Figure 7.

Heat stress increases the average cGMP levels in leaves and pollen. Tissues were harvested from plants before or after a 30-min heat stress at 42°C. cGMP concentrations were assayed by competitive binding assay using cGMP-horseradish peroxidase and cGMP-specific antibody. Stress-dependent increases were measured in eight independent experiments for leaf and four independent experiments for pollen. Wilcoxon rank test was used to evaluate significance (asterisk). Means are shown with se.