Pollen release from anthers of wild type, jai1-1 and mutants affected in ET-signaling. Dissected anthers of the developmental stage 4s (a), 5 (b) and 6 (c) of wild type (WT), jai1-1, never ripe (NR), epinastic (epi) and the double mutant jai1-1 NR were shaken in PBS and released pollen were counted. The overproduction of ET in epi resulted in similar premature pollen release at stage 4 as detectable for jai1-1, whereas pollen release in NR and jai1-1 NR is similar to WT. Note that the absolute numbers of released pollen are less in jai1-1-based genotypes due to the high number of aborted pollen (see Figure 3). Mean values + SD are shown (n ≥13). Different letters designate statistically different values (ANOVA with Tukey’s HSD test; P ≤0.01). ANOVA, analysis of variance; ET, ethylene; HSD, honest significant difference; SD, standard deviation.