DEFENCE GENES AND ANTIOXIDANT ENZYMES IN STAGEDEPENDENT RESISTANCE TO RICE NECK BLAST
Z.N. Hao, L.P. Wang, R.X. Tao
The rice variety Jiajing3768 is susceptible to neck blast at the booting stage (BS) but resistant at the full heading stage (FHS). This variety was used to analyze the inducible expression of defence genes and activities of antioxidant enzymes in the necks, at both the BS and FHS, after inoculation with Magnaporthe oryzae. We found that defence genes PR1b (pathogenesis-related class 1b), PBZ1 (probenazole-inducible gene), PAL (phenylalanine ammonia-lyase), and CHS (chalcone synthase) may play roles in the resistance difference to neck blast between the BS and FHS in Jiajing3768. No significant differences were observed between the BS and FHS in the inducible expression of PR1a, PR4, and JIOsPR10 (jasmonic acid induced PR 10). The antioxidant enzymes superoxide dismutase, peroxidase, catalase, glutathione reductase, and malondialdehyde coordinately participated in the stage-dependent resistance difference in Jiajing3768, and that oxidative damage is lower in the necks at the FHS than at the BS.