INTRODUCTION
Rice is a staple food in many countries of Africa and constitutes a major part of the diet in many others. During the past three decades the crop has seen consistent increases in demand and its growing importance is evident in the strategic food security planning policies of many countries. With the exception of a few countries that have attained self-sufficiency in rice production, rice demand exceeds production and large quantities of rice are imported to meet demand at a huge cost in hard currency. Africa consumes a total of 11.6 million tonnes of milled rice per year (FAO, 1996), of which 3.3 million tonnes (33.6 percent) is imported. As many as 21 of the 39 rice-producing countries in Africa import between 50 and 99 percent of their rice requirements. The distribution of rice importation on a regional basis appears skewed, with the North and Central Africa regions setting the lower (1.7 percent) and upper (71.7 percent) limits, respectively.Africa's inability to reach self-sufficiency in rice is the result of several major constraints in the rice industry which require urgent redress to stem the trend of over-reliance on imports and to satisfy the increasing demand for rice in areas where the potential of local production resources is exploited at very low levels.
RICE PRODUCTION, CONSUMPTION AND SELF-SUFFICIENCY IN AFRICA
Rice production
Africa produces an average of 14.6 million tonnes of rough rice per year (1989-1996) on 7.3 million ha, equivalent to 2.6 and 4.6 percent of the world's total production and rice area, respectively. West Africa has the greatest rice area (Figure 1) in Africa (56.5 percent), i.e. about 3.7 million ha.
FIGURE 1: Rice area by region, Africa
(42 percent); North Africa (32 percent); East Africa (23.8 percent); Central Africa (1.2 percent); and
southern Africa (1 percent).
FIGURE 2: Rice area trends in Africa
FIGURE 3: Regional trends in rice area, Africa
FIGURE 4: Rice production by region, Africa
FIGURE 5: Grain yield trends in Africa
Rice consumption
Africa consumes 11.5 million tonnes of rice per year (FAO, 1996), 33.6 percent of which is imported. Between 1989-91 and 1995, the rice import trends showed a small decline of 55 000 tonnes, while paddy production increased by 2.3 million tonnes over the same period (Figure 6).
FIGURE 6: Paddy production trends in Africa
FIGURE 7: Regional trends in rice imports, Africa
TABLE 1
| ||||
Rice self-sufficiency (percent) in West Africa
| ||||
Country
|
1960-641
|
1970-741
|
1980-841
|
1989-962
|
Benin
|
12.4
|
26.7
|
22.9
|
17.7
|
Burkina Faso
|
83.1
|
74.3
|
34.2
|
39.3
|
Chad
|
-
|
-
|
-
|
75.0
|
Côte d'Ivoire
|
70.1
|
71.3
|
42.0
|
62.8
|
Gambia
|
84.8
|
87.1
|
23.0
|
18.0
|
Ghana
|
28.8
|
48.3
|
41.2
|
15.1
|
Guinea
|
83.1
|
82.9
|
74.4
|
56.7
|
Guinea-Bissau
|
94.6
|
47.4
|
60.1
|
55.0
|
Liberia
|
63.5
|
71.1
|
64.1
|
38.5
|
Mali
|
100.0
|
69.7
|
45.2
|
48.9
|
Mauritania
|
4.2
|
5.3
|
10.0
|
54.1
|
Niger
|
63.7
|
52.8
|
26.7
|
49.6
|
Nigeria
|
98.7
|
98.8
|
51.4
|
83.8
|
Sierra Leone
|
92.6
|
91.4
|
77.4
|
55.0
|
Senegal
|
27.8
|
23.3
|
15.5
|
20.3
|
Togo
|
70.8
|
70.0
|
28.4
|
56.0
|
Average
|
72.2
|
71.5
|
48.3
|
46.6
|
1 Nyanteng, 1998.
2 FAO, 1995.
|
TABLE 2
| |||||||
Rice self-sufficiency of African regions, 1996
| |||||||
Central Africa
|
Self-sufficiency (%)
|
East Africa
|
Self-sufficiency (%)
|
Southern Africa
|
Self-sufficiency (%)
|
Northern Africa
|
Self-sufficiency (%)
|
Burundi
|
83.1
|
Kenya
|
41.0
|
Angola
|
94.9
|
Algeria
|
2.5
|
Cameroon
|
23.2
|
Madagascar
|
96.6
|
Mozambique
|
98.8
|
Egypt
|
99.99
|
Central African Rep.
