Prota 1: Cereals and pulses/Céréales et légumes secs
Sp. pl. 2: 727 (1753).
Papilionaceae (Leguminosae - Papilionoideae, Fabaceae)
2n = 14
– Field pea, pea (En). Pois, pois sec (Fr). Ervilha (Po). Njengere, njegere (Sw).
– Garden pea, pea, petit-pois (En). Petit pois (Fr). Ervilha (Po). Njengere, njegere (Sw).
– Sugar pea, pea pod, snap pea, snow pea, mange-tout (En). Pois mangetout, pois gourmand (Fr). Ervilha torta (Po).
Origin and geographic distribution
The origin and progenitors of Pisum sativum are not well known. The Mediterranean region, western and central Asia, and Ethiopia have been indicated as centres of origin. Recently FAO designated Ethiopia and western Asia as centres of diversity, with secondary centres in southern Asia and the Mediterranean region. Archaeological evidence of the use of pea dating from 8000 BC has been found in the Fertile Crescent. The first cultivation of pea appears to have been in western Asia, from where it spread to Europe, China and India. In classical times Greek and Roman authors mentioned its cultivation as a pulse and fodder crop. Pea was already well known in the mountain regions of Central and East Africa before the arrival of the Europeans and was a well-established and important food crop in Rwanda and south-western Uganda by 1860. The use of the edible pods was first described in the Netherlands and France during the 16th century, whereas the use of immature seeds as a vegetable began in Europe a century later.
At present, Pisum sativum is found in all temperate countries and in most tropical highlands. Field pea is extensively grown in the highlands of eastern Central Africa and East Africa (notably Ethiopia), and in southern Africa. In parts of Rwanda and Uganda it is the main pulse crop. Field pea is hardly grown in West Africa. In Africa garden pea and sugar pea are mostly considered exotic products. They are regionally of some importance, sugar pea more in Francophone countries, garden pea more in Anglophone countries. Imported canned garden pea seeds are available everywhere in food shops.
Three main types of pea cultivars can be distinguished: field pea, grown for the dry seeds; garden pea, grown for the immature green seeds; and sugar pea, grown for the immature pods. The dry seeds of field pea are first soaked in water to soften and are then boiled and consumed as a pulse dish. Alternatively, they are decorticated and split (‘split peas’) before boiling. They are also consumed roasted. The young pods of sugar pea are boiled for a few minutes only, to preserve their crispness; after boiling they may be stir-fried before consumption. The young seeds of garden pea are also boiled for a few minutes. They are commonly offered as canned or – in Western countries – as deep frozen products. In Ethiopia the annual consumption per person of pea seeds is estimated at 6–7 kg. Main dishes include ‘shiro wot’ (split pea seeds ground and made into stew) and ‘kik wot’ (split pea seeds boiled and made into stew). Snacks include ‘eshet’ (fresh green field pea seeds either eaten raw or roasted), ‘nifro’ (boiled dry or fresh green pea seeds) and ‘endushdush’ (seeds soaked first and then roasted). In local markets white- and cream-coloured seeds are preferred for ‘kik’-making, and grey-coloured seeds for ‘shiro’-making. In Malawi and some Asian countries, the young shoots are used as a leafy vegetable. In Western countries dry, mature pea seeds are extensively used as animal feed. The haulms or straw after threshing are used as forage, hay, silage and green manure. Apart from being an important source of food and feed, pea plays a role in soil fertility restoration as a suitable rotation crop that fixes atmospheric nitrogen.
The seeds of pea are claimed to have beneficial effects on many types of skin complaints; face masks made from crushed seeds are used to treat acne and wrinkled skins.
Production and international trade
FAO estimated the annual world dry pea seed production in 1999–2003 at about 10.5 million t from 6.2 million ha. The main producers are Canada (2.1 million t/year from 1.1 million ha), France (1.9 million t/year from 400,000 ha), China (1.1 million t/year from 900,000 ha) and the Russian Federation (1.1 million t/year from 700,000 ha). The annual production in tropical Africa for this period was about 310,000 t from 470,000 ha. Here, the main producers are Ethiopia (135,000 t/year from 184,000 ha), DR Congo (65,000 t/year from 96,000 ha), Burundi (32,000 t/year from 49,000 ha), Tanzania (28,000 t/year from 63,000 ha), Uganda (18,000 t/year from 29,000 ha) and Rwanda (14,000 t/year from 30,000 ha). The annual world production of green pea seeds in 1999–2003 was about 8.7 million t from 1.0 million ha, the main producers being India (3.4 million t/year from 300,000 ha), China (1.5 million t/year from 190,000 ha) and the United States (1.0 million t/year from 96,000 ha). In tropical Africa about 30,000 t green pea seed was produced annually from 6400 ha, mainly in Kenya (23,000 t/year from 5600 ha).
