TMV侵染不同抗性番茄品种之后引起的过氧化物酶活性及同工酶的变化

 本文论述了不同抗性番茄品种在接种了TMV之后体内过氧化物酶及其同工酶的变化趋势。不同品种番茄幼苗接种TMV之后30天内病毒含量、过氧化物酶活性及其同工酶的测定结果表明:所有接种的番茄幼苗与健株对照相比均表现酶活性的增强及酶带数目的增多;但不同抗性品种,酶活性交化曲线及同工酶谱带的变化趋势有所不同:感性品种北京早红(+/+)及耐病品种强力米寿接种TMV之后,病毒含量迅速上升,在第15天达到最高峰,同时植株开始显症,其酶活性曲线呈现出1个增值高峰,即酶活性只在显症之后迅速上升于第24天达到最高峰,病株在症状发展过程中产生2条健株所没有的具高迁移率的同工酶谱带A与B。抗性品种Tm-2(Tm-2/+)抑制TMV在体内的增殖,在接种之后30天内植株不表现典型外部症状,其酶活性曲线具有2个增酶高峰,即在接种后第12天达到最高峰,并在第21天有1个新的高峰;在酶活性高峰期,接种植株也产生同工酶谱A与B,与感性品种不同的是谱带A与B形成较早,同时,抗性品种还产生感病品种所没有的1条同工酶谱带F。上述过氧化物酶活性及同工酶的变化趋势可以成为鉴定品种抗性一个有价值的生化指标。

CHANGES OF PEROXIDASE ACTIVITY AND ISOPEROXIDASES IN TOMATO PLANTS OF DIFFERENT RESISTANCE INFECTED BY TOBACCO MOSAIC VIRUS(TMV)

Virus multiplication,peroxidase activity and isoperoxidases were investigated with leaves of resistant,tolerant and susceptible tomato cultivars at two days interval up to 30days after inoculation of TMV.Virus infection resulted in an increase in peroxidase activity and changes in isoperoxidase patterns.In tolerant and susceptible cultivars,coinciding with TMV multiplication and symptom development,the peroxidase activity increased greatly after 15 days of inoculation and reached a maximum after 3 weeks of inoculation.Two additional isoperoxidase bands A and B appeared in the case of infected plants,whereas in healthy plants,only 6 isozyme bands occured at the peak of peroxidase activity.In resistant cultivar,TMV multiplication was inhibited so that the infected plants were almost symptomless,however,the peroxidase activity increase was associated with appearance of isoperoxidases A and B at the 12th day and 21th day after TMV inoculation.