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An Assessment of Pest Damage on Grain Sorghum in Botswana

Published online by Cambridge University Press:  03 October 2008

K. E. Flattery
Affiliation:
Agricultural Research Station, Private Bag 0033, Gaborone, Botswana

Summary

In trials conducted over five years, data on pest (insect, disease, bird) attack and yield of sorghum cultivar 65D were accumulated. A modified analytical method of damage assessment is described, which includes consideration of all pest occurrences and different levels and timing of pest attack. There was a positive correlation between crop yield and rainfall. The selective infestation of stronger plants, or the ability of those plants to support pest populations, is shown; thus, in most cases, yield reductions are masked. The importance of the tillering habit of 65D on yield, and its ability to compensate for pest damage by further tillering, are shown. A cultivar which does not normally tiller was tested in the final year. Effects on yield of all the pests encountered in the five years are discussed.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1982

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References

REFERENCES

Anon. (1974). Dryland Crop Production in Botswana. A Review of Research, 1969–74. Gaborone, Botswana: Ministry of Agriculture.Google Scholar
Davies, J. C. & Sheshu, K. V. Reddy (1977). Insect Pests of Sorghum and Pearl Millet and Assessment of Insect Numbers and Losses. ICRISAT Miscellaneous Publication, Hyderabad, India.Google Scholar
Doggett, H. (1970). Sorghum. London: Longmans Green.Google Scholar
Harvey, W. R. (1975). Least Squares Analysis of Data with Unequal Subclass Numbers. USDA Publication, ARS H4.Google Scholar
Judenko, E. (1973). Analytical Method for Assessing Yield Losses Caused by Pests on Cereal Crops with and without Pesticides. COPR Tropical Pest Bulletin 2.Google Scholar
Le Clerg, E. L. (1971). Field experiments for assessment of crop losses. In FAO Manual Crop Loss Assessment Methods (Ed. Chiarappa, L.). London: CAB.Google Scholar
Vanderlip, R. L. & Reeves, H. E. (1972). How a sorghum plant develops. Agronomy Journal 64:1316.CrossRefGoogle Scholar
Van Rensburg, N. J. & VanHamburg, H. Hamburg, H. (1975). Grain sorghum pests: an integrated control approach. Proceedings of the First Congress of the Entomological Society of South Africa 152162.Google Scholar
Wilson, A. G. L. (1976). Varietal responses of grain sorghum to infestation by Helio this armigera. Experimental Agriculture 12:257265.CrossRefGoogle Scholar