Statistics on the international trade in pea seed are generally scanty, as they are mostly aggregated in ‘pulse crops’ as a whole. The main exporting countries are Canada, Australia, France and China. Canada focuses on the European stock feed market and in recent years on the food market in India. Australia focuses on the food markets and the domestic feed market. The top importers for pea feed or food are Spain, Bangladesh, Belgium, India, China, United States, Colombia, United Arab Emirates and Malaysia. Almost all the production in Ethiopia is consumed locally. Most sugar pea pods produced in the world are sold in local markets. Western countries import large quantities of sugar pea pods from developing tropical countries because locally produced ones are available for only a short time of the year and because of the high labour costs of picking. Kenya exports yearly 4500 t sugar pea pods to the European Union. Garden pea seeds are mostly exported as canned or frozen products from Western countries, e.g. the United States and France, but statistical data are not available.
Whole mature dried seeds of field pea contain per 100 g edible portion: water 13.3 g, energy 1269 kJ (303 kcal), protein 21.6 g, fat 2.4 g, carbohydrate 52.0 g (starch 47.6 g), fibre 15.0 g, Ca 61 mg, Mg 120 mg, P 300 mg, Fe 4.7 mg, Zn 3.7 mg, carotene 245 μg, thiamin 0.6 mg, riboflavin 0.3 mg, niacin 3.0 mg, vitamin B6 0.13 mg, ascorbic acid trace (Holland, Unwin & Buss, 1991). The content of essential amino acids per 100 g food is: tryptophan 210 mg, lysine 1620 mg, methionine 210 mg, phenylalanine 1000 mg, threonine 860 mg, valine 1000 mg, leucine 1480 mg and isoleucine 930 mg (Paul, Southgate & Russell, 1980). The composition of wrinkled pea seeds is different from rounded ones; they have less starch ( 27–37 g) and more fat (5 g) and sugars. Antinutritional factors in pea seeds include trypsin inhibitors, haemagglutinins (lectins), tannins, oligosaccharides and phytate. Cultivars with a darker seed coat contain more tannin, which tends to decrease their digestibility.
Raw garden pea seeds, immature taken from the pods (refuse 63%) contain per 100 g edible portion: water 74.6 g, energy 348 kJ (83 kcal), protein 6.9 g, fat 1.5 g, carbohydrate 11.3 g (starch 7.0 g), fibre 4.7 g, Ca 21 mg, Mg 34 mg, P 130 mg, Fe 2.8 mg, Zn 1.1 mg, carotene 300 μg, thiamin 0.75 mg, riboflavin 0.02 mg, niacin 2.5 mg, folate 62 μg, ascorbic acid 24 mg.
Raw sugar pea pods, with the ends trimmed (refuse 8%) contain per 100 g edible portion: water 88.7 g, energy 134 kJ (32 kcal), protein 3.6 g, fat 0.2 g, carbohydrate 4.2 g (starch 0.8 g), fibre 4.2 g, Ca 44 mg, Mg 28 mg, P 62 mg, Fe 0.8 mg, Zn 0.5 mg, carotene 695 μg, thiamin 0.2 mg, riboflavin 0.15 mg, niacin 0.6 mg, folate 10 μg, ascorbic acid 54 mg (Holland, Unwin & Buss, 1991).
Annual, climbing, glabrous herb up to 2(–3) m tall (up to 1.3 m for sugar pea types); taproot well developed, up to 1.2 m long, with many lateral roots; stem terete, with no or few basal branches, internodes hollow. Leaves alternate, pinnate, with 1–3(–4) pairs of leaflets and ending in a usually branched tendril; stipules leaf-like, up to 8(–10) cm × 4 cm; petiole (2–)4–6 (–7.5) cm long; leaflets shortly stalked, ovate to elliptical, 1.5–8 cm × 0.5–4 cm, entire to toothed, sometimes converted into tendrils. Inflorescence an axillary, 1–3-flowered raceme. Flowers bisexual, papilionaceous; calyx with tube 4–8 mm long, lobes as long or longer than tube; corolla white to purple, standard 1–3 cm × 2.5–4.5 cm, wings a little shorter than standard, keel much shorter; stamens 10, 9 united and 1 free; ovary superior, 1-celled, style curved, longitudinally grooved. Fruit an oblong-ovate pod 3.5–15 cm × 1–2.5 cm, pendant, 2–11-seeded. Seeds globose, sometimes wrinkled, 5–8 mm in diameter, varying in colour from uniform yellow (sugar pea), green (crinkled garden pea) to purple or spotted or cream-white, sometimes with black hilum. Seedling with hypogeal germination; cotyledons remaining within testa; first 2 leaves simple.
