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Australasian Plant Pathology

, Volume 35, Issue 1, pp 77–80 | Cite as

Use of optical density as a measure of Claviceps africana conidial suspension concentration

  • D. J. Herde
  • M. J. Ryley
  • S. D. Foster
  • V. J Galea
  • R. G. Henzell
  • D. R. Jordan
Short Research notes

Abstract

Sorghum ergot, caused by Claviceps africana, has remained a major disease problem in Australia since it was first recorded in 1996, and is the focus of a range of biological and integrated management research. Artificial inoculation using conidial suspensions is an important tool in this research. Ergot infection is greatly influenced by environmental factors, so it is important to reduce controllable sources of variation such as inoculum concentration. The use of optical density was tested as a method of quantifying conidial suspensions of C. africana, as an alternative to haemocytometer counts. This method was found to be accurate and time efficient, with possible applications in other disease systems.

Additional keywords

colorimeter inoculum concentration light transmittance Sorghum bicolor 

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Copyright information

© Australasian Plant Pathology Society 2006

Authors and Affiliations

  • D. J. Herde
    • 1
    • 2
  • M. J. Ryley
    • 3
  • S. D. Foster
    • 4
  • V. J Galea
    • 1
  • R. G. Henzell
    • 5
  • D. R. Jordan
    • 5
  1. 1.School of Agronomy and HorticultureUniversity of QueenslandGattonAustralia
  2. 2.Department of Primary Industries and FisheriesLeslie Research CentreToowoombaAustralia
  3. 3.Department of Primary Industries and FisheriesToowoombaAustralia
  4. 4.Biometrics SAThe University of AdelaideGlen OsmondAustralia
  5. 5.Department of Primary Industries and FisheriesHermitage Research StationWarwickAustralia

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