Facilitation of wheat to phosphorus uptake by soybean in the wheat soybean intercropping

A pot experiment was conducted to investigate the interspecific facilitation of wheat to the phosphorus uptake by soybean in the spring wheat soybean intercropping.The pots were separated into two compartments by either plastic sheet to eliminate root contact and any solute movement between two crop root systems or by nylon net (30μm) to prevent root contact between two crops while permitting solute exchange between them.In addition, a control treatment was used where no separation was made to the pot.Wheat plants were grown in one compartment and soybean in the other.The obvious facilitation of wheat to phosphorus uptake by soybean was observed in pot with net separation,where competition of wheat to phosphorus was eliminated.The biomass,root activity and phosphorus uptake of soybean for nylon net separation treatment were 150%,45.2% and 134% higher than those for plastic sheet separation treatment,respectively.In pots with nylon net separation,more roots of soybean were distributed near the nylon net on which wheat formed a dense root mat in the other side.In contrast,soybean roots distributed more or less evenly in the whole compartment for treatment of plastic sheet.It was supposed that the beneficial effect of soybean was resulted from the rhizosphere effect of wheat.