1-aminocyclopropane-1-carboxylic acid oxidase genes (ACO4 and ACO1) and ACC synthase genes (ACS2, ACS6 and ACS7) encoding proteins involved in ET biosynthesis, and ERF1, PR3 and PR4 [57], which are induced by treatment with JA or ET, were all upregulated during infection (cluster VII, S7 Table). Here, ACO1 is linked to infection.