Scientia Agricultura Sinica ›› 2020, Vol. 53 ›› Issue (10): 1959-1970.doi: 10.3864/j.issn.0578-1752.2020.10.004

• TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY • Previous Articles     Next Articles

Effects of Tillage, Nitrogen Application, Planting Density and Their Interaction on Soil Moisture and Yield Formation of Spring Maize in Dryland

LI Ao,ZHANG YuanHong,WEN PengFei,WANG Rui,DONG ZhaoYang,NING Fang,LI Jun()   

  1. College of Agronomy, Northwest A&F University, Yangling 712100, Shaanxi
  • Received:2019-09-16 Accepted:2019-12-13 Online:2020-05-16 Published:2020-05-22
  • Contact: Jun LI E-mail:junli@nwsuaf.edu.cn

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Abstract:

【Objective】The semi-humid and arid areas on the Loess Plateau belong to rain-fed agricultural areas, in which water deficit is the main limiting factor for agricultural production. Therefore, a comprehensive cultivation mode of spring maize suitable for semi-humid and drought-prone areas on the Loess Plateau was screened to improve maize water use efficiency and yield. 【Method】During the 2017 and 2018 maize growing season, the effects of different tillage methods (conventional tillage, no-tillage, and subsoil tillage), nitrogen application (0, 150, and 225 kg·hm-2) and planting density (52 500 and 67 500 plants/hm2) on soil water dynamics, water use efficiency, crop growth, yield and its components in spring maize field were analyzed to improve the comprehensive utilization of maize. 【Result】 (1)The soil water storage (0-200 cm) of spring maize before sowing in 2017and 2018 showed the trend of NT>ST>CT, which under NT and ST increased by 6.1% and 4.1% than that under CT, respectively. In addition, water use efficiency was the highest under STH2 treatment during two consecutive years. (2) Compared with conventional tillage treatment, subsoiling and no-tillage treatment significantly increased leaf area index (LAI) and dry matter accumulation. LAI and dry matter accumulation of spring maize increased with the increase of density and nitrogen rates. The tillage×density interaction had significant effect on LAI at jointing and tasseling stages, and the effect of density×fertilization interaction had significant effect on LAI at filling stage. Compared with other treatments, the dry matter accumulation of STH2 treatment in maturity stage increased significantly by 3.3% -32.9%. (3)There was a significant positive correlation between nitrogen application and the number of grains per ear and 100-grain weight; the maize yield under subsoiling and no-tillage treatment was significantly higher than that under conventional tillage, among which the yield under STH2 treatment was the highest, and compared with other treatments, the maize yield under STH2 treatment increased by 1.4%-63.3% in 2017 and 2.9%-39.6% in 2018. 【Conclusion】Under the condition of subsoiling tillage, applying 150-225 kg·hm-2 nitrogen and 67 500 plants/hm2 planting density could not only improve water use efficiency of spring maize, but also obtain higher yield benefit, no-tillage, applying 225 kg·hm-2nitrogen and 67 500 plants/hm2 planting density could get the high economic benefit.

Key words: spring maize in dryland, tillage, nitrogen application, density, water use efficiency, yield

Table 1

Tillage, nitrogen application and density practices of different treatments"

耕作Tillage 施肥Fertilization 密度Density 处理Treatments
CT Z D1 CTZ1
L CTL1
H CTH1
NT Z NTZ1
L NTL1
H NTH1
ST Z STZ1
L STL1
H STH1
CT Z D2 CTZ2
L CTL2
H CTH2
NT Z NTZ2
L NTL2
H NTH2
ST Z STZ2
L STL2
H STH2

Table 2

Analysis of variance of soil moisture dynamics, WUE, LAI, dry matter accumulation and yield components in spring maize field under tillage, density, and nitrogen application"

