he inocula of two bacterial pathogens, B. glumae KACC 10359 and X. oryzae pv. oryzae KACC 10208 were prepared using the cell suspension after cultivation in R2A and YGC media, respectively, at 28°C for 24 h on a rotary shaker (160 rpm). The culture broth of B. glumae was centrifuged (5,000 g, 10 min) and cell pellets were suspended in buffer solution (10 mM MgSO4) adjusted to 6×107 cfu/ml. A pin-prick bioassay was conducted for inoculation of the suspension of B. glumae. A bundle of 3–4 pins/needles was dipped into the suspension and then leaves were teased with the needles of bundle. Disease severity was evaluated 5 days after inoculation of the pathogen to the 5-week-old rice seedlings using a 0–3 disease rating scales: 0 = symptomless, 1 = slight infection, few small lesions, 2 = coalesced lesions to browning all over, and 3 = no description available (Cottyn et al., 1996). In case of bacterial blight, the suspension of X. oryzae pv. oryzae was prepared following the same procedure of B. glumae and concentration was adjusted to 1.2×107 cfu/ml. A clipping bioassay for bacterial blight was conducted using scissors that were dipped into the suspension and then used to cut the upper leaves. Disease severity was determined 7 days after inoculation according to a 1–9 scale (Misra et al., 1994). Disease reduction was calculated following the formula: [(disease severity of the control – disease severity of a treatment) / disease severity of the control] × 100%.