FIGURE 5.

Exogenous GA₃ effectively reverses the GA-deficiency phenotype. (A) Ten-day-old seedlings germinated and grown in Yoshida’s culture solution containing 10 μM GA₃ or no GA₃. Bar = 5 cm; (B) GA₃ treatment. Ten-day-old seedlings were sprayed with 100 μM GA₃ daily for 6 days. Bar = 5 cm. (C) GA₃ treatment. Four-week-old seedlings were sprayed with 100 μM GA₃ daily for 10 days. Bar = 10 cm. (D) Relative shoot length was measured on wild-type plants and three JcDREB2-overexpressing lines after 10 days of growth on Yoshida’s culture solution containing 10 μM GA₃ or no GA₃. (E) Elongation growth of 10-day-old JcDREB2-overexpressing and wild-type seedlings treated with GA₃. Plant shoot length was measured 6 days after GA₃ treatment. (F) Elongation growth of 4-week-old JcDREB2-overexpressing and wild-type seedlings treated with GA₃. Plant shoot length was measured 10 days after GA₃ treatment. (G) Elongation ratio (+GA₃/-GA₃) of 10-day-old seedlings germinated and grown in Yoshida’s culture solution. (H) Elongation ratio (+GA₃/-GA₃) of 10-day-old seedlings grown with GA₃ or without GA₃ for 6 days. (I) Elongation ratio (+GA₃/-GA₃) of 4-week-old JcDREB2-overexpressing and wild-type seedlings grown with GA₃ or without GA₃ for 10 days. The experiment included three biological replicates. Values represent (D–I) means of n = 15 ± SD from three independent experiments and different letters above the columns indicate significant differences from the corresponding WT at the p < 0.01 level.