Optimizing Grain Yield and Water Use Efficiency Based on the Relationship between Leaf Area Index and Evapotranspiration
Abstract
:1. Introduction
2. Materials and Methods
2.1. Experimental Region and Site
2.2. Experimental Design
2.3. Irrigation System and Agronomic Practices
2.4. Sampling and Measurements
2.5. Statistical Analysis
3. Results
3.1. Grain Yield, Kernel Number, Kernel Weight, ETa, and WUE
3.2. Relationship between Grain Yield and Plant Density
3.3. Relationships between LAI and Plant Density, and LAI and Irrigation Level
3.4. LAI, Grain Yield, and ETa
3.5. Theoretical Optimal Irrigation Level, LAI, and WUE
4. Discussion
4.1. The Balance between Agricultural Production and Its Environmental Impacts
4.2. Effects of Density and Irrigation on Grain Yield
4.3. Ways to Increase Grain Yield and Production Efficiency in the Future
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Month | Precipitation (mm) | Average Temperature (°C) | Sunshine Hours (h) | ||||||
---|---|---|---|---|---|---|---|---|---|
2016 | 2017 | 2008–2017 Average | 2016 | 2017 | 2008–2017 Average | 2016 | 2017 | 2008–2017 Average | |
April | 20.5 | 29.9 | 23.1 | 14.8 | 13.0 | 11.1 | 6.9 | 6.2 | 8.9 |
May | 31.7 | 42.7 | 24.8 | 15.0 | 16.9 | 17.1 | 7.9 | 9.2 | 9.9 |
June | 75.6 | 72.2 | 28.2 | 22.6 | 21.1 | 21.8 | 8.4 | 7.3 | 9.7 |
July | 42.1 | 0.9 | 25.8 | 23.3 | 24.1 | 23.5 | 7.8 | 9.8 | 9.7 |
August | 36.5 | 18.9 | 25.0 | 21.8 | 20.9 | 21.7 | 7.1 | 8.9 | 9.4 |
September | 4.6 | 13.5 | 17.7 | 19.6 | 15.7 | 15.8 | 8.9 | 8.3 | 9.0 |
Total/average | 211 | 178.1 | 144.5 | 19.5 | 18.6 | 18.5 | 7.8 | 8.3 | 9.4 |
Year | Irrigation Level | Plant Density | Kernel Number (103 Kernels m−2) | Kernel Weight (kg m−2) | Grain Yield (t ha−1) | ETa (mm) | WUE (kg m−3) | LAI |
---|---|---|---|---|---|---|---|---|
2016 | W1 | D1 | 4.3c | 1.61b | 16.4d | 556.2c | 2.95b | 5.7d |
D3 | 5.0b | 1.76a | 18.7a | 627.2b | 2.98a | 7.1c | ||
D4 | 5.0b | 1.74a | 18.4b | 625.4b | 2.94b | 7.6b | ||
D5 | 5.1a | 1.58b | 17.7c | 656.5a | 2.69c | 8.1a | ||
W2 | D1 | 4.7d | 1.79d | 18.3c | 657.5d | 2.79b | 6.2d | |
D3 | 5.5a | 2.04a | 20.6a | 720.2c | 2.86a | 7.6c | ||
D4 | 5.4b | 1.97b | 20.5a | 733.7b | 2.79b | 8.3b | ||
D5 | 5.3c | 1.87c | 20.0b | 776.2a | 2.57c | 8.9a | ||
W3 | D1 | 5.1d | 1.88c | 18.4d | 754.3d | 2.43c | 6.2d | |
D3 | 5.6c | 2.14b | 20.7b | 783.6c | 2.63a | 7.6c | ||
D4 | 6.3a | 2.22a | 21.0a | 797.8b | 2.64a | 8.5b | ||
D5 | 6.2b | 2.12b | 20.5c | 819.1a | 2.50b | 9.4a | ||
2017 | W1 | D1 | 4.7e | 1.67d | 16.3c | 589.9e | 2.76c | 5.6e |
D2 | 5.1d | 1.76c | 17.6b | 612.5d | 2.87b | 6.4d | ||
D3 | 5.7a | 1.95a | 18.6a | 626.6c | 2.97a | 7.3c | ||
D4 | 5.5b | 1.85b | 18.9a | 649.4b | 2.90b | 7.6b | ||
D5 | 5.4c | 1.74c | 17.8b | 664.5a | 2.69d | 8.4a | ||
W2 | D1 | 5.0d | 1.90c | 18.6d | 691.7e | 2.69c | 6.3e | |
D2 | 5.4c | 2.04b | 19.3c | 694.5d | 2.77b | 6.9d | ||
D3 | 5.9a | 2.13a | 20.8a | 725.5c | 2.86a | 7.8c | ||
D4 | 5.9a | 2.14a | 20.7ab | 736.0b | 2.81ab | 8.3b | ||
D5 | 5.7b | 2.03b | 20.4b | 780.0a | 2.61d | 9.2a | ||
