根结线虫侵染对番茄叶片保护酶活性的影响

通过对番茄感染南方根结线虫后其叶片中几种保护酶活性的变化进行研究。结果表明:接种南方根结线虫后,番茄叶片中的苯丙氨酸解氨酶(PAL)活性即开始低于对照,随后逐渐恢复至对照水平,15 d之后,酶活性又开始显著低于对照水平,一直持续到第30 d,酶活性恢复到对照水平;多酚氧化酶(PPO)活性变化受线虫侵染的影响较小,在试验期间与对照没有显著性差异;超氧化物歧化酶(SOD)的活性在接种后第1 d即显著低于对照水平,至第7 d的时候恢复至对照水平并持续至第30 d。过氧化物酶(POD)活性在1～20 d均显著高于对照水平。因此,POD活性可以作为早期判断番茄是否感染根结线虫的一项指标。

Effects of Meloidogyne Incognita Infection on Activities of Protective Enzymesin Greenhouse Tomato

Under the infection by Meloidogyne incognita,continuous activity changes of several protective enzymes in tomato leaves were studied.Results showed that after Meloidogyne incognita infecting,the activities of phenylalanine ammonia lyase（PAL） was much lower than that of non-inoculated,and the lower level remained continuously for 7 days till it recovered.Again,the activity was below the level of the control in 15th day’s samples,and this trend continued for 30 days after infection till the second complete recovery.The Meloidogyne incognita infecting had no significant effect on the activities of polyphenol oxidase（PPO）.The activities of superoxide dismutase（SOD） declined in the 1-7 d after inoculated by nematode and its recovery continued to the 30 d.The study found that only peroxidase（POD） activity in the 1-23 d was significantly higher than that of the control level.Therefore,the activity of POD may be used as an early indicator to judge whether the tomato is infected by root-knot nematode.