【摘要】 以鸭梨(Pyrus bretschneideri‘Yali’)为试材,研究外源水杨酸处理后梨叶片中内源水杨酸(SA)及超氧化物歧化酶(SOD)、多酚氧化酶(PPO)同工酶的变化特点以及病程相关基因非表达子 1(NPR1)对水杨酸的早期应答反应。结果表明:水杨酸处理后梨叶片中内源 SA 含量升高,其中游离态SA 含量随处理浓度增大而逐渐升高,但均显著低于对照;结合态 SA 随处理增大而逐渐降低,但均显著高于对照。SOD、PPO 同工酶酶谱分析结果显示,水杨酸处理后酶谱带表达量增强。接种病菌试验表明,0.200 mmol · L-1SA 可以诱导梨增强对轮纹病的抗性,且诱导处理过的叶片受到病菌侵染时 SOD、PPO 酶活性增强。实时荧光定量 PCR 分析表明,0.200 mmol · L-1SA 诱导后梨叶片中 NPR1 表达量明显升高,但NPR1 在茎中的表达受到抑制。更多还原

【Abstract】 The objective of the study is to investigate the effect of exogenous salicylic acid(SA)on superoxide dismutas(eSOD)and polyphenol oxidase(sPPO)isozymes changes and endogenous SA content in pear(Pyrus bretschneideri‘Yali’)leaves and to examine the response of NPR1 gene expression to SA treatment. The results showed that SA at 0.200 mmol · L -1 increased content of total SA was increased in pear leaves. SA treatment increased the content of free states SA with the increase of SA concentration gradually,and the contents were significantly lower than that of control. The content of binding states SA was reduced with the increase of SA concentration gradually,but all treatments were significantly higher than that of control. The isozymes analysis results showed that expression of SOD and PPO isozymes were enhanced,but not new enzymes bands were detected in pear leaves. The experiment of pathogen inoculation suggested that SA at 0.200 mmol · L -1 could induce the resistance of pear leaves to Physalospora piricola Nose significantly. SA treatment enhanced the activities of SOD and PPO,and thereal-time fluorescent quantitative PCR analysis indicated that expression of NPR1 gene were enhanced in pear leaves while was inhibited in stem.更多还原