钙对茉莉酸甲酯诱导番茄抗灰霉病及防御酶活性的调控作用

以番茄品种L402幼苗为试材，通过外源施钙和缺钙处理，探讨钙对茉莉酸甲酯（MeJA）诱导番茄抗灰霉病的作用及其生理机制。结果表明：（1）外源MeJA显著诱导番茄抗灰霉病|外源钙离子进一步增强MeJA诱导的抗病程度|而钙螯合剂EGTA和质膜钙通道抑制剂LaCl3则不同程度抑制MeJA诱导番茄的抗病性。（2）MeJA单独处理后2～5 d内PAL、PPO和POD活性显著高于对照，外源钙离子进一步增强MeJA诱导的上述防御酶活性，两种缺钙处理则不同程度降低防御酶活性。（3）外源施钙及不同缺钙处理，对MeJA诱导的CAT和SOD活性没有规律性影响。由此认为，钙增强MeJA诱导番茄抗灰霉病的程度，可能与其对MeJA诱导番茄叶片中PAL、PPO和POD等防御酶活性的调控有关。

Adjusting and Controlling Effect of Calcium on Resistance to Tomato Gray Mold and Defensive Enzymes Activity Induced by Methyl Jasmonate

Taking tomato（Lycopersicon esculentum Mill.）variety‘L402’seedling as material, we investigated the effect and physiological mechanism of calcium to methyl jasmonate（MeJA）inducing tomato resistance to gray mold after treated the tomato leaves with MeJA，Ca2+ or inhibitor of Ca2+．The results showed that（1）Resistance to tomato gray mold was improved significantly after the plant treated with MeJA．Induced resistance was farther enhanced by Ca2+ but restrained badly by chelator as EGTA or the plasmalemma Ca2+ channel blocker as LaCl3．（2）Activities of PAL，PPO and POD also rose after the plant treated with MeJA．The response was generally promoted by exterior Ca2+ and suppressed by the inhibitor of Ca2+ such as EGTA and LaCl3．（3）However，activities of CAT and SOD induced by MeJA were not regulated by Ca2+ or inhibitor of Ca2+．Consequently，modulating of calcium on the induced resistance to tomato gray mold by MeJA may have relations with activities of defensive enzymes such as PAL，PPO and POD in tomato leaves.