Comparative microarray-based transcriptome analysis of A. thaliana mlo2 mlo6 mlo12 mutants and wild type plants upon Golovinomyces orontii inoculation revealed an increased and accelerated accumulation of many defense-related transcripts. Despite the biotrophic nature of the interaction, this included the non-canonical activation of a jasmonic acid/ethylene-dependent transcriptional program. Overall design: Microarray analysis was performed in triplicates with 4-week-old A. thaliana wt (Col-0) and mlo2 mlo6 mlo12 plants that were sampled either prior (0 h) or 8 and 12 h after inoculation with G. orontii.