Plant Journal 23: 215-221 (2000)

Sense transformation reveals a novel role for class I ß-1,3-glucanase in tobacco seed germination

ABA-inducible ßGLU I overexpression promotes ABA-delayed endosperm rupture of afterripened seed

Figure 1. The effect of 10 µM ABA on the time course of endosperm rupture and ßGLU accumulation in afterripened S1 seeds of independent sense ßGLU I (TKSG7) and empty-vector (TCIB1) transformants. (a) and (c) The incidence of endosperm rupture expressed as percent of 100-150 seeds scored with time after the start of imbibition in continuous light without (a) and with (c) 10 µM ABA added. Segregating seed populations of lines carrying one (TKSG7-43), two (TKSG7-34 and TKSG7-42), and three or more (TKSG7-10) transgene loci were used. Means of two replicates from one experiment are presented. Similar results were obtained in a second experiment. Error bars indicate the largest ± SE value. (b) and (d) The ßGLU enzyme activities of imbibed TKSG7 and TCIB1 seed populations without (b) and with (d) 10 µM ABA. Error bars (b) indicate the largest ± SE values of lines TKSG7-10, TKSG7-34, and TKSG7-42 (upper corner), and of lines TCIB1 and TKSG7-43 (lower corner). Error bars (d) indicate individual ± SE values (TKSG7 lines) and the largest ± SE value (TCIB1 lines). Note the difference in scales of (b) and (d).
© Leubner-Metzger and Meins, Plant J 23: 215-221 (2000)