为明确不同氮肥运筹对玉米根冠协调发育的影响,基于长期定位氮肥试验平台,设置4个氮素处理(N3:300 kg N/hm^(2);N2:225 kg N/hm^(2);N1:150 kg N/hm^(2);N0:0 kg N/hm^(2)),2023-2024年以郑单958和先玉3352个玉米品种为试验材料,分析玉...为明确不同氮肥运筹对玉米根冠协调发育的影响,基于长期定位氮肥试验平台,设置4个氮素处理(N3:300 kg N/hm^(2);N2:225 kg N/hm^(2);N1:150 kg N/hm^(2);N0:0 kg N/hm^(2)),2023-2024年以郑单958和先玉3352个玉米品种为试验材料,分析玉米关键生育期根冠特征。结果表明,增施氮肥显著提高玉米产量及地上部和地下部的生物量,但N2与N3处理间产量差异不显著,N3、N2、N1处理成熟期干物质积累量较N0分别增加了106.5%~164.3%、87.4%~125.7%、71.8%~87.4%;根系干重峰值出现在吐丝后15 d左右,N3、N2、N1处理较N0处理分别增加了33.67%~49.67%、17.87%~21.89%、9.69%~18.38%。根冠比动态呈单峰曲线,峰值出现在出苗后45 d左右,随施氮量增加而降低,N2处理较N1、N0处理分别降低11.1%和25.7%,较N3处理增加4.1%。研究结果表明,氮肥投入影响玉米产量的增加,当施氮量超过225 kg N/hm^(2)时,增产效应趋于饱和。合理的氮肥运筹(中氮,N2)通过优化物质分配比例,协调根冠生长,在保障产量提升的同时提高了肥料利用效益,为玉米氮肥精准调控及可持续生产提供了依据。展开更多
The rate of corn kernel breakage in the grain combine harvesters is a crucial factor affecting the quality of the grain shelled in the field. The objective of the present study was to determine the susceptibility of c...The rate of corn kernel breakage in the grain combine harvesters is a crucial factor affecting the quality of the grain shelled in the field. The objective of the present study was to determine the susceptibility of corn kernels to breakage based on the kernel moisture content in order to determine the moisture content that corresponds to the lowest rate of breakage.In addition, we evaluated the resistance to breakage of various corn cultivars. A total of 17 different corn cultivars were planted at two different sowing dates at the Beibuchang Experiment Station, Beijing and the Xinxiang Experiment Station(Henan Province) of the Chinese Academy of Agricultural Sciences. The corn kernel moisture content was systematically monitored and recorded over time, and the breakage rate was measured by using the grinding method. The results for all grain samples from the two experimental stations revealed that the breakage rate y is quadratic in moisture content x,y=0.0796 x^(2)-3.3929 x+78.779;R^(2)0=0.2646, n=512. By fitting to the regression equation, a minimum corn kernel breakage rate of 42.62% was obtained, corresponding to a corn kernel moisture content of 21.31%. Furthermore, in the 90% confidence interval, the corn kernel moisture ranging from 19.7 to 22.3% led to the lowest kernel breakage rate, which was consistent with the corn kernel moisture content allowing the lowest breakage rate of corn kernels shelled in the field with combine grain harvesters. Using the lowest breakage rate as the critical point, the correlation between breakage rate and moisture content was significantly negative for low moisture content but positive for high moisture content. The slope and correlation coefficient of the linear regression equation indicated that high moisture content led to greater sensitivity and correlation between grain breakage and moisture content. At the Beibuchang Experiment Station, the corn cultivars resistant to breakage were Zhengdan 958(ZD958) and Fengken 139(FK139), and the corn cultivars non-resistant to breakage were Lianchuang 825(LC825), Jidan 66(JD66), Lidan 295(LD295), and Jingnongke 728(JNK728). At the Xinxiang Experiment Station, the corn cultivars resistant to breakage were HT1, ZD958 and FK139, and the corn cultivars non-resistant to breakage were ZY8911, DK653 and JNK728. Thus, the breakage classifications of the six corn cultivars were consistent between the two experimental stations. In conclusion, the results suggested that the high stability of the grinding method allowed it to be used to determine the corn kernel breakage rates of different corn cultivars as a function of moisture content, thus facilitating the breeding and screening of breakage-resistant corn.展开更多