|
83.5
|
Malawi
|
90.5
|
South Africa
|
0.93
|
Morocco
|
99.97
|
Congo
|
1.9
|
Somalia
|
2.9
|
Swaziland
|
99.1
|
||
Dem. Rep. of Congo
|
37.6
|
Sudan
|
0.4
|
Zambia
|
100.0
|
||
Gabon
|
2.0
|
United Rep.Tanzania
|
84.9
|
Zimbabwe
|
0
|
||
Rwanda
|
34.2
|
Uganda
|
91.6
|
RICE POTENTIAL IN AFRICA
The potential arable land in Africa is 637 million ha (Okigbo, 1982), and about 68 percent of the total area is in reserves. Africa therefore has great potential for expanding its agricultural production in general and rice in particular. Rice production is most extensive in rainfed (upland) ecosystems (which account for60 percent of the total rice area) and, in these areas, rice competes with several other important staple crops, such as maize, sorghum, millet, cassava, yam, coco-yam, plantain and banana, as well as such cash crops as coffee, cocoa, citrus and cola. However, as these crops increase in economic importance, the rice area will diminish because rice is the lowest-yielding crop in that ecology. The wetlands, including irrigated ecologies, will therefore become increasingly important as these ecologies are more suitable for rice production than they are for other upland crops.
The wetlands in tropical sub-Saharan Africa cover a total area of 2.4 million km2 (24 million ha) and consist of four categories (Table 3): coastal wetlands (165 000 km2); inland basins (1.07 million km2); river floodplains (300 000 km2); and inland valleys (850 000 km2) (Andriesse, 1986). Osborn (1953), quoted by Guthrie (1985), pointed out that Africa, which represents one-fifth of the world's land, is about one-third desert and only 0.1 percent of its total land area is irrigated. Wetland soils occupy a larger area than irrigated land but, compared with the total, this area is still quite small. There are, however, several large areas, principally in Central Africa, where wetland soils are common and are dominated by Tropaquepts and Tropoquents of limited suitability for conversion to productive use.
TABLE 3
| |||
Wetlands in tropical sub-Saharan Africa (2.4 million km2)
| |||
Category
|
Area ('000 km2)
|
% of total wetlands
|
% of total area
|
Coastal wetlands
|
165
|
7
|
1.5
|
Inland basins
|
1075
|
45
|
9.0
|
River floodplains
|
300
|
12
|
2.5
|
Inland valleys
|
850
|
36
|
7.0
|
Source: Andriesse, 1986.
|
Many rivers in Africa (e.g. the Gambia, Niger, Benue, Zaire, Zambia, Limpopo, Tana, White and Blue Nile and Chari rivers) have well-developed large floodplains in their central and lower stretches, and these are suitable for rice production (Andriesse, 1986).
RICE ECOSYSTEMS
Rice is produced in Africa in the following five main ecosystems:- dryland (rainfed upland);
- hydromorphic (rainfed lowland);
- mangrove swamp;
- inland swamp;
- irrigated ecology.
The specific constraints will be discussed under each ecosystem, while the non-specific ones will be described generally.
Dryland rice ecosystem (strictly rainfed)
Description. This is the most extensive rice ecosystem in Africa, so it has a great influence on the total rice output. It occurs in the uppermost part of the topo-sequence and is more important in West Africa than in other African regions. In West Africa it covers 57 percent (i.e. 1.8 million ha) of the total rice areaand accounts for 44 percent of regional production (Table 4). The major producers in West Africa include the following countries: Sierra Leone, Côte d'Ivoire, Liberia, Guinea-Bissau and Nigeria.
TABLE 4
| ||||
Rice area, yield and production by ecosystem in West Africa (1980-84 and 2000)
| ||||
Environment
|
Area
|
Yield
|
Production
| |
('000 ha)
|
(%)
|
(tonnes/ha)
|
('000 tonnes)
| |
1980-84
| ||||
Upland/hydromorphic
|
1 490
|
57
|
1.0
|
1 490
|
Hydromorphic/inland swamp
|
530
|
20
|
1.4
|
742
|
Irrigated humid zone
|
119
|
5
|
2.8
|
333
|
Sahel
|
112
|
4
|
2.8
|
313
|
Mangrove swamp
|
193
|
7
|
1.8
|
347
|
Deepwater/floating
|
190
|
7
|
0.9
|
171
|
Total
|
2 631
|
100
|
-
|
3 396
|
20001
| ||||
Upland/hydromorphic
|
2 160
|
59
|
1.0
|
2 160
|
Hydromorphic/inland swamp
|
760
|
21
|
1.4
|
1 064
|
Irrigated humid zone
|
185
|
5
|
2.8
|
518
|
Sahel
|
155
|
4
|
2.8
|
434
|
Mangrove swamp
|
193
|
6
|
1.8
|
347
|
Deepwater/floating
|
190
|
5
|
0.9
|
171
|
Total
|
3 643
|
100
|
-
|
4 694
|
1 Projections.
Source: WARDA, 1993. |
- It leads to rapid deforestation and destruction of watersheds.
