A Eucalyptus bacterial wilt isolate from South Africa is pathogenic on Arabidopsis and manipulates host defences

S. Naidoo, J. Fouché-Weich, P. Law, K. J. Denby, Y. Marco, D. K. Berger*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Ralstonia solanacearum, the causal agent of bacterial wilt, has been reported from Eucalyptus plantations in at least three countries in Africa. The lack of genomics resources in Eucalyptus species led us to develop and study a pathosystem between a previously characterized South African isolate and the model plant Arabidopsis thaliana. Ralstoniasolanacearum BCCF401 isolated from a Eucalyptus grandis×Eucalyptus camaldulensis hybrid was shown to cause disease on A.thaliana ecotype Col-5. Arabidopsis genomics tools were exploited to investigate gene expression changes during wilt disease development, and thereby develop hypotheses that can be tested in Eucalyptus once genomics resources are available. Transcriptome analysis using 5000 A.thaliana ESTs was performed and revealed 141 genes that were differentially regulated by R.solanacearum infection (at a significance threshold of p- mutant. A subset of the genes which were induced by PAMPs were repressed by R.solanacearum infection, and vice versa, suggesting that these genes may be repressed or induced, respectively, by specific R.solanacearum effectors. We hypothesize that these genes represent targets of R.solanacearum effectors. The pending release of the Eucalyptus genome sequence will enable orthologues to be identified and these hypotheses to be tested in Eucalyptus trees.

Original languageEnglish
Pages (from-to)101-113
Number of pages13
JournalForest Pathology
Issue number2
Publication statusPublished - Apr 2011

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