Advertisement

The current pandemic of cassava mosaic virus disease in Uganda

  • G. W. Otim-Nape
  • J. M. Thresh

Abstract

This chapter differs from many of the other contributions to this volume in that it deals with one specific disease. Cassava mosaic virus disease (CMD) justifies special treatment for several reasons:
  • Cassava provides one of the main staple foods in many tropical areas and it is particularly important in many of the poorest countries of sub-Saharan Africa.

  • CMD is the most important disease of cassava in Africa and also in Sri Lanka and southern India.

  • The disease has a long history in Africa, where research has been in progress for many years. Indeed, CMD is likely to have received more attention than any other vector-borne disease of an African food crop.

  • CMD is a prime example of a particularly important group of virus diseases of tropical, subtropical and temperate crops — those which have a dual strategy of dispersal in that they are disseminated in vegetative propagules and transmitted by an arthropod vector.

  • A very damaging pandemic of CMD currently causes serious food shortages and affects the livelihood and well-being of rural communities in many parts of Uganda and threatens adjacent areas of Kenya and Tanzania.

  • When attempts were made to control the pandemic, it became apparent that there was insufficient information to initiate effective management strategies and this led to increased research on CMD, not only in Uganda but elsewhere in Africa.

  • The pandemic provides a striking example of the way in which the occurrence and control of a disease is closely associated with the vulnerability of the varieties being grown.

  • Experience with CMD in Uganda has demonstrated the advantages of adopting an ecological approach in seeking to explain the main features of the current pandemic and its effects on the amount and type of cassava grown.

  • Research on the disease and the viruses responsible has benefited greatly from collaboration between virologists in the tropics and those in developed countries of Europe and North America with access to sophisticated laboratory equipment.

