Figure 2. Effects of different concentrations of ethephon on adventitious root development.

The primary root system was removed from hypocotyls of 7-day-old germinated cucumber. Explants were incubated with distilled water or different concentrations of ethephon and indicated for 7 days. The number (A) of adventitious roots per explant were expressed as mean ±  SE (n = 20 explants from each of four independent experiments). Bars with different lowercase letters were significantly different (Duncan’s multiple range test, P < 0.05. Photographs (B–G) show hypocotyl explants after 7 days of the treatments indicated.