Impact of Phosphorus Deficiency Stress on Root Morphology, Nitrogen Concentration and Phosphorus Accumulation of Soybean(Glycine max L.)

A sand experiment was conducted to study the effects of phosphorus deficiency stress on root morphology, total nitrogen concentration and phosphorus accumulation in soybean (Glycine max L.) at glassroom condition. The results showed that phosphorus deficiency stress improved root growth which embody in root length, root surfacearea and root volume all increased compared with normal phosphorus supplying so that the uptake of soybean roots for phosphorus was increased. The total nitrogen concentration in soybean plant increased with the concentration of P in supplying nutrient solution. While phosphorus deficiency restrained the absorption of soybean for N and P, N and P content in grain was the highest than that in other organs of soybean, and N concentration in nodule was higher than that in shoot and root, suggested that nodule was a main site for nitrogen reserving. There was significant difference between no P and high P treatment, and low P and high P treatment (P5%). Phosphorus deficiency enhanced the efficiency of P absorption while made the efficiency of P utilization dropped compared with normal P supplying, this is an adaptation mechanism of soybean to phosphorus deficiency.