In this report, an effect of FFC-ceramic (FFC-Japan Co. Ltd., Tsu) water on the process of infection by a pea fungal pathogen, Mycosphaerella pinodes was investigated. Energy dispersive X-ray analysis showed that both of the FFC-ceramic water and a common ceramic water contained mainly Ca and S elements, of which the relative atomic percentages were 53~56% and 44~45%, respectively. Lesion formation by pycnospores of M. pinodes on pea leaves was inhibited severely by the application with both ceramic waters at the 1/2~1/6 concentration of saturated solution. Cytological observation under microscope showed that germination, germ-tube elongation and penetration were severely inhibited by these ceramic waters. However, such inhibitory effect of FFC-ceramic water was superior to that of the common ceramic water. On ethanol-killed pea epidermal tissues, both FFC-ceramic water and the common ceramic water blocked the germination, germ-tube elongation and penetration by the pathogen, indicating
the direct effect of both ceramic waters on the fungus. In this case, the inhibiting effect of FFC ceramic water was more intensive than the common ceramic water. CaSO(4) at a 1/2~1/4 concentration of saturated solution blocked penetration by the fungus on the killed epidermis of onion bulb but scarcely affected germination and germ-tube elongation. Based on these results, we discussed the role of FFC-ceramic water in disease tolerance of plants and its availability for cultivation.