1. PRODUCTION AND UTILISATION OF CASSAVA IN UGANDA

1.1. Introduction spread and economic importance

Cassava was introduced to Uganda through Tanzania by Arab traders between 1862 and 1875 (Langlands. 1972). Following its initial introduction, cassava quickly spread to other areas of Uganda. It is currently one of the most important food crops in Uganda. It rank's second to bananas in terms of area occupied, total production and per capita consumption, respectively (Otim-Nape, 1990). It is regarded as the most important and a staple crop by over 50% of the farmers surveyed recently in the eastern, central, southern and northern areas of Uganda (Otim-Nape and Zziwa 1990; COSCA Uganda, 1996)). Over 71% of the farmers interviewed grew cassava as a subsistence crop. In addition to subsistence, some 19 and 9% of the farmers grow the crop for cash or other uses, respectively (Otim-Nape and Zziwa, 1990). Drinks, animal feed and use of brewing waste as a cementing agent in local construction are other uses of cassava (Otim-Nape and Zziwa, 1990).

Traditional cash crops (cotton, coffee, and tea) which were formerly the main source of income for the rural farmers of Uganda have declined in status in recent years because of poor marketing system and unattractive prices (Ocitti p'Obwoya and Otim-Nape 1986). This has led to the emergence of cassava as the main source of income for over 60% of rural farmers who regard it as a 'new' cash crop in their farming systems (Ocitti p'Obwoya and Otim-Nape, 1986). In most cases the tubers are sold while the crop still stands in the field and the buyers, usually traders or ordinary consumers from within the village, are responsible for harvesting (Ocitti p'Obwoya and Otim-Nape, 1986).

1.2. Production Trends

Since its introduction, cassava has been quickly adopted and its production expanded rapidly. Cassava cultivation increased greatly during the outbreak of the tropical migratory locust (Locusta migratoria migratoriodes S&F) from 1931 to 1933 (Jameson, 1964). Increases also occurred after the droughts of 1939 and 1941 when it became imperative to conserve local foods during the war (Jameson, 1964). The outbreak of African cassava mosaic virus and the shortage of food in some parts of Uganda notably Teso (now Kumi and Soroti districts) in 1943-44 encouraged an eradication campaign and introduction by the district councils of a by-law which made it mandatory for each farmer to grow at least 0.4 ha of cassava mosaic resistant varieties as a safeguard against famine.

The high yield ability of the crop and flexibility of the crop in the farming and food systems, abilities to do well in marginal and stressed environments, its abilities to give satisfactory yields where most other crops fail, to demand low labour requirements and to be left in situ for over two years without spoilage, and its apparent resistance or tolerance to pests and diseases, particularly locusts (Jameson, 1970) encouraged its rapid spread and adoption and made it an excellent food security crop. Moreover, its value as a famine reserve crop that was available when others were not was appreciated (Jameson, 1970). Consequently, cassava plantings increased rapidly as the crop became a cheap source of food in quantity (Jameson, 1964).

By 1950, 191,200 ha of cassava were grown in Uganda (McMaster, 1962). The land area planted to cassava and production of the crop in the country increased from 0.3 million hectares and 3.0 million metric tonnes in 1981 to 0.4 million hectares and 3.0 million metric tonnes in 1989, respectively. By 1994, an estimated total of c. 3.1 million metric tonnes of the crop were produced from c. 0.4 million hectares of land grown in the country. National and regional production by area and yield per hectare of cassava in Uganda is shown for 1970-1994 (Table 1). National statistics indicate a general increase in area up to 1975 and a general decline up to 1988 which later increased up to 1990. Similarly, production increased up to 1977 followed by a decline up to 1981. It then increased up to 1990, then declined but later picked up by 1993. The causes of these decline are complex and may be due to some or all of the following: poor extension services, acute shortages of agricultural inputs; (mostly hand hoes and animal implements), the 1979 liberation war, and northern insurgency, and frequent occurances of severe epidemics of African cassava mosaic disease (ACMD). Regional production generally followed the national trend. Regions however differ in terms of agro-ecological characteristics, farming and food systems and practices which have a bearing on production.

