NaCl胁迫下鲜烟叶中多酚物质含量及PAL和PPO活性变化

为探讨NaCl胁迫对烤烟多酚物质含量的影响,以烤烟NC89为供试品种,在营养液砂培盆栽种植条件下经含350、700 mmol/L NaCl的1/3浓度Hoagland营养液根部胁迫处理,检测分析了植株叶片中多酚物质含量和苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)活性的变化。结果表明,NaCl胁迫处理2 d时叶片类黄酮含量明显增加,处理6 d时绿原酸含量开始增加,处理8 d时芸香苷含量明显增加;花青苷含量随处理时间延长呈先升高后降低的趋势;不同胁迫浓度处理中,绿原酸、类黄酮、芸香苷和花青苷含量以350 mmol/L NaCl处理较高。350 mmol/L NaCl胁迫处理下,PAL活性逐渐升高,并分别与绿原酸、芸香苷含量呈极显著、显著正相关。胁迫处理后PPO活性逐渐升高,且与绿原酸含量有一定相关性。总之,适度NaCl胁迫处理下鲜烟叶多酚物质含量增加,且与PAL活性变化密切相关。

Changes of Polyphenols Contents, PPO and PAL Activities of Fresh Tobacco Leaves under NaCl Stress

A pot experiment with flue-cured tobacco NC89 planted in sand and three treatments (0, 350, 700 mmol/L NaCl with 1/3 Hoagland nutrient solution) was carried out to study the effect of NaCl stress on polyphenols of tobacco leaves and changes of polyphenols contents. The results showed that the flavonoid content increased significantly after 2 days of NaCl stress and the chlorogenic acid content began to increase after 6 days of NaCl stress. The rutin content increased significantly after 8 days of NaCl stress. The anthocyanin content first increased and then decreased. In different stress concentrations, the contents of chlorogenic acid, flavonoid, rutin, and anthocyanin were the highest in 350 mmol/L NaCl solution. PAL activity gradually increased, and had high significantly positive correlation with chlorogenic acid content and had positive correlation with rutin content at 350 mmol/L NaCl solution stress. PPO activity gradually increased and had correlation with chlorogenic acid. In general, the content of polyphenols increased and was closely related to change of PAL activity under the moderate NaCl stress treatment.