Figure 2.

Capacity of GA₃ and GA₄ to Induce Dormancy Release/Bud Burst and to Initiate Development.

(A) Bud burst after incubation in 0.1 to 100 μM GA₄ and GA₃. With higher concentrations of GA₄, most buds show canonical or true bud burst (i.e., elongating internodes) and de novo formation of leaves (inset) at around 10 d. Low concentrations of GA₃ (0.1 to 10 μM) could induce leaf protrusion and unfolding, which was not accompanied by formation of leaves and stem elongation (inset).

(B) to (E) Abscission events induced by 100 μM GA₃. Within 1 to 2 weeks after the initial application of GA₃ to dormant buds (B), cell proliferation was visible at the base of the bud (C), producing a callus-like cell mass (detail in [D]), along which buds often abscised (E).

Bars = 5 mm in (A) to (C) and (E), and 1 mm in (D).