Figure 5.

Powdery mildew symptoms and visualization of P. xanthii spores on WT/mutant leaves using Trypan Blue. (A) Powdery mildew symptoms on leaf surfaces of WT-ADR27 and CsaMLO mutants at 10 dpi. Typical symptoms could be seen on the WT leaves as a result massive propagation caused by P. xanthii after ten-days post inoculation. Restricted symptoms were detected on P. xanthii inoculated leaves of 4-15, 4-21, and 2-18 plants. Moreover, the hypersensitive response associated lesions were apparent on the leaves of CsaMLO1 ^del and CsaMLO1/11^del plants. However, no symptoms appeared on the leaves of 4-11 and 4-14 plants after ten days of inoculation. (B) The epidermal surface of WT-ADR27 was covered with P. xanthii conidiophore and conidiospores that was newly formed from inoculated spores. Also, massive cell deaths were observed on the leaf mesophyll as a result of pathogen activity apparent from the blue color. However only mycelial growth was detected on the leaves of 4-11 and 4-14 plants, even if there was restricted germination rate.