不同种植方式对玉米冠层调控及产量的影响

Effects of Different Planting Patterns on Canopy Regulation and Yield in Maize

以优良玉米杂交种‘良玉99’为试验材料,设置等行距种植(CK)和二比空、大垄双行、偏垄宽窄行3种不均匀种植方式,研究不均匀种植方式对玉米冠层结构特征、光合特性、田间小气候及产量的影响。两年研究结果表明:与常规种植相比,二比空、大垄双行和偏垄宽窄行增加生育后期叶面积指数,降低叶片衰老速率;显著增加穗位中下层茎叶夹角,穗位层叶片垂直占有率增加4.44%~7.15%。改变种植方式显著增加穗位中下层风速和田间温度,降低各冠层层次相对湿度,显著增加穗下层二氧化碳浓度。3种不均匀种植方式显著改善各冠层层次光合特性,透光率增加7.91%~52.58%,净光合速率、蒸腾速率、气孔导度分别增加1.39%~36.55%、2.78%~18.98%、5.88%~45.75%。光能利用率方面,2018年大垄双行和二比空籽粒产量光能利用率显著高于常规种植,增加25.93%和29.63%,2019年大垄双行生物产量和籽粒产量光能利用率分别增加6.62%和7.46%。3种不均匀种植方式产量提高14.16%~30.34%和4.19%~9.28%,两年均以大垄双行产量最高,达6264.68 kg·hm^(-2)(2018)和12449.40 kg·hm^(-2)(2019)。综合各项指标来看,大垄双行为最优的玉米种植方式在相应区域大面积推广应用。

In this study,the excellent maize hybrid‘Liangyu 99’was used as the material,the different planting patterns such as equidistant row spacing(CK),two-row with big ridge,partial ridge-narrow/wide row and 2-0 culture were designed to study the influence of non-uniform planting patterns on canopy structure characteristics,photosynthetic characteristics,field microclimate and yield in maize.Two years of results indicated that compared with the conventional planting,the 2-0 culture,two-row with big ridge and partial ridge-narrow/wide row could increase the leaf area index at late stage of development,and decrease the leaf senescence rate;the angle between the stems and leaves of the middle and lower layers of the panicle significantly increased;the vertical leaf occupancy rate in the ear position layer increased by 4.44%-7.15%.The change of the planting patterns significantly could increase the wind speed and temperature in the middle and lower ear positions,lower the relative humidity of every canopy layer,and significantly increase the carbon dioxide concentration in the lower ear.The three non-uniform planting patterns significantly improved photosynthetic characteristics of canopy layers,the light transmittance increased by 7.91%-52.58%,the population net photosynthetic rate,transpiration rate,and stomatal conductance increased by 1.39%-36.55%,2.78%-18.98%,5.88%-45.75%,respectively.In terms of light energy utilization rate,the grain yield light energy utilization efficiency of two-row with big ridge and 2-0 culture were significantly higher than that of conventional planting patterns in 2018,which increased by 25.93%and 29.63%,the biomass light energy utilization rate and grain yield light energy utilization rate of two-row with big ridge increased by 6.62%and 7.46%in 2019,respectively.The yield of the three non-uniform planting patterns increased by 14.16%-30.34%and 4.19%-9.28%,respectively;the two-row with big ridge had the highest grain yield in two years,reaching 6264.68 kg·hm^(-2)(2018)and 12449.40 kg·hm^(-2)(2019).In terms of comprehensive indicators,the maize planting pattern of two-row with big ridge is the optimal maize planting pattern to be popularized and applied on a large scale in the corresponding area.