Figure 3

Response of nec1 to non-host pathogen Pseudomonas syringae pv. tomato applied at low and high inoculum densities. Panel A. Growth of Pseudomonas syringae pv. tomato in nec1 and parental cv. Parkland was monitored immediately and 3 days after vacuum infiltration with Pst applied at inoculum densities of 8 × 10⁴ or 6 × 10⁷ cfu ml^-1. For mock inoculation plants were infiltrated with 10 mM MgCl₂. Infection was expressed as number of colony forming units (cfu) per gram of fresh leaves (FW). Due to the high between-experiment variation, results of one representative experiment out of four independent experiments are shown. Error bars represent standard deviation. At high inoculum density (6 × 10⁷cfu ml^-1) bacterial cfu number in nec1 at the day 3 was significantly (p < 0.01, Student's t-test) lower than in wt. Panel B. Progression of cell death in nec1 and Parkland after infection with Pseudomonas syringae pv. tomato in the experiment shown in panel A. nec1 mutation showed increased electrolyte leakage in barley inoculated with non-host bacteria Pst at 6 × 10⁷ cfu ml^-1. Measurements of electrolyte leakage were taken every two hours during 24 hour period and at 48 hours after inoculation. Error bars represent standard deviation.