Abstract: The nitrogen uptake and partitioning in high oil corn (HOC) was studied under the growing conditions in field, and compared with normal corn (NC). The nitrogen concentration in grain of HOC was higher than that of NC, but lower in leaves and stalks. At maturity, the distribution of total N to grain in HOC was 6.9% higher than that in NC. As to absorption of N in 100 kg grain yield, there was 0.13 kg in HOC more than that in NC, whereas the nitrogen export rate of vegetable organs was lower. The percentage of N uptake during grain filling period to grain N was 70.05%, that of NC was 40.65%. That to say, the grain nitrogen of HOC was more contributed to N uptake by plant shoots during grain filling period than N translocation from vegetable organs. In conclusion, both the demand and rate of N uptake during grain filling period of HOC are higher. So if HOC achieves the same grain yield as NC, abundant nitrogen fertilization during grain filling period will be very important.

Key words: High oil corn, Grain, Filling period, Nitrogen