Keywords

Tuberous Root Infected Cutting Cassava Mosaic Disease Cassava Production African Cassava Mosaic Virus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Anon. (1993) How Akwa Thom overcame a crisis in cassava production. Cassava Newsletter, 17, 9–10.Google Scholar
  2. Bock, K.R. and Woods, R.D. (1983) Etiology of African cassava mosaic disease. Plant Disease, 67, 994–995.CrossRefGoogle Scholar
  3. Bos, L. (1992) New plant virus problems in developing countries: a corollary of agricultural modernization. Advances in Virus Research, 38, 349–407.CrossRefGoogle Scholar
  4. Bua, A., Otim-Nape, G.W., Acola, G. and Baguma, Y.K. (1997) The adopted and approaches impact of cassava multiplication in Uganda, in Progress in Cassava Technology Transfer in Uganda, (eds G.W. Otim-Nape, A. Bua and J.M. Thresh), Proceedings of the National Workshop on Cassava Multiplication, Masindi 9–12 January 1996, NARO/Gatsby/NRI Publication.Google Scholar
  5. Buddenhagen, I.W. (1977) Resistance and vulnerability of tropical crops in relation to their evolution and breeding. Annals New York Academy of Sciences, 287, 309–326.CrossRefGoogle Scholar
  6. Carter, S.E., Fresco, L.O., Jones P.G. and Fairbairn, J.N. (1992) An Atlas of Cassava in Africa: Historical, Agroecological and Demographic Aspects of Crop Distribution, Centro Internacional de Agricultura Tropical, Cali, Colombia.Google Scholar
  7. Cours, G. (1951) Le manioc à Madagascar. Mémoires de l’Institut Scientifique de Madagascar, Série B3, Biologie Végétale, 203–400.Google Scholar
  8. Cours, G., Fargette, D., Otim-Nape, G.W. and Thresh, J.M. (1997) The epidemic of cassava mosaic virus disease in Madagascar in the 1930s-1940s: lessons for the current situation in Uganda. Tropical Science, 37, 1–7.Google Scholar
  9. Day, P.R. (ed.) (1977) The Genetic Basis of Epidemics in Agriculture. Annals of the New York Academy of Sciences, 287, 1–386.Google Scholar
  10. Deng, D., Otim-Nape, G.W., Sangare, A. et al. (1997) Presence of a new virus closely related to East African cassava mosaic geminivirus associated with cassava mosaic outbreak in Uganda. African Journal of Root and Tuber Crops, 2, 23–28.Google Scholar
  11. Ewald, P.W. (1983) Host—parasite relations, vectors and the evolution of disease severity. Annual Review of Ecology and Systematics, 14, 465–485.CrossRefGoogle Scholar
  12. FAO (1995) The Food and Agricultural Organization of the United Nations. Production Year Book: 1994,48 93–94. Rome.Google Scholar
  13. Fargette, D. and Vié, K. (1995) Simulation of the effects of host resistance, reversion, and cutting selection on incidence of African cassava mosaic virus and yield losses in cassava. Phytopathology, 85, 370–375.CrossRefGoogle Scholar
  14. Fargette, D., Thouvenel, J.-C. and Fauquet, C. (1987) Virus content of leaves of cassava infected by African cassava mosaic virus. Annals of Applied Biology, 110, 65–73.CrossRefGoogle Scholar
  15. Fargette, D. Thresh, J.M. and Otim-Nape, G.W. (1994) The epidemiology of African cassava mosaic geminivirus: reversion and the concept of equilibrium. Tropical Science,34 123–133.Google Scholar
  16. Fauquet, C. and Fargette, D. (eds) (1988) Proceedings: The International Seminar on African Cassava Mosaic Disease and its Control, Yamoussoukro, Côte d’Ivoire, 4–8 May 1987, C TA /FAO/ORSTOM/II TA/IAPC.Google Scholar
  17. Fauquet, C. and Fargette, D. (1990) African cassava mosaic virus: etiology, epidemiology and control. Plant Disease, 74, 404–411.CrossRefGoogle Scholar
  18. Gäumann, E. (1946) Pflanzliche Infektionslehre, Birkhäuser, Basel, 611 pp.Google Scholar
  19. Geddes, A.M.W. (1990) The Relative Importance of Crop Pests in Sub-Saharan Africa, Bulletin No. 36, Natural Resources Institute, Chatham, UK.Google Scholar
  20. Gerling, D. and Meyer, R.T. (eds) (1996) Bemisia 1995: Taxonomy, Biology, Damage, Control and Management, Intercept Publishers, Andover, UK, 702 pp.Google Scholar
  21. Gibson, R.W., Legg, J.P. and Otim-Nape, G.W. (1996) Unusually severe symptoms are a characteristic of the current epidemic of mosaic virus disease of cassava in Uganda. Annals of Applied Biology, 128, 479–490.CrossRefGoogle Scholar
  22. Harrison, B.D., Swanson, M.M. and Robinson, D.J. (1995) Cassava viruses in the Old World, in Proceedings: Second International Scientific Meeting of the Cassava Biotechnology Network, Bogor, Indonesia, 22–26 August 1994, Working Document No. 150, pp. 463–472, CBN/CRIFC/AARD/CIAT.Google Scholar
  23. Harrison, B.D., Liu, Y.L., Zhou, X. et al. (1997) Properties, differentiation and geographical distribution of geminiviruses that cause cassava mosaic disease. African Journal of Root and Tuber Crops, 2, 19–22.Google Scholar
  24. Hengeveld, R. (1989) Dynamics of Biological Invasions, Chapman & Hall, London, 160 pp. Holt, J., Jeger, M.J., Thresh, J.M. and Otim-Nape, G.W. (1997) An epidemiological model incorporating vector population dynamics applied to African cassava mosaic virus disease. Journal of Applied Ecology, 34, 793–806.Google Scholar
  25. Jameson, J.D. (1964) Cassava mosaic disease in Uganda. East African Agricultural and Forestry Journal, 29, 208–213.Google Scholar