- It is essentially a low-input ecosystem, which results in poor paddy yields (i.e. 1 tonne/ha) for the following reasons: - there is little or no fertilizer application in this ecosystem;
- It is wasteful of land resources since increased production is achieved mainly through area expansion rather than through increased yield per unit area.
- It is ultimately unsustainable as a result of increased population pressures on the land which have led to reduced fallow periods and poor natural regeneration of soil fertility, on which the whole culture is pivoted.
- weed control is essentially manual and is usually delayed, resulting in serious yield reduction;
- drought results in total crop failure;
- diseases, such as blast, leaf scald, brown spot and sheath rot, cause considerable loss in yields if not controlled;
- the major pests include birds, mice and the large rodents known as "grasscutters" (Thryonomis swindarianus), which cause serious destruction of rice.
- practise rice-based cropping systems that include grain legumes to improve soil fertility;
- incorporate crop residue into the soil to improve the soil organic matter content and fertility;
- encourage the use of fertilizers and herbicides to improve growth and weed control;
- adopt erosion control methods to prevent rapid soil degradation;
- adopt water-harvesting methods to reduce the risk of drought and enhance crop yields;
- evolve upland rice varieties that are drought-tolerant and high-yielding.
Lowland/hydromorphic
Description. This ecosystem occurs from the mid-slope to the valley bottom in the topo-sequence. The rice crop here may obtain water from three sources - direct rainfall, high water table and surface water - depending on its location in the topo-sequence. The main hydraulic characteristic of this ecosystem is the fluctuating water table, caused by cyclical swelling and receding water levels of rivers during the rains.It is estimated that a total of 130 million ha of inland valleys are available for cultivation in Africa, 19 million ha of which (i.e. 14.6 percent) occur in West Africa. Depending on the level of technology, soil conditions and socio-economic factors, the range of yields is wide (between 1.4 and 5 tonnes/ha) but generally higher than in the strictly upland ecosystem (Table 4).
Constraints. As a result of poor drainage, high levels of Fe2+ and Mn2+ may occur and often produce iron toxicity symptoms. Iron toxicity has been observed in many West African countries, including Benin, Burkina Faso, Côte d'Ivoire, Liberia, Nigeria, Senegal and Sierra Leone (Virmani, 1979). Yield losses of between 12 and 88 percent have been observed as a result of iron toxicity (Gunawardena, Virmani and Sumo, 1982). Non-tolerant lines could result in 100 percent yield reductions. A major physical constraint in this ecosystem are the uncontrolled floodwaters that sometimes inundate the crop or produce flash floods, which may carry away the harvest.
Mangrove swamps
Description. Mangrove swamps occur mainly along the West African coast and cover a total area of 1.2 million ha, 193 000 ha (i.e. 16 percent) of which have been developed for cultivation (Table 4).The mangrove swamps have high salinity levels caused by seawater intrusion brought in by tidal waves from the sea, although nearly all mangrove swamps enjoy a salt-free period during the rainy season as freshwater floods wash the land. This period shortens, from over six months to under four, with increasing proximity to the sea, but is generally long enough to allow a crop of rice to grow.
Constraints. About 84 percent of the potential area is uncultivated, but its development is likely to be very slow because of the following discouraging factors:
- the high cost of development;
- inadequate tools for development ;
- long distances between the swamps and villages making access difficult;
- shortage of labour and its attendant high cost;
- the control of mangrove clearing for ecological reasons.
Major constraints in the mangrove swamps include:
- lodging and silting, caused by tidal movements;
- adverse soil conditions, especially acidity and salinity, as well as iron, aluminium and manganese toxicity;
- weeds, especially in the swamps further from the sea;
- pests, among which crabs are by far the most damaging, although stem borers and rice bugs are also important;
- diseases, including blast and brown spots, which can be severe.
Irrigated ecosystem: humid zone
Description. The irrigated ecosystem provides the best conditions for rice cultivation because of the better control of water compared with other ecologies. However, the importance of the irrigated ecosystem in rice production in Africa is relatively small (11 percent of the rice area) except in a few countries, such as Egypt (100 percent of the rice area), Madagascar (31 percent), the Niger (100 percent) and Mauritania (100 percent) (WARDA, 1993). The yield range is the highest of all the ecosystems (from 3.5 to 7 tonnes/ha).The vast wetlands in the West and East Africa regions are yet to be fully developed. In West Africa, the irrigated ecosystem is expected to increase from 231 000 ha (1980-84) to 340 000 ha by the year 2000 (Table 4). The projection is based largely on the activities of Nigeria and Côte d'Ivoire which are developing their wetlands and irrigated ecosystem.
