Pigeon pea

Thepigeon pea(Cajanus cajan) ortoor dalis a perenniallegumefrom thefamilyFabaceaenative to theEastern Hemisphere.The pigeon pea is widely cultivated in tropical and semitropical regions around the world, being commonly consumed inSouth Asia,Southeast Asia,Africa,Latin Americaand theCaribbean.
The scientific name for thegenusCajanusand thespeciescajanderive from theMalaywordkatjang(modern spelling: kacang) meaninglegumein reference to the bean of the plant.
InEnglishthey are commonly referred to aspigeon peawhich originates from the historical utilization of the pulse aspigeonfodderinBarbados.The termCongo peaandAngola peadeveloped due to the presence of its cultivation in Africa and the association of its utilization with those of African descent.The namesno-eye peaandred gramboth refer to the characteristics of the seed, withno-eye peain reference to the lack of ahilumblotch on most varieties, unlike theblack-eyed pea, andred gramin reference to the red color of most Indian varieties and gram simply referring to the plant being alegume.
InBeninthe pigeon pea is locally known asklouékouninFon,otinininEdeandekluiinAdja.InCape Verdethey are calledFixon KonguinCape Verdean creole.InComorosandMauritiusthey are known asembrevadeorambrebdadeinComorianandMorisyen, respectively, in return originating from theMalagasyterm for the plantamberivatry.InGhanathey are known asaduwaoradowainDagbani.InKenyaandTanzaniathey are known asmbaaziinSwahili.InMalawithey are callednandoloinChichewa.InNigeriapigeon peas are calledfiofioormgbụmgbụinIgbo,waken-masar"Egyptian bean"orwaken-turawa"foreigner bean"inHausa,andòtílíinYoruba.InSudanthey are known asadaseya,adasyandadasia.
InIndiathe plant is known by various different names such as
InPersian,it is known as شاخول (shakhul) and is popular in dishes.
In thePhilippinesthey are known asKadiosinFilipinoandKadyosinTagalog.
InLatin America,they are known asguandulorgandulinSpanish, andfeijão anduorganduinPortugueseall of which derive fromKikongowanduor fromKimbunduoanda; both names referring to the same plant.
In theAnglophoneregions of theCaribbean, likeJamaica,they are known asGungo peas, coming from the more archaicEnglishname for the plantcongo pea,given to the plant because of its popularity and relation toSub-Saharan Africa.
InFrancophoneregions of the Caribbean they are known aspois d' angole,pwa di bwainAntillean creoleandpwa kongoinHaitian creole.
InSurinamethey are known aswandoeorgele pesi,the former of which is derived from the same source as its Spanish and Portuguese counterparts, the latter of which literally translates to 'yellow pea' from Dutch andSranan Tongo.
InHawaiithey are known aspi pokoliko'Puerto Rican pea'  orpi nunu'pigeon pea' in theHawaiian language.
The closest relatives to the cultivated pigeon pea areCajanus cajanifolia,Cajanus scarabaeoidesandCajanus kerstingii, native to India and the latter West Africa respectively.Much debate exist over the geographical origin of the species, with some groups claiming origin from theNile riverandWestern Africa, and the other Indian origin.The two epicenters of genetic diversity exist in both Africa and India, but India is considered to be its primary center of origin with West Africa being considered a second major center of origin.
By at least 2,800 BCE in peninsular India,where its presumptive closest wild relativesCajanus cajanifoliaoccurs in tropicaldeciduous woodlands, its cultivation has been documented.Archaeological finds of pigeon pea cultivation dating to about14th century BChave also been found at theNeolithicsite ofSanganakalluinBellaryand its border areaTuljapur(where the cultivation of African domesticated plants likepearl millet,finger millet, andLablabhave also been uncovered),as well as inGopalpurand otherSouth Indian states.
From India it may have made its way toNorth-East Africavia Trans-Oceanic Bronze Age trade that allowed cross-cultural exchange of resources and agricultural products.The earliest evidence of pigeon peas in Africa was found inAncient Egyptwith the presence of seeds in Egyptian tombs dating back to around 2,200 BCE.From eastern Africa, cultivation spread further west and south through the continent, where by means of theTrans-Atlantic slave trade, it reached theAmericasaround the 17th century.
