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本文明确了间苯三酚、邻苯二酚、香草醛对黄瓜苗期猝倒病菌瓜果腐霉菌（Ｐｙｔｈｉｕｍａｐｈａｎｉｄｅｒｍａ－ｔｕｍ）生长及其细胞壁降解酶体外合成和活性的影响。结果表明：３种酚类物质中香草醛抑制病菌生长比较明显，随着香草醛浓度提高，病菌菌落直径下降。３种酚类物质均能明显抑制病菌４种果胶酶（ＰＧ，ＰＭＧ，ＰＧＴＥ，ＰＭＴＥ）的合成和活性，３种酚类物质抑制作用因果胶酶种类而异。邻苯二酚和香草醛对ＰＧ合成抑制比较明显。间苯三酚和邻苯二酚在各浓度下均完全抑制ＰＭＧ合成。酚含量２０ｐｐｍ以上时，香草醛完全抑制了ＰＧＴＥ和ＰＭＴＥ合成，间苯三酚完全抑制了ＰＭＴＥ合成。香草醛对ＰＧ、ＰＭＧ和Ｃｘ活性均有明显抑制作用。随苗龄增加过氧化物酶活性升高，木质化程度加强，寄主抗果胶酶降解能力也相应增加。寄主细胞壁降解中释放的半乳糖醛酸有刺激过氧化物酶活性的作用，这可能属于一种寄主自卫反应
In this paper, the effects of phloroglucinol, catechol and vanillin on the growth and cell wall degrading enzyme activity of Pythium deodarum in cucumber seedlings were studied. The results showed that vanillin inhibited the growth of pathogenic bacteria in three kinds of phenolic compounds. With the increase of vanillin concentration, the diameter of bacteria decreased. The three kinds of phenolic compounds could significantly inhibit the synthesis and activity of four pectinases (PG, PMG, PGTE and PMTE). The inhibitory effects of the three phenolic compounds were different due to pectinase types. Catechol and vanillin inhibit PG synthesis more obvious. Phloroglucinol and catechol completely inhibited PMG synthesis at all concentrations. Vanillin completely inhibits the synthesis of PGTE and PMTE when the phenol content is above 20ppm, and phloroglucinol completely inhibits PMTE synthesis. Vanillin significantly inhibited the activity of PG, PMG and Cx. With the increase of seedling age increased peroxidase activity, increased degree of lignification, the host resistance to pectinase degradation also increased accordingly. The release of galacturonic acid during host cell wall degradation has the effect of stimulating peroxidase activity, which may belong to a host self-defense reaction