Other botanical information
Pisum comprises a few species and is related to Lathyrus, Lens and Vicia, from which it can be distinguished by its terete stems, very large stipules and longitudinally grooved style.
Pisum sativum has long been studied by geneticists; Knight did his crossing experiments on it in 1787, and it was the subject of the pioneering work of Gregor Mendel in the 19th century. Within Pisum sativum several varieties or subspecies have been distinguished. A classification in cultivar groups is more appropriate. Sativum Group is cultivated worldwide, including tropical Africa. Abyssinicum Group (Abyssinian pea) is cultivated in the northern (Tigray and Wollo) and south-eastern (Arsi) parts of Ethiopia; it is also grown in Yemen. The latter differs in having leaves with only one pair of leaflets (Sativum Group: 2–3 pairs), and smaller, red-purple flowers. It has slightly glossy seeds with a black hilum; these may mature earlier. Other cultivar groups, varieties or subspecies occur outside Africa; 2 of these represent wild populations from southern Europe and western Asia.
Purple coloured flowers are associated with bitter tasting green seeds. For this reason nearly all garden pea cultivars are white-flowered, while most field pea cultivars are purple-flowered and sugar pea cultivars can have white or purple flowers.
Growth and development
Pea seeds germinate at ambient temperatures of between 4–24°C, with 13–18°C being optimal. In sugar pea cultivars flowers appear between the 6th and 12th nodes according to cultivar earliness, normally 5–7 weeks after emergence. At optimum temperatures, pods are ready for harvesting 12 days later. For garden pea the duration of the flowering period is 2–3 weeks in cultivars for mechanical harvesting, up to one month in garden cultivars. For field peas the period from emergence to dry seed harvest ranges from 3–6 months depending on cultivar and environment. Most field pea cultivars grown in Africa have an indeterminate growth habit. In a 2-season experiment with 63 genotypes in Ethiopia at 3000 m altitude, the period to flowering and maturity ranged from 80–104 days and 149–163 days, respectively. Pea flowers are self-pollinated, with usually less than 1% outcrossing. Pea is nodulated by Rhizobium leguminosarum.
Pea requires a relatively cool climate, with average temperatures between 7–24°C, and with optimum yields at average temperatures of 13–21°C, although maximum rates of development and vegetative growth are reached at considerably higher temperatures. It can be grown at elevations above 1000 m near the equator, or at lower elevations (even in coastal areas) during the cool season at latitudes between 15–20°. Young plants can withstand frost if progressively hardened by lowering temperatures. Pisum sativum is grown in areas with an annual rainfall as low as 400 mm, but the optimum is 800–1000 mm/year. It is slightly susceptible to daylength, with long days promoting flowering. In most tropical circumstances it can be considered day-neutral. In Ethiopia rainfed field pea is grown at 1800–3000 m altitude, because it suffers from diseases and drought at lower altitudes and from frost at higher altitudes. It is mostly grown in the main rainy season (June–December). In Uganda pea plants grow best at altitudes above 1800 m, and in Kenya optimum yields are obtained at 2100–2700 m altitude. Pea grows on a wide range of soil types with moderate fertility levels, well drained and with pH 5.5–7.0, although some cultivars tolerate a pH up to 7.5. It is seriously affected by soil acidity, aluminium toxicity and waterlogging.
