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Some Factors Pertaining to Coffee Shoots and Within Canopies Affecting The Distribution of Yellow-Headed Borer, Dirphya Nigricornis Olivier (Coleoptera: Cerambycidae) Egg Niches in Kenya

  • F. M. E. WanJala
  • B. M. Khaemba
Research Article

Abstract

The plant factors that contribute to the abundance of beetles in coffee fields were studied and analysed relative to shoot and canopy features of the host plant. During infestation Dirphya nigricornis Olivier constructed niches within specific heights (145.0–210.0 cm) of the canopies such that there was a highly significant (r =0.99, P =0.001) availability of adequate habitat for larval development. The adaptation of the pest to the host plant was good, irrespective of varieties and culture systems of the coffee plant. It was concluded that the alignment of eggs to tip internodes synchronised the newly hatched larvae with the coffee tissues, usually between 0.5 to 30 cm off the shoots, of extremely low dry matter, and high moisture content, such factors favouring early larval development.

Key Words

Dirphya nigricornis coffee cultivars egg niches off tip location canopy pest incidence 

Résumé

Les facteurs végétaux qui contribuent a l’abondance des D. nigricornis dus les caféiers. Ont ete étudiés relatifs aux jeunes pousses et aux couverts végétaux. L’infestation se fait par la construction des nids a une haunter specifique (145 a 210 cm) favorable au dévelopement larraire. Cette observation serant uraie pour tait systeme de culture et toute variete cultivee. L’emplacement d’oeufs tout an long des internoeuds se fait de façon synchrone avec le closion des larves sur le dévelopment tittulaire des jeunes pousses, en général de 0, 5 a 30 cm, region qui correspond a une faible teneur de matiere seche mais a une forte teneur en eau.

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References

  1. Crowe F. J. (1962) The biology and control of Dirphya nigricornis Olivier, a pest of coffee in Kenya (Coleoptera: Cerambycidae), J. ent. soc. Sth Africa 25, 304–312.Google Scholar
  2. Delcomyn F. (1985) Factors regulating insect walking. A. rev. Ent. 30, 329–356.CrossRefGoogle Scholar
  3. Dethier V. G. (1970) Chemical interactions between plants and insects. In Chemical ecology (Edited by Sondheiner E. and Someone J. B.), pp. 83–102. London Academic Press.CrossRefGoogle Scholar
  4. Grimble D. G., Nord J. C. and Knight F. B. (1969) Oviposition characteristics and early larval mortality of Saperda inornata and Oberea schaumii in Michigan aspen. Ann. ent. Soc. Am. 62, 308–31.CrossRefGoogle Scholar
  5. House H. L. (1961) Insect nutrition. A. rev. Ent. 6, 13–26.CrossRefGoogle Scholar
  6. Lashomb H. L. and Nebeker T. E. (1970) Investigations of egg niches, eggs, and rate of oviposition of Dendroctonus frontalis (Coleoptera: Scolytidae). Can, Ent. 111, 435–438.CrossRefGoogle Scholar
  7. Le Pelley R. H. (1959) Agricultural insects of East Africa. East Africa High Commission, Nairobi, Kenya, 305 pp.Google Scholar
  8. Mathews E. G. (1976) Insect ecology. University of Queensland Press.Google Scholar
  9. Maxwell F. G. and Jennings P. R. (1980) Breeding plants resistant to insects. John Wiley and sons, 683 pp.Google Scholar
  10. Mayr R. (1970) Populations, species and evolution. Cambridge Mas: The Belknap Press, Harvard University Press.Google Scholar

Copyright information

© ICIPE 1987

Authors and Affiliations

  • F. M. E. WanJala
    • 1
  • B. M. Khaemba
    • 2
  1. 1.Coffee Research FoundationRuiruKenya
  2. 2.Department of ForestryMio UniversityEldoretKenya

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