Layered nitrogen application technology for dry alkaline wheat and application of layered nitrogen application technology

Abstract

The invention discloses a dry alkali wheat layered nitrogen application technology and application, and belongs to the technical field of crop fertilization. The layering is divided into two layers, the first layer adopts a conventional base fertilizer applying mode, except for the potassium fertilizer and the phosphate fertilizer, the applying amount of the nitrogen fertilizer is 55-60% of the total amount of the nitrogen fertilizer, and the depth is 8-10 cm; only nitrogen fertilizer is applied to the second layer, the fertilizing amount is 40-45% of the total amount of the nitrogen fertilizer, a slow-release fertilizing mode is adopted, and the depth is 25-35 cm. Wherein the slow-release fertilization mode comprises a coated urea form, the coated urea contains a nitrification inhibitor, and the final concentration of the nitrification inhibitor is 1% of the nitrogen content. All the fertilizers are applied before sowing, topdressing is not needed, and the method that different depths are matched with slow release is more suitable for the growth requirements of the drought alkaline wheat. The method has the advantages that the wheat yield is high, the fertilizer utilization rate is greatly increased, the production cost is greatly reduced, the problem of waterless topdressing difficulty in spring is solved, soil is deeply scarified, the saline-alkali soil structure is improved, and resource waste and environmental pollution are effectively avoided.

Description

Technical Field

[0001] This invention belongs to the field of crop fertilization technology, and in particular relates to a stratified nitrogen application technology and its application for drought-resistant and alkaline wheat. Background Technology

[0002] Nitrogen fertilizer management plays a crucial role in coordinating nitrogen supply during the wheat's growth period, regulating wheat population structure, promoting nitrogen accumulation and translocation, and increasing yield. Dryland wheat, with its long growth period (generally around 240-250 days), is prone to nutrient deficiency in the later stages of growth, making spring topdressing essential. Dryland wheat production is subject to drought stress, especially in most parts of North China where spring droughts are common. In dryland wheat production areas, irrigation facilities are largely lacking, making effective spring topdressing impossible. Common methods include surface application, furrow application, or water-soluble fertilizer application, which result in low fertilizer utilization, increased production costs, and high technical and equipment requirements. These methods often fail to achieve the desired topdressing effect, leading to either blindly increasing the amount of fertilizer or causing severe nutrient deficiency later in the growth cycle, thus affecting yield. Alternatively, a "one-shot" fertilization method, where all fertilizer is applied at once and superficially, fails to meet the needs of the deep root system of wheat and leads to nutrient volatilization and loss, reducing efficiency and polluting the environment. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a layered nitrogen application technology and its application for drought-resistant and alkaline wheat. This invention involves layering and deep application of fertilizer, with a special formula used for the deep-application fertilizer (e.g., urea coating plus inhibitors). The first layer of fertilizer is a conventional base fertilizer, applied at a depth of 8-10 cm. The second layer of fertilizer is applied deep at a depth of 30 cm. Utilizing the low temperatures of winter and the use of slow-release materials and inhibitors, the fertilizer takes effect after the wheat greens up in spring.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] One objective of this invention is to provide a method for applying nitrogen in layers to drought-resistant and alkaline wheat. The layering involves two layers: the first layer uses conventional basal fertilizer application, with the amount of fertilizer being 55-60% of the total nitrogen fertilizer and a depth of 8-10 cm; the second layer uses slow-release fertilizer application, with the amount of fertilizer being 40-45% of the total nitrogen fertilizer and a depth of 25-35 cm.

[0006] Furthermore, the method also includes the combined application of phosphate and potassium fertilizers.

[0007] Furthermore, the total application rate of nitrogen, phosphorus, and potassium in the method is: 13.4 kg of nitrogen, 9.2 kg of phosphorus, and 2.8 kg of potassium per mu.

[0008] Furthermore, the phosphorus and potassium fertilizers are applied to the first layer using conventional basal fertilizer application methods.

[0009] Furthermore, the slow-release fertilization method includes coated urea, which contains an inhibitor.

[0010] Furthermore, the inhibitors include nitration inhibitors.

[0011] Furthermore, the final concentration of the nitrification inhibitor is 1% of the nitrogen content.

[0012] Furthermore, the method also includes the use of furrow-ridge tillage technology; the furrow refers to a sowing furrow, 12cm wide and 7-10cm deep; the ridge refers to a ridge 20cm wide formed between the furrows.

[0013] The second objective of this invention is to provide an application of the aforementioned stratified nitrogen application method for drought-resistant and alkaline wheat in wheat cultivation.

[0014] Furthermore, the application can eliminate the need for topdressing in wheat cultivation, which can save costs, solve the problem of difficulty in topdressing in spring when there is no water, loosen the soil, improve the soil structure of saline-alkali land, and the furrows and ridges can also prevent salt from entering the soil.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] I. This invention fully verifies through two sets of experiments that the stratified nitrogen application method for drought-resistant and alkaline wheat in this invention can significantly increase wheat yield:

[0017] 1. The first experiment consisted of 6 experimental groups: M1 No fertilizer. M2 NPK fertilizer was applied as a single basal application in the form of compound fertilizer, at a depth of 10cm. M3 PK fertilizer and 57% NPK fertilizer were applied as a basal application in the form of compound fertilizer, at a depth of 10cm; 43% NPK fertilizer was applied as a top dressing in the form of urea during the greening period. M4 PK fertilizer and 57% NPK fertilizer were applied as a basal application in the form of compound fertilizer, at a depth of 10cm; 43% NPK fertilizer was applied as a top dressing in the form of urea 30cm deep before sowing. M5 PK fertilizer and 57% NPK fertilizer were applied as a basal application in the form of compound fertilizer, at a depth of 10cm; 43% NPK fertilizer was applied as a top dressing in the form of polyurethane-coated urea (containing nitrification inhibitors, with a final concentration of 1% of the nitrogen content) 30cm deep before sowing. M6 PK fertilizer and 57% NPK fertilizer were applied as a basal application in the form of compound fertilizer, at a depth of 10cm; 43% NPK fertilizer was applied as a top dressing in the form of urea-formaldehyde 30cm deep before sowing. Among them:

[0018] (1) The results of population dynamics of wheat at different growth stages showed that there was no significant difference in the number of wheat populations among the treatments at the emergence stage. After entering the tillering stage, differences appeared in the treatments and reached a significant level. Before winter, the number of tillers per plant was M2>M6>M5>M4>M3>M1 in Cangmai 6002, while it was M2>M4>M6>M5>M3>M1 in Jiemai 19. The largest population size of both varieties occurred in the M2 treatment at the jointing stage, followed by the M3 treatment. The other treatments showed different results among different varieties. In Jiemai 19, it was M4>M5>M6>M1, while in Cangmai 6002 it was M5>M4>M1>M6. After the jointing stage, the population size of each treatment began to decline. During the grain-filling stage, the population size of Jiemai 19 showed the order of M3>M5>M2>M4>M6>M1, while that of Cangmai 6002 showed the order of M5>M3>M4>M2>M6>M1. The ear-bearing rate of the M2 treatment was significantly lower than that of other treatments by 10.83%-25.43% in both varieties. This indicates that the population increase from a single basal application of fertilizer at the jointing stage is mostly ineffective tillering, which is detrimental to yield formation. Stratified fertilization is beneficial for establishing a reasonable population size during the wheat growth period, promoting ear formation, and laying the foundation for high and stable yields.

[0019] (2) Effects of different treatments on flag leaf area and chlorophyll content during the grain-filling stage of wheat: The results showed that the fertilization method had a significant effect on the SPAD value and leaf area of ​​the flag leaf during the grain-filling stage of both wheat varieties. The SPAD value of the flag leaf during the grain-filling stage of Cangmai 6002 wheat was M3>M4>M5>M2>M6>M1, among which the differences between M3, M4, M5 and M1, M2, M6 reached a significant level; the SPAD value of the flag leaf during the grain-filling stage of Jiemai 19 was M3>M5>M6>M4>M2>M1, among which the differences between M3 and M2, and between M6, M5, M4, M3, M2 and M1 reached a significant level. The flag leaf area of ​​Cangmai 6002 during the grain-filling stage was M3>M4>M5>M6>M2>M1, while that of Jiemai 19 was M3>M5>M4>M2>M6>M1. The maximum leaf area for both varieties was observed in the M3 treatment, with significant differences compared to the M1 and M2 treatments. Significant differences compared to the M4 treatment were only observed in Jiemai 19, while no significant differences were observed between the M4 and M5 treatments in either variety. Nitrogen, a mineral element crucial for plant growth, plays a vital role in leaf morphology and chlorophyll content. Compared to a single basal application of fertilizer, topdressing during the jointing stage and stratified fertilization can effectively increase the flag leaf area and chlorophyll content of wheat while maintaining a constant total nitrogen supply.