  26. Jennings, D.L. (1994) Breeding for resistance to African cassava mosaic geminivirus in East Africa. Tropical Agriculture, 34, 110–122.Google Scholar
  27. Jones, W.O. (1969) Manioc in Africa,Stanford University Press, Stanford, California. Kornberg, H. and Williamson, M.H. (eds) (1987) Quantitative Aspects of the Ecology of Biological Invasions,Transactions of the Royal Society of London, 240 pp.Google Scholar
  28. Legg, J.P. and Ogwal, S. (1998) Changes in the incidence of African cassava mosaic disease and the abundance of its whitefly vector along south—north transects in Uganda. Journal of Applied Entomology,(in press).Google Scholar
  29. Legg, J.P., Gibson, R.W. and Otim-Nape, G.W. (1994) Genetic polymorphism amongst Ugandan populations of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae), vector of African cassava mosaic geminivirus. Tropical Science, 34, 73–81.Google Scholar
  30. Nweke, F.I. (1994) Farm level practices relevant to cassava plant protection. African Crop Science Journal, 2, 563–582.Google Scholar
  31. Nweke, F.I., Dixon, A.G.O., Asiedu, R. and Folayan, S.A. (1994) Cassava varietal needs of farmers and the potential for production growth in Africa. Collaborative Study of Cassava in Africa: Working Paper No. 10, IITA, Ibadan, 239 pp.Google Scholar
  32. Otim-Nape, G.W. (1993) Epidemiology of the African cassava mosaic geminivirus disease (ACMD) in Uganda. PhD Thesis, University of Reading, UK, 256 pp.Google Scholar
  33. Otim-Nape, G.W., Bua, A. and Baguma, Y. (1994) Accelerating the transfer of improved production technologies: controlling African cassava mosaic virus disease epidemics in Uganda. African Journal of Crop Science, 2, 479–495.Google Scholar
  34. Otim-Nape, G.W., Thresh, J.M. and Fargette, D. (1996) Bemisia tabaci and cassava mosaic virus disease in Africa, in Bemisia 1995: Taxonomy, Biology, Damage, Control and Management, (eds D. Gerling and R.T. Meyer), Intercept Publishers, Andover, UK, pp. 319–350.Google Scholar
  35. Otim-Nape, G.W., Bua, A. and Thresh, J.M. (eds) (1997a) Progress in Cassava Technology Transfer in Uganda, Proceedings of the National Workshop on Cassava Multiplication, Masindi, 9–12 January 1996, NARO/Gatsby/NRI Publication.Google Scholar
  36. C)tim-Nape, G.W., Bua, A., Thresh, J.M. et al. (1997b) Cassava Mosaic Virus Disease in Uganda: the current pandemic and approaches to control, NRI/NARO publication, Chatham Maritime, UK, 65 pp.Google Scholar
  37. Otim-Nape, G.W., Thresh, J.M. and Shaw, M.W. (1998) The incidence and severity of cassava mosaic virus disease in Uganda: 1990–1992. Tropical Science,(in press).Google Scholar
  38. Simmonds, N.W. (1962) Variability in crop plants, its use and conservation. Biological Reviews, 37, 442–465.CrossRefGoogle Scholar
  39. Swanson, M.M. and Harrison, B.D. (1994) Properties, relationships and distribution of cassava mosaic geminiviruses. Tropical Science, 34, 15–25.Google Scholar
  40. Thresh, J.M. (1985) The origins and epidemiology of some important plant virus diseases. Applied Biology, 5, 1–65.Google Scholar
  41. Thresh, J.M. (1990) Plant virus epidemiology: the battle of the genes, in Recognition and Response in Plant Virus Interactions, (ed. R.S.S. Fraser), NATO ASI Series H, Cell Biology, 41, 93–121, Springer-Verlag, New York.CrossRefGoogle Scholar
  42. Thresh, J.M. and Otim-Nape, G.W. (1994) Strategies for controlling African cassava mosaic geminivirus. Advances in Disease Vector Research, 10, 215–236.CrossRefGoogle Scholar
  43. Thresh, J.M., Owusu, G.L.K. and Ollennu, L.A.A. (1988) Cocoa swollen shoot: an archetypal crowd disease. Journal of Plant Diseases and Protection, 95, 428 446.Google Scholar
  44. Thresh, J.M., Fargette, D. and Otim-Nape, G.W. (1994a) The viruses and virus diseases of cassava in Africa. African Crop Science Journal, 2, 459–478.Google Scholar
  45. Thresh, J.M., Otim-Nape, G.W. and Jennings, D.L. (1994b) Exploiting resistance to African cassava mosaic virus. Aspects of Applied Biology, 39, 51–60.Google Scholar
  46. Thresh, J.M., Otim-Nape, G.W., Legg, J.P. and Fargette, D. (1997) African cassava mosaic virus disease: the magnitude of the problem. African Journal of Root and Tuber Crops, 2, 13–19.Google Scholar
  47. Ullstrup, A.J. (1972) The impacts of the southern corn leaf blight epidemics of 1970–1971. Annual Review of Phytopathology, 10, 37–50.CrossRefGoogle Scholar
  48. van den Bosch, F., Zadoks, J.C. and Metz, J.A.J. (1988) Focus expansion in plant disease. 1. The constant rate of focus expansion. Phytopathology, 78, 54–58.CrossRefGoogle Scholar
  49. Zadoks, J.C. and van den Bosch, F. (1994) On the spread of plant disease; a theory on foci. Annual Review of Phytopathology, 32, 503–521.PubMedCrossRefGoogle Scholar
  50. Zhou, X., Liu, Y., Calvert, L. et al. (1997) Evidence that DNA-A of a geminivirus associated with severe cassava mosaic disease in Uganda has arisen by interspecific recombination. Journal of General Virology, 78, 2101–2111.PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 1998

Authors and Affiliations

  • G. W. Otim-Nape
  • J. M. Thresh

There are no affiliations available

Personalised recommendations