Pigeon peas were introduced to Hawaii in 1824 byJames Macraewith a few specimens becoming naturalized on the islands, but they wouldn't gain much popularity until later.By the early 20th centuryFilipinosandPuerto Ricansbegan to emigrate from theAmerican PhilippinesandPuerto RicotoHawaiito work insugarcane plantationsin 1906 and 1901, respectively.Pigeon peas are said to have been popularized on the island by the Puerto Rican community where by theFirst World Wartheir cultivation began, to expand on the island where they are still cultivated and consumed by locals.
Pigeon peas contain high levels ofproteinand the importantamino acidsmethionine,lysine, andtryptophan.
The following table indicates completeness of nutritional profile of various amino acids within mature seeds of pigeon pea.
Methionine + Cystine combination is the only limiting amino acid combination in pigeon pea. In contrast to the mature seeds, the immature seeds are generally lower in all nutritional values, however they contain a significant amount of vitamin C (39 mg per 100 g serving) and have a slightly higher fat content. Research has shown that the protein content of the immature seeds is of a higher quality.
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.
World production of pigeon peas is estimated at 4.49 million tons.About 63% of this production comes from India.The total number of hectares grown to pigeon pea is estimated at 5.4 million.Indiaaccounts for 72% of the area grown to pigeon pea or 3.9 million hectares.Africais the secondary centre of diversity and at present it contributes about 21% of global production with 1.05 million tons.Malawi,Tanzania,Kenya,MozambiqueandUgandaare the major producers in Africa.
The pigeon pea is an importantlegumecrop ofrainfed agriculturein thesemiarid tropics. The Indian subcontinent, Africa andCentral America, 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 withcereals, such assorghum(Sorghum bicolor),pearl millet(Pennisetum glaucum), ormaize(Zea mays), or with other legumes, such aspeanuts(Arachis hypogea). Being a legume capable ofsymbiosiswithRhizobia, the bacteria associated with the pigeon pea enrich soils through symbioticnitrogen fixation.
The crop is cultivated on marginal land by resource-poor farmers, who commonly grow traditional medium- and long-duration (5–11 months)landraces. 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 or 620 lb/acre). 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 and can be grown in areas with less than 650 mm annual rainfall. With the maize crop failing three out of five years in drought-prone areas ofKenya, a consortium led by theInternational Crops Research Institute for the Semi-Arid Tropics(ICRISAT) aimed to promote the pigeon pea as a drought-resistant, nutritious alternative crop.
Legumes, which provide highly nutritious products and contribute to soil fertility through biologicalnitrogen fixation, are one of the most important crops in mixed crop-livestock systems.Cajanus cajanis an important legume crop with a high N-fixation ability (79 % N derived from the atmosphere).Plant-growth promoting rhizobacteria (PGPR), together with strains ofRhizobium, can enhance growth and nitrogen fixation in pigeon pea by colonizing thenselves in the plantnodules.Thesebioinoculantscan be added as a single species but also as combined communities. Using a single bioinoculant shows benefits, but mixed communitites of different bioinoculatns have a greater positive impact on nodulation, plant dry mass, as well as shoot and root length.These different community species have different functions for the pigeon pea:
Pigeon pea is affected by a variety of pests and insects that can significantly impact crop yield and quality. They can infest the plant from seedling stage till harvest, therefore pests and diseas are the primary cause for low yields.The major pests are moths include the gram pod borer (Helicoverpa armigera), which causes defoliation and pod damage; the blue butterfly (Lampides boeticus), which infests buds, flowers, and young pods; and the spotted pod borer (Maruca vitrata), known for webbing together infested pods and flowers.The tur pod bug (Clavigralla gibbosa) is another significant pest of pigeon pea, causing substantial damage to pods and seeds.Current resistance efforts focus on breeding pigeon pea varieties with enhanced resistance to these pests. However, the presence of multiple pest species and the variability in pest pressure across regions pose challenges to achieving consistent resistance.Effective management techniques includeintegrated pest management(IPM) strategies such ascrop rotation,intercroppingwith non-host plants, timely sowing, and the use of biological control agents likeparasitoidsandpredators.Chemical control measures, including the application of insecticides like neem-based products and syntheticpyrethroids, are also employed when necessary.