[0020] (3) Effects of different treatments on the photosynthetic rate of flag leaves during the grain-filling stage of wheat: The photosynthetic rate of flag leaves of Cangmai 6002 14 days after flowering was: M3>M5>M4>M6>M1>M2; the photosynthetic rate of flag leaves 28 days after flowering was: M5>M4>M6>M3>M1>M2. The photosynthetic rate of flag leaves of Jiemai 19 14 days after flowering was: M3>M5>M4>M6>M2>M1; the photosynthetic rate of flag leaves 28 days after flowering was: M5>M4>M3>M6>M2>M1. Nitrogen plays an important role in improving the photosynthetic rate of plant leaves. The experimental results showed that compared with the single basal application of fertilizer, topdressing at the jointing stage and deep application of nitrogen fertilizer mixed with inhibitors can significantly improve the photosynthetic rate of flag leaves in the early grain-filling stage of wheat; while deep application of nitrogen fertilizer and deep application of nitrogen fertilizer mixed with inhibitors in the late grain-filling stage can effectively delay the senescence of functional leaves and improve the grain-filling rate.

[0021] (4) Dynamic changes in grain dry weight accumulation of different wheat varieties under different treatments: The dynamic changes in grain dry weight accumulation of different wheat varieties under different treatments all showed an "S"-shaped curve, including three stages: a gradual increase period, a rapid increase period, and a slow increase period. That is, the grain filling rate increased slowly from 7 to 14 days after flowering; the grain filling rate increased rapidly from 14 to 21 days after flowering and reached its maximum value during this period; the grain filling rate decreased rapidly from 28 to 35 days after flowering and was in the slow increase period again. Fitting results of the grain filling process of wheat under each treatment showed that fertilization treatment prolonged the grain filling duration and effective grain filling duration of wheat, and increased the maximum grain filling rate and theoretical maximum thousand-grain weight. The combined results showed that, under the same nitrogen application level, compared with single-layer basal application of nitrogen fertilizer and topdressing during the greening period, layered application of nitrogen fertilizer effectively prolonged the grain filling duration and effective grain filling duration of wheat and increased the theoretical maximum thousand-grain weight.

[0022] (5) Effects of different treatments on wheat yield and its components: The results showed that each treatment had different effects on the yield and yield components of different drought-resistant wheat varieties. The number of grains per spike in Cangmai 6002 was M5>M4>M2>M3>M6>M1, with significant differences between treatments M5 and M4 and treatments M1, M3, and M6. The number of grains per spike in Jiemai 19 was M3>M4>M5>M6>M2>M1, with significant differences between treatment M3 and treatments M1, M2, and M6. Compared with no fertilization and one-time shallow fertilization, the effect of layered fertilization with mixed inhibitors and topdressing during the greening period was obvious. The maximum number of spikes per mu for the two varieties appeared in treatments M3 (Cangmai 6002) and M5 (Jiemai 19), respectively. There was no significant difference in the number of spikes per mu between the two treatments in the two varieties, and both were significantly higher than treatments M1 and M2. The maximum thousand-grain weight of Cangmai 6002 was 38.72 g in treatment M4, while the maximum thousand-grain weight of Jiemai 19 was 40.55 g in treatment M3. The maximum yield of Cangmai 6002 was 391.04 kg / mu in treatment M5, representing a significant increase of 28.93%, 8.37%, and 12.03% compared to treatments M1, M2, and M6, respectively. However, the yield difference with treatments M3 and M4 was not significant. Similarly, the maximum yield of Jiemai 19 was 381.53 kg / mu in treatment M3, representing a significant increase of 30.51%, 19.91%, 10.84%, and 22.63% compared to treatments M1, M2, M4, and M6, respectively. The yield difference with treatment M5 was not significant, but the yield differences between treatment M5 and treatments M1, M2, and M6 were also significant. This indicates that compared to a single-layer basal application of nitrogen fertilizer, topdressing during the greening period, deep application of nitrogen fertilizer, and deep application of nitrogen fertilizer mixed with inhibitors can all effectively increase wheat yield. Among them, deep application of nitrogen fertilizer mixed with inhibitors and topdressing during the greening period have a better yield-increasing effect than deep application of nitrogen fertilizer, while deep application of urea-formaldehyde has no significant effect on yield increase.

[0023] (6) The dry matter translocation of the two wheat varieties under different treatments and their contribution to grain yield showed that: in Cangmai 6002, the pre-flowering dry matter translocation of each treatment was M3>M5>M4>M2>M6>M1, with M3 and M5 treatments significantly increasing by 11.90% and 7.81% respectively compared to M2; in Jiemai 19, the pre-flowering dry matter translocation of each treatment was M5>M4>M3>M6>M2>M1, with M5 treatment significantly increasing by 10.16% compared to M2; the contribution rate of pre-flowering dry matter to grain yield of the two varieties was 19.47%-21.66% (Cangmai 6002) and 17.97%-20.80% (Jiemai 19). In Cangmai 6002, the post-flowering dry matter translocation of each treatment showed the order M3>M5>M4>M2>M6>M1, with treatments M5, M4, and M3 showing a significant increase of 8.19%-18.92% compared to M2. In Jiemai 19, the post-flowering dry matter translocation of each treatment also showed the order M3>M5>M4>M6>M2>M1, with treatments M5, M4, and M3 showing a significant increase of 8.99%-17.90% compared to M2. The contribution rate of post-flowering dry matter production to grain yield for the two varieties was 78.34%-80.52% (Cangmai 6002) and 79.19%-81.26% (Jiemai 19), respectively. This indicates that topdressing during the greening stage, deep application of nitrogen fertilizer, and deep application of nitrogen fertilizer mixed with inhibitors can all effectively increase the post-flowering dry matter accumulation in wheat.

[0024] (7) The effects of different treatments on nitrogen accumulation and translocation in wheat showed that nitrogen accumulation in wheat mainly originated from pre-flowering, with pre-flowering nitrogen accumulation accounting for 77% to 90% of total nitrogen accumulation. The changes in pre- and post-flowering nitrogen accumulation and grain nitrogen accumulation were basically consistent between the two varieties in each treatment, showing the order M5>M3>M4>M2>M6>M1. In Jiemai 19, the grain nitrogen accumulation in the M4 treatment was significantly increased by 7.08% compared to M2. In Cangmai 6002, the post-flowering nitrogen accumulation and post-flowering nitrogen translocation in the M4 treatment were significantly increased by 8.50% and 39.68% respectively compared to M2. Therefore, it can be concluded that compared to the "one-shot" nitrogen application at sowing, the higher grain nitrogen accumulation from stratified nitrogen application may originate from post-flowering nitrogen accumulation and translocation. Compared to the M4 treatment, the M3 treatment showed increased nitrogen accumulation before and after flowering, increased nitrogen translocation after flowering, and increased grain nitrogen accumulation, with significant differences observed in 6002. In contrast, compared to the M5 treatment, all of these indicators decreased, with significant differences observed in Jiemai 19. Furthermore, compared to M5, M3 and M4 showed a higher contribution rate of nitrogen translocation to grain production, while M3 and M4 showed a lower contribution rate. This indicates that deep application of nitrogen fertilizer is more beneficial for increasing nitrogen accumulation in vegetative organs after flowering, rather than in grain production, compared to topdressing during the greening stage.

[0025] (8) The effects of different treatments on the nitrogen fertilizer utilization efficiency of wheat showed that the nitrogen fertilizer absorption and utilization rate of both wheat varieties was M5>M3>M4>M2>M6; in Jiemai 19, the nitrogen fertilizer absorption and utilization rate of the M5 treatment was significantly higher than that of the other treatments, while in Cangmai 6002 there was no significant difference from the M3 treatment. In both varieties, the nitrogen fertilizer absorption and utilization rate of the M3 treatment was significantly higher than that of M2 and M4, while the fertilizer absorption and utilization rate of the M4 treatment was only significantly different from that of M2 in Cangmai 6002. For Cangmai 6002, the nitrogen fertilizer agronomical utilization rate and nitrogen fertilizer partial productivity were both M5>M3>M4>M2>M6, with the M5 treatment showing a significant increase in nitrogen fertilizer agronomical utilization rate of 8.43% compared to the M2 treatment. For Jiemai 19, the nitrogen fertilizer agronomical utilization rate and nitrogen fertilizer partial productivity were M3>M5>M4>M2>M6, with the M3 and M5 treatments showing significant increases in nitrogen fertilizer agronomical utilization rate of 19.79% and 15.69% respectively compared to the M2 treatment, and the M3 treatment showing a significant increase in nitrogen fertilizer agronomical utilization rate of 10.72% compared to the M4 treatment. The harvest index among treatments of Cangmai 6002 was M5>M4>M6>M3>M2>M1, and the harvest index among treatments of Jiemai 19 was M5>M4>M3>M2>M6>M1. The differences in M5, M3, M4, M2 and M1 among treatments within both varieties were significant, indicating that fertilization treatment is beneficial to increasing the harvest index of wheat. In Cangmai 6002, the harvest index of treatments M4 and M5 increased significantly by 8.47% and 13.59% compared with M2, respectively. In Jiemai 19, the harvest index of treatments M4 and M5 increased significantly by 1.43% and 5.07% compared with M2, respectively. This indicates that compared with the "one-shot" nitrogen application at sowing, deep application of nitrogen fertilizer and deep application of nitrogen fertilizer mixed with inhibitors can effectively promote the transport of wheat photosynthetic assimilates to grains and improve the wheat harvest index. The harvest index of treatment M5 was significantly higher than that of treatment M3 in Cangmai 6002 by 9.92%, but the difference in Jiemai 19 was not significant.

