Physiological responses of exotic weeds Gaura parviflora to drought stress.

Gaura parviflora was treated with drought stress,the content of free proline,malon-dialdehyde(MDA),chlorophyll and the activity of superoxide dismutase(SOD) were investigated.The results showed that Gaura parviflora could maintain high SOD activity,large proline gain,low rate of MDA accumulation,chlorophyll content increased slightly,the ratio of chlorophyll a and b was raised at the beginning and then decreased.It could be confirmed that its cell membrane system was harmed lightly.In addition,the recovery speed of physiological function was fast after rewater treatments,which indicated that Gaura parviflora had stronger drought resistance and recovery than field crops.