Effects of Controlled Release Urea Formula and Conventional Urea Ratio on Grain Yield and Nitrogen Use Efficiency of Direct-Seeded Rice
Abstract
:1. Introduction
2. Materials and Methods
2.1. Experiment Site and Materials
2.2. Experiment Design
2.3. Determinations of CRU Release Characteristics
2.4. Determinations of Tiller Number and NH4+-N Content
2.5. Determinations of Dry Weight, N Uptake and Their Translocation
2.6. Calculation of N Use Efficiency
2.7. Measurements of Grain Yield and Its Components
2.8. Data Statistical Analysis
3. Results
3.1. Cumulative Release Characteristics of CRU1 and CRU2 in the Paddy Field
3.2. Dynamics of Soil NH4+-N
3.3. Tiller Dynamics
3.4. Accumulation and Translocation of Dry Matter and N
3.5. N Use Efficiency
4. Discussion
4.1. Yield
4.2. N Use Efficiency
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Year | Treatment | 20 DAS | 30 DAS | 40 DAS | 50 DAS | 60 DAS | 70 DAS | 80 DAS | 90 DAS | 100 DAS | 110 DAS |
---|---|---|---|---|---|---|---|---|---|---|---|
2019 | BBU1 | 58.8 a | 48.6 a | 39.5 a | 29.3 a | 26.0 a | 18.3 a | 14.2 a | 13.1 a | 12.8 a | 12.5 a |
BBU2 | 54.3 b | 46.0 a | 36.5 a | 25.8 b | 25.0 a | 18.2 a | 13.9 a | 12.0 a | 11.7 a | 11.4 a | |
BBU3 | 50.4 c | 41.5 b | 32.9 b | 23.0 c | 23.3 b | 16.1 a | 13.1 a | 11.4 a | 11.2 a | 10.9 a | |
CK | 49.5 c | 43.3 b | 36.8 a | 27.0 b | 21.6 b | 21.0 a | 15.8 a | 12.8 a | 12.6 a | 12.4 a | |
2020 | BBU1 | 52.3 a | 46.7 a | 39.2 a | 30.2 a | 22 a | 14.5 a | 10.2 a | 10.4 a | 10.0 a | 9.7 a |
BBU2 | 47.0 b | 43.5 b | 35.3 b | 26.8 b | 21.3 a | 13.9 a | 10.4 a | 9.1 a | 8.8 a | 8.5 a | |
BBU3 | 43.7 c | 40.5 c | 33.1 b | 24.5 c | 17.8 b | 13.1 a | 9.4 a | 8.2 a | 7.8 a | 7.5 a | |
CK | 43.0 c | 42.2 b | 35.2 b | 27.5 b | 15.6 b | 15.9 a | 12.1 a | 10.4 a | 10.2 a | 10.0 a | |
ANOVA | Year | ** | * | NS | * | ** | ** | ** | ** | ** | ** |
Treatment | ** | ** | ** | ** | ** | NS | NS | NS | NS | NS | |
Year × Treatment | ** | * | NS | NS | NS | NS | NS | NS | NS | NS |
Year | Treatment | DWgrain (t ha−1) | DM (t ha−1) | DMT (t ha−1) | DMTE (%) | CDMRG (%) | ||
---|---|---|---|---|---|---|---|---|
Anthesis | Maturity | Post-Anthesis | ||||||
2019 | BBU1 | 8.6 a | 12.4 a | 20.1 a | 7.7 a | 2.7 ab | 22.3 b | 32.2 b |
BBU2 | 8.0 b | 11.2 b | 18.4 b | 7.2 bc | 2.6 b | 23.4 ab | 33.0 ab | |
BBU3 | 7.8 b | 10.9 b | 17.8 b | 6.9 c | 2.6 b | 23.9 a | 33.3 a | |
CK | 8.5 a | 12.1 a | 19.5 a | 7.3 ab | 2.8 a | 22.8 ab | 32.5 ab | |
2020 | BBU1 | 8.1 a | 11.8 a | 19.0 a | 7.3 a | 2.5 a | 21.5 ab | 31.1 ab |
BBU2 | 7.5 b | 10.8 c | 17.3 b | 6.6 b | 2.4 ab | 22.2 ab | 31.8 a | |
BBU3 | 7.4 b | 10.3 d | 16.5 b | 6.2 b | 2.3 b | 22.8 a | 31.9 a | |
CK | 8.0 a | 11.3 b | 18.3 a | 6.9 a | 2.4 ab | 21.3 b | 30.2 b | |
ANOVA | Year | ** | ** | ** | ** | NS | NS | NS |
Treatment | ** | ** | ** | ** | ** | * | ** | |
Year × Treatment | NS | NS | NS | NS | NS | NS | NS |
Year | Treatment | Ngrain (kg ha−1) | N Uptake (kg ha−1) | NT (kg ha−1) | NTE (%) | CNRG (%) | ||
---|---|---|---|---|---|---|---|---|
Anthesis | Maturity | Post-Anthesis | ||||||
2019 | BBU1 | 113.7 a | 179.5 a | 222.4 a | 42.9 a | 62.0 a | 34.5 b | 54.5 bc |
BBU2 | 101.5 b | 162.4 b | 203.3 b | 41.0 b | 58.1 bc | 35.7 ab | 57.1 a | |
BBU3 | 97.8 b | 152.8 c | 192.6 c | 39.8 b | 55.1 c | 36.1 a | 56.3 ab | |
