INTERNATIONAL POTATO CENTER: WORLD POTATO ATLAS
ETHIOPIA
HISTORY AND OVERVIEW
Following the introduction of the potato to Ethiopia in 1858 by a German immigrant, Wilhelm Schimper, adoption by Ethiopian farmers occurred very gradually for several decades (Kidane-Mariam 1980). The first available potatoes were probably of a very limited genetic base, hence vulnerable to diseases and pests. Cultivation was limited to potatoes growing voluntarily in fields in the colder highlands until wider adoption of the potato occurred at the end of the nineteenth century in response to a prolonged famine (Medhin et. al. 2001). B. Laufer reported in the potato section of his 1938 work, The American Plant Migration, that the potato had by then apparently become naturalized in southern Ethiopia and southeastern Sudan.
Potato production has increased considerably through the twentieth century. In 1975, the area of cultivation was estimated at 30,000 hectares, with an average yield of approximately five tons per hectare (Medhin et. al. 2001). However, potato cultivation declined in the early 1980s, due in part to widespread infestation of late blight, Phytophthora infestans (Tesafun 1984). During this period agricultural production in general was disrupted in several areas of the country by drought, famine, and civil war (Wolfe 1988), as various opposition groups fought the Dergue regime which had come to power in the revolution of 1974. Land reform legislation under the Dergue directed the majority of agricultural resources (such as credit, fertilizer, and improved seed) to state farms and cooperatives, likely to the detriment of smallholders who continued to produce most of the nation's food in spite of a lack of investment (Belete et. al. 1991).
Following the 1980s drought and the overthrow of the Dergue regime in 1991, potato production has resumed its upward trend. Medhin et. al. (2001) estimate that the area of cultivation had reached 50,000 hectares by the mid 1980's (an estimate still cited as of 2003 by the United Nations Food and Agriculture Organization (FAOSTAT)), but that by 2001, Ethiopia's potato area had grown to 160,000 hectares, with average yields around eight tons per hectare. An upward trend in potato production might be partly due to the continuing increase in population and subsequent decline in the average size of farm holdings, hence pressure for agriculture to become more labor intensive (Medhin et. al. 2001). These data should be treated with caution, since the potato, in spite of its growing importance to Ethiopia's food security, is still widely regarded as a secondary non-cereal crop for which production data are not well documented.
GEOGRAPHY AND PRODUCTION ZONES
Ethiopia has possibly the highest potential for potato production of any country in Africa. An estimated seventy percent of the country's arable land is potentially suitable to potato cultivation (Yilma 1989). Most of this land is contained in the Central Highlands, at altitudes ranging from 1,500 - 3,000 meters above sea level (masl) and annual precipitation of 600 - 1,200 millimeters (mm) (Medhin et. al. 2001). The highland areas of Ethiopia (defined as land above 1,500 masl) where the potato is generally well suited, cover 44 percent of the nation's area, but include 88 percent of its population and 95 percent of its cropped area (Grepperud 1996).
The Central Highlands are dominated by a lava plateau which is divided by the East African Rift Valley into the Eastern Plateau and the Central Plateau; and the Blue Nile Valley which originates in the Central Plateau, cutting through the western crystalline highlands as it enters Sudan (Albert 1984; Kidane-Mariam 1980). Within these diverse areas, broad climate classification distinguishes dega (cold) zones above 2,500 masl, waina dega (temperate) at 1,800 to 2,500 masl, and quolla (hot) below 1,800 masl.
Rainfall is similarly affected by topography, average annual precipitation generally increasing with altitude. Rains are generally concentrated in the months of June through September, but with considerable spatial and temporal variability (Albert 1984; Kidane-Mariam 1980). Ethiopian farmers distinguish long rains (meher), which generally occur from June to September and provide the main agricultural season, from short rains (belg), from January to June.
- Many maps of more specific classifications — for example by soil types, agro-ecological zones, and land use — are available from the European Digital Archive of Soil Maps, Ethiopia.
Most images are digitized from paper maps, of variable clarity.
- A map of potato distribution in Ethiopia can be found on the Country Maps page.
