Interspecific competition and facilitation for nutrient in wheat and legumes intercrops

The interspecific nutrient competition and facilitation between wheat intercropped with faba bean and wheat intercropped with soybean are studied using the root partition technique．The results show that not only the wheat shoot biomass but also its nutrient acquisition are higher in roots mixed treatment than those of either solid barrier or 30um nylon mesh barrier．In wheat-soybean system，both the shoot biomass and nutrient acquisition of soybean decrease without barrier due to the root interaction between wheat and soybeans．However，in wheat-faba bean system，both the shoot biomass and nutrient acquisition of faba bean are not reduced significantly without barrier in spite of root interaction between wheat and faba bean．Therefore，the competition of wheat is stronger both in wheat-soybean and wheat-faba bean systems than those of faba bean and soybean．The interspecific competition exists in wheat-soybean and the interspecific facilitation exists in wheat-faba bean system．