[0026] (9) The results of soil mineral nitrogen content in 0-60cm of each treatment showed that, overall, soil mineral calcium content decreased with the progress of wheat growth and the increase of vertical depth. Before wintering, the soil mineral nitrogen content in 0-20cm of soil was M2>M3>M4>M5>M1, with M2 treatment showing a significant increase of 11.37%-22.89% compared to other treatments, while the differences among the other treatments were not significant. At the jointing stage, the soil mineral nitrogen content in 0-20cm of soil was M3>M4>M2>M5>M1, with M3 treatment showing a significant increase of 11%-32% compared to other treatments, and M4 treatment showing a significant increase of 13%-17% compared to M1, M2, and M5. At the maturity stage, there was no significant difference in soil mineral nitrogen content in 0-20cm of soil among the treatments. During the wheat growing season, the change in soil mineral nitrogen content in 0-20cm of soil was M2>M3>M4>M1>M5. Before overwintering, the mineral nitrogen content in the 20-40cm soil layer showed the order M4>M2>M5>M3>M1. At the jointing stage, the order was M3>M4>M5>M2>M1. At maturity, the order was M5>M4>M3>M2>M1. The M5 treatment showed a significant increase in mineral nitrogen content compared to the M1 and M2 treatments, by 14.83 and 28.10, respectively. Before overwintering, the mineral nitrogen content in the 40-60cm soil layer showed the order M4>M2>M5>M3>M1. At the jointing stage, the order was M3>M5>M4>M2>M1. At maturity, the order was M5>M2>M4>M3>M1. Overall, the decrease coefficient of mineral nitrogen in each soil layer (0-60cm) tended to be stable during the wheat growth period, indicating that the distribution of mineral nitrogen in each soil layer under natural conditions was mainly affected by leaching. Layered fertilization and topdressing during the greening stage significantly increased the mineral nitrogen content in the soil layer adjacent to the fertilizer application during the growing season. At this time, the distribution of soil mineral nitrogen was mainly affected by fertilizer hydrolysis and nitrification. During the wheat growth period, the mineral nitrogen content in the 20-60cm soil layer of the M5 treatment was relatively stable and significantly higher than other treatments at the maturity stage, indicating that deep application of inhibitors prolonged the fertilizer release cycle, ensuring sufficient nitrogen supply during the wheat growth period and laying the foundation for increased yield. Correlation analysis showed that the mineral nitrogen content in the 20-40cm soil layer during the jointing stage was significantly correlated with the number of wheat ears per mu (unit of land area). The mineral nitrogen content in the 20-60cm soil layer during the jointing stage significantly affected the pre-flowering nitrogen accumulation and translocation of wheat, thus affecting wheat yield. The mineral nitrogen content in the 0-60cm soil layer during the maturity stage significantly affected the yield components, yield, and grain nitrogen accumulation of wheat. The mineral nitrogen content in the 20-40cm soil layer during the maturity stage was significantly positively correlated with the post-flowering nitrogen accumulation. Therefore, sufficient nutrient supply is beneficial to wheat yield formation.

[0027] 2. The second experiment was conducted in four groups: M1: 57% nitrogen and phosphorus-potassium fertilizer were applied as a basal fertilizer before sowing, and 43% nitrogen fertilizer was applied as polyurethane-coated urea, at a depth of 10cm. M2: 57% nitrogen and phosphorus-potassium fertilizer were applied as a basal fertilizer before sowing; 43% nitrogen fertilizer was applied as polyurethane-coated urea at a depth of 25cm before sowing. M3: 57% nitrogen and phosphorus-potassium fertilizer were applied as a basal fertilizer before sowing; 43% nitrogen fertilizer was applied as polyurethane-coated urea at a depth of 30cm before sowing. M4: 57% nitrogen and phosphorus-potassium fertilizer were applied as a basal fertilizer before sowing; 43% nitrogen fertilizer was applied as polyurethane-coated urea at a depth of 35cm before sowing. (Note:)

[0028] (1) Effects of different treatments on flag leaf physiological characteristics and photosynthetic performance: The results showed that the flag leaf area of ​​the M3 treatment during the grain-filling period was the largest at 33.77 cm, which was significantly higher than that of the M1 treatment by 18.23%, indicating that 30 cm deep fertilization can support a larger canopy photosynthetic area. The SPAD value of the M3 treatment during the grain-filling period reached 49.15, which was significantly higher than that of other treatments by 7.64%-23.02%; the differences between the M2 and M4 treatments and the M1 treatment were also significant, indicating that deep fertilization can delay leaf senescence. The photosynthetic rate was positively correlated with the SPAD value, and the photosynthetic rate of the M3 treatment during the grain-filling period was 29.44 μmol / (m²). 2 ·s), which is 24.64% higher than M1.

[0029] (2) Effects of different treatments on the distribution of available nitrogen in the soil: There was no significant difference in the available nitrogen content in the 0-40cm soil layer among the treatments at the jointing stage; the available nitrogen content in the 0-40cm soil layer at the flowering stage was M3 > M2 > M4 > M1, and the available nitrogen content in the 0-40cm soil layer at the grain-filling stage was M3 > M4 > M2 > M1. The available nitrogen content in the 0-40cm soil layer at the flowering and grain-filling stages of the M3 treatment was 72.34 mg / kg and 66.84 mg / kg, respectively, which were significantly higher than those of the M1 treatment by 10.73% and 27.55%. This indicates that the stratified deep application of nitrogen fertilizer at a depth of 30cm can optimize the vertical distribution of nitrogen, prolong the nitrogen supply capacity in the later stages of wheat growth, and reduce nitrogen loss in the surface layer.

[0030] (3) The results of the effects of different treatments on wheat yield showed that the yield of each treatment was M3 > M2 > M4 > M1. Among them, the M3 treatment had the highest yield of 371.93 kg / mu, which was significantly higher than the M1 treatment by 27.98% and M4 treatment by 8.28%, respectively. The increase in yield was mainly due to the synergistic increase in the number of ears per mu and the number of grains per ear. The M2 and M4 treatments also significantly increased the yield by 21.57% and 18.19% compared with the M1 treatment, respectively. This indicates that the stratified deep application of nitrogen fertilizer can optimize the nutrient supply during ear differentiation and grain filling, thereby increasing wheat yield.

[0031] (4) Effects of different treatments on wheat water and fertilizer use efficiency: The results showed that the nitrogen fertilizer use efficiency and water use efficiency of each treatment were M3 > M2 > M4 > M1. Among them, the nitrogen fertilizer use efficiency of treatment M3 was 27.47 kg / kg, which was significantly higher than that of treatment M1 by 27.98%; the water use efficiency was 13.04 ± 0.93 kg / (hm). 2 The nitrogen fertilizer application rate (*mm) was significantly higher than that of the M1 treatment by 22.09%, indicating that stratified deep application of nitrogen fertilizer can improve the efficiency of wheat resource utilization.

[0032] The second experiment showed that layered deep application of nitrogen fertilizer can effectively prolong nitrogen supply in the later stages of growth, increase the SPAD value and photosynthetic rate of flag leaves during the grain-filling period of wheat, promote the increase of the number of ears per mu and the number of grains per ear, thereby significantly increasing yield and improving water and fertilizer use efficiency. However, if the deep application depth is too deep (35cm), it will lead to increased root absorption resistance, which is not conducive to the formation of wheat yield. Therefore, the depth of layered deep application of nitrogen fertilizer for wheat should be 30cm.

[0033] 3. The layered nitrogen application method for drought-resistant and alkaline wheat in this invention can also significantly reduce wheat planting costs: The cost of agricultural machinery for topdressing in spring is 10 yuan per mu, the labor cost is 10 yuan, and the fertilizer cost is 25 yuan, totaling 45 yuan. The method in this invention can eliminate the costs of agricultural machinery and labor for topdressing, and the fertilizer cost is 35 yuan. Under the premise that the yield difference is not significant, 10 yuan is saved per mu.

[0034] In summary, all fertilizers in this invention are applied before sowing, avoiding the need for later topdressing. Furthermore, the combination of slow-release methods at different depths is more suitable for the growth needs of drought-tolerant wheat. Using the methods in this invention not only increases wheat yield but also significantly improves fertilizer utilization, greatly reduces production costs, and effectively avoids resource waste and environmental pollution.

[0035] Second, the drought-resistant and alkaline wheat stratified nitrogen application method in this invention, combined with the furrow and ridge tillage technology, can effectively avoid salt and collect rainwater, thereby increasing soil moisture content.

[0036] Third, in response to the layered nitrogen application method for drought-resistant and alkaline wheat in this invention, the inventors have also developed a brand-new agricultural machine that can apply fertilizer in layers, achieving the effect of layered fertilization in one step. Attached Figure Description

[0037] Figure 1 This illustrates the dynamic changes in grain dry weight accumulation of different wheat varieties under different treatments in Example 1 of the present invention.

