Saline-tab water (2.5 L) with 0, 2.5, 5, and 10% saline solution contaminated by P. aeroginosa or S. aureus, was electrolyzed with constant electrical current of 2A or 4A for different time durations (1, 2, 4, 8, and 16min). The electrolysis with 2A-4min showed disinfection effect against P. aeroginosa of 105 CFU/㎖ in all saline concentrations. When the electrical current was raised to 4A, P. aeroginosa of 106 CFU/㎖ was disinfected in 4 min. S. aureus of 105 CFU/㎖ was disinfected with 2A-2 min in all saline concentrations. S. aureus of 106 CFU/㎖ was completely disinfected with 2A-8 min. To compare the effect of constant current electrolysis with that of intermittent current electrolysis, solution contaminated with P. aeroginosa of 106 CFU/㎖ was electrolyzed with several pairs of intermittent current of 2A for 2 min followed by 2min pause. Disinfecting effect of intermittent electrolysis was very similar to the constant current electrolysis without pause in 16 min. The present study demonstrated that the direct electrolyzing process with no septum membrane is a convenient and economic sterilization method.

BC1F7 RILs were cultivated and harvested in field. Two methods were adopted to classify ecotype of the RILs. First method was based on the seed length, width, length/width ratio, phenol reaction of the seed, and response to potassium chlorate of young seedling. Second was the classification using the polymorphism in SSR analysis. The results of UPGMA cluster analysis indicated that 168 RILs were classified into two ecotypes, 32 Japonica and 136 Tongil-type lines when first method was adopted. When second method was adopted, 35 and 99 lines among 134 RILs tested were belonged to Japonica and Tongil-type, respectively. The RILs belonged to same ecotype in both methods was 65.6% in Japonica, 91.9% in Tongil-type and 83.6 % in overall. The parents and BC1F7 RILs showed polymorphism in 20 among 21 RM primers used in SSR analysis. The proportion showing band pattern of each primer corresponded with ecotypes grouped by two methods ranged 29.7 to 99.1%. RM131, RM124, RM567, RM559, and RM348, which are located on chromosome 4, showed high proportion of correspondence over 94%. It was suggested that they would be used as molecular markers for rice ecotype classification. Japonica RILs grouped by two methods showed shorter grain length, no seed response to phenol solution and higher resistance to potassium chlorate solution in seedling stage compared with those of Tongil-type lines.