3,4,5-三羟基苯甲酸甲酯防治番茄青枯病的物理作用方式及其对番茄根系次生代谢物质的影响

Physical modes of action of methyl gallate for controlling tomato bacterial wilt and its effect on secondary metabolites of tomato roots

通过生物学方法测定3,4,5-三羟基苯甲酸甲酯(MG)防治番茄青枯病的物理作用方式,采用气相色谱-质谱联用方法分析该化合物对番茄根系组织次生代谢物质的影响。结果表明,3,4,5-三羟基苯甲酸甲酯对番茄青枯病有较好的预防作用,持效期较长,施药15d后接种青枯病菌,防效仍达52.12%;该化合物可快速扩散到番茄根系组织内,但其向植株顶部和基部的输导作用弱,对番茄青枯病的治疗效果差。番茄根系中共鉴定出36种次生代谢物质,与对照相比,3,4,5-三羟基苯甲酸甲酯处理对番茄根系次生代谢产物的组成和相对含量有明显影响,其中与抑菌活性相关的物质有香叶醇、豆甾醇、β-谷甾醇和木栓醇等4种,前3种物质在3,4,5-三羟基苯甲酸甲酯处理植株体内表现为含量显著升高,木栓醇则为苗期用3,4,5-三羟基苯甲酸甲酯处理后番茄根系新增的化合物。

The physical modes of action of methyl gallate（MG）for controlling tomato bacterial wilt were determined by biological method,and its effect on secondary metabolites of tomato roots was determined by gas chromatography-mass spectrometry（GC-MS）method.The results showed that methyl gallate could effectively protect tomato from tomato bacterial wilt with a long lasting period.When methyl gallate was applied 15 d before the pathogen was inoculated,the control efficacy could reach 52.12%.Methyl gallate could diffuse quickly towards tomato root tissues;however,the compound was difficult to translocate from bottom to top or reversed.A total of 36 secondary metabolites produced from tomato roots were identified.Compared with the contrast,the categories and relative contents of root secondary metabolites under the MG treatment were obviously changed.Four of them were relevant to antimicrobial activity,which were geraniol,stigmasterol,β-sitosterol and friedelinol,and the first three were significantly increased and friedelinol was a new compound in seedling roots under the MG treatment.