Figure 5.

Alleviation of Arabidopsis primary seed dormancy by SLs and their analogs shows stereoisomeric specificity. Primary dormant Ler seed was sown on water-agar (1% [w/v] phytagel supplemented with 1.5 mm MgCl₂ as a gelling agent) containing either 0.1% (v/v) acetone (mock) or 1 µm each compound as indicated. A, Germination responses to natural deoxySLs and their enantiomers. B, Germination responses to the four stereoisomers of GR24. C, Germination responses to the two stereoisomers of CN-debranone. Values are means ± ses of three independent samples of 100 seeds. Plates were incubated at 28°C under constant light, and germination was scored daily. Treatments with significantly different germination levels after 168 h are indicated by different lowercase letters (P < 0.01, ANOVA). The data for mock-treated and KAR₁-treated controls are the same in each graph. CN-deb, CN-debranone.