Conidiation in ΔFohtf1 mutant.

(A) The wild-type F. oxysporum (WT) and the gene-deletion mutant (ΔFohtf1) strains were assayed for macroconidia production in SNA medium under continuous UV light. (B) WT and ΔFohtf1 strains were assayed for macroconidia production in SNA medium under continuous UV light. (C) WT and ΔFohtf1 strains were grown on SNA medium for 5 days. In the wild-type strain, microconidia were produced from phialides generally in false heads. ΔFohtf1 lacked prototypical false head microconidia but rather formed a windmill-shaped microconidia head (a∼c). Bar = 20 µm. (D) Chlamydospores are formed from hyphae of WT and ΔFohtf1 strains. Bar = 20 µm. (E) Aberrant terminal phialides and macroconidia produce by ΔFohtf1 mutant. tp, terminal phialides; ma, macroconidia; ac, apical cell; bc, basal cell (foot cell). Bar = 20 µm.