"Low-tu" has long been recognized as a main soil type in China.This soil is oecurring on the loessial plateau of Shaanxi and Shanxi provinces of northwestern China and developed on drab soil after a long history of cultivation and manuring. Continuous deposition of loessial materials results the soil slightly ealcareous,with a thick and loose surface soil of silty loam texture,characterizing as the "Low-tu" horizon.This old cultivated horizon usually has a depth up to one meter,under which is a clay accumulated layer,subsequently a lime accumulated layer,and then the parent material of original drab soil.Pot culture experiments with corn plant were made separately for the soil samples of these four horizons.The soil and Plants were analysed and interaetions of P-Zn were explained.