Figure 2
Effect of ice-nucleating bacteria and frost treatment on percentage of leaves inoculated with Z. tritici showing pycnidia at various time points after infection (A) and final pycnidial density (B). Wheat leaves were inoculated with MgCl2 only (control), or with either non ice-nucleating bacteria (INA−) or ice-nucleating bacteria (INA+) in MgCl2. Three to five leaves in each of 24 pots (total 72–120 leaves) were used in each treatment. After 24 h, 12 randomly selected pots from each treatment (36–60 leaves) were exposed to − 2 °C for 2 min. All plants were then inoculated with Z. tritici blastospores at 105 cfu/mL and infected plants maintained as normal. Leaves were inspected and numbers of leaves showing pycnidia recorded every 3–4 days from 7 to 21 dpi (A). At 28 dpi, leaves were harvested and pycnidia enumerated (B). Values are means of two independent experiments and error bars show standard error. Letters above bars indicate significant (α = 0.05) differences between treatments (ANOVAs with Tukey’s simultaneous comparisons) and only apply within time points in (A). No letters are shown where the ANOVA result was non-significant (A: 7, 10, 14 and 28 dpi, and B).
