller portion of the island of Hispaniola, in the Greater Antillean archipelago, which it shares with the Dominican Republic. Ayiti was the indigenous Taíno or Amerindian name for the island...
), gandul
(in Puerto RicoPuerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...
), gunga pea, or
no-eye pea, [
Cajanus cajan, synonyms
Cajanus indicus Spreng. (Valder 1895) and
Cytisus cajan (Crawfurd 1852)] is a perennial member of the
familyIn biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
FabaceaeThe Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...
. Pigeonpea also happens to be the first seed legume plant to have complete genome sequence.
Origins
The cultivation of the pigeon pea goes back at least 3500 years. The centre of origin is the eastern part of peninsular India, including the state of
OrissaOrissa , officially Odisha since Nov 2011, is a state of India, located on the east coast of India, by the Bay of Bengal. It is the modern name of the ancient nation of Kalinga, which was invaded by the Maurya Emperor Ashoka in 261 BC. The modern state of Orissa was established on 1 April...
, where the closest wild relatives (
Cajanus cajanifolia) occur in tropical deciduous woodlands. Archaeological finds of pigeonpea include those from two Neolithic sites in Orissa, Gopalpur and Golbai Sassan dating between 3400 and 3000 years ago, and sites in South India, Sanganakallu and Tuljapur Garhi, also dating back to 3400 years ago . From India it traveled to
East AfricaEast Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...
and
West AfricaWest Africa or Western Africa is the westernmost region of the African continent. Geopolitically, the UN definition of Western Africa includes the following 16 countries and an area of approximately 5 million square km:-Flags of West Africa:...
. There is was first encountered by Europeans, so it obtained the name Congo Pea. By means of the slave trade it came to the American continent, probably in the 17th century .
Cultivation
Today, pigeon peas are widely cultivated in all tropical and semitropical regions of both the
OldThe Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....
and the New Worlds. Pigeon peas can be of a perennial variety, in which the crop can last three to five years (although the seed yield drops considerably after the first two years), or an annual variety more suitable for seed production.
Pigeon peas are an important
legume crop of rainfed agriculture in the semiarid tropics. The
Indian subcontinentThe Indian subcontinent, also Indian Subcontinent, Indo-Pak Subcontinent or South Asian Subcontinent is a region of the Asian continent on the Indian tectonic plate from the Hindu Kush or Hindu Koh, Himalayas and including the Kuen Lun and Karakoram ranges, forming a land mass which extends...
, Eastern Africa and
Central AmericaCentral America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
, in that order, are the world's three main pigeon pea-producing regions. Pigeon peas are cultivated in more than 25 tropical and subtropical countries, either as a sole crop or intermixed with
cerealCereals are grasses cultivated for the edible components of their grain , composed of the endosperm, germ, and bran...
s, such as
sorghumSorghum is a genus of numerous species of grasses, one of which is raised for grain and many of which are used as fodder plants either cultivated or as part of pasture. The plants are cultivated in warmer climates worldwide. Species are native to tropical and subtropical regions of all continents...
(
Sorghum bicolor),
pearl milletPearl millet is the most widely grown type of millet. Grown in Africa and the Indian subcontinent since prehistoric times, it is generally accepted that pearl millet originated in Africa and was subsequently introduced into India. The center of diversity, and suggested area of domestication, for...
(
Pennisetium glaucum), or
maizeMaize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...
(
Zea mays), or with other legumes, such as
peanutThe peanut, or groundnut , is a species in the legume or "bean" family , so it is not a nut. The peanut was probably first cultivated in the valleys of Peru. It is an annual herbaceous plant growing tall...
s (
Arachis hypogaea). Being a legume, the pigeon pea enriches soil through symbiotic
nitrogen fixationNitrogen fixation is the natural process, either biological or abiotic, by which nitrogen in the atmosphere is converted into ammonia . This process is essential for life because fixed nitrogen is required to biosynthesize the basic building blocks of life, e.g., nucleotides for DNA and RNA and...
.
The crop is cultivated on marginal land by resource-poor farmers, who commonly grow traditional medium- and long-duration (5–11 months)
landraceA landrace is a local variety of a domesticated animal or plant species which has developed largely by natural processes, by adaptation to the natural and cultural environment in which it lives. It differs from a formal breed which has been bred deliberately to conform to a particular standard...
s. Short-duration pigeon peas (3–4 months) suitable for multiple cropping have recently been developed. Traditionally, the use of such input as fertilizers, weeding, irrigation, and pesticides is minimal, so present yield levels are low (average = 700 kg/ha). Greater attention is now being given to managing the crop because it is in high demand at remunerative prices.
Pigeon peas are very drought resistant, so can be grown in areas with less than 650 mm annual rainfall.
World production of pigeon peas is estimated at 46,000 km
2. About 82% of this is grown in
IndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
. These days it is the most essential ingredient of animal feed used in West Africa, most especially in Nigeria, where it is also grown.
Uses
Pigeon peas are both a food crop (dried peas, flour, or green vegetable peas) and a forage/cover crop. They contain high levels of
proteinProteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
and the important
amino acidAmino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
s
methionineMethionine is an α-amino acid with the chemical formula HO2CCHCH2CH2SCH3. This essential amino acid is classified as nonpolar. This amino-acid is coded by the codon AUG, also known as the initiation codon, since it indicates mRNA's coding region where translation into protein...
,
lysineLysine is an α-amino acid with the chemical formula HO2CCH4NH2. It is an essential amino acid, which means that the human body cannot synthesize it. Its codons are AAA and AAG....
