Figure 2

Transient transformation efficiency in hybrid aspen leaves. (A) Effect of infiltration medium on transient transformation. Overnight culture of Agrobacterium was re-suspended in individual infiltration medium containing 200 μM Acetosyringon and 0.0075% Silwet L-77 (final OD₆₀₀ = 0.5). The GFP signals were observed after three days of the transformation. Transformation efficiency was calculated by counting GFP positive cells in a 1.5-mm² leaf area. Values are means ± SE (n = 330). Asterisk indicates a statistically significant difference based on a Student’s t-test (P < 0.01). (B) Effect of Silwet L-77 concentration on transient transformation. Overnight culture of Agrobacterium was re-suspended in the medium [0.5 × MS, 5 mM MES-KOH (pH 5.6) and 200 μM Acetosyringon] (final OD₆₀₀ = 0.5). Appropriate Silwet L-77 was added to the solution. Values are means ± SE (n = 350). Means with different letters are different according to Tukey’s HSD test (P < 0.05). (C) Effect of bacteria density on transient transformation. Overnight culture of Agrobacterium was re-suspended in the medium [0.5 × MS, 5 mM MES-KOH (pH 5.6), 200 μM Acetosyringon and 0.015% Silwet L-77]. The final OD₆₀₀ was adjusted to 0.5, 1.0, and 2.0. Values are means ± SE (n = 480). Means with different letters are different according to Tukey’s HSD test (P < 0.05). The experiments shown are from two or three experiments each of which included three biological repeats. For each biological repeat, 40 to 60 sectors were measured.