指标
Indicator		 耕作
Tillage (T)		 密度
Density (D)		 施氮
Fertilization (F)		 耕作×密度
T×D		 耕作×施氮
T×F		 密度×施氮
D×F		 耕作×密度×施氮
T×D×F
土壤蓄水量及水分利用效率
Soil water content and WUE		 播种期蓄水量
Soil water storage at sowing		 <0.001 0.870 0.913 0.010 0.170 0.148 0.006
成熟期蓄水量
Soil water storage at maturity		 0.714 <0.001 <0.001 <0.001 <0.001 0.005 <0.001
水分利用效率
Water use efficiency		 <0.001 <0.001 <0.001 0.012 0.014 <0.001 0.005
叶面积指数
Leaf area index		 拔节期叶面积指数
LAI at jointing stage		 0.002 0.001 0.005 0.007 0.007 0.048 0.294
抽雄期叶面积指数
LAI at tasseling stage		 0.045 <0.001 <0.001 0.010 0.748 0.380 0.660
灌浆中期叶面积指数
LAI at mid-filling stage		 0.612 0.005 0.003 0.317 0.838 0.003 0.996
干物质积累
Dry matter accumulation		 抽雄期干物质积累
Biomass at tasseling stage		 0.012 <0.001 <0.001 0.152 0.020 <0.001 0.287
成熟期干物质积累
Total biomass at maturity stage		 <0.001 <0.001 <0.001 0.002 <0.001 0.060 0.007
产量及构成因素
Yield and components		 穗数Ear number <0.001 <0.001 <0.001 0.034 0.704 0.002 0.015
穗粒数Grains per ear <0.001 <0.001 <0.001 0.034 0.002 0.704 0.415
百粒重100-kernel weight 0.16 0.001 <0.001 0.512 0.017 0.764 0.028
产量Yield 0.001 <0.001 <0.001 0.016 0.011 0.018 0.028
收获指数HI <0.001 <0.001 <0.001 0.034 0.002 0.704 0.415

Fig. 1

Dynamic changes of soil water content of spring maize under different treatments in 2017-2018 (0 - 200 cm)"

Fig. 2

Water use efficiency of spring maize under different treatments from 2017 to 2018 Different lowercase letters represent significant differences at 5% level between different nitrogen application and density under the same tillage treatments"

Fig. 3

Effect of different treatments on the leaf area index of spring maize under different periods in 2017-2018"

Fig. 4

Effect of different treatments on the dry matter accumulation of spring maize in 2017-2018 PB stands for biomass at tasseling stage, and TB stands for total biomass. Different uppercase letters represent significant differences at 5% level between tillage treatments; Different lowercase letters represent significant differences at 5% level between fertilization treatments; * represent statistically significant differences at 5% level at different densities; NS stands for no significance"

Fig. 5

Path analysis of yield and its constituent factors under different treatments"

Fig. 6

Changes in yield of spring maize under different treatments"

Table 3

Cost and return of maize production under different treatments in 2017-2018 (yuan/hm2)"

处理
Treatment		 总投入
Total cost		 产量收入Yield income 纯收益Return
2017 2018 2017 2018
CTZ1 9355 2469 11242 -6886c 1887c
CTZ2 9455 3613 12150 -5842ab 2695b
CTL1 9845 3674 12619 -6171b 2774b
CTL2 9945 4755 13334 -5190a 3389ab
CTH1 10135 3162 14472 -6973c 4337a
CTH2 10235 5318 14813 -4917a 4603a
NTZ1 8680 2814 10710 -5866c 2030d
NTZ2 8780 3944 13773 -4836b 4993c
NTL1 9170 4285 14578 -4885b 5408b
NTL2 9270 5779 15181 -3491a 5911b
NTH1 9460 4069 15301 -5391c 5841b
NTH2 9560 6298 17218 -3262a 7658a
STZ1 9430 3450 11376 -5980c 1946c
STZ2 9530 4589 13576 -4941b 4046b
STL1 9920 5008 14469 -4912 4549b
STL2 10020 6683 16232 -3337a 6212ab
STH1 10210 5699 14813 -4511b 4603b
STH2 10310 6733 17723 -3577a 7413a
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