Figure 7.

OsWRKY76 and OsWRKY62 knockout plants exhibit enhanced defense responses. A, Levels of alternative transcripts of OsWRKY76 and OsWRKY62 were determined by RT-PCR analysis. The leaf samples were collected from 8-week-old knockout (KO) and regenerated nontransgenic (NT) plants. B, Transcript levels of defense genes were determined by qRT-PCR using rice UBQ as a reference. Expression levels in the knockout lines are shown relative to that in regenerated nontransgenic rice leaves. Values shown are means ± se of three replicates. The amounts of momilactone A, phytocassanes B, and phytocassanes C were determined by liquid chromatography-tandem mass spectrometry using lidocaine as an internal standard. Data are means ± se of two replicates. *, P < 0.05 and **, P < 0.01 (Student’s t test). C, Detached leaves of 8-week-old plants were inoculated with M. oryzae SZ (1 × 10⁵ spores mL⁻¹). Photographs were taken 6 d post inoculation. Lesion lengths are averages of 10 inoculated sections. Values marked with different letters indicate significant differences as analyzed by the SAS software (Duncan’s multiple range test, α = 0.05). Bar = 0.5 cm.