Effects of water saving and nitrogen reduction on                         soil nitrate nitrogen distribution, water and nitrogen use efficiencies of                         winter wheat

AbstractThis study aims to investigate optimization of the basal-top-dressing nitrogen ratio for improving winter wheat grain yield, nitrogen use efficiency, water use efficiency and physiological parameters under supplemental irrigation. A water-saving irrigation (SI) regime was established and sufficient irrigation (UI) was used as a control condition. The split-nitrogen regimes used were based on a identical total nitrogen application rate of 240 kg ha−1 but were split in four different proportions between sowing and the jointing stage; i.e. 10:0 (N1), 7:3 (N2), 5:5 (N3) and 3:7 (N4). Compared with the N1, N2 and N4 treatments, N3 treatment increased grain yield, nitrogen and water use efficiencies by 5.27–17.75%, 5.68–18.78% and 5.65–31.02%, respectively, in both years. The yield advantage obtained with the optimized split-nitrogen fertilizer application may be attributable to greater flag leaf photosynthetic capacity and grain-filling capacity. Furthermore, the N3 treatment maintained the highest nitrogen and water use efficiencies. Moreover, we observed that water use efficiency of SI compared with UI increased by 9.75% in 2016 and 10.79% in 2017, respectively. It can be concluded that SI along with a 5:5 basal-top-dressing nitrogen ratio should be considered as an optimal fertigation strategy for both high grain yield and efficiency in winter wheat.

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Effect of nitrogen fertilizer rate on soil nitrate nitrogen content after harvesting winter wheat

The Journal of Agricultural Science ◽

10.1017/s0021859600072166 ◽

1990 ◽

Vol 114 (2) ◽

pp. 171-176 ◽

Cited By ~ 63

Author(s):

K. Chaney

Keyword(s):

Winter Wheat ◽

Nitrogen Content ◽

Nitrate Nitrogen ◽

Soil Horizon ◽

Fertilizer Treatment ◽

Soil Nitrate ◽

Fertilizer Rate ◽

Mineral N ◽

Nitrate N ◽

Nitrogen Fertilizer Rate

SUMMARYThe nitrate nitrogen content of the soil (0–90 cm) was measured immediately after the harvest of winter wheat at eight sites in central and eastern England in 1987 and 1988. On average, 50% of the total nitrate detected was in the 0–30 cm, 30% in the 30–60 cm and 20% in the 60–90 cm soil horizon. Although soil nitrate N increased with the amount of N fertilizer applied, it was not a linear relationship. There were small nonsignificant increases in soil nitrate up to the optimum fertilizer rate for yield but, once the optimum was reached, further addition of fertilizer increased nitrate contents significantly.Therefore, applying the correct quantity of N for high grain yield did not significantly increase soil nitrate residues after harvest compared with the no-fertilizer treatment. This emphasizes the importance of applying the appropriate rate of N for each crop, because applying too much is not only uneconomic but also significantly increases the amount of mineral N which could be subsequently leached over the winter.

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Soil Nitrate Nitrogen Content and Grain Yields of Organically Grown Cereals as Affected by a Strip Tillage and Forage Legume Intercropping

Plants ◽

10.3390/plants10071453 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1453

Author(s):

Aušra Arlauskienė ◽

Viktorija Gecaitė ◽

Monika Toleikienė ◽

Lina Šarūnaitė ◽

Žydrė Kadžiulienė

Keyword(s):

Winter Wheat ◽

Nitrogen Content ◽

Nitrate Nitrogen ◽

Soil Nitrate ◽

Forage Legume ◽

Forage Legumes ◽

Grain Yields ◽

Strip Tillage ◽

Perennial Legumes ◽

Strip Intercropping

Reducing tillage intensity and increasing crop diversity by including perennial legumes is an agrotechnical practice that strongly affects the soil environment. Strip tillage may be beneficial in the forage legume–cereals intercropping system due to more efficient utilization of biological nitrogen. Field experiments were conducted on a clay loam Cambisol to determine the effect of forage legume–winter wheat strip tillage intercropping on soil nitrate nitrogen (N-NO3) content and cereal productivity in various sequences of rotation in organic production systems. Forage legumes (Medicago lupulina L., Trifolium repens L., T. alexandrinum L.) grown in pure and forage legume–winter wheat (Triticum aestivum L.) strip tillage intercrops were studied. Conventional deep inversion tillage was compared to strip tillage. Nitrogen supply to winter wheat was assessed by the change in soil nitrate nitrogen content (N-NO3) and total N accumulation in yield (grain and straw). Conventional tillage was found to significantly increase N-NO3 content while cultivating winter wheat after forage legumes in late autumn (0–30 cm layer), after growth resumption in spring (30–60 cm), and in autumn after harvesting (30–60 cm). Soil N-NO3 content did not differ significantly between winter wheat strip sown in perennial legumes or oat stubble. Winter wheat grain yields increased with increasing N-NO3 content in soil. The grain yield was not significantly different when comparing winter wheat–forage legume strip intercropping (without mulching) to strip sowing in oat stubble. In forage legume–winter wheat strip intercropping, N release from legumes was weak and did not meet wheat nitrogen requirements.

