Two different types of cones were used for this experiment: super high yielding corns and common yield corns. Through determining the main enzyme activity and physiological indexes in growth stage, compared the difference in resist senescence between high yielding corns and common corns, the characteristic of physiology and biochemistry were explored in order to know the mechanism of high yield. And the theory of super-high-yield breeding and planting. High yield types of corns: Xianyu335, Zhengdan958; comm...