CK | 114.8 a | 175.1 a | 217.1 a | 42.0 a | 60.7 ab | 34.7 b | 52.8 c | |
2020 | BBU1 | 118.4 a | 166.8 a | 211.7 a | 45.0 a | 65.9 a | 39.5 b | 55.7 ab |
BBU2 | 103.2 b | 148.6 b | 191.5 b | 42.9 bc | 59.1 b | 39.8 b | 57.3 a | |
BBU3 | 100.3 b | 140.1 b | 182.4 b | 42.3 c | 57.8 b | 41.3 a | 57.7 a | |
CK | 116.5 a | 160.8 a | 205.5 a | 44.8 ab | 63.4 a | 39.4 b | 54.5 b | |
ANOVA | Year | * | NS | ** | ** | ** | ** | NS |
Treatment | ** | * | ** | ** | ** | * | ** | |
Year × Treatment | NS | NS | NS | NS | NS | NS | NS |
Year | Treatment | Grain Yield (t ha−1) | Panicles (m−2) | Spikelets per Panicle | Spikelets (m−2) | Seed-Setting Rate (%) | 1000-Grain Weight (g) |
---|---|---|---|---|---|---|---|
2019 | N0 | 5.8 c | 316.1 d | 67.5 c | 21336.7 c | 88.2 a | 27.9 a |
BBU1 | 10.0 a | 453.5 a | 90.3 b | 40951.1 a | 87.5 a | 27.9 a | |
BBU2 | 9.3 b | 405.1 b | 92.2 ab | 37350.2 b | 87.1 a | 27.8 a | |
BBU3 | 9.1 b | 376.4 c | 93.2 ab | 35080.5 b | 87.9 a | 27.7 a | |
CK | 9.9 a | 401.8 b | 104.9 a | 42148.8 a | 87.5 a | 27.7 a | |
2020 | N0 | 5.4 c | 300.9 d | 72.8 b | 21905.1 d | 90.4 a | 27.6 a |
BBU1 | 9.5 a | 395.2 a | 98.4 a | 38887.7 a | 89.3 a | 27.7 a | |
BBU2 | 8.8 b | 365.6 b | 98.5 a | 36011.6 b | 89.3 a | 27.8 a | |
BBU3 | 8.6 b | 344.4 c | 98.2 a | 33820.1 c | 89.5 a | 28.2 a | |
CK | 9.3 a | 370.7 b | 109.2 a | 40480.4 a | 89.1 a | 27.5 a | |
ANOVA | Year | ** | ** | * | NS | NS | NS |
Treatment | ** | ** | ** | ** | NS | NS | |
Year×Treatment | NS | NS | NS | NS | NS | NS |
Year | Treatment | NRE (%) | NAE (kg N kg−1) | NPE (kg N kg−1) | DME (kg N kg−1) | GYE (kg N kg−1) | NHI (%) |
---|---|---|---|---|---|---|---|
2019 | BBU1 | 45.2 a | 15.2 a | 33.6 a | 89.7 a | 44.9 b | 53.7 a |
BBU2 | 37.7 b | 12.4 c | 32.8 a | 90.3 a | 45.7 b | 53.0 a | |
BBU3 | 34.3 b | 11.8 d | 34.4 a | 90.7 a | 47.1 a | 53.6 a | |
CK | 42.9 a | 14.4 b | 33.7 a | 89.0 a | 45.3 b | 55.9 a | |
2020 | BBU1 | 41.4 a | 15.7 a | 37.8 b | 90.3 b | 45.1 b | 53.2 a |
BBU2 | 34.3 bc | 12.9 c | 37.5 b | 90.3 b | 45.6 b | 50.7 a | |
BBU3 | 30.3 c | 12.3 c | 40.2 a | 92.2 a | 47.2 a | 52.1 a | |
CK | 39.5 a | 15.3 b | 38.7 ab | 89.6 b | 45.7 b | 53.7 a | |
ANOVA | Year | NS | ** | NS | NS | NS | NS |
Treatment | ** | ** | * | * | * | NS | |
Year × Treatment | NS | NS | NS | NS | NS | NS |
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Cheng, S.; Xing, Z.; Tian, C.; Li, S.; Tian, J.; Liu, Q.; Hu, Y.; Guo, B.; Hu, Q.; Wei, H.; et al. Effects of Controlled Release Urea Formula and Conventional Urea Ratio on Grain Yield and Nitrogen Use Efficiency of Direct-Seeded Rice. Agriculture 2022, 12, 1230. https://doi.org/10.3390/agriculture12081230
Cheng S, Xing Z, Tian C, Li S, Tian J, Liu Q, Hu Y, Guo B, Hu Q, Wei H, et al. Effects of Controlled Release Urea Formula and Conventional Urea Ratio on Grain Yield and Nitrogen Use Efficiency of Direct-Seeded Rice. Agriculture. 2022; 12(8):1230. https://doi.org/10.3390/agriculture12081230
Chicago/Turabian StyleCheng, Shuang, Zhipeng Xing, Chao Tian, Shaoping Li, Jinyu Tian, Qiuyuan Liu, Yajie Hu, Baowei Guo, Qun Hu, Haiyan Wei, and et al. 2022. "Effects of Controlled Release Urea Formula and Conventional Urea Ratio on Grain Yield and Nitrogen Use Efficiency of Direct-Seeded Rice" Agriculture 12, no. 8: 1230. https://doi.org/10.3390/agriculture12081230