Comparative steady-state analysis of soluble metabolites in stamens of wild type and jai1-1. Soluble metabolites were extracted from stamens of three developmental stages and analyzed by non-targeted metabolite profiling. Levels of metabolites were compared between wild type and jai1-1 in each developmental stage. (a) Venn diagram showing the number of metabolites accumulating in significantly different amounts in wild type and jai1-1 stamens (P ≤0.05, n = 6). Note that the highest number of differentially occurring metabolites was found in stage 3. (b) Classification of differentially occurring metabolites according to their chemical nature. Numbers in bold indicate how many metabolites occurred in different amounts in total in the respective developmental stage, whereas the small numbers show how many metabolites of them exhibited increased levels in wild type (dark red) or jai1-1 (dark blue). Light red and light blue colors mark the overall tendency of differential accumulation in each developmental stage/substance class (red higher in wild type, blue higher in jai1-1). (c) Grouping of max-normalized metabolites according to their kinetics during development. The mean (± SD) of all metabolites belonging to the respective group is shown, for details of differentially occurring metabolites see Figure S3 in Additional file 2. The following criteria were applied for building groups: higher accumulation according to the Venn diagram in at least one developmental stage of wild type (I-III) or jai1-1 (IV-VI), and kinetics of metabolite levels (I, IV: increasing during development; II, V: decreasing during development; III, VI: peaking at stage 3). The Arabic numbers show the number of metabolites in each group. Note that most metabolites show an accumulation during stamen development. SD, standard deviation.