Journal of Chemical Ecology

, Volume 28, Issue 9, pp 1871–1885 | Cite as

Control of Witchweed Striga hermonthica by Intercropping with Desmodium spp., and the Mechanism Defined as Allelopathic

  • Zeyaur R. Khan
  • Ahmed Hassanali
  • William Overholt
  • Tsanuo M. Khamis
  • Antony M. Hooper
  • John A. Pickett
  • Lester J. Wadhams
  • Christine M. Woodcock

Abstract

During investigations into the control of insect damage to maize crops in subsistence farming in Kenya, which involved intercropping with repellent plants, the fodder legumes silverleaf (Desmodium uncinatum) and greenleaf (D. intortum) were also found to reduce dramatically the infestation of maize by parasitic witchweeds such as Striga hermonthica. This effect was confirmed by further field testing and shown to be significantly greater than that observed with other legumes, e.g., cowpea, as were the concomitant yield increases. The mechanism was investigated, and although soil shading and addition of nitrogen fertilizer showed some benefits against S. hermonthica infestation, a putative allelopathic mechanism for D. uncinatum was observed. In screenhouse studies, a highly significant reduction in S. hermonthica infestation was obtained when an aqueous solution, eluting from pots in which D. uncinatum plants were growing, was used to irrigate pots of maize planted in soil seeded with high levels of S. hermonthica. Growth of the parasitic weed was almost completely suppressed, whereas extensive infestation occurred with the control eluate. Laboratory investigations into the allelopathic effect of D. uncinatum, using samples of water-soluble chemical components exuded from cleaned roots, demonstrated that this involved a germination stimulant for S. hermonthica and also an inhibitor for haustorial development.

Allelopathy maize Striga Desmodium nitrogen shading silverleaf germination stimulant suicidal germination 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

