钙素对SA诱导番茄幼苗抗灰霉病的调控作用

The Effect of Calcium on Regulation of SA-induced Resistance to Botrytis cinerea in Tomato

为探索钙对水杨酸(SA)诱导番茄(Solanum lycopersicum)幼苗抗灰霉病的作用,采用‘L402’番茄品种,通过分别喷施8mmol.L-1CaCl2和5mmol.L-1EGTA后再喷施2mmol.L-1SA,3d后接种灰霉病菌孢子的方法,研究了不同处理对番茄幼苗灰霉病病情指数、活性氧积累、主要防御酶活性及其基因表达的影响。结果表明:接种灰霉病菌孢子5d后,SA处理的番茄幼苗病情指数比对照降低37.27%,Ca+SA处理较SA处理进一步降低18%;接种1d和2d后,叶片中产生速率和H2O2含量分别出现应激高峰,且处理间存在差异,与对照相比Ca+SA处理分别提高33.05%和29.31%,EGTA+SA处理分别降低32.62%和46.34%;叶片中抗病相关酶活性和基因表达在接种病菌后也出现应激高峰,其中Ca+SA处理显著提高了PAL、几丁质酶、β-1,3-葡聚糖酶活性,EGTA处理及EGTA+SA处理显著降低了PAL、几丁质酶、β-1,3-葡聚糖酶活性。上述结果表明,Ca2+在SA诱导番茄抗灰霉病中具有正调控作用,而且这种作用与PAL、几丁质酶、β-1,3-葡聚糖酶活性及其基因表达密切相关。

In order to explore the effect of calcium on the SA-induced resistance to Botrytis cinerea in tomato（Solanum lycopersicum）.Tomato Botrytis cinerea susceptible strain＇L402＇was pretreated with foliar spraying 8 mmol·L1 CaCl2 and 5 mmol·L-1EGTA,respectively.Then followed by application of exogenous 2 mmol·L-1 SA,3 d before B.cinerea infection.The disease index,ROS accumulation,variations of the activities of main resistance enzymes and their gene expression were analyzed.The results show that the disease index is significantly reduced by 37.27%compared to control in SA treatment 5 d after B.cinerea infection;While in Ca＋SA treatment,the disease index reduced by 18%compared to SA treatment.Theproduction rate and H2O2 content reached the highest level at 1 d and 2 d,respectively,there is difference among treatments：production rate ofand H2O2 content in tomatoes treated by Ca＋ SA are 33.05%and 29.31%higher than contro（lH2O）,however,under EGTA＋SA treatment significantly reduced by 32.62%and 46.34%,respectively.The peak of disease defense-related enzymes activity and gene expression also exist,difference obtained among treatments：PAL,chintase andβ-1,3-glucancse treated by Ca＋SA are significantly higher than control,whereas EGTA and EGTA＋SA significantly suppress PAL,chitinase,β-1,3-glucanase activity.These results indicate that Ca2 ＋plays a positive regulatory role in the SA-induced resistance to Botrytis cinerea in tomato,which is closely related to the PAL,chitinase,β-1,3-glucanase activity and gene expression.