Indigenous vegetables of Sudan: production, utilization and conservation

Mirghani K. Ahmed and El Tahir I. Mohammed
Agricultural Research Corporation, Wad Medani, Sudan

Introduction

Consumption and use of vegetable crops was once very limited in Sudan. People used to rely on subsistence staples such as sorghum and wild vegetables such as Abelmoschus and Corchorus (Table 1). Introduction of exotic species and varieties of vegetables started very early this century, mainly from Egypt (Badry 1984). A number of vegetable crops are now important in the country (Table 2). Preliminary evaluation and observations have shown that there is great variability within many of these crops, which is considered a highly valuable resource for genetic improvement programmes.

Table 1. Wild plants used as vegetables in Sudan.

Scientific name	Family	Parts of plant used
Abelmoschus spp.	Malvaceae	Fruits, leaves
Amaranthus graecizans	Amaranthaceae	Leaves
Amaranthus sp.	Amaranthaceae	Leaves
Cleome gynandra	Capparidaceae	Leaves
Corchorus fasciculararis	Tiliaceae	Leaves
Corchorus olitorius	Tiliaceae	Leaves
Cucumis melo var. agrestis	Cucurbitacaeae	Fruits
Portulaca oleracea	Portulacaceae	Leaves, stems
Sonchus carnutus	Astercaceae	Leaves (green salad)
Sonchus oleraceus	Asteraceae	Leaves

Table 2. Indigenous vegetables cultivated in the Sudan.

Scientific name	Family	Parts of plant used
Abelmoschus esculentus	Malvaceae	Fruit
Allium cepa	Anarylidaeae	Bulbs
Capsicum frutescens	Solanaceae	Fruit
Citrullus vulgaris	Cucurbitaceae	Fruit
Corchorus olitorius	Tiliaceae	Leaves
Cucumis melo	Cucurbitaceae	Fruit
Cucumis melo var. agrestis	Cucurbitaceae	Fruit
Cucumis sativus var. flexusus	Cucurbitaceae	Fruit
Cucurbita maxima	Cucurbitaceae	Fruit
Eruca sativa	Crufiferaea	Leaves
Portulaca oleracea	Portulacaceae	Leaves, stems
Vigna unguiculata	Leguminosae	Leaves

Production

Vegetables are usually produced by small farmers in rain-fed areas, irrigated private farms or the big government schemes. Compared with cash crops like cotton and with the staple food grains, little attention has been paid so far to vegetable production. Therefore, reliable data on the area and production of vegetables are difficult to obtain. With respect to regional distribution, the Central State is by far the most important production area, followed by the Northern State. Production in the remote areas of Western and Southern Sudan is subsistence-oriented. Altogether an output of 764 000 t of vegetables can be estimated for 1983, but production has been increasing steadily.

Table 3 presents the area, yield per unit area and season of production of the important vegetables produced in Sudan. With regard to area, onion ranks first, followed by tomatoes. Also widely grown are okra, cucurbits and eggplant. Onion is grown all over the country but is concentrated in the Central and Northern States. It occupies about 25% of the area under vegetable production. The main onion production period is the cooler season, from October to April. Tomato is grown almost all over the country, along the banks of the Nile and other rivers and in the irrigated schemes. Production of tomatoes is concentrated in the cooler winter season. Cucurbits are warm-season crops which are grown almost everywhere in the Sudan. Watermelons and pumpkins are popular in Western Sudan and are extensively grown during the rainy season in Kordofan.

Table 3. Production statistics for the common cultivated vegetable crops of Sudan.

Crop	Area ('000 ha)	Average yield (t/ha)	Optimum growing season
Onion	40	20	Winter
Tomato	30	5	Winter
Watermelon	10	20	Summer, autumn
Corchorus	10	20	Summer, winter
Cucumber	6	10	Summer, autumn
Okra	5	4	Summer, autumn
Eggplant	5	20	Winter, autumn
Hot pepper	5	1	Winter, autumn
Portulaca	3	20	Summer, winter
Eruca	3	10	All year
Pumpkin	2	24	Summer, autumn
Cantaloupe	1	6	Summer, autumn
Radish	0.5	6	Winter

Okra and the leafy vegetables like Corchorus and Portulaca are very popular in the Sudan and are grown in all parts of the country. They sometimes occur as weeds of cultivation and grow as wild plants in warm areas during the rainy season. These crops can stand the hot climate and are available almost the whole year, except for the cooler months of December and January. Other vegetables, especially the cool-season vegetables, are produced on a limited scale because demand is low.

