Host-parasite interactions in clubroot of crucifers. (Special Issue: Clubroot (Plasmodiophora brassicae) on canola and other brassica species: disease development, epidemiology and management.)

摘要

Clubroot, caused by Plasmodiophora brassicae, is an important root disease of crucifers worldwide. In this review, the molecular aspects of clubroot pathogenesis and resistance are discussed. Topics covered include recent studies on the processes associated with infection by primary and secondary pathogen zoospores, examination of the expression patterns of P. brassicae genes at different stages of infection, and the concurrent identification of candidate genes for functional studies. Although the whole genome sequence of P. brassicae is not yet available, molecular studies of the pathogen are nonetheless moving into the genomics era. Transcriptomics and functional analyses of individual genes involved in the P. brassicae/Brassica interaction have recently been conducted to complement studies on the excellent model host, Arabidopsis thaliana. Two resistance genes have been cloned and their molecular functions illustrated, supporting suggestions that the clubroot pathosystem follows the gene-for-gene model. Although much about the pathogenesis of clubroot remains unknown, significant advances have been made in recent years, which may facilitate the identification of targets for agro-chemical development and resistance breeding.