铁营养抑制烟草感染TMV及其对钙信使系统调控作用研究

Studies on the regulation of the inhibition of TMV infection and calcium signaling system with iron nutrient treatment

采用液体培养方法,在不同Fe离子浓度处理下,分别采用原子吸收分光光度法和酶联免疫吸附法对感染烟草花叶病毒(TMV)后烟草叶片中的游离钙离子(Ca2+)和钙调素(CaM)含量进行测定,同时对质膜Ca2+-ATPase和氧化型辅酶Ⅰ激酶(NADKase)的活性进行测定,探讨铁营养对烟草感染TMV后的抑制作用,以及对钙信使系统的各个组成成分的调控作用。结果表明,Fe浓度为1.68 mg/L处理时,烟草抗病能力增强,发病时间延迟,症状较轻,烟草叶片中钙离子含量低;CaM含量以及Ca2+-ATPase和NADKase活性均明显高于无Fe处理,表明铁营养在烟草与TMV互作关系中对钙信号系统有一定的调控作用。Ca2+/CaM作为第二信使参与了胞间信号转导,会影响到植物抗病生理反应。

This study was carried out to study the inhibition effect of Fe on tobacco mosaic virus （TMV） infection, and regulation factor on the four composes of calcium signaling system in tobacco leaves. The Ca^2＋ and CaM content was measured by atomic absorption spectrophotometry and ELISA method, respectively. The activities of Ca^2＋-ATPase and NADKase in tobacco leaves were evaluated under different iron levels with liquid culture method. The results showed that the resistant ability was strengthened, and the symptom was alleviated when treated with Fe 1.68 mg/L in comparison with those of no Fe treatment. Moreover, the Ca^2＋ content was decreased and the CaM content and the activities of Ca^2＋ - ATPase, NADKase in tobacco leaves treated with Fe 1.68 mg/L were increased, compared with those of no Fe treatment. These results indicated that iron nutrient could take part in the regulation of the calcium signaling system, and reduce pathogenic reaction of virus infection. The calcium-calmodulin messenger system between tobacco and TMV could play a role in the intercellular signal transduetion and affect the physiological reaction for plant disease resistance.