The average yields for vegetable crops is low compared with the potential. This is attributed to many difficulties, the most important of which are pests and diseases and the unavailability and high cost of pesticides.

Utilization

There is a growing appreciation of vegetables by urban consumers, partly because of increasing awareness of the nutritive value of these species. Table 4 presents the nutritive value of some of the important indigenous vegetables crops grown in Sudan. These crops vary with respect to utilization, use and genetic diversity.

Table 4. The nutritive value of some of the important vegetables grown in the Sudan; composition in terms of 100-g edible portion.

	Food energy (cal)	Moisture (g)	Carbohydrates (g)	Protein (g)	Fat (g)	Crude fibre (g)	Ash (g)	Calcium (g)	Iron (g)	Phosphorus (g)
Onion, green	34	90.5	7.0	0.5	0.6	0.5	0.5	182	1.7	23
Onion, bulb	58	82.4	13.5	1.9	0.1	1.6	0.5	91	1.1	31
Okra	52	82.0	12.7	2.3	0.1	1.6	1.3	152	0.5	99
Watermelon	34	90.3	8.8	0.4	0.1	0.1	0.3	35	2.0	4
Snake cucumber	15	95.0	3.6	0.5	0.1	0.4	0.4	45	0.8	6
Pumpkin	33	89.5	8.0	1.3	0.1	0.6	0.5	22	0.5	37
Cantaloupe	17	94.4	3.4	1.4	0.0	1.4	0.4	25	0.9	3
Corchorus	43	80.2	6.5	7.3	0.2	3.4	2.4	291	5.7	78
Eruca	20	90.8	3.3	2.9	0.1	0.9	2.0	243	7.5	8
Portulaca	21	92.7	3.0	2.6	0.3	0.2	1.2	331	2.0	14
Cowpea (leaves)	35	95.5	5.7	5.8	0.1	0,4	2.5	70	2.0	29
Radish	21	92.7	3.0	2.6	0.3	0.2	1.2	331	2.0	19

After Boutros, J.Z. Sudan Food Composition Tables, 2nd ed. National Chemical Lab. Ministry of Health, Khartoum, Sudan.

Abelmoschus sp. Wild okra (sara) grows as a weed of cultivation in rain-fed areas. The fruits are usually dehydrated and used as a dry powder. The leaves are also used as a green vegetable.

Cucumis melo var. agrestis. Tibish also grows wild or cultivated in rain-fed areas. The fruits are consumed fresh like cucumber as a salad.

Amaranthus spp. Lisan elteer grows as a weed and the leaves are cooked as green vegetable.

Corchrus spp. Molokhia grows as a weed and is cooked as a green vegetable.

Sonchus spp. Molieta is a weed of cultivation in rain-fed and irrigated areas. The leaves are consumed as a salad.

Cultivated indigenous crops

Onions. Onions are produced all over the country. The dry bulbs are used for cooking and the green bunching onion as a salad. There are many local types and landraces, with much variation in skin colour, pungency and storability. When the introduced varieties proved not suitable for processing, an improved white variety (Nasi), which is suitable for dehydration, was selected from local material. Three other varieties (Kamlin yellow, Hilu and Saggai improved) have been developed and released to farmers.

Okra. Okra is the most popular vegetable in Sudan. In combination with sorghum bread (ksra), it is the staple food of the Sudanese people. It is used in both the fresh and dry form. The wild type (sara) is usually used as a dry powder while the cultivated type is mainly used fresh. Efforts have started to utilize the great natural variability found in the rain-fed and irrigated types of okra in the country. Some lines from these types showed outstanding performance compared with introduced varieties (Geneif 1984b). Three lines were selected for their high yield and superior market qualities. The three lines were released by the ARC in 1987 under the names Raiba, Higairat and Sennar (Mohammed 1991).

Watermelon. Although exotic varieties of watermelon have been introduced in Sudan, the local indigenous types are still grown under rain-fed conditions in northern Kordofan. These local types are used as a source of water and as feed for animals, and the seeds are collected and sold. Local indigenous types are well adapted and characterized by great variability. Some have tolerance to blossom end rot and do not show premature cracking, a trait which could be utilized in the development of varieties suitable for production in the heavy clays of Central Sudan.