A brief description of three communities in areas where potatoes are a significant crop serves to illustrate the physical diversity of the country (Borgel et. al. 1980):
- Holetta, approximately forty kilometers (km) west of Addis Ababa on the Central Plateau, is a source of potatoes for Addis Ababa and other urban markets. The area ranges in elevation from 2,000 to 3,000 masl. Shallow alfisols, clay loam in texture, occupy many of the steeper slopes. Lower, gentler slopes are often characterized by deeper clay inceptisols which are well drained and easy to work, but poor in organic matter and nitrogen. Deep, fertile, clay vertisols occur in the lowlands. These are subject to waterlogging and are generally difficult to work. Mean monthly temperatures range from 10.8º C in November to 15.4º C in April with considerable diurnal range. Frost at night in the winter is common. Average annual rainfall is 1,054 mm. Most of this falls from June to September, with moderate rainfall (60-75 mm/month) from March to May, and little precipitation from October to March.
- Awassa, in one of the largest potato producing areas of Ethiopia, is situated about 260 km south of Addis Ababa in the Rift Valley at 1,600 to 1,800 masl. Many of the soils are deep and very fertile, developed on volcanic rocks, ash deposits, and fluvial and lacustrine sediments. The mean annual temperature is 19° C with monthly means ranging from 18.1° C in November and December to 20.4° C in March. The diurnal range can reach over 30° C in the dry season. Frosts are generally absent year round. Mean annual rainfall is 960 mm, over 70 percent of which falls between March and October.
- Alemaya, located 520 km east of Addis Ababa, near the Somali-Djibouti border, has an elevation of about 1,800 masl. Production is geared to export, primarily to Djibouti. The area lies at the transition between the Quolla and Waina Dega zones. Soils, developed on granites, limestone, and sandstone, are similar in color, structure, and topographic distribution to those described for Holetta above. The deepest, most fertile soils are located in valley bottoms, but are subject to waterlogging. This area has also suffered recurrent drought.
PRODUCTION SYSTEMS AND CONSTRAINTS
The Agricultural Calendar
Given the great diversity of Ethiopia's agroecology, the agricultural calendar is regionally variable. Potatoes are generally planted to correspond to the peak of the meher long rains. In frost-free areas, another crop might be planted several months later to utilize the end of meher rains and any residual moisture. Where irrigation is feasible, an additional crop can be planted in February or March, usually past the danger of frost in most of Ethiopia (Borgel et. al. 1980). Where late blight has become a serious constraint to potato production, some farmers have shifted production to the belg season, especially where irrigation is available (Medhin et. al. 2001). Dates of harvest vary according to weather, farmers' preferences, varieties used, and the availability of labor (Borgel et. al. 1980).
Potatoes are usually grown in Ethiopia in a multicropping or rotational system, typical of Ethiopian agriculture in general. In many areas of Ethiopia, the leading crop is teff (Erogrostis teff), a grain unique to this region of the world. Teff cultivation requires several plowings for fine seedbed preparation, which can contribute to soil erosion, a factor which favors crop rotation and multicropping to maintain soil productivity (Desta et. al. 2000). At mid altitudes (1,800 - 2,000 masl), potatoes alternate with cereals such as wheat or barley. Many farmers plant cereals, including maize, in the short rains, followed by potatoes or cereals (typically wheat or barley) in the long rains (Medhin et. al. 2001).
In the Amhara region, major planting begins in March to May, and most harvesting takes place from July to October. Potatoes are often grown in rotation with other crops such as maize, linseed, rapeseed, faba beans, or haricot beans following the last cultivation of potato in May or June. A 1997 survey of 420 farmers in the Amhara region indicated that about half intercropped potatoes with other crops. Factors affecting their decisions included late blight pressure, market outlets, seed availability, competition with other growers, and periodic food shortages (Medhin et. al. 2001).
Land Preparation and Weeding
Plowing, disking, and ridging must be done before the start of the rainy season, generally one or two months before planting. In the areas for which information is available, most of this work is done by hand or with oxen. Preparation of previously uncultivated land is usually done by hand. Generally, fields are plowed two to five times followed by disking and hilling or ridging (Borgel et. al. 1980).
Weed control is mainly through cultivation, typically with hoes and similar implements. In the three areas studied by Borgel et. al. (1980), farmers generally weeded twice per season: once when the plants reach ten to twelve centimeters (cm) and a second time about a month later. Around Alemaya some farmers perform the second weeding at flowering. Mounding of soil (often called "hilling") is usually done concurrently with weeding.
