高油玉米籽粒灌浆期间氮素的吸收与分配

 大田生长条件下，以普通玉米为对照比较研究了高油玉米授粉后氮的吸收与分配规律。结果表明，与普通玉米相比，高油玉米籽粒灌浆期间籽粒氮的百分含量较高，而叶片和茎秆中氮的百分含量低于普通玉米，成熟期植株中的氮在籽粒中的分配比例较普通玉米高，平均高6.9%；形成100 kg籽粒所需氮量高于普通玉米，平均高0.13 kg，但品种间存在较大差异；营养体中氮的输出率比普通玉米低，籽粒中氮的来源主要依赖于籽粒灌浆期间直接从土壤中的吸收，占籽粒氮的70.05%（普通玉米为40.65%）。说明高油玉米的需氮量大且籽粒灌浆期间吸收的比例相对较高。

Uptake and Partitioning of Nitrogen in High Oil Corn During Grain Filling Period

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.