The molecular mechanisms underlying methyl jasmonate (MeJA) primed defense against Rhizopus stolonifer through regulating phenylpropanoid pathway in peaches and the involvement of WRKY transcription factor were investigated. MeJA treatment enhanced the activity of phenylalanine ammonia-lyase (PAL) and 4-coumarate-CoA ligase (4CL), and promoted the accumulation of total phenolics, total flavonoids and lignin content as well as the main individual phenolic compounds, including chlorogenic acid, neochlorogenic acid and epicatechin. Moreover, transcripts of PpPAL and Pp4CL transcription were substantially and rapidly enhanced upon inoculation with the pathogen in MeJA-treated fruit, indicating that MeJA triggered a priming defense via enhancing phenylpropanoid pathway in peaches. Furthermore, MeJA primed the expression of PpWRKY70, which was identified as a transcription activator of PpPAL and Pp4CL via binding to their W-boxes. Taken together, our results demonstrate that PpWRKY70 is involved in the MeJA-primed defense by activating the phenylpropanoid pathway.

茉莉酸甲酯底层涂底漆防御的分子机制（茉莉酸甲酯）软腐病通过调节在桃子苯丙素途径和WRKY转录因子的参与进行了调查。MeJA处理提高了苯丙氨酸解氨酶（PAL）和4-香豆酸酯-CoA连接酶（4CL）的活性，并促进了总酚，总黄酮和木质素含量以及主要的酚类化合物（包括绿原酸）的积累新绿原酸和表儿茶素。此外，PpPAL和Pp4CL的转录本在用MeJA处理的水果中接种病原菌后，转录水平得到了显着而迅速的增强，这表明MeJA通过增强桃中的苯丙烷途径触发了启动防御。此外，MeJA引发了PpWRKY70的表达，PpWRKY70通过与W-box结合而被鉴定为PpPAL和Pp4CL的转录激活因子。两者合计，我们的结果表明PpWRKY70通过激活苯丙烷途径参与了MeJA启动的防御。