Selection and Preparation of Seed Tubers
Whole tubers are generally preferred to cut tubers because of the higher rotting susceptibility and the spread of disease which can be caused by cutting. When cutting is practiced, pieces are treated by exposure to the air and dusting with ashes prior to planting. The use of chemicals to prevent disease or to encourage early sprouting is rare to non-existent. The importance of early sprouting is widely recognized, and the most common means to break dormancy is achieved by covering the tubers to raise temperature. Such methods typically isolate the tubers from light, and the resulting sprouts are often weak and pale. Seed is applied at rates of between 800 and 1,100 kilograms per hectare. Spacing varies according to the variety used, the environmental conditions, the season, and farmers' preferences (Borgel et. al. 1980).
Fertility Management
Borgel et. al. (1980) reported that commercial fertilizers were widely used in all three of their study areas (Holetta, Awassa, and Alemaya), although more recent studies indicate that fertilizer is not widely used. The government was subsidizing fertilizer until 1994, when subsidies were withdrawn as part of a market liberalization program. Prices are temporally and regionally variable, but in general, grain prices, declining soil fertility, and drought risk have made the net benefits of commercial fertilizer marginal, even when it is available (Gebeyehu et. al. 2002). Desta et. al. (2000) reported that in the Amhara Region, the consumption of commercial fertilizer was gradually increasing, due in part to a new agricultural extension system initiated in 1997, but was still limited to approximately 25-35 percent of smallholder farmers. Higher consumption is constrained by untimely supply, limited infrastructure (especially in remote areas), and fertilizer prices increasing relative to crop prices. Farmers apply animal manure to crops when it is available.
Irrigation
There is strong potential for further development of irrigation in Ethiopia given the nation's endowment of several large river basins. Most schemes remain traditional small-scale projects, and the yield of irrigated crops is estimated at only 1.4 times that of rainfed crops, suggesting potential for improvement (Desta et. al. 2000).
Major crops under irrigation include maize, sorghum, and vegetables (probably including potatoes within a larger category). The irrigated dry season potato crop can be very important because late blight is less severe during the dry season, and the limited availability of irrigation water results in a seasonal shortage of potatoes and other crops, and correspondingly high prices (Borgel et. al. 1980). Potato cultivation during this season also allows for the possibility of farmers being self-sufficient in production of seed tubers.
Harvesting
Determining when to harvest is based on the drying of foliage, the vegetative cycle of the varieties planted, and observations of tubers. Harvesting is usually done manually to avoid damage to tubers. Potatoes for market are harvested all at once while potatoes for home consumption are harvested as needed. Some farmers reportedly harvest their consumption potatoes over a period as long as three months. Some tubers are inevitably missed and left in the ground where they act as vectors for disease and pests and compete with subsequent crops as weeds (Borgel et. al. 1980).
Disease and Pest Constraints
This list is far from complete, but includes diseases and pests known to be serious constraints to potato cultivation in Ethiopia. For more technically specific information (though not usually specific to Ethiopia), please refer to the relevant sites included in:
Late Blight (LB) (Phytophthora infestans) is probably the most significant disease constraint of potatoes across the major production areas of Ethiopia.
- For more information, please see, from the Global Initiative on Late Blight (GILB) Ethiopia Profile.
Bacterial Wilt (Pseudomonas solanacearum) can be a severe production constraint of potato and other solanaceous crops such as tomato and eggplant, especially in warmer weather occurring at lower altitudes in Ethiopia. Kassa and Lemaga (1993) reported that limited research had been done on the development of potato cultivars resistant to bacterial wilt, but that several varieties of the "BR" series demonstrated some degree of resistance.
Tuber Moth (Phthorimaea operculella Zeller) can be a major pest of potatoes either in fields or storage, potentially a cause of total crop loss in the form of discards or unfitness of tubers for seed. Farmers also suffer losses of reduced prices for damaged potatoes, or indirectly when they are forced to sell potatoes at low prices to avoid damage (Silseshi and Teriessa 2001). Infestation can be minimized by planting seed tubers deeply and by keeping tubers covered, especially during longer periods of in situ storage. A few varieties, such as CIP 378378-2 and AI-624-21, have demonstrated some resistance to tuber moth infestation.
VARIETIES AND SEED SYSTEMS
Varieties
Given the great diversity of Ethiopia, it is not surprising that there are no "standard" varieties grown widely throughout the country. Since names in any of several regional languages can be inspired by many circumstances or qualities (such as the place from which a variety was locally introduced or a descriptive quality of the tuber), it is very difficult to know if various names refer to the same or different genotypes. Medhin et. al. (2001) list 33 major varieties grown in Ethiopia, including several recently introduced from international research institutions, but this does not claim to be a comprehensive list.
