Transcriptome Change by Rice Blast Infection in Rice Leaves at Different Growth Phase

Plants undergo various morphological and physiological changes by the transition from juvenile phase to adult phase during the vegetative growth. The key regulator of this vegetative phase transition is micro RNA, miR156, which is involved in various biotic and abiotic stress tolerance. In rice, knockdown of miR156 resulted in the enhanced resistance to rice blast, which was attributed to the up-regulation of WRKY45 at the downstream of miR156. Therefore, it was expected that resistance to rice blast would be enhanced in adult phase along with the down-regulation of miR156 compared with juvenile phase. To test this hypothesis, we compared rice blast resistance and transcriptome in rice leaves at different growth phase. The second and fourth leaves of rice variety "Nipponbare" were inoculated with rice blast conidia, and RNA was extracted from the leaf disk including lesion area sampled 48 hours after inoculation.