Hot pepper. Hot pepper is an important crop, well known throughout the country. It is used green as a fresh vegetable or red in dried and ground form. Local landraces were found superior to recently "introduced varieties with respect to growth and fruiting habits, fruit quality and pungency. A breeding programme was initiated to characterize and purify these landraces (Geneif 1984).

Snake cucumber. The local indigenous type of snake cucumber (Cucumis sativus var. flexusus) is a very popular salad crop in Sudan. The immature fruit is consumed fresh or pickled.

Leafy vegetables. Corchorus, Portulaca, cowpea leaves and Eruca are the most popular leafy vegetables in Sudan. The first three are consumed after cooking while rocket is a popular salad crop which is used as a substitute for lettuce.

Conservation

The Sudan is a large country with a great diversity of climatic and agro-ecological zones. The country is also very rich in plant genetic resources. However, these plant genetic resources are subject to erosion. This is due to the expansion of mechanized agriculture in the rainlands of Central, Eastern and Western Sudan, the introduction of new improved varieties and the recent severe drought. Efforts to collect and utilize the genetic resources of vegetable started in the mid-1960s, led by individual plant breeders. In 1982, collaboration started between IBPGR and the Agricultural Research Corporation (ARC) of Sudan in collecting and conservation of germplasm of horticultural crops, including vegetables. Exploration and collecting missions were organized to parts of Central and Eastern regions in 1982 (Hassan et al. 1983), parts of Kordofan and Darfur in 1983 (Hassan et al. 1984) and parts of the Northern region in 1984 (Genief et al. 1986). A large number of accessions of wild species and landraces of vegetables were collected (Table 5).

Table 5. Vegetable crops germplasm collections at the Horticultural Germplasm Unit, ARC, Sudan.

Species	Common name (English)	Local name (Arabic)	No. of accessions
Abelmoschus sp.	Okra	Bamia	173
Allium cepa	Onion	Basal	83
Cajanus cajan	Pigeon pea	Adasi	7
Capsicum frutescens	Hot pepper	Shatta	137
Citrullus vulgaris	Watermelon	Bateikh	67
Corchorus olitorius	Jews' mallow	Molkhia	34
Cucumis sp.	Cantaloupe, snake cucumber, etc.	Shamam, Tibish, Agour	46
Cucurbita sp.	Pumpkins	Gara	53
Dolichos lablab	Hyacinth bean	Lubia afin	8
Lycopersicon sp.	Tomato	Tamatin	124
Phaseolus vulgaris	Haricot beans	Fasulia	22
Pisum sativum	Pea	Pisilla	5
Portulaca oleracea	Purslane	Rigla	21
Raphanus sativus	Radish	Figil	30
Solarium melongena	Eggplant	Bazingan	8
Vigna unguiculata	Cowpea	Lubia hilo	25

The material collected so far is now conserved in a small genebank at the Horticultural Research Section of ARC at Wad Medani. The material is stored in sealed laminated aluminium bags in deep freezers at -20° C, with seed moisture content <7.5%.

References

Badry, A.A.K. 1984. Horticulture production in the Sudan, past, present and future. Acta Hort. 143:25-29.

Geneif, A.A. 1984a. Purification and characterization of local hot peppers in Sudan. Acta Hort. 143:161-173.

Geneif, A.A. 1984b. Tapping natural genetic variability of okra in the Sudan. Acta Hort. 143:175-181.

Geneif, A.A., M.K. Ahmed, S.A. El Husseing and H.M.A. Dinnar. 1986. Horticultural germplasm of northern Sudan. Plant Genet. Resour. Newsl. 64:10-13.

Hassan, M.S., H.M.A. Dinnar, S.A. El Hussein, M.K. Ahmed and A.A. Geneif. 1984. Indigenous horticultural germplasm of western Sudan. Plant Genet. Resour. Newsl. 59:4-11.

Hassan, M.S., A.A. Geneif, M.K. Ahmed, S.A. El Hussein, H.M.A. Dinnar and F. Attere. 1983. Horticultural crops collected in sudan. Plant Genet. Resour. Newsl. 56:33-41.

Mohammed, El Tahir Ibrahim. 1991. Okra genetic resources in Sudan. Pp. 34-35 in International Crop Network Series No. 5. IBPGR, Rome, Italy.