Figure 2

Effect of phytohormone application on the infection of barley with M. oryzae . Primary leaves of barley cultivar Ingrid were sprayed with the following solutions seven days after sawing: sodium salicylate (SA, 0.1 mM), 1-aminocyclopropane-1-carboxylic acid (ACC, 20 μM), indole-3-acetic acid (IAA, 20 μM), gibberellic acid (GA₃, 20 μM), abscisic acid (ABA, 20 μM) or mock solution, respectively. One hour after treatment the plants were inoculated with conidia of M. oryzae isolate TH6772 (200,000 conidia mL⁻¹). Representative leaves of each treatment seven days after inoculation are depicted in (A). Individual plant-fungus interaction sites were inspected microscopically on leaves harvested at 72 h p.i. (B) and assigned to categories as depicted in Figure 1. Bars represent means and standard deviations of four leaves with at least 100 interaction sites evaluated per leaf. Significant differences were determined for each category using One Way ANOVA (p ≤ 0.05) and marked by different letters. The experiment was repeated once with a similar result.