Chemical complementation of
mutant phenotype by ABA-treatment. Leaves of seven-day-old barley plants from cultivar Steptoe or mutant Az34 were sprayed either with abscisic acid (20 μM) or mock solution. Inoculation was done one hour later with M. oryzae isolate TH6772 at a spore density of 200,000 conidia mL−1. Pictures were taken seven days post inoculation. Quantification of disease severity was done by counting blast lesions. Bars represent means and standard deviations of ten leaves and significant differences (t-test, p ≤ 0.05) are indicated with an asterisk. The experiment was repeated once with a similar result.