钙对水杨酸诱导番茄叶片灰霉病抗性及防御酶活性的影响

以番茄‘L402’品种幼苗为试材,经水杨酸(SA)诱导处理后接种灰霉病菌,再进行外源Ca2+、Ca2+螯合剂和Ca2+抑制剂处理,分析Ca2+和SA处理番茄叶片对灰霉病抗性和主要防御酶系活性的变化,探讨Ca2+和SA对番茄诱导抗病性的影响。结果显示:(1)外源SA可显著提高番茄诱导叶和非诱导叶抗灰霉病能力,Ca2+能进一步增强SA诱导的抗病能力;而Ca2+螯合剂EGTA和质膜钙通道抑制剂LaCl3则不同程度地抑制了SA诱导的番茄灰霉病抗性。(2)外源SA能提高番茄诱导叶和非诱导叶中苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、过氧化物酶(POD)活性,外源Ca2+亦进一步增强了SA诱导的上述防御酶活性,但缺钙处理则不同程度降低这些防御酶活性。(3)外源补充Ca2+及不同缺钙处理对SA诱导的过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活性未发现规律性影响。研究表明,钙对SA诱导番茄抗灰霉病性的增强效应,可能与其提高SA诱导番茄叶片中PAL、PPO和POD等防御酶活性有关。

Effects of Calcium on Resistance to Gray Mold and Aactivities of Defensive Eenzymes Induced by Salicylic Acid in Tomato Leaves

Tomato cv.L402 was used as plant material.Resistance to gray mold and activities of defensive enzymes were investigated after sprayed Ca2+ or its antagonist on tomato.The results showed that:(1)Resistance to gray mold were improved significantly for induced and un-induced leaves in tomato treated with SA.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 in induced and un-induced leaves also rose after treated the plant with SA.This response was promoted by exterior Ca2+ and suppressed by the inhibitor of Ca2+ such as EGTA and La3+ in a general way.(3)Activities of CAT and SOD induced by SA were not regulated by Ca2+ or inhibitor of Ca2+.Consequently,modulating of calcium on the induced resistance to tomato gray mold by SA may has relations with the activities of defensive enzymes such as PAL,PPO and POD in tomato leaves.