[0038] Figure 2 This refers to the dry matter translocation of two types of wheat under different treatments in Example 1 of the present invention and their contribution to grain yield.

[0039] Figure 3This illustrates the effects of different treatments on nitrogen accumulation and translocation in wheat in Example 1 of the present invention.

[0040] Figures 4-5 The mineralized nitrogen content of soil in the 0-60cm depth for each treatment in Example 1 of this invention;

[0041] Figure 6 This illustrates the effect of furrowing and ridge planting on the soil salinity in the 0-5cm depth during embodiment 3 of the present invention.

[0042] Figure 7 This illustrates the effect of furrowing and ridge planting on soil moisture in the 0-10cm depth in Example 3 of this invention.

[0043] Figure 8 This is a field planting effect diagram of Embodiment 3 of the present invention. Detailed Implementation

[0044] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the invention. Any modifications or substitutions made to the methods, steps, or conditions of the present invention without departing from the spirit and essence of the invention are within the scope of the invention. The reagents and instruments used in the following examples are commercially available, and the methods used in the examples, unless otherwise specified, are consistent with conventional methods.

[0045] The nitration inhibitor used in this invention, n-butylthiophosphoric triamine (CAS94317-64-3), was purchased from Hubei Jiahuixingcheng Biotechnology Co., Ltd.

[0046] The technical solution of the present invention will be further described in detail below with reference to the embodiments.

[0047] Example 1

[0048] This experiment aims to use Jiemai 19 and Cangmai 6002 as test subjects to investigate the effects of fertilizer stratification and the combined application of fertilizer inhibitors with nitrogen (13.4 kg / mu), phosphorus (9.2 kg / mu), and potassium (2.8 kg / mu) on fertilizer utilization efficiency in wheat fields. Under the framework of a simplified wheat production model, this study seeks to optimize the fertilization method for dryland winter wheat and improve wheat yield and fertilizer utilization efficiency.

[0049] 1. Materials and Methods

[0050] 1.1 Experimental Design

[0051] This experiment aims to observe two fertilization varieties, Jiemai 19 and Cangmai 6002, and five fertilization treatments (as shown in Table 1), for a total of 10 treatments, with three replicates and a plot area of ​​13.5 m². 2(3m × 4.5m), arranged in a randomized block design, sown evenly in wide furrows, furrow depth 7 cm, furrow width 12 cm, ridges formed on the sides of the furrows, ridge width 20 cm, seeds sown evenly in the furrows, covered with 2 cm of soil, seeding density 17.5 kg / mu. Conventional field management. Soil properties before sowing were pH 7.86, organic matter content 8.60 g·kg -1 , total salt content 0.20%, total nitrogen content 0.14 g·kg -1 , available nitrogen content 74.26 mg·kg -1 , total phosphorus content 0.25 g·kg -1 , available phosphorus content 1920.97 mg·kg -1 , total potassium content 9.87 g·kg -1 , available potassium content 179.45 mg·kg -1 .

[0052] Table 1 Fertilization patterns for different treatments

[0053]

[0054] 1.2 Measurement indicators and methods

[0055] 1.2.1 Determination of wheat population quantity:

[0056] After emergence, the basic seedlings were investigated; at the green-recovery stage, jointing stage, and filling stage, the total tiller numbers of wheat in each treatment were investigated.

[0057] 1.2.2 Determination of the photosynthetic characteristics of the flag leaves at the filling stage of wheat

[0058] At the filling stage, 10 flag leaves were selected from each plot, and the SPAD value and photosynthetic rate of the flag leaves were measured using a handheld SPAD detector and a portable photosynthesis meter, respectively, and the length and width were measured to calculate the leaf area.

[0059] Flag leaf area = leaf length * leaf width * 0.83

[0060] 1.2.3 Determination of wheat filling rate

[0061] Starting from 7 days after flowering, samples were taken every 7 days, 20 spikes were taken each time, the grains were shelled after being fully dried, the dry weight of the grains was measured, and the filling process of the grains was fitted using a trinomial to calculate various filling parameters.

[0062] Grain filling duration: Let f(x) = 3ax 2 + 2bx + c = 0, and the starting and ending times of filling X1 and X2 (X1 < X2) were obtained. Grain filling duration = X2 - X1.

[0063] Theoretical maximum grain weight: Substitute the grain filling ending time X2 into the grain weight growth equation to obtain the theoretical maximum grain weight = aX23 +bX2 2 +cX2 + d。

[0064] Average filling rate = Theoretical maximum grain weight / Grain filling duration

[0065] Maximum grain filling rate: Take the second derivative of f(x) and set the derivative to 0, obtaining X3 = -2b / 6a, which is the time when the maximum grain filling rate occurs. Substitute the time when the maximum grain filling rate occurs into the grain filling rate equation = 3aX3 2 +2bX3 + c to obtain the maximum filling rate.

[0066] Effective filling duration: Define the linear growth stage of the grain filling curve as the part where the slope of the curve ≥ 1. Let f'(x) = 3ax² + 2bx + c = 0.1, obtaining X4 and X5 (X4 < X5), and the effective filling duration = X4 - X5.

[0067] 1.2.4 Measurement of wheat yield

[0068] At harvest, enclose 1 m 2 of wheat and investigate the number of spikes per mu, the number of grains per spike, and the 1000-grain weight.

[0069] Theoretical wheat yield = Number of spikes per mu * Number of grains per spike * 1000 - grain weight * 0.85.

[0070] 1.2.5 Measurement of dry matter accumulation and translocation of wheat

[0071] Dry matter translocation amount before anthesis = Dry weight of vegetative organs at anthesis - Dry weight of vegetative organs at maturity

[0072] Dry matter translocation efficiency before anthesis = Dry matter translocation amount before anthesis / Dry weight of vegetative organs at anthesis

[0073] Contribution rate of dry matter translocation amount before anthesis to grain yield = Dry matter translocation amount before anthesis / Dry weight of grains at maturity

[0074] Dry matter production amount after anthesis = Dry weight of grains at maturity - Dry matter translocation amount before anthesis

[0075] Contribution rate of dry matter production amount after anthesis to grain yield = Dry matter production amount after anthesis / Dry weight of grains at maturity

[0076] 1.2.6 Measurement of nitrogen accumulation and translocation of wheat

[0077] Randomly select 30 wheat plants per plot at anthesis and maturity, separate them into vegetative organs and reproductive organs, dry, weigh, and pulverize them, and determine the total nitrogen by the Kjeldahl method.

[0078] Organ nitrogen accumulation amount = Organ dry matter amount * Organ total nitrogen amount

[0079] Pre-flowering nitrogen translocation amount = Nitrogen accumulation in vegetative organs during flowering period - Nitrogen accumulation in vegetative organs during maturity period. Pre-flowering nitrogen translocation efficiency = Pre-flowering nitrogen accumulation / Translocation amount / Nitrogen accumulation in vegetative organs during flowering period.

[0080] Contribution of pre-flowering nitrogen translocation to grain nitrogen levels = Pre-flowering nitrogen translocation amount / Grain nitrogen accumulation at maturity

[0081] Post-flowering nitrogen accumulation = Grain nitrogen accumulation at maturity - Pre-flowering nitrogen translocation

[0082] Contribution of post-flowering nitrogen accumulation to grain nitrogen = Post-flowering nitrogen accumulation / Grain nitrogen accumulation at maturity

[0083] 1.2.7 Determination of Nitrogen Fertilizer Use Efficiency in Wheat

[0084] Nitrogen fertilizer absorption and utilization rate = (total nitrogen uptake by the aboveground parts of plants treated with nitrogen - total nitrogen uptake by the aboveground parts of plants in the control group without nitrogen) / amount of nitrogen fertilizer applied.

[0085] Nitrogen fertilizer agronomic utilization rate = (yield of nitrogen treatment - yield of control treatment without nitrogen) / nitrogen fertilizer application rate.

[0086] Nitrogen fertilizer partial productivity = nitrogen application treatment yield / nitrogen fertilizer application rate.

[0087] Harvest index = grain yield / biomass yield.

[0088] 1.2.8 Determination of Soil Mineral Nitrogen

[0089] Soil samples were collected from the plot at three depths: 0-60 cm during the wheat overwintering, jointing, and maturity stages, with each layer being 20 cm thick. After collection, one portion of the soil samples was immediately dried to determine soil moisture content, while the other portion of fresh soil samples was brought back to the laboratory to determine the nitrate and ammonium nitrogen content. The determination procedure was as follows: 5.00 g of fresh soil sample was weighed, and 50 mL of 1 mol / L KCl solution was added. The mixture was shaken at 25℃ and 200 rpm for 1 h, then filtered. The extract was stored under cold storage or immediately determined using a SYSLYZER 3000 flow analyzer to determine the soil mineral nitrogen content.

[0090] 2. Test Results

[0091] 2.1 Effects of different treatments on wheat population size

[0092] The population dynamics of wheat at different growth stages were investigated. The results are shown in Table 2.

