Plant Protect. Sci., 2002, 38(10):S69-S72 | DOI: 10.17221/10323-PPS

Plasmodiophora brassicae, the causal agent of clubroot disease, may penetrate plant cell walls via cellulaseOriginal Paper

I. Mühlenberg, A. Schuller, J. Siemens, P. Kobelt, J. Ludwig-Müller

¹ Institute of Botany, Technical University Dresden, 01062 Dresden, Germany

² Institute of Applied Genetics, Freie University Berlin, 14195 Berlin, Germany Tel.: +49 351 463 33939, Fax: +49 351 463 37032, E-mail: jutta.ludwig-mueller@mailbox.tu-dresden.de

Plasmodiophora brassicae causes the clubroot disease of Brassicaceae by its obligate biotrophic lifestyle within host roots. The pathogen enters the root cortex, but is soon found near the vascular tissue. There are basically two possibilities for the distribution of Plasmodiophora within the root tissue: 1. distribution by simultaneous division with the host cell or 2. by active migration from cell to cell. It has been shown that plasmodia of the pathogen are indeed able to penetrate plant cell walls. We have therefore begun to isolate a cellulase gene from the pathogen by using degenerated primers to different fungal cellulases. It was possible to amplify specifically a fragment from infected roots 14 days after inoculation which was not present in healthy roots and later time points of infection. The fragment was sequenced and showed high homology to various fungal cellulases. Cloning of the complete cDNA and expression analysis of the putative Plasmodiophora cellulase is in progress.

Keywords: Brassica rapa ssp. pekinensis; cellulase; host cell wall lysis; Plasmodiophora brassicae

Published: June 30, 2002  Show citation