Figure 3.

Influence of ralfuranones on the formation of microcolonies of 1–5 μm in diameter (a), immature mushroom‐type biofilms (mBFs) of 5–10 μm in diameter (b) and mature mBFs of >10 μm in diameter (c) by Ralstonia solanacearum strains. Cells of R. solanacearum strain OE1–1, the ralfuranone‐deficient mutant (ΔralA), with or without application of ralfuranones A, B, J, K or L at concentrations of 20 μm, and the complemented ΔralA mutant (ralA‐comp) incubated in tomato apoplast fluid on nano‐percolators were observed under a scanning electron microscope. Bars indicate the standard errors. Asterisks indicate a significant difference from ΔralA (P < 0.05, t‐test).