烟草感染PVY^N后叶脉坏死与总酚、类黄酮及PPO关系研究

Relationship among total phenol,flavonoid and PPO activity with the necrosis of tobacco infected by PVY^N

本文采用常规摩擦接种和比色法研究了烟草感染PVYN后叶脉坏死与总酚、类黄酮及PPO的关系。试验结果表明:感病品种K326接种PVYN后总酚和类黄酮含量升高,且接种处理与未接种对照间总酚和类黄酮含量的差别随症状表现的加重有递增趋势;就部位而言,与根部及叶部相比,坏死严重的叶脉中总酚和类黄酮含量增加幅度最大,其含量分别增加了149.23%和152.97%;其PPO活性在接种PVYN后3d时出现第一个高峰,比对照高213.61%,随后降至最低,但仍比对照高130.77%,在接种PVYN后15d,坏死症状表现严重时,又迅速升高。抗病品种VAM接种PVYN后无异常症状,其总酚和类黄酮含量也升高,但升高幅度不大,不同部位总酚及类黄酮含量增加的幅度也均小于25%,其PPO活性在接种PVYN后稍有升高,但基本保持一个水平。

The relationship of PVY^N infection on the vein necrosis and total phenol, flavonoid and PPO activity in leaves of tobacco was evaluated. The results showed that the content of total phenol and flavonoid increased in susceptible variety K326 when inoculated with PVY^N. The total phenol and flavonoid in seriously necrotic vein were the highest compared with the leaf tissue and root, the increase rates were 149.23% and 152.97% respectively. The first peak of PPO activity appeared at the 3^th d after inoculation which higher than the control for 213.61%, and then decreased to the lowest but still higher than the control for 130.77%, the PPO activity increased again at the 15^th d after inoculation while the symptom was seriously. Resistant variety VAM showed no obvious symptom after inoculation, and the content of total phenol and flavonoid were increased less than 25% in different parts of plants, and the activity of PPO only had a few increase after inoculation with PVY^N but maintained at the same level.