[0093] Table 2. Effects of different treatments on wheat population size

[0094]

[0095] Table 2 shows that there were no significant differences in wheat population size among the treatments during the emergence stage. However, significant differences emerged after the tillering stage. Before winter, the tillering per plant was M2>M6>M5>M4>M3>M1 in Cangmai 6002, and M2>M4>M6>M5>M3>M1 in Jiemai 19. The largest population size for both varieties occurred at the jointing stage in the M2 treatment, followed by the M3 treatment. The remaining treatments showed varying patterns among different varieties: M4>M5>M6>M1 in Jiemai 19, and M5>M4>M1>M6 in Cangmai 6002. After the jointing stage, the population size began to decline. During the grain-filling stage, the population size was M3>M5>M2>M4>M6>M1 in Jiemai 19, and M5>M3>M4>M2>M6>M1 in Cangmai 6002. The heading rate of the M2 treatment was significantly lower than that of other treatments by 10.83%-25.43% between the two varieties. This indicates that the increase in the number of tillers during the jointing stage due to a single application of fertilizer as basal fertilizer is mostly ineffective tillering, which is not conducive to yield formation. Layered fertilization is beneficial to building a reasonable number of tillers during the wheat growth period, promoting wheat heading, and laying the foundation for high and stable yield.

[0096] 2.2 Effects of different treatments on flag leaf area and chlorophyll content during wheat grain-filling stage

[0097] The effects of different treatments on the flag leaf area and chlorophyll content during the grain-filling stage of wheat were investigated. The results are shown in Table 3.

[0098] Table 3 Effects of different treatments on flag leaf area and chlorophyll content during wheat grain-filling stage

[0099]

[0100] As shown in Table 3, fertilization methods had a significant impact on the SPAD value and leaf area of ​​the flag leaf during the grain-filling stage of both wheat varieties. For Cangmai 6002 wheat, the SPAD value of the flag leaf during the grain-filling stage was: M3>M4>M5>M2>M6>M1, with significant differences between M3, M4, and M5 and M1, M2, and M6. For Jiemai 19 wheat, the SPAD value of the flag leaf during the grain-filling stage was: M3>M5>M6>M4>M2>M1, with significant differences between M3 and M2, and between M6, M5, M4, M3, M2, and M1. The flag leaf area of ​​Cangmai 6002 during the grain-filling stage was M3>M4>M5>M6>M2>M1, while that of Jiemai 19 was M3>M5>M4>M2>M6>M1. The maximum leaf area for both varieties was observed in the M3 treatment, with significant differences compared to the M1 and M2 treatments. Significant differences compared to the M4 treatment were only observed in Jiemai 19, while no significant differences were observed between the M4 and M5 treatments in either variety. Nitrogen, a mineral element crucial for plant growth, plays a vital role in leaf morphology and chlorophyll content. Compared to a single basal application of fertilizer, topdressing during the jointing stage and stratified fertilization can effectively increase the flag leaf area and chlorophyll content of wheat while maintaining a constant total nitrogen supply.

[0101] 2.3 Effects of different treatments on the photosynthetic rate of flag leaves during the grain-filling stage of wheat

[0102] The effects of different treatments on the photosynthetic rate of the flag leaf during the grain-filling stage of wheat were investigated. The results are shown in Table 4.

[0103] Table 4 Effects of different treatments on the photosynthetic rate of flag leaves during the grain-filling stage of wheat

[0104]

[0105] Table 4 shows that the photosynthetic rate of flag leaves in Cangmai 6002 14 days after flowering was: M3>M5>M4>M6>M1>M2; and 28 days after flowering, it was: M5>M4>M6>M3>M1>M2. For Jiemai 19, the photosynthetic rate of flag leaves 14 days after flowering was: M3>M5>M4>M6>M2>M1; and 28 days after flowering, it was: M5>M4>M3>M6>M2>M1. Nitrogen plays an important role in improving the photosynthetic rate of plant leaves. The experimental results show that compared to a single basal application of fertilizer, topdressing at the jointing stage and deep application of nitrogen fertilizer mixed with inhibitors can significantly improve the photosynthetic rate of flag leaves in the early grain-filling stage of wheat; while deep application of nitrogen fertilizer and deep application of nitrogen fertilizer mixed with inhibitors in the late grain-filling stage can effectively delay the senescence of functional leaves and improve the grain-filling rate.

[0106] 2.4 Effects of different treatments on wheat grain-filling characteristics

[0107] Dynamic changes in grain dry weight accumulation of different wheat varieties under different treatments, as follows: Figure 1 As shown.

[0108] Figure 1 The results showed that the dynamic changes in grain dry weight accumulation of different wheat varieties under different treatments all exhibited an "S"-shaped curve, which included three stages: a gradual increase period, a rapid increase period, and a slow increase period. Specifically, the grain filling rate increased slowly from 7 to 14 days after flowering; the grain filling rate increased rapidly from 14 to 21 days after flowering and reached its maximum value during this period; and the grain filling rate decreased rapidly from 28 to 35 days after flowering, and then entered the slow increase period again.

[0109] The wheat grain-filling process for each treatment was fitted using a trinomial equation, and the characteristic parameters of each grain-filling process were calculated based on this, as shown in Table 5.

[0110] Table 5 Effects of different treatments on wheat grain-filling parameters

[0111]

[0112] Table 5 shows that fertilization treatments prolonged the grain-filling duration and effective grain-filling duration of wheat, and increased the maximum grain-filling rate and theoretical maximum thousand-grain weight.

[0113] Figure 1 As shown in Table 5, under the same nitrogen application level, compared with single-layer basal application of nitrogen fertilizer and topdressing during the greening period, layered application of nitrogen fertilizer effectively prolonged the wheat grain-filling period and increased the theoretical maximum thousand-grain weight.

[0114] 2.5 Effects of different treatments on wheat yield

[0115] The effects of different treatments on wheat yield and its components were investigated. The results are shown in Table 6.

[0116] Table 6 Effects of different treatments on wheat yield and its components

[0117]

[0118] Table 6 shows that each treatment had varying degrees of impact on the yield and yield components of different drought-resistant wheat varieties. For Cangmai 6002, the grain number per spike was M5>M4>M2>M3>M6>M1, with significant differences between treatments M5 and M4 and treatments M1, M3, and M6. For Jiemai 19, the grain number per spike was M3>M4>M5>M6>M2>M1, with significant differences between treatment M3 and treatments M1, M2, and M6. Compared to no fertilization and single shallow fertilization, layered fertilization with inhibitors and topdressing during the greening stage significantly increased the number of spikes per acre. The maximum number of spikes per acre for both varieties occurred in treatments M3 (Cangmai 6002) and M5 (Jiemai 19), respectively. Furthermore, there were no significant differences in the number of spikes per acre between these two treatments for both varieties, and both treatments significantly increased the number of spikes per acre compared to treatments M1 and M2. The maximum thousand-grain weight of Cangmai 6002 was 38.72 g in treatment M4, while the maximum thousand-grain weight of Jiemai 19 was 40.55 g in treatment M3. The maximum yield of Cangmai 6002 was 391.04 kg / mu in treatment M5, representing a significant increase of 28.93%, 8.37%, and 12.03% compared to treatments M1, M2, and M6, respectively. However, the yield difference with treatments M3 and M4 was not significant. Similarly, the maximum yield of Jiemai 19 was 381.53 kg / mu in treatment M3, representing a significant increase of 30.51%, 19.91%, 10.84%, and 22.63% compared to treatments M1, M2, M4, and M6, respectively. The yield difference with treatment M5 was not significant, but the yield differences between treatment M5 and treatments M1, M2, and M6 were also significant. This indicates that compared to a single-layer basal application of nitrogen fertilizer, topdressing during the greening period, deep application of nitrogen fertilizer, and deep application of nitrogen fertilizer mixed with inhibitors can all effectively increase wheat yield. Among them, deep application of nitrogen fertilizer mixed with inhibitors and topdressing during the greening period have a better yield-increasing effect than deep application of nitrogen fertilizer, while deep application of urea-formaldehyde has no significant effect on yield increase.

[0119] 2.6 Effects of different treatments on wheat dry matter accumulation and translocation

[0120] Dry matter translocation of two types of wheat under different treatments and their contribution to grain yield are as follows: Figure 2 As shown.

