Effect of Soybean and Wheat on the Mobilization of Mineral Potassium

Mobilization of mineral potassium by plants was investigated.The amount of mineral potassium releasing from muscovite and feldspar ranged from 19.53mg kg~(-1) to 45.46mg kg~(-1).we fould that spring wheat and soybean roots could excrete more oxalic acid,tartaric acid and citric acid than the other organic acids.Oxalic acid had highest mobilization effect than the other organic acid and inorganic acid solution utilized.Low-molecular-weigh organic acids could have destructive effect on the k-bearing minerals,but their mobilization effect on K release was not significant.In conclusion,oxalic acid,tartaric acid and citric acid are the dominative organic acids in spring wheat and soybean root exudation which determines mineral potassium releasing.