Method for improving cotton yield and nitrogen fertilizer utilization rate and application

Abstract

The invention provides a method for improving cotton yield and nitrogen fertilizer utilization rate. Belongs to the technical field of crop planting. According to the method, the nitrogen fertilizer is uniformly mixed with a certain proportion of DCD and N-butyl thiophosphoric triamide (NBP T) for combined application, meanwhile, the fertilization process is optimized and improved, the yield of cotton can be remarkably increased, and the apparent recovery rate and the agricultural utilization rate of the nitrogen fertilizer of the cotton can be increased. The invention further provides application of the method in cotton seeds, and technical support is provided for nitrogen reduction and efficiency improvement in cotton field production.

Description

Technical Field

[0001] The invention relates to the technical field of crop planting, and more specifically to a method and application for improving cotton yield and nitrogen fertilizer utilization rate. Background Art

[0002] Cotton is an important cash crop in my country, as well as an important fiber and oil crop. In recent years, cotton has played an important role in the development of my country's agricultural economy, and its output ranks second in the world. However, there is a large gap between the supply and demand of cotton in my country. The labor cost of cotton planting has increased, and the input cost of production materials has increased. Therefore, how to scientifically and effectively increase cotton production while maintaining my country's existing cotton advantages and making the economic benefits of cotton reach new heights is a hot topic for future research.

[0003] Fertilization is an indispensable part of my country's construction of modern agriculture. Relevant studies have shown that fertilizers contribute an average of about 45% to the final formation of crop yields. In particular, they are affected by the three elements of nitrogen, phosphorus and potassium, and play an irreplaceable role in the entire growth process of crops. Among them, nitrogen is the most critical factor in increasing crop yields. Nitrogen fertilizer application plays an important role in the stable and high yield of crops. Studies have shown that when cotton achieves high yields, the nitrogen supply is relatively sufficient throughout the growth process; conversely, nitrogen deficiency will affect the reproductive growth and nutritional growth of cotton in the middle and late stages, leading to a decrease in yield. At present, my country's main cotton producing areas are in Xinjiang. In 2022, Xinjiang's cotton production will be 5.394 million tons, accounting for about 90.2% of the country's total cotton production. However, in reality, farmers generally apply excessive nitrogen fertilizers to ensure stable and high yields of cotton, resulting in problems such as nitrogen fertilizer waste and low nitrogen fertilizer utilization.

[0004] A large number of studies have shown that the application of nitrogen fertilizers with nitrogen inhibitors can promote crop nitrogen absorption, improve nitrogen fertilizer utilization, reduce nitrogen fertilizer losses, and reduce nitrogen fertilizer ammonia volatilization. Nitrogen inhibitors are mainly divided into urease inhibitors and nitrification inhibitors. Urease inhibitors mainly inhibit the activity of soil urease (urea amide hydrolase), thereby regulating the hydrolysis reaction rate of urea and prolonging the retention time of amide nitrogen to facilitate crop absorption and utilization of nitrogen. Nitrification inhibitors mainly slow down the conversion rate of ammonium nitrogen to nitrate nitrogen by inhibiting the activity of nitrifying bacteria in the soil and blocking the reaction enzymes in the nitrification process.

[0005] Dicyandiamide (DCD) is a white powdery crystal with good safety, strong water solubility, and is not easily degraded by aquatic organisms. In 2000, the U.S. Plant Food Administration (AAPECO) officially identified DCD as a nitrification inhibitor. Prior to this, DCD was usually directly used as a nitrogen fertilizer due to its excellent properties and high nitrogen content. N-butylthiophosphoric acid triamide (NBPT) is a white crystal or white powder with good urease inhibition effect. It is the most widely used and successful urease inhibitor in agricultural production. NBPT can effectively control ammonia volatilization, and DCD can significantly reduce N2O emissions, which has an improvement effect on mitigating the greenhouse effect. However, there is little research on the synergistic effect of the two in the existing technology, and the current yield increase effect is not satisfactory.

