Physiological Responses of Sweet Potato Callus to Drought Stress

Callus of sweet potato Lu-xuan 1 were cultured under drought stress,then the effects on water potential,contents of soluble protein,soluble sugar,proline,and activities of SOD,POD and CAT were studied in order to understand the physiological mechanism of sweet potato callus resistance to drought stress at cell level.The results showed as follows: the permeability of cytoplasm membrane of sweet potato callus increased prominently and the water potential of them decreased under drought stress;soluble protein contents decreased under slight drought stress but increased under severe stress;SOD activities increased under moderate and severe stress;POD activities decreased under different degrees of drought stresses;CAT activities increased under moderate and severe stress;contents of proline and soluble sugar increased under different degrees of drought stresses.