Table 1: National and regional quantative cassava production trends: 1981-94

Year

National

Eastern

Northern

Western

Central
 

Area

Output Yield

Area

Output Yield

Area

Output Yield Area  Output Yield Area  Output Yield
 

(Million ha)

(Million t)

(MT/ha)

(Million ha)

(Million ha)

(MT/ha)

(Million ha)

(Million ha)

(MT/ha) (Million ha) (Million t)  (MT/ha) (Million ha) (Million t) (MT/ha)

1970

0,6

2.6

4,3

0.1

0.6

6.2

0.2

1.3

7.6

0.0 0.2

6.7

0.1

0.3

5.8

1971

0.5

2,4

4.8

0.1

0.5

3.8

0.2

1.6

6.9

0.1 0.1

1.7

0.1

0.2

2.7

1972

0.4

2.7

7.1

0.1

0.6

5.3

0.2

1.5

9,5

0.1 0.3

4.5

0.0

0.3

7.5

1973

0.5

2.1

4.4

0,1

0.5

4.0

0.2

1.1

5.2

0.1 0.2

3.5

0.1

0.3

3.6

1974

0.5

2.4

4.8

0.1

0.6

6.0

0.1

1.1

8.5

0.1 0.2

2.6

0.1

0.4

3.3

1975

0,6

3.0

4.8

0.2

0.8

3.8

0.2

1.6

7.1

0.1 0.2

2.5

0.1

0.4

4.0

1976

0.5

2.8

5.5

0.2

1.0

4.3

0.2

1.0

6.3

0,1 0.2

4,4

0.1

0.6

8.3

1977

0,5

3.0

5.5

0.3

1.3

4.9

0.2

0.9

5.3

0.0 0.2

4,2

0.1

0.6

8.8

1978

0.5

2.0

3.8

0.2

0.6

3.5

0.2

0.6

3.4

0.1 0.1

2.4

0.1

0.5

7.3

1979

0.3

2.1

6.5

0.1

0.7

5,3

0.1

1.0

9.2

0.0 0.1

3.4

0.0

0.3

5.9

1980

0,3

2.1

6.9

0.1

0.5

6.9

0.1

0.6

6.9

0.0 0.2

6.9

0.1

0.5

6.9

1981

0.3

3.0

9.7

0.1

0.8

9.7

0.1

1.1

9.7

0.0 0.3

9.7

0.1

0.7

9.7

1982

0.3

3.1

9.4

0.1

0.8

9.5

0.1

1.2

9.5

0.0 0.4

9.5

0.1

0.7

9.5

1983

0.4

3.2

6.7

0.1

0.8

8.7

0.1

1.2

8.7

0.1 0.4

8.7

0.1

0.8

8.7

1984

0.4

1.9

4.7

0.1

1.0

7,5

0.1

1 . 0

7.5

0.1 0.4

7.5

0.1

0.6

7.5

1985

0.4

1.7

4.3

0.1

0.7

9.0

0.1

1.0

9.0

0.0 0.3

9.0

0.1

0.6

9.0

1986

0.4

1.9

5.2

0.1

1.1

8.0

0.1

0,9

6.0

0.0 0.4

6.0

0.1

0.5

6.0

1987

0.3

3.1

9.0

0.1

1.1

9.0

0.1

1.0

9.0

0.0 0.4

9.0

0.1

0.6

9.0

1988

0.4

3.3

9.1

0.1

1.2

8.9

0.1

1.0

9.0

0.1 0.5

9.5

0.1

0.6

9.4

1989

0.5

4.5

9,6

0.2

1.6

9.1

0.2

1.8

9.1

1.0 0.7

9.1

0.0

0.4

9.1

1990

0,5

4.7

9,1

0.2

1,7

9.2

0.2

1.9

9.2

1.0 0.6

9.2

0.0

0.4

9.2

1991

0.4

3.2

6.3

0.1

1.2

8.3

0.2

1.3

8.3

0.0 0.2

8.6

0.1

0.4

8.3

1992

0,4

2.9

8.0

0.1

1.1

8.0

0.1

1.0

7.6

0.0 0.2

8.0

0.0

0.4

7.6

1993

0.4

3.1

8,5

0,1

0.3

2.5

0.2

1.1

6.6

0.0 0.1

6.5

0.0

0.2

5.6

1994

0,4

3.1

6.2

0.1

0,3

2.4

0.1

1.1

8.4

0.0 0.1

8.5

0.0

0.3

8.2

Total

10.6

69.8

170.2

3.2

21.4

163.8

3.7

29.3

195.7

3.0 7.2

163.8

1.8

11.6

183.1

Cassava is grown throughout Uganda (Appendix Tea - 1c The districts of Mbale, Iganga, Apac, Kamuli. Lira. Tororo and Kumi are the leading producers. Cassava production is low in the districts of central region where bananas and plantains have been the traditional staple food crops. Production of cassava in the central region is expanding rapidly as farmers have realised the advantages of cassava compared to bananas whose production is decreasing due to declining soil fertility and the effects of pests and diseases (COSCA, Uganda 1996).