Common Diseases of Pigeon Pea:
Pigeonpea is unique among legumes in that its flowers support both cross-pollination andself-pollination. The bright, nectar-rich flowers attract pollinating insects, allowing naturaloutcrossing, which averages about 20% but varies with location due to pollinator populations. This level of outcrossing can lead togenetic contaminationof parental lines and complicate the selection of lines by reducing the homozygosity of progeny. To mitigate these effects, breeders use techniques such as enclosing flowers inmuslinbags or nets to prevent insect pollination. However, natural outcrossing also results in genetically diverse landraces and requires two to three generations of selfing before parental lines can be used in hybridisation programmes.
Over 50 years of pigeonpea breeding has resulted in genetic improvements, disease-resistant varieties, a reduction in crop maturity from 300 to less than 90 days, and the introduction of the first legume hybrid technology, which has increased yields by 30-50%. Despite these advances, yield per unit area has remained stable, with improved stability and diversification for farmers.
John Spence, abotanistand politician fromTrinidad and Tobago, developed several varieties of dwarf pigeon peas which can be harvested by machine, instead of by hand.
The pigeon pea is the first seed legume plant to have its complete genome sequenced. The sequencing was first accomplished by a group of 31 Indian scientists from theIndian Council of Agricultural Research. It was then followed by a global research partnership, the International Initiative for Pigeon pea Genomics (IIPG), led byICRISATwith partners such as BGI–Shenzhen (China), US research laboratories like University of Georgia, University of California-Davis, Cold Spring Harbor Laboratory, and National Centre for Genome Resources, European research institutes like the National University of Ireland Galway. It also received support from the CGIAR Generation Challenge Program, US National Science Foundation and in-kind contribution from the collaborating research institutes.It is the first time that a CGIAR-supported research center such as ICRISAT led the genome sequencing of a food crop. There was a controversy over this as CGIAR did not partner with a national team of scientists and broke away from the Indo American Knowledge Initiative to start their own sequencing in parallel.
The 616 maturemicroRNAsand 3919long non-codingRNAssequences were identified in the genome of pigeon pea.
Various methodologies exist in order to remove the pulse from its shell. In earlier days hand pounding was common. Several traditional methods are used that can be broadly classified under two categories: the wet method and the dry method. The Wet method Involves water soaking, sun drying and dehulling. The Dry method Involves oil/water application, drying in the sun, and dehulling. Depending on the magnitude of operation, large-scale commercial dehulling of large quantities of pigeon pea into its deskinned, split version, known as toordalin Hindi, is done in mechanically operated mills.
Pigeon peas are both a food crop (dried peas, flour, or green vegetable peas) and a forage/cover crop. In combination withcereals, pigeon peas make a well-balanced meal and hence are favored by nutritionists as an essential ingredient for balanced diets. 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 Cape Verde they make a soup with the dried pigeon peas called feijão Congo, after its own name, made with dried pigeon peas in a similar manner to Brazilianfeijoada.
In Kenya and throughout the Swahili-speaking region of East Africa, pigeon peas are utilized in dishes such asmbaazi namahamri, that is usually served for breakfast.
In theEnugu stateof Nigeria, and igbo dish calledẸchịchaorAchịchais made withpalm oil, cocoyam, and seasoning.It is also similar to other dishes from the state such asayarya jiandfio-fio.
InEthiopia, the pods, the young shoots and leaves, are cooked and eaten.
In India, it is one of the most popularpulses, being an important source of protein in a mostly vegetarian diet. It is the primary accompaniment to rice orrotiand has the status ofstaple foodthroughout the length and breadth of India. In regions where it grows, fresh young pods are eaten as a vegetable in dishes such assambar.
In theWestern Visayasregion of thePhilippines, pigeon peas are the main ingredient of a very popular dish called "KBL" - an acronym for "Kadyos" (pigeon pea), "Baboy" (pork), and "Langka" (jackfruit). It is a savory soup with rich flavors coming from the pigeon peas, smoked pork preferably the legs or tail, and souring agent calledbatuan. Rawjackfruitmeat is chopped and boiled to soft consistency, and serves as an extender. The violet color of the soup comes from the pigment of the variety commonly grown in the region.