Local varieties are reported to be generally low yielding, susceptible to diseases and pests, and subject to rapid virus degeneration (Kidane-Mariam 1980; Lemaga 1982). However, farmers apparently consider many factors in selecting varieties. In addition to the essential qualities of yield and resistance to disease (especially late blight), varieties are also selected for tuber traits considered positive, especially for commercial sale: relative smoothness of texture, shallow eyes, more attractively shaped (specifics not provided), whiter color in preference to red, and cooking quality (Borgel et. al. 1980; Medhin et. al. 2001).
In addition to varieties which have existed for many years in Ethiopia and others more recently introduced via research institutions selected for specific traits, non-government organizations (NGO's) have responded to acute famine in Ethiopia by importing potato seed. The mid 1980s drought resulted in the importation of more than 2,340 tons of potato seed of seven varieties from Europe: Cara, Spunta, Diamond, Cardinal, Barka, Ajax, and Alpha. Of these varieties, only Cara is reported still in production in some semi-arid and lowland areas. The others have been completely eliminated by late blight (Medhin et. al. 2001).
Seed Systems
Borgel et. al. reported in 1980 that very little imported or certified seed is available to farmers; the main seed sources were local markets and previous harvests. Over twenty years later, Medhin et. al. (2001) reported, "There has not been any institution in Ethiopia that multiplies and distributes potato seed tubers. Thus, farmers are forced to use inferior-sized tubers from their own harvest, and this practice has contributed to the build-up of diseases, which causes low yield." Sources of seed for other crops have developed in recent years, for example the state-owned Ethiopian Seed Enterprise and the privately owned Pioneer Seed Company. The World Bank and other organizations have also developed programs to work with farmers to multiply seed on a contract basis, but apparently not yet including potato (Desta 2000).
The means by which farmers obtain seed tubers are complex and, characteristic of Ethiopia, regionally variable. In areas free of frost and where farmers have access to irrigation, they can usually maintain production over a sufficient duration of the year to be self-sufficient in seed tubers, and perhaps (roads and other infrastructure permitting) sell seed to other areas. Demand for seed is very high in June, when supplies are limited (Borgel et. al. 1980). In areas of higher altitude, especially the Central Highlands, farmers typically have to rely on seed tubers purchased from other regions with growing seasons complementary to their own (Medhin et. al. 2001). Lack of available seed can be a major factor in determining whether farmers continue to grow potatoes, or to rely only on cereals. Although the government sometimes declares quarantines of areas where disease has been known to occur, lack of effective enforcement allows the internal market of seed tubers to become a source of further distribution of disease.
Measures to increase the availability of high-quality seed have included several options, such as:
- Certified seed programs managed by government farms;
- Multiplication and marketing by farmers under some supervision and certification procedures;
- A less formal farmer-to-farmer approach.
Asamenew and Bahru (2000) have reported that on-farm seed production trials and subsequent seed tuber distribution undertaken by farmers under the direction of the Ethiopian Agricultural Research Organization (EARO) in the southeastern highlands have been successful both in demonstrating the potential for the informal farmer-to-farmer approach to distribution of higher quality seed tubers, and for the dissemination of improved production technologies, albeit with "carefully selected farmers." Two varieties, Menagesha and Awash, were especially high yielding compared to a local variety which succumbed to late blight. This area, however, is one where irrigation is available, hence where farmers are more readily self-sufficient in seed tubers. The authors conclude that on-farm seed potato production with a farmer participatory approach remains the best option for improved seed distribution, at least until other institutions are established to assume this role.
Self-Help Development International (SHDI), an NGO with several years of experience in Ethiopia, took a similar approach with farmers to multiply seed of improved varieties which had been distributed on loan. After repayment of the loan in kind, participant farmers could sell any additional seed back to SHDI or at local markets. The project provided further support for farmer-to-farmer seed distribution, but again in an area where irrigation makes off-season production feasible (Getachew and Mela 2000).
Some research has been undertaken on the use of true potato seed (TPS) as a means to produce planting material which addresses some of the constraints noted above. TPS is cheap and easy to store and transport, and has the potential to produce healthier first generation tubers, free of the buildup of viral disease which typically occurs from small and inferior seed tubers kept from previous harvests. Disadvantages typical of TPS, such as lack of uniformity and small first generation tubers, can be mitigated through careful selection of appropriate genotypes, via either open-pollinated or hybrid breeding techniques. Hybrid production has demonstrated some advantages, though not necessarily enough to justify its higher cost. Initial experiments indicate that the greatest potential for TPS in Ethiopia might be during the off season ([i.e_] not during the long rains), when late blight pressure is relatively low (Lemaga _et. al. 1995). (More information about TPS is available via Potato Info Links, Varieties and Seed Systems.)
