Suppression of phospholipase D induces defense-related genes and increased disease resistance in rice

Abstract

Phospholipase D (PLD) plays an important role in plant biotic and abiotic stress responses. To study the function of PLD in rice, we made knockdown (KD) plants by introduction of RNAi constructs specific to each PLD gene. The OsPLDβ1- and OsPLDδ2-KD plants were found to exhibit the increased disease resistance to infection of a major fungal pathogen of rice, pyricularia grisea. The up-regulation of defense related genes such as PR-protein genes was observed in the OsPLDβ1-KD plants but not in OsPLDδ2-KD ones. On the other hand, the up-regulation of WRKY family transcription factor genes was observed in both OsPLDβ1- and OsPLDδ2-KD plants. These results suggested that OsPLDβ1 and OsPLDδ2play a negative role in induction of defense reactions through the partly different signal transduction pathways.