氮高效玉米杂交种穗三叶氮积累及生理特性对氮效率的贡献

试验选择不同氮效率的超高产玉米杂交种为材料,应用裂区设计,通过逐步回归和相关分析,研究氮高效杂交种穗三叶生理特性及穗三叶氮积累特点,明确穗三叶氮积累量及生理特性对氮效率的贡献。结果表明,不论是否施用氮肥,吸收效率对氮效率的贡献均高于利用效率,是氮效率差异的主要来源,且高效型杂交种吐丝期穗三叶含氮量及转移量均高于低效型。低氮下,穗三叶吐丝期含氮量、光合速率、胞间CO2浓度、穗三叶硝酸还原酶含量对氮效率的贡献较大,是低氮高效品种筛选的重要指标;高氮下,穗三叶吐丝期含氮量、光合速率、穗三叶硝酸还原酶含量对氮效率贡献较大,是高氮高效品种筛选的重要指标。

Contribution of Nitrogen Efficient Maize Hybrid Spike 3 Leaf Nitrogen Accumulation and Physiological Characteristics to the Nitrogen Efficiency

In order to clarify the contribution of spike three nitrogen accumulation and physiological characteristics to nitrogen efficiency, the different nitrogen efficient super-high-yield maize hybrids were selected as material, using split plot design, through stepwise regression and correlation analysis, to study the physiological characteristics and nitrogen accumulation characteristics of nitrogen efficient maize hybrid spike three leaves. The results showed that, regardless of whether the application of nitrogen fertilizer, the contribution of the absorption efficiency of nitrogen utilization efficiency is higher than the efficiency of nitrogen use efficiency. It is the main source of the differences, nitrogen content and transfer of efficient spike three were higher than inefficient. Under low nitrogen, the nitrogen content of spike three in silking, photosynthetic rate, CO₂ concentration in the intercellular, and NAR, are larger contribution to the nitrogen efficiency, they are an important index of low nitrogen efficient varieties screening. Under high nitrogen, the nitrogen content of spike three in silking and NAR are larger contribution to the nitrogen efficiency, they are an important index of high nitrogen efficient varieties screening.