The content of mineralizable nitrogen (MAN), total nitrogen (TN) and organic matter (OM) at different depth of soils were analysed to study the relationships between these three indices and crop uptake of nitrogen (CUN).

The relationship between mineralizable soil N and crop N uptake was studied under the condition of pot and field experoments respectively.

Shoot/root Biomass and Crops N-content Analysis of Maize/faba Bean,Wheat/faba Bean and Barley/faba Bean Intercropping Systems;

Effect of Controlled-release Urea Application on N Uptake and Rice Yield;

The effects on maize N uptake by arbuscular mycorrhizal fungi screened from South China, Center China and North China in cinnamon soil, brown soil and red soil collected in above three regions were investigated using three-compartment-glass-bead culture system.

In the fababean/maize intercropping system,shoot N content of fababean or maize and total N,NO3——N,NH4+-N content of 0-20 cm soil were not markedly increased by rhizobium inoculation compared with the check regardless of whether receiving nil or 225 kg/ha N,but the total shoot N uptake in the intercropping system was significantly improved by rhizobium inoculation.