CONSUMPTION, STORAGE, AND MARKETING
Consumption
Since there is very little import or export of potato in Ethiopia, consumption could be approximated by production. However, absent reliable production data, average potato consumption is likewise speculative. The most comprehensive recent survey, undertaken by the Ethiopia Agricultural Research Organization (EARO) in 2000, estimated total national production at just under 1,500,000 tons. For a population estimated at just under 65,000,000 the same year, average per capita consumption would be around 17.5 kilograms, but with strong local variation as indicated by the distribution map. This would be a moderate per capita rate by world standards, with strong potential to increase.
Storage
Borgel et. al. (1980) reported that storage of both seed and ware potatoes is problematic for most farmers, as storage losses can reach fifty percent, sometimes higher. The storage methods typically used by Ethiopian farmers apparently have not changed significantly since that time.
Medhin et. al. (2001) describe the storage methods most commonly used:
- On the floor (_[wole.l_]) up to three months with minimal losses in that time in highlands areas;
- Bed (kot/alga), wooden beds used to keep potatoes for seed, sometimes covered with straw to promote sprouting;
- Granary (_gotta/[kef.o_]) rarely practiced, usually small structures of mud walls covered in straw.
Diffused Light Stores (DLS), developed by CIP, have proven a capacity to maintain the quality of seed tubers, especially in the Central Highlands region (Medhin et. al. 2001). The use of DLS has been strongly encouraged by projects which work with farmers to multiply seed tubers, enabling them to keep their seed longer and thus reduce their dependency on other sources (Getachew and Mela 2000). However, in spite of apparent success in experimental treatments, the DLS technique remains very rare.
Marketing
Even during the Dergue regime, when the Ethiopian Government was more actively involved in agricultural production and distribution of crops, potato marketing remained an essentially free market activity, but one in which farmers were challenged by lack of transportation and timely and accurate market information. Decades later, farmers still face essentially the same situation. Wholesale prices at times of peak supply can drop to as little as US$10 per ton. When supplies become excessive, farmers in more remote locations facing high transport costs might be forced to dump their potatoes (Medhin et. al. 2001).
"Founded in June 1997...the Ethiopia Agricultural Research Organization (EARO) is the highest autonomous government body and the largest specialized agency to co-ordinate the agricultural research activities in the country. EARO is primarily responsible for generating, improving and adapting technologies and coordinating, encouraging and assisting research activities in order to fulfill the current and long term agricultural requirements of the country."
Information regarding research and educational institutions in Ethiopia is also available via the International Food Policy Research Institute (IFPRI) Agricultural Science and Technology Indicators ASTI for Ethiopia.
The Regional Potato and Sweetpotato Improvement Network in Eastern and Central Afriica (PRAPACE) developed out of PRAPAC, a network established in 1982 by the national research institutions of Burundi, Rwanda and the Democratic Republic of Congo to coordinate their potato programs. PRAPACE currently collaborates with potato and sweetpotato programs of ten countries (Burundi, Democratic Republic of Congo, Eritrea, Ethiopia, Kenya, Madagascar, Rwanda, Sudan, Tanzania and Uganda), all members of the Association for Strengthening Agricultural Research in Eastern and Central Africa (ASARECA). The International Potato Center (CIP) provides support in the forms of improved germplasm, scientific information, training, and administrative assistance. The United States Agency for International Development (USAID) funds the network.
The Famine Early Warning System (FEWS), also supported by USAID, sponsors FEWSNET, which features reports of climate and food security status by region of several countries of Africa, including Ethiopia.
CONTRIBUTORS
Kelly Theisen is the principal contributor to the revised (2006) Ethiopia potato chapter, some sections based on the previous edition by [R.E] Rhoades, [R.J] Hijmans, and L. Huaccho.
Charles Crissman provided information and advice via personal communication.
REFERENCES
Albert, W. 1984. Consultancy Report of the Possibilities for Application of Small-scale Potato Storage Techniques in Developing Countries. FAO. Rome.
Asamenew, T. and Z. Bahru. Transfer of Improved Potato Varieties and Production Technologies in the Southeastern Highlands of Ethiopia. African Potato Association Conference Proceedings, Vol. 5, pp. 153-156.
