Figure 4.

Ypd1 plays a crucial role in asexual development and pathogenesis in M. oryzae. (A) Top panels show top view of the radial vegetative growth of the indicated M. oryzae strains after 10 days on PA medium. Transverse sections (TS) of the vegetative colonies showing aerial hyphal growth in the WT or KD transformants. Arrow depicts fluffy or thin aerial growth in the WT or the KD transformants, respectively. (B) A bar graph depicting total conidiation in the indicated strains of M. oryzae. Total conidia were harvested from 10-day old cultures of the strains grown on PA medium. Data represents mean ± s.e.m. from three independent experiments. (C) Micrographs showing appressorial development, on an inductive hydrophobic surface 24 hpi, by the indicated strain. Black and white arrowheads depict aberrant-shaped and non-melanized appressoria, respectively. Values indicate percentage (mean ± s.e.m. from three replicates) of appressorial development after 24 hpi. Scale bar, 10 μm. (D) Rice sheath was inoculated with the indicated strain of M. oryzae, and observed under bright field optics after 48 hpi. Asterisk shows appressoria on the sheath tissue surface. Black and white arrowheads depict elaborated or restricted fungal invasive hyphae, respectively, of the WT or YPD1 KD transformant in M. oryzae. Scale bar, 10 μm. (E) Detached rice leaf blades were inoculated with the WT or the YPD1 KD transformant conidial suspension, and the disease symptoms were assessed and photographed 7–8 days post inoculation.