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Evaluating Different Non-Destructive Estimation Methods for Winter Wheat (Triticum aestivum L.) Nitrogen Status Based on Canopy Spectrum

Remote Sensing ◽

10.3390/rs12010095 ◽

2019 ◽

Vol 12 (1) ◽

pp. 95 ◽

Cited By ~ 1

Author(s):

Hongjun Li ◽

Yuming Zhang ◽

Yuping Lei ◽

Vita Antoniuk ◽

Chunsheng Hu

Keyword(s):

Winter Wheat ◽

Nitrate Nitrogen ◽

Vegetation Indices ◽

Estimation Methods ◽

Estimation Accuracy ◽

Soil Nitrate ◽

Nitrogen Status ◽

Non Destructive ◽

Estimation Models ◽

Multispectral Camera

Compared to conventional laboratory testing methods, crop nitrogen estimation methods based on canopy spectral characteristics have advantages in terms of timeliness, cost, and practicality. A variety of rapid and non-destructive estimation methods based on the canopy spectrum have been developed on the scale of space, sky, and ground. In order to understand the differences in estimation accuracy and applicability of these methods, as well as for the convenience of users to select the suitable technology, models for estimation of nitrogen status of winter wheat were developed and compared for three methods: drone equipped with a multispectral camera, soil plant analysis development (SPAD) chlorophyll meter, and smartphone photography. Based on the correlations between observed nitrogen status in winter wheat and related vegetation indices, green normalized difference vegetation index (GNDVI) and visible atmospherically resistant index (VARI) were selected as the sensitive vegetation indices for the drone equipped with a multispectral camera and smartphone photography methods, respectively. The correlation coefficients between GNDVI, SPAD, and VARI were 0.92 ** and 0.89 **, and that between SPAD and VARI was 0.90 **, which indicated that three vegetation indices for these three estimation methods were significantly related to each other. The determination coefficients of the 0–90 cm soil nitrate nitrogen content estimation models for the drone equipped with a multispectral camera, SPAD, and smartphone photography methods were 0.63, 0.54, and 0.81, respectively. In the estimation accuracy evaluation, the method of smartphone photography had the smallest root mean square error (RMSE = 9.80 mg/kg). The accuracy of the smartphone photography method was slightly higher than the other two methods. Due to the limitations of these models, it was found that the crop nitrogen estimation methods based on canopy spectrum were not suitable for the crops under severe phosphate deficiency. In addition, in estimation of soil nitrate nitrogen content, there were saturation responses in the estimation indicators of the three methods. In order to introduce these three methods in the precise management of nitrogen fertilizer, it is necessary to further improve their estimation models.

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Water-saving irrigation practices for rice yield information and nitrogen use efficiency under sub-tropical monsoon climate

Water Science & Technology Water Supply ◽

10.2166/ws.2019.133 ◽

2019 ◽

Vol 19 (8) ◽

pp. 2485-2493 ◽

Cited By ~ 1

Author(s):

Zheng Huabin ◽

Zhou Wei ◽

Chen Qimin ◽

Chen Yuanwei ◽

Tang Qiyuan

Keyword(s):

Nitrogen Use Efficiency ◽

Water Saving ◽

Rice Production ◽

Production Model ◽

Nitrogen Use ◽

Nitrogen Reduction ◽

Production Models ◽

Significant Difference ◽

Use Efficiency ◽

Irrigation Practices

Abstract Simple and practical water-saving irrigation practices (WIP) with nitrogen-reduction are beneficial to the development of rice cultivation technology with promotion of resource-conservation and environmental friendliness. The effects of WIP with nitrogen-reduction on population quality, annual yield and nitrogen use efficiency were studied by a field experiment. WIP could maintain or increase the annual yield of rice production models. The highest annual yield of more-water-saving irrigation practice (WIP150) was 8.42 t hm−2 for the double-season rice production model and 12.71 t hm−2 for the ratoon rice production model, respectively. Compared with non-application of nitrogen, the annual yield of nitrogen-reducing practice (NRP) and farms' fertilizer practice (FFP) increased significantly (p < 0.01), while a non-significant difference of annual yield between the FFP and NRP was observed; the annual yield of the NRP and FFP was 9.73 and 10.02 t hm−2 of the double-season rice production model, and 12.84 and 14.34 t hm−2 of the ratoon rice production model, respectively. AEN, PEN, PFPN and RUEN of the NRP were higher than those of the FFP. Therefore, observing the change of water layer in the soil layer via a simple self-made PVC indicator tube, reducing about 20% nitrogen quantity was a feasible and simple cultivation technique for water-saving and nitrogen-reduction in the rice production models.

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