水杨酸诱导太子参对叶斑病的抗性

为探讨水杨酸SA对太子参叶斑病的诱抗效果以及有关酶活性的变化与SA抗病作用的可能联系,在离体培养条件下,运用水杨酸0.5～15 mmol·L-1 6种不同浓度处理太子参组培苗,在1～7 d内测定叶片相关酶活性的变化,诱导培养7d后,用太子参叶斑病孢子悬浮液对组培苗进行抗性鉴定.结果表明,SA 5 mmol·L-1诱导处...

Taizishen's Resistance to Leaf Spot Disease Induced by Salicylic Acid

Salicylic acid(SA) was applied on Taizishen(Pseudostellaria heterophylla) to induce the plant’s resistance to the leaf spot disease.Enzyme activities relating to the disease-resistance were investigated.In vitro-regenerated Taizishen plantlets were treated under aseptic conditions with 6 different concentrations of SA,0.5-15 mmol·L-1,to determine the optimum SA induction level.Activities of various enzymes in the leaves were determined within 1-7 days after SA treatment.The disease-resistance of the treated plantlets was observed with the application of a water suspension of the leaf spot spores,7 days after the treatment.The results showed that(a) the activity of the enzymes,such as peroxidase and polyphenol oxidase,in the leaves was enhanced by SA treatment;(b) the catalase activity was significantly inhibited after induction by SA at a concentration of 5 mmol·L-1;and(c) POD activity increased by 170%,PPO increased by 293%,and CAT decreased by 43.3%,as compared to the control.SA concentration in the range of 0.5-15 mmol·L-1 appeared to be capable of inducing the disease-resistance in Taizishen.The best result seemed to be at the concentration of 5 mmol·L-1 SA,as the average effective rate was 59.6%,which was significantly higher than those achieved by the other treatments.