REFERENCES

  1. Baily, R. A. 1984. Quasi-complete Latin square: construction and randomization. J. Res. Statist. Soc. B 46:323–334.Google Scholar
  2. Berner, D. K., Kling, J. G., and Singh, B. B. 1995. Striga research and control: A perspective from Africa. Plant Dis. 79:652–660.Google Scholar
  3. Berner, D., Carsky, R., Dashiell, K., Kling, J., and Manyong, V. 1996. A land management based approach to integrated Striga hermonthica control in sub-Saharan Africa. Outlook Agric 25:157–164.Google Scholar
  4. Carson, A.G. 1986. Effect of intercropping sorghum and groundnuts on density of Striga hermonthica in Gambia. Trop. Pest Manage. 35:130–132.Google Scholar
  5. Carson, A. G. 1989. Research and development strategies for the control of Striga hermonthica in the Gambia, pp. 101–118, in T. O. Tobson and H. R. Broad (eds.). Striga–Improved Management in Africa. Proceedings of the FAO/OAU All-African Government Consultation on Striga control, October 20-24, 1988, Maroua, Cameroon.Google Scholar
  6. Eplee, R. E. and Norris, R. S. 1990. Soil sampling collection equipment and equipment to separate seeds from soil, pp. 136–140, in P. E. Sand, R. E. Eplee, and R. G. Westbrooks (eds.). Witchweed Research and Control in United States. Weed Science Society of America, Champaign, Illinois.Google Scholar
  7. Gressel, J. 2000. Molecular biology of weed control. Transgenic Res. 9:355–382.Google Scholar
  8. Khan, Z. R., Ampong-Nyarko, K., Chiliswa, P., Hassanali, A., Kimani, S., Lwande, W., Overholt, W. A., Pickett, J. A., Smart, L. E., Wadhams, L. J., and Woodcock, C. M. 1997. Intercropping increases parasitism of pests. Nature 388:631–632.Google Scholar
  9. Khan, Z. R., Pickett, J. A., Van Den Berg, J., Wadhams, L. J., and Woodcock, C. M. 2000. Exploiting chemical ecology and species diversity: stem borer and striga control for maize and sorghum in Africa. Pest Manage. Sci. 56:957–962.Google Scholar
  10. Lagoke, S. T. O., Parkinson, V., and Agunbiade, R.M. 1991. Parasitic weeds and control methods in Africa; pp. 3–14, in S.K. Kim(ed.). Combating Striga in Africa. InternationalTropical Agriculture, Proceedings, International Workshop organized by IITA, ICRISAT and IDRC, August 22-24, 1988, IITA, Ibadan, Nigeria.Google Scholar
  11. M'Boob, S. S. 1989. A regional programme for West and Central Africa, pp. 190–194, in T. O. Tobson, and H. R. Broad (eds.), Striga–Improved Management in Africa. Proceedings of the FAO/OAUAll-AfricanGovernment Consultation on Striga control. October 20-24, 1988, Maroua, Cameroon.Google Scholar
  12. Mumera, L. M. and Below, F. E. 1993. Crop ecology, production and management. Crop Sci. 33:758–763.Google Scholar
  13. Musselman, L. J. 1994. Striga sp., in R. Labrada, J. C. Caseley and C. Parker (eds.). Weed Management for Developing Countries. FAO Plant Production and Protection Paper 120, Food and Agriculture Organization of the United Nations, Rome, 381 pp.Google Scholar
  14. Musselman, L. J., Bhrathalakshmi, Safa, S. B., Knepper, D. A., Mohamed, K. I., and White, C. L. 1991. Recent research on biology of Striga asiatica, S. gesnerioides and S. hermonthica, pp. 31–41, in S. K. Kim (ed.). Combating Striga in Africa. Proceedings, International Workshop organised by IITA, ICRISAT and IDRC, August 22-24, 1988, IITA, Ibadan, Nigeria.Google Scholar
  15. Netzly, D. H., Riopel, J. L., Ejeta, G., and Butler, L.G. 1988. Germination stimulants of witchweed (Striga asiatica) from hydrophobic root exudate of sorghum (Sorghum bicolor). Weed Sci. 36: 441–446.Google Scholar
  16. Oswald, A., Ransom, J. K., Kroschel, J, and Sauerborn, J. 1999. Suppression of Striga on maize with intercrops, pp. 168–171, in CIMMYT and EARO (eds.). Maize Production Technology for the Future: Challenges and Opportunities. Sixth Eastern and Southern African Regional Maize Conference, September 21-25, 1998, Addis Ababa, Ethiopia.Google Scholar
  17. Parker, C. and Riches, C. R. 1993. Parasitic Plants of the World: Biology and Control. CAB International, Wallingford, United Kingdom.Google Scholar
  18. Press, M. and Gurney, A. 2000. Plant eats plant. Biologist 47:189–193.Google Scholar
  19. SAS INSTITUTE. 1996. SAS/ STAT Software: Change and enhancement through release 6.11. SAS Institute, Cary, North Carolina.Google Scholar
  20. Shugar, G. J., Shugar, R. A., Bauman, L., and Bauman, R. S. 1981. Chemical Technicians’ Ready Reference Handbook, 2 ed. McGraw-Hill, New York.Google Scholar
  21. Smart, L. E., Blight, M. M., Pickett, J. A., and Pye B. J. 1994. Development of field strategies incorporating semiochemicals for control of the pea and bean weevil, Sitona lineatus L. Crop Prot. 13:127–135.Google Scholar
  22. Sugimoto, Y., Wigchert, C. M., Thuring, J. W. J. F., and Zwaneburg, B. 1998. Synthesis of all eight stereoisomers of the germination stimulant sorgolactone. J. Org. Chem. 63:1259–1267.Google Scholar
  23. Welzel, P., Rohrig, S., and Milkova, Z. 1999. Strigol-type germination stimulants: the C-2’ configuration problem. Chem. Commun. 1999:2017–2022.Google Scholar
  24. Wigchert, S. C. M., Kuiper, E., Boelhouwer, G.J., Nefkens, G. H. L., Verkleij, J. A. C., and Zwanenburg, B. 1999. Dose-response of seeds of the parasitic weeds Striga and Orobanche toward the synthetic germination stimulants GR 24 and Nijmegen 1. J. Agric. Food Chem. 47:1705–1710.Google Scholar

Copyright information

© Plenum Publishing Corporation 2002

Authors and Affiliations

  • Zeyaur R. Khan
    • 1
  • Ahmed Hassanali
    • 2
  • William Overholt
    • 2
  • Tsanuo M. Khamis
    • 3
  • Antony M. Hooper
    • 4
  • John A. Pickett
    • 4
  • Lester J. Wadhams
    • 4
  • Christine M. Woodcock
    • 4
  1. 1.The International Centre of Insect Physiology and EcologyMbita Point Field StationMbita, S. NyanzaKenya
  2. 2.The International Centre of Insect Physiology and EcologyNairobiKenya
  3. 3.Chemistry DepartmentJomo Kenyatta University of Agriculture and TechnologyNairobiKenya
  4. 4.Biological and Ecological Chemistry DepartmentIACR-RothamstedHarpenden, HertfordshireUnited Kingdom

Personalised recommendations