Pythium myriotylum is a destructive soil-borne phytopathogen, causing yield losses in ginger and many other crops. Environmental and regulatory concerns drive the need to find biological alternatives to conventional pesticides used to manage P. myriotylum. Trans-cinnamic acid (TCA) alone, and fermentation broth from strains of symbiotic bacteria of eight species of entomopathogenic nematodes alone, and in combination with TCA, were tested for their effect on zoospore germination and mycelial growth of P. myriotylum. TCA significantly inhibited mycelial growth. Fermentation broths from seven of the eight strains of symbiotic bacteria directly inhibited mycelial growth, especially those isolated from Steinernema feltiae (strain SN) and S. riobrave (strain 7–12). Moreover, adding TCA significantly increased the inhibitory effect on mycelial growth of the fermentation broths of seven of the strains tested. All bacteria fermentation broths showed inhibitory effects on zoospore germination. However, TCA alone was not inhibitory to zoospore germination but was inhibitory to mycelial growth. Antimicrobial effects on mycelial growth and zoospore germination were proportional to the concentration of symbiotic bacteria isolated from S. feltiae (strain SN). These results show that TCA and symbiotic bacteria of entomopathogenic nematodes may have potential to provide biorational control of P. myriotylum.

腐霉腐霉是一种破坏性的土壤传播植物病原体，会导致生姜和许多其他农作物的单产下降。环境和法规方面的考虑驱使寻找替代传统农药来管理鼠疫的生物替代品的需求。测试了单独的肉桂酸（TCA）和仅来自8种昆虫病原线虫的共生细菌菌株的发酵液，并与TCA结合使用对肉桂孢子菌的游动孢子萌发和菌丝体生长的影响。三氯乙酸显着抑制菌丝生长。八种共生细菌菌株中的七种的发酵液直接抑制菌丝体的生长，特别是分离自Steinernema thinkiae的菌丝体（SN菌株）和S. riobrave（7-12菌株）。此外，添加TCA显着增加了对所测试的七个菌株的发酵液的菌丝生长的抑制作用。所有细菌发酵液均对游动孢子萌发具有抑制作用。但是，单独的TCA不能抑制游动孢子的萌发，但可以抑制菌丝体的生长。对菌丝体生长和游动孢子萌发的抗微生物作用与从毡状链球菌（SN菌株）分离的共生细菌的浓度成正比。这些结果表明，TCA和昆虫病原线虫的共生细菌可能具有提供生物合理控制鼠疫假单胞菌的潜力。