华北区部分主栽玉米杂交种的氮效率分析

Nitrogen Use Efficiency in Some of Main Maize Hybrids Grown in North China

玉米生产中氮肥的过量施用,不但导致氮肥利用率下降,生产成本提高,而且还会造成地下水污染,因而越来越受到人们的重视。选用氮高效作物品种是解决这些问题的重要途径。本试验利用华北地区主栽的8个杂交种在高、低氮条件下研究了产量、吸氮量、氮效率及其生理基础。两年结果表明,不同玉米杂交种的产量、氮效率和不同生育期吸氮量都存在显著的基因型差异。农大108高、低氮条件下都有较高产量,且吸氮量高,成熟期茎秆氮残留多。中单2996在两个氮水平和两种土壤条件下,吸氮量相对较高,茎秆残留少,氮转移率较高。通径分析表明,吸收效率对氮效率的直接作用大于利用效率的直接作用,是氮效率的主要来源。

Overdose of nitrogen(N)fertilizers may cause lower N use efficiency,higher input,as well as nitrate pollution of groundwater.Nitrogen efficient maize hybrids can be an important way to solve such problems.In the present study,eight maize hybrids from North China were used to investigate their response to low and high N in yield,N uptake and N efficiency.Two year's results showed that significant genotypic difference existed in yield,N efficiency,N uptake in different development stage,Nongda108got highest yield under both high and low nitrogen level,with highest N uptake and N residual in stalks.Zhongdan2996had higher N uptake,lower N residual in stalks,hence higher N translocation efficiency.Path analysis indicated that N uptake efficiency had significant role in determining N efficiency under both N levels.