, and
tryptophanTryptophan is one of the 20 standard amino acids, as well as an essential amino acid in the human diet. It is encoded in the standard genetic code as the codon UGG...
. In combination with cereals, pigeon peas make a well-balanced human food. The dried peas may be sprouted briefly, then cooked, for a flavor different from the green or dried peas. Sprouting also enhances the digestibility of dried pigeon peas via the reduction of indigestible sugars that would otherwise remain in the cooked dried peas.
In
IndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
, split pigeon peas (
toor dalDal is a preparation of pulses which have been stripped of their outer hulls and split. It also refers to the thick stew prepared from these, an important part of Indian, Nepali, Pakistani, Sri Lankan, and Bangladeshi cuisine...
) are one of the most popular pulses, being an important source of protein in a mostly vegetarian diet. In regions where it grows, fresh young pods are eaten as a vegetable in dishes such as
sambar. In
EthiopiaEthiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2...
, not only the pods, but also the young shoots and leaves are cooked and eaten.
In some places, such as the
Dominican RepublicThe Dominican Republic is a nation on the island of La Hispaniola, part of the Greater Antilles archipelago in the Caribbean region. The western third of the island is occupied by the nation of Haiti, making Hispaniola one of two Caribbean islands that are shared by two countries...
and
HawaiiHawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
, pigeon peas are grown for canning and consumption. A dish made of rice and green pigeon peas (called
moro de guandules) is a traditional food in Dominican Republic. Pigeon peas are also made as a stew, with
plantainPlantain is the common name for herbaceous plants of the genus Musa. The fruit they produce is generally used for cooking, in contrast to the soft, sweet banana...
balls. In
Puerto RicoPuerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...
arroz con gandulesArroz con gandules is a combination of rice, pigeon peas and pork, cooked in the same pot with Puerto Rican-style sofrito. This is the signature dish of Puerto Rican culture and also has become very popular throughout Latin America and the Caribbean....
is made with
riceRice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...
and pigeon peas and is a typical dish.
Trinidad and TobagoTrinidad and Tobago officially the Republic of Trinidad and Tobago is an archipelagic state in the southern Caribbean, lying just off the coast of northeastern Venezuela and south of Grenada in the Lesser Antilles...
and
GrenadaGrenada is an island country and Commonwealth Realm consisting of the island of Grenada and six smaller islands at the southern end of the Grenadines in the southeastern Caribbean Sea...
have their own variant, called
pelau, which includes either beef or chicken, and occasionally pumpkin and pieces of cured pig tail.
In
ThailandThailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
, pigeon peas are grown as a host for
scale insectThe scale insects are small insects of the order Hemiptera, generally classified as the superfamily Coccoidea. There are about 8,000 species of scale insects.-Ecology:...
s which produce
lacLac is the scarlet resinous secretion of a number of species of insects, namely some of the species of the genera Metatachardia, Laccifer, Tachordiella, Austrotacharidia, Afrotachardina, and Tachardina of the superfamily Coccoidea, of which the most commonly cultivated species is Kerria lacca.The...
.
Pigeon peas are in some areas an important crop for
green manureIn agriculture, a green manure is a type of cover crop grown primarily to add nutrients and organic matter to the soil. Typically, a green manure crop is grown for a specific period of time , and then plowed under and incorporated into the soil while green or shortly after flowering...
, providing up to 40 kg nitrogen per hectare. The woody stems of pigeon peas can also be used as firewood, fencing and thatch.
Genome Sequence
The first draft of pigeon pea genome sequence was done by a group of 31 Indian scientists from the
Indian Council of Agricultural ResearchIndian Council of Agricultural Research , New Delhi, India is an autonomous organisation under the Department of Agricultural Research and Education, Ministry of Agriculture, Government of India...
under the leadership of
Nagendra Kumar SinghDr Nagendra Kumar Singh is an eminent Indian agricultural scientist. He is presently a National Professor under ICAR at National Research Centre for Plant Biotechnology, Indian Agricultural Research Institute, New Delhi. He was born in a small village called Rajapur in the Mau District of Uttar...
. The paper is published in one of the Indian
journal.
Nature Biotechnology has published pigeonpea genome sequence led by International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) under the leadership of
Dr Rajeev K VarshneyRajeev Kumar Varshney is a geneticist currently working as Principal Scientist- Applied Genomics at International Crops Research Institute for the Semi-Arid Tropics , Patancheru, India and also Theme Leader - Comparative and Applied Genomics , , hosted at CIMMYT, Mexico.Rajeev Varshney has over 10...
through
International Initiative for Pigeonpea Genomics (IIPG).
There is controversy between the mentioned publications
Eventually, pigeonpea crop will be benefited as these two genome sequences can be merged in near future.
External links
- Crop Wild Relatives Gap Analysis Portal reliable information source on where and what to conserve ex-situ, regarding Cajanus genepool
- (http://fcit.usf.edu/florida/docs/v/veg.htm)
- (http://www.springerlink.com/content/g78774q222672082/fulltext.pdf)
- (http://www.nrcpb.org/content/nrcpb-scientists-succeeded-decoding-arhar-dal-genome)
- (http://www.icar.org.in/node/3815)
- (http://www.nature.com/nbt/journal/vaop/ncurrent/full/nbt.2022.html)
- (http://www.icrisat.org/newsroom/latest-news/happenings/happenings1492.htm#1)
- (http://www.icrisat.org/newsroom/news-releases/icrisat-pr-2011-media20.htm)