Figure 1.

Effect of humidity on cpr22 phenotypes. A, Morphology, chlorotic phenotypes, and spontaneous cell death formation of 4-week-old cpr22 and Ws-wt plants grown under 65% RH (top row), under 95% RH (middle row), or under 95% RH and shifted to 65% RH for 2 d (bottom row) at 22°C. B and C, Growth of H. arabidopsidis Emwa1 on Ws-wt and cpr22 plants grown under 65% or 95% RH conditions. Cotyledons of 7-d-old seedlings were inoculated with H. arabidopsidis Emwa1 (10⁶ spores mL⁻¹). At 7 d post infection, infected cotyledons were stained by trypan blue to visualize pathogen growth (B) or the number of sporangiophores on two cotyledons per plant was determined (C). Experiments were done three times with similar results. Bars = 1 cm (plants) and 125 μm (trypan blue staining).