Fig 1.
Effect of DPI on barley seed germination.
Seeds were incubated in ○ DW, ■ 10 μM, ▲ 100 μM, ● 1 mM, or ◆ 5 mM DPI for 5 days. Values are means ± SD of five replicates.
Fig 2.
Localization of superoxide anion, hydrogen peroxide, and NADPH oxidase mRNA induced after imbibition in barley seeds.
(A) Distilled water; (B) NBT; (C) DAB (each for 24 h). (D—G) Expression of NADPH oxidase mRNA. Barley seeds imbibed for 24 or 48 h were bisected, and the cut surfaces were printed onto two membranes: (D, F) hybridized with antisense probe for NADPH oxidase; (E, G) hybridized with the corresponding sense probe as a control for non-specific binding. Emb, embryo; Endo, endosperm; Aleu, aleurone layer.
Table 1.
Superoxide and hydrogen peroxide contents in embryos of DPI-treated barley seeds.
Fig 3.
Gibberellin contents in barley seed embryos treated with DPI.
Embryos were removed from barley seeds that had been treated with distilled water or 1 mM DPI for (A) 18 and (B) 30 h. Values are means ± SD of five replicates.
Fig 4.
Expression of gibberellin biosynthesis—related genes in barley seed embryos treated with DPI.
Embryos were removed from barley seeds that had been treated with ○ distilled water as a control or ● 1 mM DPI. Values are means ± SD of five replicates.
Table 2.
ABA content in embryos of DPI-treated barley seeds.
Fig 5.
Expression of abscisic acid metabolism—related genes in barley seed embryos treated with DPI.
Embryos were removed from barley seeds that had been treated with distilled water or 1 mM DPI. ○ Control, ● DPI treatment. Values are means ± SD of five replicates.
Fig 6.
NADPH oxidase activity and ROS content of barley seed embryos treated with ABA.
Embryos were removed from barley seeds that had been treated with distilled water or 50 μM ABA for 24 h. (A) O2− content; (B) H2O2 content. (**P < 0.05, Student’s test, n = 5).
Fig 7.
Expression of barley NADPH oxidase mRNAs in barley seed embryos treated with ABA.
Embryos were removed from barley seeds that had been treated with distilled water or 50 μM ABA for 24 h. (**P < 0.05, Student’s test, n = 5).
Table 3.
Superoxide and hydrogen peroxide contents in DPI-treated embryoless half-seeds.
Fig 8.
Induction of α-amylase in embryoless half-seeds treated with distilled water, 1 μM GA, or 1 μM GA + 1 mM DPI for (a) 12, (b) 24, (c) 36, and (d) 48 h.
Bar with different letters differ significantly (P < 0.05, Tukey’s test, n = 3).
Fig 9.
Gene expression and activity of NADPH oxidases in embryoless half-seeds treated with distilled water, 1 μM GA, or 1 μM GA + 50 μM ABA for 24 h.
Bar with different letters differ significantly (P < 0.05, Tukey’s test, n = 3).
Fig 10.
Effect of calcium ions on NADPH oxidase activity in embryoless half-seeds treated with distilled water, 1 μM GA, 1 μM GA + 5 or 10 mM EGTA, 1 μM GA + 5 or 10 mM LaCl3, or 1 μM GA + 50 mM calmidazolium for 24 h.
Bar with different letters differ significantly (P < 0.05, Tukey’s test, n = 5).
Fig 11.
Role of NADPH oxidases in barley seed germination.
Black lines, our results; dashed lines, previous reports.