Propagation and planting
Pea is propagated by seed. The 1000-seed weight ranges from 100 g to 500 g. Sugar pea is sown in double rows 10 cm apart with 60 cm (30–80 cm) between the double rows. Within the rows the seed of small cultivars is sown 3–5 cm apart, for taller cultivars up to 10 cm apart. Garden pea is sown rather densely, with plant densities up to 80 plants per m2. The seed should be sown 4–7 cm deep. Per ha 60–200 kg of seed is required, with the highest rates for garden pea. Field pea is mostly broadcast in Africa. Even though it does not require a fine seedbed, 2–3 ploughings with animal-drawn ploughs or one disc ploughing followed by two disc harrowings may be beneficial. Timely sowing is essential for optimum yields, since late-sown crops are often affected by low moisture availability and heavy aphid infestation at medium altitudes and by frost at high altitudes. In Ethiopia field pea is produced either as a sole crop or in mixed cropping with other crops, e.g. faba bean (Vicia faba L.). In the latter case, faba bean provides physical support and good aeration to field pea, whereas field pea suppresses weed growth. In Ethiopia mixed cropping of field pea with faba bean significantly slows down the rate of Ascochyta blight development and results in higher yields than pure stands. In the Kilimanjaro region of Tanzania pea is grown during the cool season in association with crops such as coffee, banana, tomato and maize. The same practice is found in parts of Kigezi District of Uganda. In Malawi (Ntheu District) it is also grown during the cool season, mostly as a garden crop in mixed stands with other crops, notably wheat. In the tropics, e.g. Rwanda and south-western Uganda, field pea is often the first crop after a fallow period. In temperate areas sugar pea is sown either in autumn or in early spring.
Sugar pea plants are normally supported. The stems are not twining, but grasp the support with their tendrils. They do not need vertical poles, but the poles can be crossed, or the plants are supported by wire mesh, horizontal wires, vertical lattices or nets, depending on the potential height of the cultivar grown. Garden pea is seldom supported, field pea not at all. Weeds should be rigorously controlled. The critical period of weed competition is 3–8 weeks after emergence. Both annual and perennial grasses affect field pea. Weeds can be controlled by hand weeding where labour is cheap, whereas chemical weed control is more practical in large-scale production. Early land preparation can encourage weed seeds to germinate so that they can be destroyed in subsequent cultivation.
Field pea normally needs no fertilizer N as the amount present in the soil and fixed by the plant is sufficient. The total uptake of a crop yielding 5–6 t of seed per ha is 30–35 kg/ha P and 200–250 kg/ha K. Young sugar pea and garden pea respond well to a starter dose of N fertilizer, even when nodulation occurs. An indicative fertilizer recommendation on light medium-rich alkaline soils is 40 kg N, 50 kg P, 150 kg K and 30 kg Mg per ha. Irrigation is necessary in dry conditions, e.g. 10 mm twice a week.
Diseases and pests
Ascochyta blight is a disease complex caused by Ascochyta pisi , Mycosphaerella pinodes (Ascochyta pinodes), and Phoma medicaginis (Ascochyta pinodella); it is widespread throughout the world. It is favoured by frequent rains and high humidity. Moderate levels of resistance have been detected in landraces and in the related Pisum fulvum Sibth. & Sm., which occurs wild in western Asia. Powdery mildew caused by Erysiphe pisi is widespread and important wherever pea is grown. Resistant cultivars have been developed. In sugar pea a recessive resistance gene is present in the cultivar ‘Manoa Sugar’ bred in Hawaii. Bacterial blight (Pseudomonas syringae pv. pisi) is common where pea is grown intensively and humidity is high. Downy mildew (Peronospora viciae) may develop at high altitudes where temperatures are between 1°C and 18°C. As Ascochyta blight, powdery mildew, bacterial blight and downy mildew are seedborne, the use of certified disease-free seed is essential. If own seed is to be used, it may be treated with a systemic fungicide to control Ascochyta blight and powdery mildew. In addition, wide row spacing, eradication of weeds, surface irrigation and rotations of three years or longer help to manage bacterial blight and other diseases. Aphanomyces root rot (Aphanomyces euteiches) is a major root pathogen of pea worldwide. It is extremely difficult to control, as no effective fungicides are available. The development of resistance/tolerance to this disease will be necessary for effective control. Another important soil-borne disease is Fusarium wilt caused by Fusarium oxysporum f.sp. pisi, but cultivars resistant to this disease are available. Aphid-transmitted virus diseases include bean yellow mosaic virus (BYMV), pea seedborne mosaic virus (PSbMV), pea leaf-roll (BLRV - bean leaf-roll luteovirus) and pea enation mosaic virus (PEMV). Recent sugar pea cultivars bred in southern France are relatively tolerant to severe infestation by these viruses (e.g. ‘Supermangetout’ compared to the traditional ‘Carouby de Maussane’). The pea cyst nematode (Heterodera goettingiana) can cause considerable crop loss; control measures are crop rotation and the use of chemicals.
Insect pests attacking pea include cutworms (Agrotis spp.), aphids (including the pea aphid Acyrthosiphon pisum, a vector of many virus diseases, which has become a major pest in Ethiopia and Uganda), bollworms (Heliothis armigera and Spodoptera exigua) and the pea weevil (Bruchus pisorum). Bruchids (Callosobruchus spp.) are a major storage pest of field pea, e.g. in Ethiopia.
