Effect of Potassium on Soybean Leaf Protective Enzymes and Yield under Drought Stress

In order to elucidate the alleviate effect of potassium on drought stress of soybean,pot experiment simulated drought environment were set and the activities of superoxide dismutase(SOD),catalase(CAT) and peroxidase(POD) in different potassium treatments on soybean cultivar Heinong 44 were determined.The results showed that potassium enhanced the activities of the enzymes and 0.42 g K2O· kg-1soil treatment was the best one.The response of SOD and CAT were important under slight stress and POD was more significant under severe stress.The yield increased by 3.8 to 18.6 percent with the increase of potassium under slight and moderate drought stress,while had no yield increasing effect under severe drought stress.