Inducible Enrichment of Osa-miR1432 Confers Rice Bacterial Blight Resistance through Suppressing .

MicroRNAs (miRNAs) handle immune response to pathogens by adjusting the function of target genes in plants. However, the experimentally documented miRNA/target modules implicated in the interplay between rice and pv. () are still in the early stages. Herein, the expression of osa-miR1432 was induced in resistant genotype IRBB5, but not susceptible genotype IR24, under strain PXO86 attack. Overexpressed osa-miR1432 heightened rice disease resistance to , indicated by enhancive enrichment of defense marker genes, raised reactive oxygen species (ROS) levels, repressed bacterial growth and shortened leaf lesion length, whilst the disruptive accumulation of osa-miR1432 accelerated rice susceptibility to infection. Noticeably, () was experimentally confirmed as a target gene of osa-miR1432, and the overexpressing transgenic plants exhibited compromised resistance to infestation. Our results indicate that osa-miR1432 and were differently responsive to invasion at the transcriptional level and fine-tune rice resistance to infection, which may be referable in resistance gene discovery and valuable in the pursuit of improving resistance in rice breeding.