Constraints. The major physical constraints include nutrient deficiencies (i.e. N, P, S and zinc [Zn]), toxicities (Fe, Mn and Al) and acidity.
The biological constraints include: weed buildup (of grasses, broadleaves, sedges and wild rice); diseases (rice yellow mottle virus, blast, glume discoloration, sheath rot and bacterial leaf blight); and insects (gall midge, white stem borer and grain bugs). In Africa, 15 species of insects are considered major pests of rice and they are classified into four groups: stem borers; leaf feeders; grain suckers; and stem and leaf suckers. Most damage to rice is caused by stem borers. Additional constraints are: pests (birds, rodents and crabs); germplasm (poor input responsiveness of local varieties and slow release of improved varieties); and health hazards (buildup of vectors of malaria and schistomiasis parasites). The average yield loss that can be attributed to insects, disease and weeds is about 33.7 percent of the potential yield (Barr, Koecher and Smith, 1975).
GENERAL CONSTRAINTS ACROSS ECOSYSTEMS
The general constraints affecting rice production in Africa include the following:- unreliability of rainfall in the transitional zones of West, Central and East Africa;
- serious destruction of rice fields by cyclones in Madagascar (Rakotonjanahary, 1989);
- yield losses caused by low solar radiation owing to clouds during August in West Africa (Posner, 1978);
- extremes of temperature (< 20oC and > 35oC) which result in yield losses in Madagascar, Central, East and southern Africa;
- absence of suitable varieties to withstand these stresses (Yoshida, 1978; Masajo et al., 1985; Kadena and Beachell, 1974; and Alluri, Mahsatra and Lawson, 1979);
- unfavourable government policies that affect agriculture in general and rice in particular with regard to the following: - resource allocation;
- cropping priorities;
- provision of adequate credits;
- low interest rates;
- creation of incentives and input subsidies;
- pricing and marketing policies;
- provision of modern milling facilities to improve rice milling quality and out-turn.
RICE DEVELOPMENT POLICIES, CONSTRAINTS AND PRODUCTION STRATEGIES IN AFRICA
The national policies on agricultural food production across many African countries explicitly or implicitly address the need to increase food production to meet the food security objectives of each country and give priority to achieving self-sufficiency in staple food production (e.g. cereals, and roots and tubers) in each country. The level of rice developments in the regions is closely related to:- the status of the crop as a staple (nearly all the major rice-producing countries, i.e. Egypt, Madagascar, Sierra Leone, Senegal, Côte d'Ivoire, Liberia, Guinea and Nigeria, consume rice as a staple);
- the status of the crop as a major cash crop;
- the suitability of the prevailing ecosystem for large-scale rice production.
- It is generally accepted that rice is a major food crop whose importance as a staple is rapidly growing in Africa.
- Africa imports nearly 40 percent of its rice requirements at a cost of US$1.1 billion per year.
- Africa has vast areas of land that are suitable for rice cultivation but are currently underutilized.
- Africa has large bodies of water that could be developed for rice irrigation.
- The climate of Africa, except for a few cold and some extremely hot environments, is generally suitable for the cultivation of rice.
- Africa has a vast potential to cultivate rice for local consumption and export if large investments are made to develop the industry, reduce imports and save scarce foreign exchange.
Rice development strategies
Government agricultural policies should be directed towards increased growth of the agricultural sector and increased agricultural contributions to the gross domestic product (GDP). This will require the allocation of more government resources to agriculture and the implementation of policies aimed at solving the problems associated with technical, socio-economic, macro- and micro-economic constraints, with the following objectives:- low-interest credit facilities for farmers;
- easy access to inputs at affordable prices, by reducing import duties on agricultural inputs and eliminating intermediaries;
- improved market infrastructures (i.e. markets, transport, roads and storage);
- improved roads and transport facilities within the farming areas to ease movement of labour, which is usually in short supply during the peak farming periods, and to prevent women, who are key personnel in many farming communities, from having to walk long distances to farms;
- infrastructures (e.g. modern mills) for better post-harvest handling of paddy, which will increase milling out-turn and the quality of the product and lead to better prices and incomes for producers;
- adequate funding for research and extension institutions, to support farmers as they increase their output, through the following interceptions: - development of improved high-yielding varieties for farmers;
- optimization of the use of agro-inputs (e.g. fertilizer and herbicides);
- development of simple farm tools to help farmers reduce the tedium of the numerous labour-intensive activities involved in the production of rice.
