Figure 3. Effect of sonication treatment on P. japonicum plants.

A Transformation efficiency with A. rhizogenes strain ATCC15834 and sonication (0, 10, 50 and 100 s) followed by application of vacuum for 5 min. Bars represent the means and standard error of at least 3 independent experiments with 20–40 plants each. Statistical significance is marked by * (P < 0.1). B and C Photographs of 5-week-old plants without sonication treatment (B) and submitted to 100 s sonication at the age of 3 days old(C). D to G Scanning electron micrographs of a 3-day-old cotyledons without sonication (D) and cotyledons after 10 s (E), 50 s (F) and 100 s (G) sonication. Arrows point to damage on cotyledon surfaces caused by sonication. Bars correspond to 125 µm