Rhizoctonia solani AG8 infection of wheat seedling roots

Rhizoctonia solani is a nectrotrophic fungal pathogen that causes billions of dollars of damage to agriculture worldwide and infects a broad host range including wheat, rice, potato and legumes. In this study we identify wheat genes that are differentially expressed in response to the R. solani isolate, AG8-1, using microarray technology. A significant number of wheat genes identified in this screen were involved in ROS production and redox regulation. Levels of ROS species were increased in wheat root tissue following R. solani infection as determined by NBT, DAB and titanium sulphate measurements/stainings. Pathogen/ROS related genes from R. solani were also tested for expression patterns upon wheat infection. TmpL, a R. solani gene homologous to a gene associated with ROS regulation in Alternaria brassicicola, and OAH, a R. solani gene homologous to oxaloacetate acetylhydrolase which has been shown to produce oxalic acid in Sclerotinia sclerotiorum, were highly induced in R.solani when infecting wheat. We speculate that the wheat germin-like protein (GLP) is induced to inactivate the oxalic acid that is produced by the R. solani OAH. infected vs mock-infected seedlings, 3 biological replicates