Tricyclazole induced expression of genes associated with rice resistance

Objective This study aims at analyzing both the dynamics and the correlations with rice blast resistance of rice defense related gene expression under tricyclazole treatment.

Method Antifungal activity of tricyclazole was determined indoor under greenhouse conditions. Real-time PCR analysis was performed to monitor the expression levels of rice defense related genes after tricyclazole treatment.

Result Rice blast fungus mycelium growth and spore germination were not inhibited by tricyclazole. However, tricyclazole treatment 24 h after rice blast fungus inoculation could still help 87.2% of the rice strains to successfully defense the fungi. RT-qPCR results showed that rice defense related genes OsNH1-1, OsPR1a and OsPR10 were induced by tricyclazole. Moreover, by analyzing the expression of key genes in the salicylic acid and jasmonic acid pathways, the key genes of OsLOX and OsAOS2 from the latter one were significantly induced by tricyclazole treatment.

Conclusion The prevention of rice blast by tricyclazole is not only by inhibiting the synthesis of melanin. RT-qPCR results show that tricyclazole can trigger rice resistance by inducing expression of key genes in the jasmonic acid pathway.