In the Caribbean coast ofColombia, such as theAtlántico departmentof Colombia, thesopa de guandú con carne salada(or simply "gandules") is made with pigeon peas, yam, plantain, yuca, and spices.During the week ofSemana santaa sweet is made out of pigeon peas calleddulce de guanduleswhich is made by mashed and sweetened pigeon peas with origins in themarooncommunity ofSan Basilio de Palenque.
In theDominican Republic, a dish made of rice and green pigeon peas calledmoro de guandulesis a traditional holiday food. It is also consumed as guandules guisados, which is a savoury stew with coconut and squash served with white rice. A variety ofsancochois also made based on green pigeon peas that includes poultry, pork, beef, yams, yucca, squash, plantain and others.Dominicanshave a high regard for this legume and it is consumed widely.
InPanama, pigeon peas are used in a dish calledArroz con guandú y cocoor "rice with pigeon peas and coconut" traditionally prepared and consumed during the end of year holidays.
InPuerto Rico,arroz con gandulesis made withriceand pigeon peas andsofritowhich is a traditional dish, especially during Christmas season.Pigeon peas can also be made in to a stew calledasopao de gandules, withplantainballs.Escabechede gandulesis a spicy pickled pigon pea salad typically served with bread. Pigeon peas are also used to makehummuson the island and calledhummus de gandules.
Jamaicaalso uses pigeon peas instead of kidney beans in theirrice and peasdish, especially during the Christmas season.
Trinidad and TobagoandGrenadahave their own variant, calledpelau, which includes either beef or chicken, and occasionally pumpkin and pieces of cured pig tail.
Unlike in some other parts of the Greater Caribbean, inThe Bahamaspigeon peas are used in dried form, light brown in color to make the heartier, heavier, signature Bahamian staple dish "Peas 'n Rice."
InHawaiithey are used to make a dish calledgandule rice,also calledgodule rice,gundule rice,andganduddy riceoriginates on the island from thePuerto Ricancommunity with historic ties to the island and is prepared in a similar manner to that of traditional Puerto Rican arroz con gandules.
It is an important ingredient of animal feed used in West Africa, especially in Nigeria, where it is also grown. Leaves, pods, seeds and the residues of seed processing are used to feed all kinds of livestock.
In theCongopigeon peas are utilized as one of the mainfood forestand soil improvement crops after using aslash-and-burn firetechnique calledmaala.
Pigeon peas are in some areas an important crop forgreen manure, providing up to 90 kg nitrogen per hectare.The woody stems of pigeon peas can also be used as firewood, fencing, thatch and as a source for rope fiber.
Pigeon pea has been valued for its medicinal properties since prehistoric times in various regions, including Africa, Egypt and Asia. Today, different countries use different parts of the plant to treat a range of diseases as an alternative medicine. In theRepublic of CongotheKongo,Lari, andDondo peopleuse the sap of the leaves as an eyedrop for epilepsy.In Nigeria the leaves are used to treat malaria, while in India they are used to treat diabetes, stomach tumours and wounds. In Oman, pigeon pea is used to treat chronic diseases, and in traditional Chinese medicine it is used to relieve pain and control intestinal worms. In Africa, the seeds are used to treat hepatitis and measles. The widespread traditional medicinal use of the plant is attributed to its rich content of phenolic compounds, which have antiviral, anti-inflammatory, antioxidant, hypocholesterolemic and hypoglycaemic effects. The leaves also contain flavonoids, terpenoids, essential oils and coumarin, which further enhance its therapeutic potential in the fight against disease.There are different studies looking at how the medicinal compounds of pigeon pea could be used in future. One study, using rats, found that a pigeonpea beverage could be used as an anti-diabetic functional drink. This drink would help to reduce plasma glucose and total cholesterol levels and increase plasma antioxidant status. Therefore, it could be used in future as an alternative strategy to maintain plasma glucose and cholesterol at normal levels and help prevent diabetes complications.Furthermore, pigeon pea could be used as a fermented food as this would increase its antioxidant levels and therefore, have an antiatherosclerotic effect. This would help to improve systolic blood pressure as well as diastolic blood pressure. This benefits  cardiovascular health and could be developed as a new dietary supplement or functional food that prevents hypertension.
In Madagascar the branches have been used as ateeth cleaning twig.