The parasitic weed Orobanche crenata Forssk. causes crop losses in pea in the Mediterranean region.
To control insect pests and diseases, integrated pest management (IPM) is recommended: use of resistant/tolerant cultivars; use of certified disease-free seed or seed treatment of own seed; keeping fields weed-free; appropriate fertilizing and irrigation; growing pea for seed in semi-arid and/or arid areas; regular monitoring of the crop; and judicious use of biocides.
Sugar pea pods and garden pea seeds are ready for harvesting 8–12 weeks from sowing, field pea seeds one month later. Pods of sugar pea are hand-picked every second day during a 15–20 day period. Garden pea seeds are either handpicked or – in large scale production for canning – machine-harvested. Late harvesting of field pea may result in shedding and rotting of pods and shattering of the seeds. Therefore, harvesting should be done at the appropriate stage: when the leaves begin to yellow, the lower pods begin to wrinkle, and the seed moisture content is reduced to 16–18%. In most parts of Africa where the time of harvest more or less coincides with the start of the dry season, it is easy to achieve low moisture contents while the crop is still in the field. Most field pea cultivars have an indeterminate growth habit and the pods do not mature simultaneously. Therefore, the harvested plants should be dried before threshing. In most parts of Africa (e.g. Ethiopia), harvesting of field pea is done with sickles, the crop is transported to threshing ground and stacked for a few days to dry in the sun. The stack is then spread on the ground and threshed usually by beating with sticks or by trampling with animals.
Yields of field pea range from less than 1 t/ha in Africa and South America to over 4 t/ha in Europe. The average world yield is around 1.7 t/ha. Under good growing conditions sugar pea yields of up to 8 t/ha edible pods per ha can be obtained. Garden pea may produce 4–7 t/ha young seeds.
Handling after harvest
The initial seed moisture content of field pea must be reduced to the required level of about 12% before storage. Optimum moisture content reduces the deterioration rate during storage and prevents or reduces attack by moulds and insects. The seed should be stored in a dry and cool place, free of pests and protected from absorbing moisture from the surroundings. In tropical Africa, e.g. in Ethiopia, pea seed is not stored for more than one season because of insect damage, particularly by bruchids. Small-scale farmers do not commonly use insecticides. Bins made of earth (smeared with cow dung) or wooden materials (sealed with mud) are the most commonly used storage structures in tropical Africa. Sugar pea pods can be kept for only 2–3 days at temperatures of 20–25°C, but for more than 15 days at 2.5–5°C in perforated plastic bags or crates covered with perforated plastic sheets. Garden pea seeds may be kept for 1–3 weeks at temperatures of 0–4°C and a relative humidity of 88–92%.
A large genetic diversity has been found in Pisum sativum collections from both Africa (e.g. Ethiopia) and Asia (e.g. India). Genetic erosion in field pea is probably less than in cereals, because of less progress in cultivar development and hence less replacement of landraces by a few new cultivars. Many germplasm collections of pea are held all over the world. The world collection of cultivars and mutant forms of Pisum sativum is housed at the Nordic Gene Bank, Alnarp, Sweden (about 2700 accessions). Emphasis in the collection is on lines with multiple disease resistance, wild and primitive types, lines carrying structural mutations, breeding lines and cultivars of special interest. Large Pisum sativum collections are held in Australia (Australian Temperate Field Crops Collection, Horsham, Victoria, 6300 accessions), the Russian Federation (N.I. Vavilov All-Russian Scientific Research Institute of Plant Industry, St. Petersburg, 6200 accessions), Italy (CNR - Istituto di Genetica Vegetale, Bari, 4100 accessions), the United States (Western Regional Plant Introduction Station, Pullman, 3500 accessions; Horticultural Sciences Department, NY State Agricultural Experiment Station, Geneva, 2500 accessions), China (Institute of Crop Germplasm Resources (CAAS), Beijing, 3400 accessions), and the United Kingdom (John Innes Centre, Department of Applied Genetics, Norwich, 2700 accessions). The largest collection of Pisum sativum germplasm in Africa is located at the Institute of Biodiversity Conservation, Addis Ababa, Ethiopia, with over 1600 accessions.
