【摘要】 本文定期测定了感病品种ＮＣ８９接种ＰＶＹＮ后叶片内６种酶活性的动态变化，结果表明，接种后１４天内ＳＯＤ活性均较对照增高，其中第８天达高峰值，但接种后第１６天ＳＯＤ活性低于对照约２８％；ＡＡＯ活性在接种后２～６天明显高于对照，６～１２天，ＡＡＯ活性变化不定，但１２天后，ＡＡＯ活性又升高；ＰＯＤ活性在接种后２～４天比对照降低，４天后显著升高，至接种后第１４天达高峰值，接种后１６天又有下降趋势；ＣＡＴ活性仅在接种后第２天比对照略有升高，随后均低于对照，其中第６天和第１０天ＣＡＴ活性降低幅度较大；ＰＡＬ活性在接种后２～６天均比对照高，随后开始下降，第８～１０天ＰＡＬ活性低于对照，１０天后又升高，第１２天又达高峰值；ＰＰＯ活性在接种后２～１６天明显高于对照。本文还详细讨论了上述６种酶与烟草脉坏死病病程的相关性。更多还原

【Abstract】 The activities of six enzymes were evaluated on leaf tissue of susceptible tobacco variety NC89 after PVYN infection. Results showed that SOD activity increased significantly during the 14 days after inoculation, and it reached the highest peak on the 8th day after inoculation,but the activity of SOD on the 16th day was about 28% lower than that of the control. AAO activities were distinctly greater than those of the control from 2 to 6 days after inoculation but they changed irregularly from 6 to 12 days, however, they went up afterwards.The activity of POD reduced from 2 to 4 days after inoculation but increased notably 4 days later and reached the highest peak on the 14th day, then tended to fall down 16 days after inoculation, but it was still higher than that of the control. CAT activity increased slightly only on the 2nd day but were lower than those of the control from 4 to 16 days after inoculation,while the reduction ranges were greater on the 6th day and the 10th day. The PAL activities were higher than those of the control from 2 to 6 days after inoculation,but tended to decrease and lower than those of the control from 8 to 10 days, then they went up again and reached the highest peak on the 12th day.PPO activities were higher than those of the control during the 16 days after inoculation. This paper also gives detailed discussion on the relationship between the enzyme activity and the pathogenesis.更多还原