A recombinant inbred lines population(RILs)of 163 lines derived form a cross of Dasanbyeo(indiaca)/TR22183(japonica)was evaluated for analyzing inheritance of traits: nitrogen-absorbing ability and nitrogen-utilizing efficiency of rice at the maturity stage by the major genes plus polygenes mixed inheritance model of quantitative traits in plant.

A research was conducted to determine the effects of nitrogen application rate on soil in organic nitrogen distribution,microbial biomass nitrogen content,nitrogen uptake and utilization in wheat.

The difference of yield and its components, dry matter production, sink-source relationship, nitrogen uptake and utilization, root morphometrics traits and activity .

A root barrier pot experiment was employed to investigate the nitrogen uptake and utilization and interspecies reciprocity of "wheat/maize/soybean" and "wheat/maize/sweet potato".

Effects of different nitrogen applying amount (50, 100, 150, 200kg/hm~2) and assigning proportion of nitrogen fertilizer(applying basic N and tillering N as 2:0andll:l)on plant height, leaf number, the dry weight of plant, N uptake and utilization, yield and quality of Alism a plantago-aquatica Linn were studied, by taking the treatment without applying nitrogen as CK.

Correlation analysis indicated that there existed significant or highly significant positive correlations between yield and indices of N uptake and utilization,which also illustrated that the higher yield of Indica rice was from the intensive N absorption of its plant.