- rapid expansion of the area covered by the most favourable ecology or ecologies (e.g. inland valleys, rainfed/lowland/hydromorphic, etc.);
- implementation of efficient, up-to-date production technologies (i.e. improved seeds, optimum fertilizer rates, weed control methods, etc.);
- improvement of post-harvest handling (i.e. drying, milling and packaging for market).
- successful breeding of varieties that fit the major production ecologies and suit consumers' tastes;
- higher yields per unit area in all of the ecosystems;
- intensification of the wetland ecosystem and consequent reduction of the area to stem the system of shifting cultivation which is becoming increasingly unsustainable;
- development of small-scale irrigation schemes, which are simple and inexpensive to construct, especially in the vast inland valleys that are found all over Africa which, generally, have higher fertility levels and better than average water availability compared with the uplands;
- improved price competitiveness for local rice against high-quality imports from the United States and Thailand by providing modern mills equipped with paddy separators and rubber rollers for higher milling out-turns (65 to 70 percent) than currently obtained (50 to 65 percent) in many countries.
Rice development support services
Coordinating rice research programmes in Africa. Rice research in Africa is organized on a subregional basis and enjoys assistance from the International Agricultural Research Centres (IARCs) such as the West African Rice Development Association (WARDA), the International Institute of Tropical Agriculture (IITA), IRRI and the International Centre of Insect Physiology and Ecology (ICIPE), which collaborate with the National Agricultural Research Systems (NARS) of the various countries.Varietal development programmes in Africa have been greatly supported by IITA and IRRI (e.g. IRTP-Africa and INGER) collaborative studies. A WARDA-coordinated collaborative study with INGER and NARS is presently seeking control of rice yellow mottle virus at Gagnoa (Côte d'Ivoire) in sub-Saharan Africa (Sy, Alluri and Akator, 1994).
Detailed characterization of the various ecosystems and effective coordination of research within the region will avoid expensive repetitions and promote rapid development of the rice industry.
Future research needs. In order to enhance rice production, while preserving the integrity of the environment, there should be intensification of research in the following areas:
- control of rice yellow mottle virus;
- control of the African rice gall midge;
- development of an effective rice-based cropping system to improve soil fertility and pest and disease control, together with intensification of the wetland ecology to stem rapid deforestation;
- breeding of suitable varieties for cold tolerance and heat tolerance;
- increased use of organic manures to reduce overdependence on inorganic fertilizers;
- post-harvest processing to improve milling out-turn and quality of the product.
CONCLUSIONS
Among the 39 African countries that produce and consume rice, only ten have attained any appreciable levels of rice self-sufficiency (75 to 99.9 percent), while the remaining 29 are heavy importers with self-sufficiency levels ranging between 0 and 62.8 percent. Based on WARDA statistics (1973-1992), the projected rice demand by the year 2000 will be 13.08 million tonnes, representing an increase of 1.94 million tonnes since 1996. The generally low production technology practised in Africa results in low yields, which are exacerbated by the several constraints discussed. Unless Africa invests more in research to find appropriate technologies that will remove several of the major constraints to rice production in the various ecologies, the region will have to increase imports to satisfy the growing demand for rice that is expected in the twenty-first century.Since the upland/hydromorphic ecology is the most extensive in Africa and the lowest-yielding, a 30 to 40 percent increase in yield in these areas will have a great impact on production, so their improvement should be a short-term priority. In the long term, Africa should consider the lowland (rainfed) ecology and the vast potential of the inland valleys for intense development. Because of the high cost of development and the generally poor record of irrigation management in Africa, it is prudent to avoid large-scale conventional schemes and concentrate on small irrigation units. These are simpler to manage and could be built around small village communities, thus avoiding labour shortage problems. While seeking to expand rice production, grain cooking qualities should also be improved. Varietal improvement programmes should meet the tastes and demands of the consumers who are the ultimate judges of the success of the programmes.
In the free market system, where local products compete with high-quality imports, farmers' incomes will be determined by the quality of their produce. In this regard, efforts should be made to improve harvesting methods and post-harvest processing by discarding obsolete mills and introducing modern rubber-roller mills for high out-turn and a high percentage of head rice.
Last, but not least, the onus is on governments to provide the necessary enabling environments through national agricultural policies and by providing more resources for the development and expansion of the industry in order to achieve a high level of rice self-sufficiency.
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