Belete, A.; [J.L] Dillon; [F.M] Anderson. 1991. Development of Agriculture in Ethiopia since the 1975 Land Reform. Agricultural Economics (Netherlands) (6):159-175
Borgel, H., et. al. 1980. Production, Marketing and Consumption of Potatoes in the Ethiopian Highlands (Holetta, Awassa, Alemaya). Centre for Advanced Training in Agricultural Development, Institute of Socio-Economics of Agricultural Development, Technical University of Berlin.
Desta, Lakew; M. Kassie; S. Benin; J. Pender. 2000. Land Degradation and Strategies for Sustainable Development in the Ethiopian Highlands: Amhara Region. International Livestock Research Institute Socio-Economics and Policy Research Working Paper 32. Nairobi, Kenya.
FAOSTAT (Agriculture/ Agricultural Production/ Crops Primary)
Gebeyehu, S.; K. Muminjanov; A. Mwilala; K. Rijal; S. Subramaniam; L. Weili. 2002. Food Security in a Bread Basket: Food Security Among Households in the Different Agro-Ecological Zones in Arsi Negele Woreda, Ethiopia. International Centre for Development-Oriented Research in Agriculture (ICRA) and Ethiopian Agricultural Research Organization (EARO). Working Document Series 100. Wageningen, The Netherlands and Nazareth, Ethiopia.
Getachew, Tesfaye and Awole Mela. 2000. The Role of SHDI in Potato Seed Production in Ethiopia: Experience from Alemaya Integrated Rural Development Project. African Potato Association Conference Proceedings, Vol. 5, pp. 109-112.
Grepperud, Sverre. 1996. Population Pressure and Land Degradation: The Case of Ethiopia. Journal of Environmental Economics and Management 30:18-33.
Kassa, Bekele and Berga Lemaga. 1993. Research on Bacterial Wilt of Potato in Ethiopia. In: PRAPACE Workshop on Bacterial Wilt of Potato Caused by Pseudomonas Solanacearum. Bujumbura, Burundi. February 22-26, 1993, pp. 11-20.
Kidane-Mariam, [H.M] 1980. Project Proposal for the Development of an Ethiopian Potato Program. Addis Ababa. Manuscript.
Laufer, B. 1938. The American Plant Migration. Part I: The Potato Archeology Series. Field Museum of National History. Vol 28, Number I. Publication 418. Chicago.
Lemaga, Berga. 1983. Country Program Report on Ethiopian Potato Research Activities. Presented at the Regional Workshop on Potato Development and Transfer of Technologies in Tropical Africa, Addis Ababa, Ethiopia, August 22-September 1, 1982.
Lemaga, Berga; Endale Gebre; Bekele Kassa. 1995. True Potato Seed Research in Ethiopia and Future Trends. In: Hardy, B.; Malagamba, P.; Martin, C. (eds.). True Potato Seed in the Middle East and Africa: Proceedings of an International Workshop, pp. 9-15. Cairo.
Medhin, G.; W. Giorgis; Endale Gebre; Kiflu Bedane; Bekele Kassa. 2001. Country Profile on Potato Production and Utilization: Ethiopia. Ethiopian Agricultural Research Organization (EARO), Holetta Agricultural Research Centre, National Potato Research Program.
Medhin, G.; W. Giorgis; Bekele Kassa; Endale Gebre; Atsed E. Solomon; Berga Lemaga; Ramzy El-Bedewy; Agaje Tesfaye. Farmer Based Potato Seed Tuber Production(1998-2000). Final Report. PRAPACE (Regional Potato and Sweetpotato Improvement Network in Eastern and Central Africa).
Onke, Ayole. 1984. Current Potato Development in Ethiopia. Country Report Presented at the Regional Potato Post-Harvest Workshop, June 18-22. Nairobi, Kenya.
Sileshi, G. and J. Teriessa. 2001. Tuber Damage by Potato Tuber Moth, Phthorimaea operculella Zeller (Lepidoptera:Gelechiidae) in the Field in Eastern Ethiopia. International Journal of Pest Management (UK). 47(2): 109-113.
Wolfe, [W.J] 1988. Ideology, Administration, and Development in Modern Ethiopia. International Development Institute, Indiana University, Bloomington, Indiana.
Yilma, S. 1991. The Potentials of True Potato Seed in Potato Production in Ethiopia. Actae Horticultrae 270: 389-394.