Figure 4: Dissected embryos of atabcg30, atabcg40 and atabcg30 atabcg40 are less sensitive than the wild type (WT) to endosperm-dependent or exogenous ABA-dependent germination repression.

(a–c) Seed coat bedding assay, using embryos dissected from WT (Col-0) or atabcg mutant seeds placed on a layer of seed coat beddings (endosperm and testa) dissected from dormant Cvi seeds (Cvi (D)). (b,c) Data are means±s.e.m. of n=105–109 obtained from three independent experiments. Each experiment was performed in duplicate. Each replicate (one SCB) consisted of 20 embryos (N=3, n=2 × 20 embryos). (d–f) Embryos dissected from WT (Col-0) and atabcg mutant seeds placed on ½ MS medium supplemented with 0.1 μM ABA. The angle between the cotyledon and radicle (b,e) and the radicle length (c,f) were measured as indicators of embryonic growth for each genotype of embryo. (e,f) Data are means±s.e.m. of n=108 obtained from three independent experiments. Each experiment was performed in triplicate. Each replicate consisted of 12 embryos (N=3, n=3 × 12 embryos). In a, photographs were taken at 4 h (top) and 96 h (bottom) after imbibition. In d, photographs were taken 4 h (top) and 166 h (bottom) after imbibition. Scale bar, 1 mm. (a,d) A representative result out of three independent experiments is shown (six (a) or nine (d) different samples). In all experiments, similar results were obtained.