氮素供应对春玉米产量及冠层部分指标的影响与相关分析

采用辽宁地区5个地方品种进行低、中、高3个氮素水平的比较试验(N0:不施氮、N1:112 kg/hm~2、N2:225 kg/hm~2),探究氮素对玉米冠层指标的影响及与产量因素的相关性。相关、逐步回归分析表明,随着施氮量升高,品种产量和穗粒数显著提高。不同氮素水平下,冠层指标与产量因素相关性有差异。穗粒数在N0处理下,与吐丝期叶氮比(SLN)和叶片氮浓度呈负相关,相关强度排序为吐丝期SLN吐丝期叶片氮浓度;N1处理下,与乳熟期LAI呈正相关,与吐丝期叶片氮浓度和吐丝期绿叶数呈负相关,相关强度排序为吐丝期叶片氮浓度乳熟期LAI吐丝期绿叶数;N2处理下,穗粒数与冠层指标相关性不显著。百粒重在N0处理下,与吐丝期穗位叶SPAD值呈正相关,与吐丝期LAI和乳熟期穗位叶SPAD值呈负相关,相关强度排序为吐丝期LAI吐丝期SPAD乳熟期SPAD;N1处理下,与乳熟期穗位叶SPAD值呈正相关,与乳熟期LAI呈负相关,相关强度排序为乳熟期LAI乳熟期SPAD值;在N2处理下,与吐丝期比叶面积(SLA)、SLN、乳熟期绿叶数呈负相关,相关强度排序为吐丝期SLN、SLA乳熟期绿叶数。

Effects and Correlative Analysis of Nitrogen Supply on Yield and Partial Canopy Characters of Spring Maize

In order to research the effects of partial canopy characters at different nitrogen levels and correlation between yield facts and canopy characters, this experiment were conducted under three nitrogen levels(low, middle, high) by using five local cultivars in Liaoning province, no nitrogen N0; N1 112 kg/ha; N2:225 kg/ha. The results of correlation and stepwise regression showed that, the yield and the number of grains per spike were significantly increased with increasing nitrogen level, the SPAD value of ear leaf, leaf nitrogen concentration, leaf nitrogen ratio, leaf area index of each cultivar showed an increasing trend. The correlation between canopy characters and yield factors is significantly under different nitrogen levels. Under N0, Kernels number per spike was negatively correlated with canopy traits, the order was leaf nitrogen ratio > the nitrogen concentration in the silking stage; Under N1, the correlation showed positive correlated with LAI at silking, but negatively correlations with other traits, the order was leaf nitrogen concentration at silking stage > LAI at silking stage > green leaf number at milky stage. Under N2, the intensity of correlation was not exactly, there was no exact advantage trait. Under N0, the correlation between 100-kernel weight and SPAD of ear leaf at silking was positive, negatively to other traits,the order was:LAI at silking > SPAD at silking > SPAD at milky; Under N1, it was positive correlated with SLN at milking, and negatively with LAI at silking, the order was LAI at silking > SLN at silking; Under N2, the correlation with main traits were negatively, the order was SLN, SLA of silking > green leaf No. at milky stage.