Figure 3.

clp1 Is Required for Proliferation in Planta during Pathogenic Development.

Infected leaves were stained with Chlorazole Black E 3 d after inoculation. Hyphae of the solopathogenic strains UMS71 (a1mfa2bE1/bW2:NLS-3xeGFP) (A) and CL13 (a1bE1/bW2) (B) form clamp-like structures in planta (arrows). Hyphae of strain UMS71Δclp1 can form appressoria ([C1], arrow; focus on the leaf surface) and penetrate, but clamp-like structures are not observed. Fungal proliferation stops at latest when the hyphae have grown through two to three plant cells ([C2]; focus within the epidermal cell layer). The site of penetration is marked with an arrow.