Effect of power ultrasound on induction of Stachys sieboldii leaf callus and growth of axillary bud

Using the power ultrasound 27 KHz and 40 KHz respectively to treat with Stachys sieboldii in different treatment time then the treated materials were sub cultured. We observed that the leaves callus formation time of ultrasound treatment groups was shortened comparing with the control ones. However, there was no apparent difference during the later growing period. The axillary buds of ultrasound treatment groups grow better than the control ones, such as increased height and thickened stem. It shows that power ultrasound, to some degree, could stimulate the growth of plant.