[0121] Figure 2The results showed that in Cangmai 6002, the pre-flowering dry matter translocation of each treatment was M3>M5>M4>M2>M6>M1, with treatments M3 and M5 showing significant increases of 11.90% and 7.81% compared to M2, respectively. In Jiemai 19, the pre-flowering dry matter translocation of each treatment was M5>M4>M3>M6>M2>M1, with treatment M5 showing a significant increase of 10.16% compared to M2. The contribution rates of pre-flowering dry matter to grain production for the two varieties were 19.47%-21.66% (Cangmai 6002) and 17.97%-20.80% (Jiemai 19), respectively. In Cangmai 6002, the post-flowering dry matter translocation of each treatment showed the order M3>M5>M4>M2>M6>M1, with treatments M5, M4, and M3 showing a significant increase of 8.19%-18.92% compared to M2. In Jiemai 19, the post-flowering dry matter translocation of each treatment also showed the order M3>M5>M4>M6>M2>M1, with treatments M5, M4, and M3 showing a significant increase of 8.99%-17.90% compared to M2. The contribution rate of post-flowering dry matter production to grain yield for the two varieties was 78.34%-80.52% (Cangmai 6002) and 79.19%-81.26% (Jiemai 19), respectively. This indicates that topdressing during the greening stage, deep application of nitrogen fertilizer, and deep application of nitrogen fertilizer mixed with inhibitors can all effectively increase the post-flowering dry matter accumulation in wheat.

[0122] 2.7 Effects of different treatments on nitrogen accumulation and translocation in wheat

[0123] The effects of different treatments on nitrogen accumulation and translocation in wheat are as follows: Figure 3 As shown.

[0124] Figure 3 The results showed that nitrogen accumulation in wheat mainly originated before flowering, with pre-flowering nitrogen accumulation accounting for 77%–90% of total nitrogen accumulation. The changes in pre- and post-flowering nitrogen accumulation and grain nitrogen accumulation were generally consistent between the two treatments, showing the order M5 > M3 > M4 > M2 > M6 > M1. In Jiemai 19, the grain nitrogen accumulation in the M4 treatment was significantly increased by 7.08% compared to M2. In Cangmai 6002, the post-flowering nitrogen accumulation and post-flowering nitrogen translocation in the M4 treatment were significantly increased by 8.50% and 39.68% respectively compared to M2. This suggests that compared to a single-shot nitrogen application at sowing, the higher grain nitrogen accumulation from stratified nitrogen application likely originates from post-flowering nitrogen accumulation and translocation. Compared to the M4 treatment, the M3 treatment showed increased nitrogen accumulation before and after flowering, increased nitrogen translocation after flowering, and increased grain nitrogen accumulation, with significant differences observed in 6002. In contrast, compared to the M5 treatment, all of these indicators decreased, with significant differences observed in Jiemai 19. Furthermore, compared to M5, M3 and M4 showed a higher contribution rate of nitrogen translocation to grain production, while M3 and M4 showed a lower contribution rate. This indicates that deep application of nitrogen fertilizer is more beneficial for increasing nitrogen accumulation in vegetative organs after flowering, rather than in grain production, compared to topdressing during the greening stage.

[0125] 2.8 Effects of different treatments on nitrogen fertilizer use efficiency in wheat

[0126] The effects of different treatments on nitrogen fertilizer use efficiency in wheat were investigated. The results are shown in Table 7.

[0127] Table 7 Effects of different treatments on nitrogen fertilizer use efficiency in wheat

[0128]

[0129] As shown in Table 7, the nitrogen fertilizer absorption and utilization rate of both wheat varieties was M5>M3>M4>M2>M6. In Jiemai 19, the nitrogen fertilizer absorption and utilization rate of the M5 treatment was significantly higher than that of the other treatments, while in Cangmai 6002, there was no significant difference with the M3 treatment. In both varieties, the nitrogen fertilizer absorption and utilization rate of the M3 treatment was significantly higher than that of M2 and M4. The fertilizer absorption and utilization rate of the M4 treatment was only significantly different from that of M2 in Cangmai 6002. For Cangmai 6002, the nitrogen fertilizer agronomical utilization rate and nitrogen fertilizer partial productivity were both M5>M3>M4>M2>M6, with the M5 treatment showing a significant increase in nitrogen fertilizer agronomical utilization rate of 8.43% compared to the M2 treatment. For Jiemai 19, the nitrogen fertilizer agronomical utilization rate and nitrogen fertilizer partial productivity were M3>M5>M4>M2>M6, with the M3 and M5 treatments showing significant increases in nitrogen fertilizer agronomical utilization rate of 19.79% and 15.69% respectively compared to the M2 treatment, and the M3 treatment showing a significant increase in nitrogen fertilizer agronomical utilization rate of 10.72% compared to the M4 treatment.

[0130] The harvest index among treatments of Cangmai 6002 was M5>M4>M6>M3>M2>M1, and the harvest index among treatments of Jiemai 19 was M5>M4>M3>M2>M6>M1. The differences in M5, M3, M4, M2 and M1 among treatments within both varieties were significant, indicating that fertilization treatment is beneficial to increasing the harvest index of wheat. In Cangmai 6002, the harvest index of treatments M4 and M5 increased significantly by 8.47% and 13.59% compared with M2, respectively. In Jiemai 19, the harvest index of treatments M4 and M5 increased significantly by 1.43% and 5.07% compared with M2, respectively. This indicates that compared with the "one-shot" nitrogen application at sowing, deep application of nitrogen fertilizer and deep application of nitrogen fertilizer mixed with inhibitors can effectively promote the transport of wheat photosynthetic assimilates to grains and improve the wheat harvest index. The harvest index of treatment M5 was significantly higher than that of treatment M3 in Cangmai 6002 by 9.92%, but the difference in Jiemai 19 was not significant.

[0131] 2.7 Effects of different treatments on soil mineral nitrogen

[0132] Soil mineral nitrogen content in 0-60cm depth for each treatment is as follows: Figures 4-5 As shown.

[0133] Overall, soil mineralized calcium content decreased with the advancement of wheat growth and the increase of vertical depth. Before winter, the mineralized nitrogen content in the 0-20cm soil layer was M2>M3>M4>M5>M1, with the M2 treatment showing a significant increase of 11.37%-22.89% compared to other treatments, while the differences among the other treatments were not significant. At the jointing stage, the mineralized nitrogen content in the 0-20cm soil layer was M3>M4>M2>M5>M1, with the M3 treatment showing a significant increase of 11%-32% compared to other treatments, and the M4 treatment showing a significant increase of 13%-17% compared to M1, M2, and M5. At maturity, there were no significant differences in the mineralized nitrogen content in the 0-20cm soil layer among the treatments. During the wheat growing season, the variation in mineralized nitrogen content in the 0-20cm soil layer was M2>M3>M4>M1>M5. Before overwintering, the mineral nitrogen content in the 20-40cm soil layer showed the order M4>M2>M5>M3>M1. At the jointing stage, the order was M3>M4>M5>M2>M1. At maturity, the order was M5>M4>M3>M2>M1. The M5 treatment showed a significant increase in mineral nitrogen content compared to the M1 and M2 treatments, by 14.83 and 28.10, respectively. Before overwintering, the mineral nitrogen content in the 40-60cm soil layer showed the order M4>M2>M5>M3>M1. At the jointing stage, the order was M3>M5>M4>M2>M1. At maturity, the order was M5>M2>M4>M3>M1. Overall, the decrease coefficient of mineral nitrogen in each soil layer (0-60cm) tended to be stable during the wheat growth period, indicating that the distribution of mineral nitrogen in each soil layer under natural conditions was mainly affected by leaching. Layered fertilization and topdressing during the greening stage significantly increased the mineral nitrogen content in the soil layer adjacent to the fertilizer application during the growing season. At this time, the distribution of soil mineral nitrogen was mainly affected by fertilizer hydrolysis and nitrification. During the wheat growth period, the mineral nitrogen content in the 20-60cm soil layer of the M5 treatment was relatively stable and significantly higher than other treatments at the maturity stage, indicating that deep application of inhibitors prolonged the fertilizer release cycle, ensuring sufficient nitrogen supply during the wheat growth period and laying the foundation for increased yield.

[0134] Correlation analysis showed that the mineral nitrogen content in the 20-40cm soil layer during the jointing stage was significantly correlated with the number of wheat ears per mu (unit of land area). The mineral nitrogen content in the 20-60cm soil layer during the jointing stage significantly affected the pre-flowering nitrogen accumulation and translocation of wheat, thus affecting wheat yield. The mineral nitrogen content in the 0-60cm soil layer during the maturity stage significantly affected the yield components, yield, and grain nitrogen accumulation of wheat. The mineral nitrogen content in the 20-40cm soil layer during the maturity stage was significantly positively correlated with the post-flowering nitrogen accumulation. Therefore, sufficient nutrient supply is beneficial to wheat yield formation.

[0135] Example 2

[0136] This experiment aims to use Cangmai 6002 as the test subject to investigate the effects of different fertilizer stratification patterns on the yield and water and fertilizer use efficiency of dryland wheat fields under the application levels of 13.4 kg nitrogen, 9.2 kg phosphorus, and 2.8 kg potassium per mu. The goal is to optimize the fertilization method of dryland winter wheat within the framework of a simplified wheat production model, thereby improving wheat yield and resource utilization efficiency.

