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本文明确了Ｐｙｔｈｉｕｍａｐｈａｎｉｄｅｒｍａｔｕｍ主要靠生产以ＰＧ（多聚半乳糖醛酸酶）为主的一系列细胞壁降解酶的协调作用侵染黄瓜幼苗。植株胚轴细胞壁随苗龄增加，果胶物质增加最明显。病菌可在健胚轴及其细胞壁上培养产生果胶酶，其中细胞壁对ＰＧ的诱导作用比胚轴明显。随病菌致病力增强或病菌果胶酶浓度加大，胚轴的浸解和释放还原糖愈加明显。健株外渗物中虽也含有细胞壁降解酶，但比病菌的产生量少，活性低。病菌在寄生体内产生的细胞壁降解酶总酶活性，尤其是ＰＧ总酶活性与病菌致病力关系最为密切。这类细胞壁降解酶易受培养基成分和酸度的影响。经染色、显微及超微观察证实了该菌侵入黄瓜苗的机制是以酶解作用为主。
This paper made clear that Pythiumaphanidermatum infects cucumber seedlings mainly through the coordination of a series of cell wall degrading enzymes that produce mainly PG (polygalacturonase). Plant hypocotyl cell wall increased with age, the most obvious increase in pectin substances. Pathogen can produce pectinase in the hypocotyl and its cell wall, and the induction of PG by cell wall is more obvious than the hypocotyl. With the increased pathogenic bacteria or bacteria pectinase concentration increased, hypocotyl release and release of reducing sugars become more apparent. Although the plant extravasation also contains cell wall degrading enzymes, but less than the production of bacteria, low activity. The total enzyme activity of cell wall degrading enzymes produced by pathogens in the parasites, especially PG total enzyme activity, is most closely related to the pathogenicity of the bacteria. Such cell wall degrading enzymes are susceptible to media composition and acidity. The staining, microscopic and ultrasmall observation confirmed that the bacteria invaded the mechanism of cucumber seedlings by enzymolysis.