水杨酸诱导番茄幼苗抗高温效果

Experiment on the Effect of Inducing Heat Resistance in Tomato Seedlings by Salicylic Acid

用不同浓度水杨酸叶面喷施处理番茄幼苗,通过测定脯氨酸含量、相对电导率、丙二醛含量,筛选出水杨酸诱导番茄幼苗抗高温(40℃)的最佳浓度为60mg·L-1;采用60mg·L-1水杨酸叶面喷施处理番茄幼苗,初步研究了水杨酸诱导番茄幼苗抗高温的机理。喷施水杨酸后,在高温胁迫下能够维持番茄幼苗有较高的膜保护酶SOD、POD、APX的活性,有效降低了番茄幼苗在高温胁迫下活性氧(O2·和H2O2)的产生和积累,减少了膜脂过氧化的产生,从而保护了细胞膜的热稳定性,提高了番茄幼苗抗高温的能力。在提高番茄幼苗抗高温作用中,CAT活性是高温胁迫响应的原因之一,但水杨酸诱导番茄幼苗抗高温可能与CAT的活性无关。

Using salicylic acid of different concentrations to treat tomato （ Lycopersicon esculentum Mill. ） seedling,and through testing Pro,REC and MDA,this study found the best concentration in inducing heat resistance of tomato seedling was 60 mg·L -1 by spraying salicylic acid on its leaves. The mechanism of using salicylic acid to induce heat resistance of tomato seedling was initially studied. After the salicylic acid was sprayed on the leave surface,where high activity of SOD,POD,APX were maintain under high temperature stress, which helped to reduce the producing and accumulating of active oxygen and reduce the oxidative stress, therefore enhance the stabilization of cell membrane and improve the heat resistant ability of tomato seedlings. In the role of improving heat resistance of tomato seedlings, the activity of CAT is one of the causes for high temperature stress, but inducing heat resistance by salicylic acid might have nothing to do with activity of CAT.