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Current Genetics

, Volume 46, Issue 6, pp 357–365 | Cite as

Microsatellite markers reveal genetic differentiation among populations of Sclerotinia sclerotiorum from Australian canola fields

  • Adrienne C. Sexton
  • Barbara J. Howlett
Research Article

Abstract

Eight microsatellite markers were applied to 154 Sclerotinia sclerotiorum isolates from four Australian canola fields, to determine the extent of genetic variation and differentiation in populations of this pathogen. A total of 82 different haplotypes were identified and in each population many haplotypes were unique. Mycelial compatibility grouping, a phenotypic marker system controlled by multiple loci, was often associated with groups of identical or closely related microsatellite haplotypes. Genotypic diversity ranged from 36% to 80% of maximum in the four populations, and gene diversity ranged from 0.23 to 0.79. Genotypic disequilibrium analyses on each of the four populations suggested that both clonal and sexual reproduction contributed to population structure. Analyses based on genetic diversity and fixation indices demonstrated a moderate to high level of differentiation (RST=0.16–0.33, FST=0.18–0.23) between populations from New South Wales and those from Victoria. Despite this genetic diversity, most isolates did not vary in virulence on canola leaves.

Keywords

Sclerotinia sclerotiorum Microsatellite Diversity Population Canola 

Notes

Acknowledgements

We thank Dr. Helen Hayden for constructive comments on the manuscript, Mr. Athol Whitten for technical assistance and Ms. Susan Sprague, Mr. Bruce Wightman, Mr. Anton Cozijnsen and Mr. Harjono for assistance with field sampling. Prof. Linda Kohn, Dr. Elizabeth Aitken, Dr. Merrick Ekins, Ms. Tamrika Hind and Dr. James Wong kindly provided S. sclerotiorum isolates. We are grateful to the Australian Grains Research and Development Corporation for financial support.

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Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  1. 1.School of BotanyThe University of MelbourneParkvilleAustralia

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