W3 | D1 | 5.1d | 1.90d | 18.7d | 738.8e | 2.53b | 6.3e | |
D2 | 5.7c | 2.08c | 19.5c | 756.7d | 2.57b | 7.1d | ||
D3 | 6.2b | 2.16b | 20.8ab | 774.9c | 2.69a | 7.9c | ||
D4 | 6.3a | 2.32a | 21.2a | 784.1b | 2.70a | 8.7b | ||
D5 | 6.1b | 2.13b | 20.7b | 808.2a | 2.56b | 9.5a | ||
W4 | D1 | 5.0e | 1.91d | 18.6c | 784.5e | 2.37d | 6.3e | |
D2 | 5.6d | 2.03c | 19.6b | 796.0d | 2.46c | 7.3d | ||
D3 | 6.1c | 2.16b | 20.8a | 813.7c | 2.56a | 8.0c | ||
D4 | 6.3a | 2.31a | 21.0a | 824.3b | 2.55ab | 8.7b | ||
D5 | 6.2b | 2.14b | 20.8a | 831.3a | 2.50bc | 9.6a |
Sources of Variation | Kernel Number (103 kernels m−2) | Kernel Weight (kg m−2) | Grain Yield (t ha−1) | ETa (mm) | WUE (kg m−3) | LAI |
---|---|---|---|---|---|---|
2016 | ||||||
Irrigation level (W) | ** | ** | ** | ** | ** | ** |
Plant density (D) | ** | ** | ** | ** | ** | ** |
W × D | ** | ** | ** | ** | ** | ** |
2017 | ||||||
W | ** | ** | ** | ** | ** | ** |
D | ** | ** | ** | ** | ** | ** |
W × D | ** | ** | * | ** | ** | * |
Year (Y) | ** | ** | ** | ** | ns | ** |
Y × W | ** | * | ns | ** | ** | ns |
Y × D | ** | ** | ns | ** | ** | ** |
Y × W × D | ** | ** | * | ** | ** | ns |
Control Variable | Plant Density | LAI | Kernel Number | Kernel Weight | Grain Yield | |
---|---|---|---|---|---|---|
Irrigation level | Plant density | 1 | ||||
LAI | 0.984 ** | 1 | ||||
Kernel number | 0.736 ** | 0.782 ** | 1 | |||
Kernel weight | 0.443 * | 0.539 ** | 0.849 ** | 1 | ||
Grain yield | 0.670 ** | 0.744 ** | 0.803 ** | 0.861 ** | 1 |
Control Variable | Irrigation Level | LAI | Kernel Number | Kernel Weight | Grain Yield | |
---|---|---|---|---|---|---|
Plant density | Irrigation level | 1 | ||||
LAI | 0.872 ** | 1 | ||||
Kernel number | 0.772 ** | 0.790 ** | 1 | |||
Kernel weight | 0.761 ** | 0.867 ** | 0.936 ** | 1 | ||
Grain yield | 0.734 ** | 0.849 ** | 0.819 ** | 0.932 ** | 1 |
Year | Irrigation Level | Optimal Density (Plants m−2) | Optimum Yield (t ha–1) | 95% Confidential Interval |
---|---|---|---|---|
2016 | W1 | 11.1 | 18.7 | 1.3 |
W2 | 11.4 | 20.6 | 1.4 | |
W3 | 11.7 | 21.0 | 1.3 | |
2017 | W1 | 11.4 | 18.7 | 1.3 |
W2 | 12.0 | 20.7 | 0.9 | |
W3 | 12.2 | 21.0 | 1.1 | |
W4 | 12.2 | 20.9 | 1.1 |
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Zhang, G.; Ming, B.; Shen, D.; Xie, R.; Hou, P.; Xue, J.; Wang, K.; Li, S. Optimizing Grain Yield and Water Use Efficiency Based on the Relationship between Leaf Area Index and Evapotranspiration. Agriculture 2021, 11, 313. https://doi.org/10.3390/agriculture11040313
Zhang G, Ming B, Shen D, Xie R, Hou P, Xue J, Wang K, Li S. Optimizing Grain Yield and Water Use Efficiency Based on the Relationship between Leaf Area Index and Evapotranspiration. Agriculture. 2021; 11(4):313. https://doi.org/10.3390/agriculture11040313
Chicago/Turabian StyleZhang, Guoqiang, Bo Ming, Dongping Shen, Ruizhi Xie, Peng Hou, Jun Xue, Keru Wang, and Shaokun Li. 2021. "Optimizing Grain Yield and Water Use Efficiency Based on the Relationship between Leaf Area Index and Evapotranspiration" Agriculture 11, no. 4: 313. https://doi.org/10.3390/agriculture11040313