1.3 Production practices

Cassava land holdings vary from 3 to 15 ha per farming family (Ocitti p' Obwoya and Otim-Nape, 1986) and land is either inherited from parents or is purchased, borrowed or rented (Otim-Nape and Zziwa, 1990). As a change from past practices, most farmers now begin their crop rotations with cassava (Otim-Nape and Zziwa, 1990). A majority of farmers plant cassava on land of average fertility while only a minority, use either poor or very good land (Otim-Nape and Zziwa, 1990). Most planting is done in the first rather than in the second rains of the year. Over 95% of the farmers sampled select and plant 30-40 cm lengths of matured stems of preferred varieties. Spacings of 0.75m x 0.75m - 2.Om x 2.Om are used and are usually irregular depending on the other crops grown as intercrops.

As in many other parts of Africa, intercropping is a common practice with cassava in Uganda. Common crop mixtures are cassava/cereals/legumes (i.e. cassava/maize or sorghum or finger millet/beans, or groundnuts or cowpeas or soya beans) and cassava/ bananas/coffee (Otim-Nape and Zziwa, 1990). The cereals or legumes are planted two to three weeks before or after planting cassava, the spacing of cassava being wider (1.5 x 1.5m) than for the normal sole crop. For the cassava/banana/coffee mixtures, cassava is introduced into the system when the ban~ or coffee are still young. Each row of bananas or coffee is planted to two or three rows of cassava planted at a wider spacing (about 2.5m x 2.5m to 2.Om x 2.0 m).

1.4. Utilisation

Cassava plays an important role in the national diet and contributes a substantial
proportion of the caloric requirements of the population. Peeled sweet cassava roots are eaten raw. boiled. fried. roasted or, after drying and pounding, it is turned into a paste. Peeled bitter cassava are turned into flour after a solid state fermentation process, or after steeping in water (wet fermentation) and subsequent sun-drying. Also boiling the whole pieces, immediately after soaking. occurs. Especially bitter cassava is preferred for brewing local beer and distilling Waragi, (a local gin).

According to studies (COSCA, Uganda 1996; Otim-Nape and Zziwa, 1990), carried out in selected villages in Uganda, boiled fresh cassava was regarded as the most important product; followed by flour in 16% of the villages and fermented drinks in 12.5% of the villages. However, flours were the most important cassava product in 65% of the villages where cassava is the second most important crop; and in 52% of the villages where cassava is the third most important crop; 32% of these third ranked villages reported drinks as their most important cassava product. These results indicate that while boiled cassava is the preferred form of cassava product, flours and drinks are also produced in significant quantities. Local gin, (enguli, waragi) are produced from dried cassava chips ground into flour, brewed and distilled. A flow diagramme showing the stages for processing different products is shown in Figure 2.

1.5. Trends in cassava demand

Analyses of food supply and demand shows that up to 1994 on average, Uganda had a surplus in cassava (Table 2). The period 1981 to 1994 (data not shown) shows gradual increase in surplus. From 1985 however, the surplus declined steadily. For instance,  between 1981 and 1987, the surplus level was 1.231 million mt per annum. This level however declined to about 677,000 mt per annum between 1987 and 1994. The projected national cassava supply, demand and surplus figures (in million tons) are given (Table 2).

The main reason for decline in levels of surplus is the outbreak in 1989 of the cassava mosaic disease which destroyed the crop and also affected productivity in most of the   cassava growing areas. This has also affected human consumption levels. However, despite the average drop, increase is envisaged as better yielding and mosaic resistant varieties are planted and come into the market. Cassava used to be the leading food item in the northern and eastern Uganda. It is expected that with multiplication and distribution of resistant varieties, cassava.output (and consumption) will significantly, increase in these regions.

