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Soil Conditions in Oviposition Sites of Zonocerus variegatus (L.) in Cassava Plots in a Sub-Humid Tropical Environment

Published online by Cambridge University Press:  19 September 2011

G. F. Tamu*
Affiliation:
Department of Zoology, University of Ibadan, Nigeria
W. W. D. Modder
Affiliation:
Department of Zoology, University of Ibadan, Nigeria
*
Corresponding author: GFT.
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Abstract

The temperature, pH, moisture, carbon and nitrogen contents of soils at oviposition sites of Zonocerus variegatus (L.) (Orthoptera: Pyrgomorphidae) located around cassava farms at Aiyepe, southwestern Nigeria, were compared with those of soils at non-oviposition sites (control) during different months. Although oviposition site soils did not differ in particle composition from control soils, their temperatures were, generally, significantly lower. Soils at oviposition sites lost significantly less organic carbon to oxidation and nitrogen to leaching. They also contained significantly more moisture than soils at control sites during February-April when oviposition occurred and newly deposited eggs, lacking the serosal cuticle, would be prone to desiccation in dry soils. Conditions at oviposition sites are a key factor in the selection of egg deposition by gravid Z. variegatus.

Résumé

La température, le PH, le taux d'humidité, le carbone et la teneur en azote ont étaient mesurés dans les sols aux sites de ponte de Zonocerus variegatus (L.) (Orthoptère: Pyrgomorphidae). Ces sites étaient localisés près des champs de manioc à Aiyepe, au sud-oeust du Nigeria et leurs sols ont été comparés aux sols en dehors des sites de ponte (témoin), au cours des mois différentes. Même si les sols sur les sites de ponte n'ont pas différé des sols témoins de part leur composition granulométrique, leurs températures étaient en général significativement basses. Les sols sur les sites de ponte perdaient moins de carbone organique dans le processus d'oxydation et moins d'azote dû au lessivage. L'humidité dans les sols des sites de ponte était plus élevée que celle dans les sols des sites témoins de fevrier à avril, les mois pendant lesquels la ponte avait lieu et où les oeufs pondus dans des sols secs étaient condamnés à la dessication suite au non-revêtement de cuticle séreuse. Les conditions prévalentes sur les sites de ponte constituent un facteur déterminant dans le choîx du lieu de ponte par les femelles gravides.

Type
Research Articles
Copyright
Copyright © ICIPE 1997

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References

REFERENCES

Barker, D., Oguntoyinbo, J. and Richards, P. (1977) The utility of the Nigerian peasant farmer's knowledge in monitoring of agricultural resources: A general report. Rep. No. 4. Monitor. Assess. Rep. Cent. Lon. 53 pp.Google Scholar
Bouyoucos, G. J. (1927) The hydrometer as a new method for the mechanical analyses of soils. Soil Sci. 23, 343353.CrossRefGoogle Scholar
Chapman, R. F. and Page, W. W. (1978) Embryonic development and water relations of the eggs of Zonocerus variegatus (L.) (Acridoidea: Pyrgomorphidae). Acrida 7, 243252.Google Scholar
Chapman, R. F., Page, W. W. and Cook, A. G. (1979) A study of population changes in the grasshopper, Zonocerus variegatus in southern Nigeria, J. Anim Ecol. 48, 247270.CrossRefGoogle Scholar
Chapman, R. F., Page, W. W. and McCaffery, A. R. (1986) Bionomics of the variegated grasshopper, Zonocerus variegatus in west and central Africa. Annu. Rev. Entomol. 31, 479505.CrossRefGoogle Scholar
Day, P. R. (1953) Experimental confirmation of hydrometer theory. Soil Sci. 75, 181186.CrossRefGoogle Scholar
Hunter-Jones, P. (1961) Rearing and Breeding Locust in the Laboratory. Anti-locust Research Centre. Lon. 12 pp.Google Scholar
Hunter-Jones, P. (1964) Egg development in the desert locust (Schistocerca gregaria Forsk) in relation to the availability of water. Proc. R. ent. Soc. Lon. 39, 2533.Google Scholar
Hussain, M. A. and Ahmad, T. (1936) Studies on Schistocerca gregaria Forsk II. The biology of the desert locust with special relation to temperature. Indian J. Agric. Sci. 6, 188262.Google Scholar
Jackson, M. L. (1962) Soil Chemical Analysis. Prentice Hall, New York.Google Scholar
Jenny, H. (1930) A study of the influence of climate upon the nitrogen and organic matter content of the soil. Mo. Am. Agr. Expt. Res. Bull. 152, 66 pp.Google Scholar
Juo, A. S. R. (1979) Selected methods for soil and plant analysis. International Institute of Tropical Agriculture, Ibadan. 70 pp.Google Scholar
Lal, R. (1988) Effects of macrofauna and soil properties in tropical ecosystems, pp. 101116. In Biological Interactions in Soil (Edited by Edwards, C. A., Stinner, E. R., Stinner, D. and Rabatin, S.). Elsevier Sci. Publishing Co. Inc. NY.Google Scholar
McCaffery, A. R. and Page, W. W. (1982) Oviposicion behaviour of the grasshopper Zonocerus variegatus. Ecol. Ent. 7, 8590.CrossRefGoogle Scholar
Modder, W. W. D. (1978) Respiratory and weight changes, and water uptake, during embryonic development and diapause in the African grasshopper Zonocerus variegatus (L.) (Acridoidea: Pyrgomorphidae). Acrida 7, 253265.Google Scholar
Page, W. W. (1978) Destruction of eggs as an alternative to chemical control of the grasshopper pest Zonocerus variegatus (L.) (Orthoptera: Pyrgomorphidae) in Nigeria. Bull. ent. Res. 68, 575581.CrossRefGoogle Scholar
Page, W. W. and McCaffery, A. R. (1979) Characteristics and distribution of oviposition sites of the grasshopper pest Zonocerus variegatus (L.). Ecol. Ent. 4, 177288.CrossRefGoogle Scholar
Shulov, A. (1952) The development of eggs of Schistocerca gregaria (Forskal) in relation to water. Bull. ent. Res. 43, 469476.CrossRefGoogle Scholar
Tamu, G. F. (1995) Location and categorization of Zonocerus variegatus (Orthoptera: Acridoidea: Pyrgomorphidae) egg pods and evaluation of egg destruction as a control measure, J. Afr. Zool. 109, 329338.Google Scholar
Toye, S. A. (1971) Notes on the biology of Zonocerus variegatus (Orthoptera: Acridoidea) in western state of Nigeria. Rev. Zool. Bot. Afr. 48, 384392.Google Scholar
Walkley, A. and Black, I. A. (1934) An examination of the Degtjareff method for determining soil organic matter and proposed modification of the chromic acid titration method. Soil Sci. 37, 2938.CrossRefGoogle Scholar