[0137] 1. Materials and Methods

[0138] 1.1 Experimental Design

[0139] The experiment included three stratified fertilization treatments (as shown in Table 8), with three replicates and a plot area of ​​12m². 2 (3m×4m) Randomized block arrangement, wide-row furrow sowing, furrows 7cm wide and 12cm deep, with ridges 20cm wide along the sides. Seeds are evenly sown in the furrows and covered with 2cm of soil. Sowing density is 17.5kg / mu. Conventional field management. Pre-sowing soil properties: pH 7.86, organic matter content 8.60g·kg⁻¹. -1 Total salt content: 0.20%; Total nitrogen content: 0.14 g·kg⁻¹ -1 The alkaline nitrogen content is 74.26 mg·kg⁻¹. -1 Total phosphorus content: 0.25 g·kg -1 Available phosphorus content: 1920.97 mg·kg -1 Total potassium content: 9.87 g·kg -1 Available potassium content: 179.45 mg / kg -1 The experimental wheat-specific compound fertilizer was purchased from Huanghua Bofeng Agricultural Technology Service Co., Ltd., and the polyurethane-coated urea (containing nitrification inhibitors, with a final concentration of 1% nitrogen content) was produced by Shandong Nuoan Ecological Fertilizer Co., Ltd. on behalf of the Dryland Water-Saving Institute of Cangzhou Academy of Agricultural and Forestry Sciences.

[0140] Table 8 Fertilization patterns for different treatments

[0141]

[0142] 1.2 Measurement Indicators and Methods

[0143] 1.2.1 Measurement of photosynthetic characteristics of flag leaves during wheat grain-filling stage

[0144] During the grouting period, 10 flag leaves were selected from each plot. The SPAD value and photosynthetic rate of the flag leaves were measured using a handheld SPAD meter and a portable photosynthesis meter, and the length and width were measured to calculate the leaf area.

[0145] 1.2.2 Determination of wheat yield

[0146] Harvesting time: 1m 2For wheat, investigate the number of ears per mu, the number of grains per ear, and the weight of 1,000 grains.

[0147] 1.2.3 Determination of available nitrogen in soil

[0148] Soil samples (0-40cm) were collected from the plot during the wheat jointing, flowering, and grain-filling stages, and the available nitrogen content in the soil was determined by alkaline hydrolysis distillation.

[0149] 1.2.4 Water and fertilizer utilization efficiency

[0150] Nitrogen fertilizer use efficiency: NUE = grain yield / nitrogen application rate

[0151] Water use efficiency: WUE = yield / water consumption during the growing season

[0152] 2. Test Results

[0153] 2.1 The effects of different treatments on the physiological characteristics and photosynthetic performance of flag leaves are shown in Table 9.

[0154] Table 9 Effects of different treatments on flag leaf physiological characteristics and photosynthetic performance

[0155]

[0156] Table 9 shows that the flag leaf area of ​​the M3 treatment during the grain-filling stage was the largest at 33.77 cm, significantly higher than that of the M1 treatment by 18.23%, indicating that 30 cm deep fertilization can support a larger canopy photosynthetic area. The SPAD value of the M3 treatment during the grain-filling stage reached 49.15, significantly higher than other treatments by 7.64%–23.02%; the differences between the M2 and M4 treatments and the M1 treatment were also significant, indicating that deep fertilization can delay leaf senescence. The photosynthetic rate was positively correlated with the SPAD value, with the M3 treatment showing a photosynthetic rate of 29.44 μmol / (m²) during the grain-filling stage. 2 ·s), which is 24.64% higher than M1.

[0157] 2.2 The effects of different treatments on the distribution of available nitrogen in the soil are shown in Table 10.

[0158] Table 10 Effects of different treatments on the distribution of available nitrogen in soil

[0159]

[0160] Table 10 shows that there was no significant difference in available nitrogen content in the 0-40 cm soil layer among the treatments at the jointing stage; at the flowering stage, the available nitrogen content in the 0-40 cm soil layer was M3 > M2 > M4 > M1, and at the grain-filling stage, it was M3 > M4 > M2 > M1. The available nitrogen content in the 0-40 cm soil layer at the flowering and grain-filling stages of treatment M3 was 72.34 mg / kg and 66.84 mg / kg, respectively, which were significantly higher than those of treatment M1 by 10.73% and 27.55%. This indicates that applying nitrogen fertilizer in a 30 cm stratified depth can optimize the vertical distribution of nitrogen, prolong the nitrogen supply capacity in the later stages of wheat growth, and reduce nitrogen loss from the surface layer.

[0161] 2.3 The effects of different treatments on wheat yield are shown in Table 11.

[0162] Table 11 Effects of different treatments on wheat yield

[0163]

[0164] As shown in Table 11, the yield of each treatment was M3 > M2 > M4 > M1. Among them, the M3 treatment had the highest yield of 371.93 kg / mu, which was significantly higher than the M1 and M4 treatments by 27.98% and 8.28%, respectively. The yield increase was mainly due to the synergistic increase in the number of ears per mu and the number of grains per ear. The M2 and M4 treatments also had significant yield increases of 21.57% and 18.19%, respectively, compared with the M1 treatment. This indicates that the stratified deep application of nitrogen fertilizer can optimize the nutrient supply during ear differentiation and grain filling, thereby increasing wheat yield.

[0165] 2.4 The effects of different treatments on wheat water and fertilizer use efficiency are shown in Table 12.

[0166] Table 12 Effects of different treatments on water and fertilizer use efficiency in wheat

[0167]

[0168] Table 12 shows that the nitrogen fertilizer use efficiency and water use efficiency of each treatment are in the order M3 > M2 > M4 > M1. Among them, the nitrogen fertilizer use efficiency of treatment M3 is 27.47 kg / kg, which is significantly higher than that of treatment M1 by 27.98%; the water use efficiency is 13.04 ± 0.93 kg / (hm²). 2 The nitrogen fertilizer application rate (*mm) was significantly higher than that of the M1 treatment by 22.09%, indicating that stratified deep application of nitrogen fertilizer can improve the efficiency of wheat resource utilization.

[0169] In summary, layered deep application of nitrogen fertilizer can effectively prolong nitrogen supply in the later stages of growth, increase the SPAD value and photosynthetic rate of flag leaves during the grain-filling period of wheat, promote the increase of the number of ears per mu and the number of grains per ear, thereby significantly increasing yield and improving water and fertilizer use efficiency. However, if the deep application depth is too deep (35cm), it will lead to increased root absorption resistance, which is not conducive to the formation of wheat yield. Therefore, the depth of layered deep application of nitrogen fertilizer for wheat should be 30cm.

[0170] Example 3

[0171] This experiment aims to verify the effect of furrowing and ridge setting on soil salinity. Sowing furrows 12cm wide and 7-10cm deep were set up, forming ridges 20cm wide between the furrows. Cangmai 6002 was conventionally sown using equal row spacing, with a row spacing of 16cm. The furrows and ridges can be set manually or using agricultural machinery (including the machinery described in Example 4 below).

[0172] The impact of furrowing and ridge planting on soil salinity is as follows: Figure 6 As shown, the impact of furrowing and ridge planting on soil moisture is as follows: Figure 7 As shown in the field planting effect diagram, Figure 8 As shown.

[0173] Figure 6 The results show that furrow sowing significantly reduced the soil salinity in the 0-5cm layer compared to conventional flat sowing, by 22.47%, demonstrating a good salt-avoidance effect. Furrow sowing and ridging create micro-topography, causing salt to move and accumulate towards the ridges. Throughout the wheat's growth period, the soil salinity in the 0-5cm layer was highest on the ridges, followed by the bottom of the furrows. Furrow-sown wheat showed a 15.22%-28.81% reduction in 0-5cm soil salinity compared to conventional sowing, indicating a significant natural salt-moving effect. Through salt avoidance and salt-moving mechanisms, furrow sowing significantly reduced the topsoil salinity during the growth period of drought-resistant, alkaline wheat, alleviating the stress of salt on wheat growth.

[0174] Figure 7 The results showed that when seeds were sown in furrows after removing the top layer of dry soil, the soil moisture content in the 0-10cm layer was significantly higher than that of conventional sowing by 13.32% during the seedling stage, which was beneficial to seed germination. Throughout the entire growth period, the soil moisture content in the 0-10cm layer was 7.48%-15.01% higher than that of conventional sowing. After snowfall from early January to mid-February, the soil moisture content in the 0-10cm layer was significantly higher than that of conventional sowing by 10.41%-15.01%, indicating a significant effect of rain and snow accumulation in the furrows.

[0175] In summary, the furrow sowing method described in this embodiment can effectively prevent salt accumulation, collect rainwater, and increase soil moisture content.

[0176] Example 4

[0177] In response to the layered nitrogen application method for drought-resistant and alkaline wheat in this invention, the inventors have also developed a brand-new agricultural machine capable of layered fertilization, namely the semi-no-till layered fertilization and seeding machine for drought-resistant and alkaline wheat in this embodiment.

[0178] 1. The specific structure of the drought-resistant, alkali-tolerant wheat semi-no-till stratified fertilization seeder is as follows:

[0179] The semi-no-till stratified fertilization and seeding machine for drought-resistant and alkaline wheat includes a rear frame, which is welded from square tubular profiles. A first fertilizer box, a second fertilizer box, and a seed box are installed on the top of the rear frame. The bottoms of the first fertilizer box, the second fertilizer box, and the seed box are all fixed to the rear frame via a box frame. A fertilizer metering device is installed at the bottom of the first fertilizer box and the second fertilizer box, and a seed metering device is installed at the bottom of the seed box.