Although population growth is estimated at about 2.5 percent per year, per capita human food consumption in the last five years declined (Table 3). Unless this trend is reversed, increase in total cassava demand will be lower than increase in cassava supply. necessitating processing, the use of cassava as industrial raw materials and for animal feed.

Table 2: The projected national cassava supply, demand and surplus figures (in million tons)

Year

Cassava supply

Cassava demand

Surplus

1995

2.137

2.185

-49

1996

2.210

2.269

-61

1997

2.381

2.358

22

1998

2.567

2.449

117

1999

2.768

2.545

222

2000

2.985

2.643

340

Figure -2. Processing steps for var ious products from cassava roots.


 

Table 3: Quantitive food demand trends for cassava (1981-1994)

year population
(millons)
human consunption
(million tons)
industry
use
(ton)
total
demand
(million tons)
per capito consuption (kg per head)

EASTER REGION

1991

3.31

0.54

0

0-54

1-64

1982

3.38

0.55

0

0.55

164

1983

3.46

0.57

0

0.57

164

1994

3.53

0.58

0

0.58

164

1985

3.61

0.59

0

0.59

164

1986

3.69

0.59

0

0.59

160

1987

3.77

0.62

0

0.62

164

1998

3.85

0.63

0

0.63

164

1989

3.94

0.63

0

0.65

164

1990

4.02

0.66

0

0.66

164

1991

4.13

0.59

0

0.59

142

1992

4.22

0.60

0

0.60

142

1993

4.31

0.61

0

0.61

142

1994

4,41

0.63

0.63

142

NORTHER REGION

1981

2.49

0.48

0

0.48

195

1982

2.54

0.50

0

0.50

195

1983

2.60

0.51

0

0.51

195

1994

2.67

0.52

0

0.52

195

1985

2.73

0.53

0

0.53

195

1986

2.79

0.55

0

0.55

1987

2.86

0.56

0

0.56

195

1988

2.93

0.57

0

-0.57

195

1985

1.00

0.59

0

0.59

195

1990

3.07

0.60

0

0.60

195

1991

3.15

0.47

0

0.47

148

1992

3.23

0,47

0

0.47

145

1993

3.31

0.49

0

0.49

148

1994

3.38

0.50

0

0.50

148

WESTERN REGION

1981

3.39

0.39

0

0.39

115

1992

3.48

0.40

0

0.40

115

1983

3.58

0.41

0

0.41

115

1994

3.67

0.42

0

0.42

115

1995

3,77

0.43

0

0.43

115

1996

3.99

0.44

0

0.44

1-15

1987

3.98

0.46

0

0.46

115

1989

4.09

0.47

0

0.47

115

1989

4.20

0.49

0

0.49

115

1990

4.31

0.49

0

0.49

1-15

1991

4.43

0.38

0

0.38

8-5

1992

4.55

0.79

0

0.39

95

1993

4.67

0.40

0

0.40

95

1994

4.80

0.41

0

0.41

8-5

CENTRAL REGION

1981

3.21

0.38

0

0.39

119

1992

3.30

0.39

0

0.39

119

1983

3.40

0.41

0

0.41

119

1984

3.51

0.42

0

0.42

119

1985

3.61

0.43

0

0.43

119

1998

3.72
0.44

0

0.44

1-19

1987

3.83

0.46

0

0.46

119

1988

3.95

0.47

0

0.47

119

1989

4.06

0.48

0

0.49

119

1990

4.19

0.50

0

0.50

119

1991

4.07

0.52

0

0.52

128

1992

4.19

0.54

0

0.34

129

1993

4.32

0.55

0

0.55

129

1994

4.45

0.57

0

0.57

129

UGANDA

1980

12.63

1.73

0

1.73

137

1981

13.33

1.83

0

1.83

137

1982

13.69

1.99

0

1.99

137

1983

13.94

1.91

0

1.91

137

1984

14.19 1.94

0

1.94

137

1985

14.49

1.99

0

1.99

137

1996

14.99

2.04

0

2.04

137

1987

15.30

2.10

120

2.10

137

1988

15.72

2.15

122

2.15

137

1989

6.15

2.02

145

2.02

125

1990

6.60

2.07

140

2.07

125

1991

6.67

2.08

194

2.08

125

1992

17.52

2.19

171

2-19

125

1993

18.00

2.25

157

2:25

125

1994

18.49

2.31

195

2.31

125

Source. EPAU 1996

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