New aspects on the infection mechanism of Botrytis cinerea Pers

Abstract

With the help of active types of oxygen, extracellular enzymes and mechanical processes, Botrytis cinerea is capable of infecting plant tissue. Whereas no clear correlation was found between the activities of protease, pectolytic or other cell wall degrading enzymes and virulence, a positive correlation between pathogenicity and the intensity of active types of oxygen released was apparent in some isolates. It is assumed that these toxins result from the activity of glucose or xylose oxidases. Antioxidants inhibited the infection. It is concluded from these results, that active types of oxygen play a decisive role in the infection process.

The BOTRYTIS SUSCEPTIBLE1 Gene Encodes an R2R3MYB Transcription Factor Protein That Is Required for Biotic and Abiotic Stress Responses in Arabidopsis

“…At 2 days after inoculation, the bos1 plants exhibited larger and more intensely stained areas for O 2 Ϫ and H 2 O 2 than did wild-type plants (Figures 5D and 5H). This finding correlates well with the increased fungal accumulation at 2 days after inoculation in bos1 plants and the increased tissue maceration that results in enhanced production of ROI, consistent with previous reports (Edlich et al, 1989;Tiedemann, 1997). Early disease symptoms in bos1 include a very distinct spreading chlorosis that surrounds the infection sites.…”

“…This difference may be attributable to the increased fungal growth and tissue maceration in mutant plants. This finding is consistent with the increased ROI formation in Botrytis-infected tissues that correlates with fungal biomass and disease severity (Edlich et al, 1989).…”

“…By contrast, necrotrophic pathogens such as Sclerotinia sclerotiorum and Botrytis may induce toxic levels of ROI in the host to promote infection (Govrin and Levine, 2000). With Botrytis, a positive correlation between pathogenicity and the intensity of ROI has been reported (Edlich et al, 1989). The inhibition of ROI formation in the host reduces susceptibility to Botrytis (Govrin and Levine, 2000).…”

The Membrane-Anchored BOTRYTIS-INDUCED KINASE1 Plays Distinct Roles in Arabidopsis Resistance to Necrotrophic and Biotrophic Pathogens

“…Whereas necrotrophic pathogens induce cell death in their hosts by secreting toxic substances into host tissue before and during colonization, biotrophic pathogens require living cells to complete their life cycle. The necrotroph Botrytis cinerea produces cell wall-degrading enzymes (Prins et al, 2000), toxic levels of reactive oxygen intermediates (Edlich et al, 1989;Deighton et al, 1999;Muckenschnabel et al, 2002), and toxins (Tiedemann, 1997;Colmenares et al, 2002) that result in the death and maceration of tissue, leading to plant decay. Evidence to date strongly suggests a limited role for SAR and gene-for-gene (race-specific) resistance against necrotrophic pathogens in Arabidopsis thaliana.…”

Efficacy of resistance inducers, free‐radical scavengers and an antagonistic strain of Pseudomonas fluorescens for control of Rhizoctonia solani AG‐4 in bean and cucumber

“…Several natural and synthetic chemicals have been reported to control a broad range of fungal, bacterial and viral diseases in various plant species by inducing local and systemic resistance through diverse mechanisms Kessmann et al, 1994;Cohen, 1996;Görlach et al, 1996;Kalix et al, 1996). In addition, several antioxidant compounds are reported to control both necrotrophic and biotrophic fungal pathogens in several crops, chiefly by negating the effects of free radicals produced during pathogenesis (Prusky, 1988;Arnoldi et al, 1989;Edlich et al, 1989;Elad, 1992;Weigend & Lyr, 1996). These investigations have focused mostly on foliage pathogens, and relatively few attempts have been made to investigate induced resistance against root infecting fungal pathogens.…”