Figure 5

Infection phenotype of M. oryzae on barley mutant Az34 which is impaired in ABA-biosynthesis. Disease symptoms on primary leaves of barley cultivar Steptoe and the mutant Az34, inoculated either with M. oryzae isolate TH6772 (200,000 conidia mL⁻¹) or isolate BR32 (100,000 conidia mL⁻¹), are depicted at seven and six days after inoculation, respectively (A). Blast lesions were counted for each genotype and treatment. Means and standard deviations calculated for eight leaves are shown (B). Leaves harvested at 72 h p.i. were analysed by microscopy (C). Categorisation of plant-fungus interaction sites was done according to Figure 1. Bars represent means and standard deviations for four leaves with at least 100 interaction sites inspected per leaf. Significant differences between Steptoe and mutant plants observed in (B) and (C) were determined using t-test (p ≤ 0.05) and marked with asterisks. For (C) the significance was tested separately for each category. The experiment was repeated twice with similar results.