不同栽培管理条件下夏玉米产量与肥料利用效率的差异解析

于2017—2018年在泰安、淄博和烟台,根据生产调研和各地夏玉米高产经验,在同一地块综合设置了超高产栽培、高产高效栽培和农户栽培3种栽培模式,分别模拟超高产生产水平(SH)、高产高效生产水平(HH)和农户生产水平(FP) 3个层次。并分别设置不施氮(SHN_0、HHN_0、FPN_0)、不施磷(SHP_0、HHP_0、FPP_0)和不施钾(SHK_0、HHK_0、FPK_0)的肥料空白处理。定量分析不同产量层次之间产量差及肥料利用效率差,探究产量差和效率差的影响因素及缩差增效途径。结果显示,当前山东省夏玉米SH、HH和FP的籽粒产量分别实现了光温潜力产量的68.13%、63.71%、53.22%。随着产量差距的增大,肥料利用效率降低。FP的N、P、K肥料利用效率分别为4.23、5.83、4.94 kg kg~(–1), SH的分别为3.84、4.64、2.97 kg kg~(–1)。通过优化栽培措施后,高产高效管理模式能够较FP籽粒产量提升10.49%, N、P、K的肥料利用效率分别提高67.07%、101.35%、57.65%,是实现产量与肥料利用效率协同提升的有效技术途径。对各产量水平进行产量性能分析发现,随着产量水平的提高,平均叶面积指数和单位面积穗数明显提高,而穗粒数、平均净同化率和粒重则有所下降。随着产量水平的提高,吐丝后干物质和N、P、K元素积累比例有增加的趋势。因此,在保持现有功能性参数不降低情况下,优化结构性参数是当前产量与资源利用效率协同提升的有效措施,今后高产高效应更加注重生育后期群体结构性能的优化。

Analysis of differences in summer maize yield and fertilizer use efficiency under different cultivation managements

Our study was conducted in Tai’an, Zibo, and Yantai city from 2017 to 2018. According to the production research and experience of high-yield summer maize, three cultivation modes simulating super-high production level (SH), high production and high-efficiency production level (HH), and farmer production level (FP) were comprehensively set up in the same plot. The fertilizer blanks were applied with no nitrogen (SHN₀, HHN₀, FPN₀), no phosphorus (SHP₀, HHP₀, FPP₀), and no potassium (SHK₀, HHK₀, FPK₀). Quantitative analysis of the yield gap and fertilizer utilization efficiency gap under different yield levels was carried out to explore the factors affecting yield gap and efficiency gap, and the way to reduce the gap and improve the efficiency. The grain yields of SH, HH, and FP of summer maize in Shandong province were realized 68.13%, 63.71%, and 53.22% of the potential yield of light and temperature. The fertilizer utilization efficiency decreased with the enlarged yield gap. The agronomic utilization rates of N, P and K fertilizers in FP were 4.23, 5.83, and 4.94 kg kg ^-1, respectively. The N, P, and K fertilizer utilization efficiencies of FP were 4.23, 5.83, and 4.94 kg kg ^-1, and those of SH were 3.84, 4.64, and 2.97 kg kg ^-1, respectively. After optimizing the cultivation measures, the high-yield and high-efficiency management mode increased the fertilizer utilization efficiency of N, P, and K by 67.07%, 101.35%, and 57.65%, respectively, and the output by 10.49%, as compared with FP. It is an effective technical way to achieve the synergistic improvement of yield and fertilizer use efficiency. The yield performance analysis of summer maize yields showed that with the increase of yield level, the mean leaf area index and the number of panicles per unit area increased significantly, while the number of kernels per panicle, average net assimilation rate and grain weight decreased. At the same time, with the increase of yield level, the accumulation ratio of biomass and N, P, and K uptake decreased in pre-silking stage, and increased in post-silking stage. Therefore, under the condition of keeping functional parameters unchanged on the existing basis, optimizing structural parameters is an effective measure for current yield and efficiency increase, and with the increase of yield, more attention should be paid to structural optimization in post-silking stage.