控释肥用量对旱作夏玉米叶片含氮量时空分布的影响

Effects of Controlled-release Fertilizer Application Rates on the Temporal and Spatial Distribution of Leaf Nitrogen Content of Dry Land Summer Maize

为了明确控释肥用量对夏玉米氮素营养的影响,以‘郑单958’为试验材料,设0、682、1023、1364 kg/hm2共4种施肥量,研究了叶片含氮量的时空分布。结果表明,施肥量、叶位和取样时期的主效显著,施肥量×叶位互作不显著,而施肥量×取样时期互作显著。出苗后,玉米叶片含氮量大喇叭口期达到最大值,成熟期降到最低;玉米叶片含氮量均表现为中位叶的值最大,而上位叶和下位叶的相对大小出现波动。各部位叶片氮素含量随施肥量发生变化,但时空分布模式并未发生改变。玉米中位叶叶片含氮量和产量呈显著正相关,在施肥量为1023 kg/hm2时均达到最大值。玉米中位叶可以作为监测玉米氮素营养状况的指示性叶位。

The objective of experiment was to quantify effects of controlled-release fertilizer application rates on summer maize nitrogen nutrition,the temporal and spatial distribution of leaf nitrogen content of summer maize,cultivar‘Zhengdan958＇,was examined. Four application levels of controlled release fertilizer were designed as 0,682,1023,1364 kg/hm2respectively. The results showed that：all three main effects on leaf nitrogen content of application rates,leaf-position and sampling period was significant,the same was the interaction between application and sampling period,but the interaction between application rates and leaf-position was not. After emergence,maize leaf nitrogen content was the highest at big trump stage,and the least at maturity stage. Leaf nitrogen contents of middle layer leaves were the largest,compared to the upper and lower layer leaves,of which leaf nitrogen contents appeared to be of fluctuation. Thought leaf nitrogen contents of different layer leaves changed due to fertilizer application rates,the temporal and spatial distribution pattern didn＇t changed. There was significant positive correlation between middle layer leaf nitrogen content and crop yield,which reached the maximum value when fertilizer application rate was1023 kg/hm2. The middle layer leaf could be used as the indicative leaf position of monitoring maize＇s nitrogen nutritional status.