Fig. 5.

Overexpression of GhMKK5 conferred on transgenic plants enhanced resistance to bacterial pathogens. (A) Northern blot analysis of GhMKK5 expression in T₁ OE and Vec plants. (B) Signs of disease of the detached leaves from OE (#2) and Vec plants inoculated with 20 μl of a suspension (OD₆₀₀=0.6–0.8) of R. solanacearum. The inoculated leaves were maintained under greenhouse conditions with 80% relative humidity for 1 week, and photographs taken at day 4 are presented. (C) Bacterial growth in the leaves of Vec and #2 plants at different time points after infiltration with R. solanacearum. Data are the means ±SE of three independent experiments (n=6). Asterisks (*) above lines indicate significant differences (P < 0.05) according to Duncan’s multiple range test. (D) Disease signs and survival rates of the OE (#2) and Vec plants inoculated with R. solanacearum using the trickle irrigation method. Data are the means ±SE of three independent experiments (n ≥ 30). Different letters above the columns indicate significant differences (P < 0.05) according to Duncan’s multiple range test. (E) RT-PCR analysis of the expression of PR genes in OE (#2, #4, and #5) and Vec plants under normal and R. solanacearum inoculation conditions. OE, overexpression; Vec, vector control; #2, #4, #5, particular overexpressing lines.