文摘为明确不同氮肥运筹对玉米根冠协调发育的影响,基于长期定位氮肥试验平台,设置4个氮素处理(N3:300 kg N/hm^(2);N2:225 kg N/hm^(2);N1:150 kg N/hm^(2);N0:0 kg N/hm^(2)),2023-2024年以郑单958和先玉3352个玉米品种为试验材料,分析玉米关键生育期根冠特征。结果表明,增施氮肥显著提高玉米产量及地上部和地下部的生物量,但N2与N3处理间产量差异不显著,N3、N2、N1处理成熟期干物质积累量较N0分别增加了106.5%~164.3%、87.4%~125.7%、71.8%~87.4%;根系干重峰值出现在吐丝后15 d左右,N3、N2、N1处理较N0处理分别增加了33.67%~49.67%、17.87%~21.89%、9.69%~18.38%。根冠比动态呈单峰曲线,峰值出现在出苗后45 d左右,随施氮量增加而降低,N2处理较N1、N0处理分别降低11.1%和25.7%,较N3处理增加4.1%。研究结果表明,氮肥投入影响玉米产量的增加,当施氮量超过225 kg N/hm^(2)时,增产效应趋于饱和。合理的氮肥运筹(中氮,N2)通过优化物质分配比例,协调根冠生长,在保障产量提升的同时提高了肥料利用效益,为玉米氮肥精准调控及可持续生产提供了依据。
基金financially supported by the National Key Research and Development Program of China(2016YFD0300110,2016YFD0300101)the National Natural Science Foundation of China(31371575)+1 种基金the China Agriculture Research System of MOF and MARA(CARS-0225)the Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Science。
文摘The rate of corn kernel breakage in the grain combine harvesters is a crucial factor affecting the quality of the grain shelled in the field. The objective of the present study was to determine the susceptibility of corn kernels to breakage based on the kernel moisture content in order to determine the moisture content that corresponds to the lowest rate of breakage.In addition, we evaluated the resistance to breakage of various corn cultivars. A total of 17 different corn cultivars were planted at two different sowing dates at the Beibuchang Experiment Station, Beijing and the Xinxiang Experiment Station(Henan Province) of the Chinese Academy of Agricultural Sciences. The corn kernel moisture content was systematically monitored and recorded over time, and the breakage rate was measured by using the grinding method. The results for all grain samples from the two experimental stations revealed that the breakage rate y is quadratic in moisture content x,y=0.0796 x^(2)-3.3929 x+78.779;R^(2)0=0.2646, n=512. By fitting to the regression equation, a minimum corn kernel breakage rate of 42.62% was obtained, corresponding to a corn kernel moisture content of 21.31%. Furthermore, in the 90% confidence interval, the corn kernel moisture ranging from 19.7 to 22.3% led to the lowest kernel breakage rate, which was consistent with the corn kernel moisture content allowing the lowest breakage rate of corn kernels shelled in the field with combine grain harvesters. Using the lowest breakage rate as the critical point, the correlation between breakage rate and moisture content was significantly negative for low moisture content but positive for high moisture content. The slope and correlation coefficient of the linear regression equation indicated that high moisture content led to greater sensitivity and correlation between grain breakage and moisture content. At the Beibuchang Experiment Station, the corn cultivars resistant to breakage were Zhengdan 958(ZD958) and Fengken 139(FK139), and the corn cultivars non-resistant to breakage were Lianchuang 825(LC825), Jidan 66(JD66), Lidan 295(LD295), and Jingnongke 728(JNK728). At the Xinxiang Experiment Station, the corn cultivars resistant to breakage were HT1, ZD958 and FK139, and the corn cultivars non-resistant to breakage were ZY8911, DK653 and JNK728. Thus, the breakage classifications of the six corn cultivars were consistent between the two experimental stations. In conclusion, the results suggested that the high stability of the grinding method allowed it to be used to determine the corn kernel breakage rates of different corn cultivars as a function of moisture content, thus facilitating the breeding and screening of breakage-resistant corn.