[0180] A soil-crushing device is installed below the front end of the rear frame. Behind the soil-crushing device are a shallow fertilization device and a seeding device. The shallow fertilization device is connected to the fertilizer dispenser at the bottom of the first fertilizer box through the first fertilizer delivery pipe. The seeding device is connected to the seed dispenser at the bottom of the seed box through the seed delivery pipe. A pressing roller is installed below the rear end of the rear frame.

[0181] A detachable front frame is provided at the front end of the rear frame. A deep fertilization device is provided below the front frame. The deep fertilization device is connected to the fertilizer discharge device at the bottom of the second fertilizer box through a second fertilizer delivery pipe. A traction mechanical connection and a three-point suspension structure are fixed at the top of the front frame.

[0182] Both the fertilizer metering device and the seed metering device are grooved wheel structures. These devices achieve seed and fertilizer dispensing through the rotation of an internal grooved wheel. The working principle is as follows: a transmission device drives the seed (fertilizer) dispensing shaft to rotate, and the grooved wheel rotates within the seed (fertilizer) box. When the grooved wheel groove enters the seed layer (fertilizer granules), the seeds (fertilizer granules) fill the groove. As the groove rotates to the seed dispensing port, the seeds (fertilizer granules) detach from the groove due to gravity or centrifugal force and are discharged through the seed guide tube. Grooved wheel seed and fertilizer metering devices are commonly used components in agricultural seeding machinery; their specific structure will not be elaborated here.

[0183] The press roller is connected to the rear frame via a roller frame, which is typically hinged to the rear frame. A support rod is positioned above the roller frame; its lower end is hinged to the roller frame, and its upper end is slidably connected to the rear frame. A spring is usually fitted onto the support rod, providing downward pressure when the press roller contacts the ground. The design of the roller frame, support rod, and spring is existing technology in agricultural machinery, and the press roller at the rear of a seeder typically uses this mounting structure. The press roller provides power to the fertilizer applicator and seed applicator through a transmission system, which is a chain drive system. A sprocket A is installed at the shaft end of the press roller, and four sprockets B are installed at the hinge of the roller frame (the four sprockets are installed on the same shaft). The fertilizer applicator and seed applicator are also equipped with a sprocket. The sprocket A at the shaft end of the press roller transmits power to one of the sprockets B at the roller frame through a chain. The sprocket B then transmits power to the other three sprockets B through a sprocket shaft. The other three sprockets B transmit power to the fertilizer applicator and seed applicator respectively through chains, thereby enabling the fertilizer applicator and seed applicator to work.

[0184] The soil-breaking device includes a soil retaining cover, which is fixed to the bottom of the rear frame. A cutter shaft is located below the soil retaining cover and is rotatably connected to the side plates on both sides of the soil retaining cover. Several rotary tillage blades are mounted on the cutter shaft. A gearbox is located on top of the soil retaining cover, and the power output end of the gearbox is connected to the cutter shaft. The gearbox has two power output ends. The cutter shaft is divided into two sections, arranged on both sides of the power output ends of the gearbox, and is fixedly connected to the power output ends of the gearbox. A power output end is located at the front of the gearbox, which can be connected to the traction power machinery at the front via a universal joint coupling; the traction power machinery is typically a tractor.

[0185] The shallow fertilization device includes several shallow trenching shovels arranged in a row along the transverse side of the rear frame, with adjacent shovels spaced apart. The upper ends of the shallow trenching shovels are fixed to the rear frame, and a first row of fertilizer pipes is fixed to the rear of the shovels, connecting to a first fertilizer delivery pipe. Mounting sleeves are welded to the rear frame. The legs of the shallow trenching shovels are inserted into the mounting sleeves from below and secured by tightening bolts connected to the mounting sleeves.

[0186] The sowing device includes several seed-discharging nozzles, which are located behind the shallow furrow shovel and correspond one-to-one with it. The seed-discharging nozzles are duckbill-shaped with their openings facing rearward. The upper end of each nozzle is welded to an inoculation tube, which is fixed to the rear frame and connected to a seed delivery tube. In this embodiment, a mounting sleeve is also welded to the rear frame. After the inoculation tube is inserted into the mounting sleeve from below, it is fixed by a tightening bolt connected to the mounting sleeve.

[0187] The deep fertilization device includes several deep trenching shovels. The upper end of each shovel is fixed to the front frame, and a second row of fertilizer pipes is fixed to the rear of each shovel, connecting to a second fertilizer delivery pipe. Sleeves are fitted onto the legs of the deep trenching shovels, and these sleeves are connected to the front frame via U-bolts. Two adjusting bolts are threaded onto the sleeves, and these adjusting bolts rest against the legs of the deep trenching shovels.

[0188] A total of five deep trenching shovels are installed, and the five deep trenching shovels are fixed on the front frame in a two-in-the-front and three-in-the-back arrangement, which can avoid snagging on straw and weeds to a certain extent.

[0189] It should be noted that the first fertilizer delivery pipe, the second fertilizer delivery pipe, and the seed delivery pipe are all plastic flexible tubes, specifically corrugated pipes.

[0190] The front end of the rear frame is equipped with a rear three-point suspension structure, and the rear end of the front frame is welded with two connecting ears. The two connecting ears can be connected to the two lower suspension points of the rear three-point suspension structure through pins. The front frame can be detached and connected to the rear three-point suspension structure through the connecting ears.

[0191] A suspension link is installed above the front frame, and the two ends of the suspension link are connected to the upper suspension points of the front three-point suspension structure and the rear three-point suspension structure, respectively.

[0192] 2. The working process of the semi-no-till stratified fertilization seeder for drought-resistant and saline-alkali wheat is as follows:

[0193] The layered fertilization seeder is suspended at the rear of the traction machine. The soil-crushing device pulverizes the soil for no-till seeding. The deep furrow shovel at the front performs deep fertilization, while the shallow furrow shovel at the rear performs shallow fertilization. Deep fertilization meets the nutritional needs of the deep root system of wheat. It should be noted that the shallow furrow shovel is positioned 5-7 cm lower than the seed nozzle to prevent the seeds from being too close to the fertilizer after sowing, which could burn the seedlings. In this embodiment, the shallow fertilization device and the seeding device are located on the outer side of the rotary tiller's rotation circumference. The entire blade shaft is covered with rotary tillers, implementing a comprehensive rotary tillage and soil-crushing method.

[0194] In summary, the novel seeder in this embodiment adopts a layered fertilization method, with shallow and deep fertilization layers that can meet the nutrient requirements of drought-resistant wheat throughout its entire growth cycle, improve the absorption of fertilizer by the deep roots of wheat, and ensure the yield of drought-resistant wheat.

[0195] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for stratified nitrogen application to drought-resistant and alkaline wheat, characterized in that, The stratification is divided into two layers. The first layer adopts the conventional base fertilizer application method, with the fertilizer amount being 55-60% of the total nitrogen fertilizer and the depth being 8-10cm. The second layer adopts the slow-release fertilizer application method, with the fertilizer amount being 40-45% of the total nitrogen fertilizer and the depth being 25-35cm.

2. The method for stratified nitrogen application to drought-resistant and alkaline wheat according to claim 1, characterized in that, The method also includes the combined application of phosphate and potash fertilizers.

3. The method for stratified nitrogen application to drought-resistant and alkaline wheat according to claim 2, characterized in that, The total application rate of nitrogen, phosphorus and potassium in the method is: 13.4 kg of nitrogen, 9.2 kg of phosphorus and 2.8 kg of potassium per mu.

4. The method for stratified nitrogen application to drought-resistant and alkaline wheat according to claim 3, characterized in that, The phosphorus and potassium fertilizers were applied to the first layer using conventional basal fertilizer application methods.

5. The method for stratified nitrogen application to drought-resistant and alkaline wheat according to claim 4, characterized in that, The slow-release fertilization method includes coated urea, which contains inhibitors.

6. The method for stratified nitrogen application to drought-resistant and alkaline wheat according to claim 5, characterized in that, The inhibitors include nitration inhibitors.

7. The method for stratified nitrogen application to drought-resistant and alkaline wheat according to claim 6, characterized in that, The final concentration of the nitration inhibitor is 1% of the nitrogen content.

8. The method for stratified nitrogen application to drought-resistant and alkaline wheat according to claim 7, characterized in that, The method also includes the use of furrow-ridge tillage technology; the furrow refers to a sowing furrow, 12cm wide and 7-10cm deep; the ridge refers to a ridge 20cm wide formed between the furrows.

9. The application of the drought-resistant and alkaline wheat stratified nitrogen application method according to any one of claims 1-8 in wheat cultivation.

10. The application according to claim 9, characterized in that, The application allows wheat cultivation to be done without topdressing, which saves costs and solves the problem of difficulty in topdressing in spring when there is no water. It can also loosen the soil, improve the soil structure of saline-alkali land, and the furrows and ridges can also prevent salt from entering the soil.

Images