All commercial cultivars of Pisum sativum are pure lines. The main breeding objectives in temperate regions are colour and quality for fresh product markets and canning, mechanization and cold tolerance. Breeding in most parts of the tropics has an improved seed yield as a first priority through the development of productive cultivars tolerant/resistant to different stress factors and suitable for different agro-ecological conditions. Some progress has been made. In addition to improved yield potential, sources of resistance to powdery mildew have been identified. Attempts to transfer resistance to Ascochyta blight from a wild type have not been successful because of complications due to polygenic inheritance and linkage with other traits. The presence of physiological races of the pathogens is another problem. Manipulation of morphological traits has resulted in determinate types with even maturity, suitable for mechanization and semi-leafless types with reduced lodging. A peculiar mutant character, ‘Afila’, with tendrils in the place of leaflets has been introduced in commercial dwarf field pea cultivars. Breeding efforts during the past three decades in Africa have resulted in the release of a number of cultivars (obtained by introduction, hybridization and local selection), but most farmers still use their own farm-saved seed of local cultivars; well-known cultivars are ‘Mitali’ and ‘Miseriseri’. In Ethiopia more than 15 cultivars, with superior yield potential, seed size, seed colour and disease resistance, have been released for different agro-ecological conditions. These cultivars include ‘Holetta’ (from local collection), ‘Tegegnech’ (introduced from Burundi), ‘Hassabe’ and ‘Markos’ (introduced from the International Center for Agricultural Research in the Dry Areas, ICARDA) and ‘Adi’, ‘Milky’ and ‘Wolmera’ (obtained by hybridization of adapted local cultivars with introductions from the United States and ICARDA).
For sugar pea breeding the most urgent objective is powdery mildew resistance (available in ‘Manoa Sugar’) and to a lesser extent Ascochyta resistance (from green pea cultivars). The ‘edible pod’ character (absence of ‘parchment’ in the pod walls) is induced by two recessive genes. A mutation inducing thickening of this wall of up to 3 mm was recently introduced in American cultivars, giving rise to the ‘sugar snap pea’. The ‘sugar snap’ character will be interesting if it appears attractive to consumers. It might also be interesting to introduce more new characters into sugar pea, e.g. true dwarfs which could be grown without support, or climbing semi-leafless types in order to increase yields by higher plant densities and to make fruit picking easier. Well-known cultivars of sugar pea in Africa are ‘Sugar Snap’, ‘Carouby de Maussane’, ‘Oregon Sugar Pod’, ‘Shield’ and ‘Sugar Queen’. Some cultivars of garden pea are ‘Alderman’, ‘Télévision’ and ‘Green Feast’. Many growers use their own seed originating from old introductions.
A consensus genetic linkage map has been developed for Pisum sativum based on various linkage maps. Quantitative trait loci associated with, among others, seed yield, seed protein concentration, early maturity, lodging resistance, plant height and resistance to various biotic stresses (including Ascochyta blight, Aphanomyces root rot and Orobanche crenata) have been identified. Procedures for direct as well as indirect, callus-mediated somatic embryogenesis of pea have been developed for breeding purposes. Transgenic plants have been produced using Agrobacterium -based transformation vectors, e.g. to increase resistance to Callosobruchus chinensis, Callosobruchus maculatus and Bruchus pisorum by incorporating α -amylase-inhibiting capacity from Phaseolus vulgaris.
Field pea will remain important in Central and East Africa, as well as in temperate areas. It is a major and cheap source of protein, fixes atmospheric nitrogen, and plays an important role in farming systems by breaking cereal monoculture. A drawback is its susceptibility to diseases, which can best be counteracted by the development of resistant cultivars. As a potential export crop, it might represent a special opportunity in the years to come and the major pea-producing countries of tropical Africa could benefit from African (Morocco and Sudan), European (Netherlands, France and Greece), Middle Eastern (Israel and Yemen) and Asian (India and Pakistan) markets. Sugar pea and garden pea will become gradually more important in city markets in tropical Africa. Sugar pea is often considered a tastier vegetable than French bean and it could be interesting to develop its production for the domestic African market and for export. Garden pea could be produced locally on a larger scale to replace imports in canned form.
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Correct citation of this article:
Messiaen, C.-M., Seif, A.A., Jarso, M. & Keneni, G., 2006. Pisum sativum L. In: Brink, M. & Belay, G. (Editors). PROTA 1: Cereals and pulses/Céréales et légumes secs. [CD-Rom]. PROTA, Wageningen, Netherlands.
1, shoot with flower; 2, part of shoot with fruit; 3, seed.
detail of flowering plant
close up of flower
flowering and fruiting crop