水杨酸诱导太子参对叶斑病的抗性

Taizishen(Pseudostellaria heterophylla) Resistance to Leaf Spot disease(Phyllosticta sp.) Induced by Salicylic Acid

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1-7d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,SA5 mmol·L^(-1)诱导处理后能明显增强太子参叶片内POD、PPO酶活性,降低CAT酶活性,其中POD活性比对照增加170%,PPO活性比对照增加293%,CAT活性比对照降低43.3%。6种浓度均能不同程度地诱导太子参对叶斑病产生抗性,以5.0 mmol·L^(-1)水杨酸的诱抗效果最好,达到59.6%,诱抗效果极显著高于其它处理浓度。

To screen the best induced resistance effects of salicylic acid on leaf spot disease of Taizishen（P, heterophylla）, and to study enzyme activity change related to SA disease-resistant, in vitro-regenerated Taizishen plantlets were treated under aseptic conditions with 6 kinds of different concentration of salicylic acid at 0.5-15 mmol.L-1. The activity of related enzymes in leaves 1-7 days thereafter was determined. Disease reaction of the treated planflets was identified with leaf spot（Phyllosticta sp.） spore suspension 7 days after treatment. The results showed that the enzymes activity such as peroxidase, polyphenol oxidase in leaves enhanced, and inhibited catalase activity signiflcautly after inducing with SA at a concentration of 5 mmol.L-1, and POD activity increased by 170%, PPO increased by 293%, and CAT decreased by 43.3% compared with the control. Salieylic acid at concentration of 0.5-15 mmol.L-1 has induced resistance to Taizishen leaf spot disease（Phyllosticta sp.）. Resistance was best induced with salicylic acid at a concentration of 5 mmol/L, whose average effetive percentage was 59.6%, significantly higher than that of other treatment.