[0006] Therefore, how to provide an efficient and reasonable cotton fertilization plan to increase cotton yield, improve nitrogen utilization rate, and achieve the purpose of reducing nitrogen fertilizer application and increasing efficiency is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0007] In view of this, the present invention provides a method for improving cotton yield and nitrogen fertilizer utilization rate. By mixing nitrogen fertilizer with dicyandiamide and N-butylthiophosphoric acid triamide in a specific ratio and applying them, the nitrogen utilization rate of cotton can be significantly improved, thereby achieving the effect of reducing nitrogen fertilizer application and increasing efficiency, and improving cotton yield.

[0008] In order to achieve the above object, the present invention adopts the following technical solution:

[0009] A method for improving cotton yield and nitrogen fertilizer utilization rate comprises applying 1.5% to 3% of dicyandiamide and 1% to 2% of N-butylthiophosphoric acid triamide based on the total weight of pure nitrogen contained in the nitrogen fertilizer while applying nitrogen fertilizer.

[0010] Preferably, when applying nitrogen fertilizer, 1.5% to 3% of dicyandiamide and 2% of N-butylthiophosphoric acid triamide are applied based on the total weight of pure nitrogen contained in the nitrogen fertilizer.

[0011] Preferably, the nitrogen fertilizer is applied twice in equal amounts as a base fertilizer and a topdressing during the initial flowering period, or the base fertilizer and multiple topdressings are applied in a certain ratio.

[0012] Further preferably, the nitrogen fertilizer is urea.

[0013] Preferably, a certain amount of phosphorus fertilizer and potassium fertilizer is applied together with nitrogen fertilizer as base fertilizer.

[0014] Further preferably, the phosphate fertilizer is triple superphosphate, wherein the P2O5 content is ≥42%; and the potash fertilizer is potassium sulfate, wherein the K2O content is ≥51%.

[0015] Preferably, every 667m 2 Based on the application of 20-25 kg of pure nitrogen, the application amount of heavy superphosphate is 47.6-59.5 kg; the application amount of potassium sulfate is 39.2-49.0 kg.

[0016] Preferably, the dicyandiamide and N-butylthiophosphoric acid triamide are uniformly mixed with nitrogen fertilizer and then applied.

[0017] Another object of the present invention is to provide: application of the above method for improving cotton yield and nitrogen fertilizer utilization rate in cotton planting.

[0018] It can be seen from the above technical solution that compared with the prior art, the present invention has the following beneficial effects:

[0019] The invention combines nitrogen fertilizer with 1.5% to 3% of dicyandiamide in terms of the total weight of pure nitrogen in the nitrogen fertilizer and 1% to 2% of N-butylthiophosphoric acid triamide in terms of the total weight of pure nitrogen in the nitrogen fertilizer, and optimizes and improves other fertilization processes. The obtained method can significantly improve the yield of cotton, the apparent recovery rate of nitrogen fertilizer, and the agronomic utilization rate, and provides technical support for reducing nitrogen and increasing efficiency in cotton farmland production. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0021] Figure 1 The results are as follows: Effects of different nitrogen inhibitor treatments on cotton yield;

[0022] Figure 2 The effects of different nitrogen inhibitor treatments on the agronomic utilization efficiency of nitrogen fertilizer in cotton;

[0023] Figure 3 The effects of different nitrogen inhibitor treatments on the apparent recovery of nitrogen fertilizer in cotton;

[0024] Figure 4 The effect of different nitrogen inhibitors on the physiological utilization efficiency of nitrogen fertilizer in cotton. DETAILED DESCRIPTION

[0025] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0026] The potted plant experiments in the embodiments of the present invention were conducted at the potted plant field of the Cotton Research Institute of the Chinese Academy of Agricultural Sciences, Baibi Town, Anyang County, Anyang City, Henan Province (36°06'N, 114°21'E) from April to October 2021.

[0027] Example 1

[0028] A method for improving cotton yield and nitrogen fertilizer utilization rate comprises the following steps:

[0029] A pot experiment was conducted at the potted plant farm of the Cotton Research Institute of the Chinese Academy of Agricultural Sciences. During the experiment, the pots used were made of PVC material, with an upper inner diameter of 35 cm, a bottom inner diameter of 30 cm, and a height of 39 cm. Each pot was filled with 30 kg of soil. The effects of urea addition of three nitrification inhibitors (dicyandiamide (DCD), 3,4-dimethylpyrazole phosphate (DMPP) and 2-chloro-6-trimethylpyridine (CP)) and one urease inhibitor (N-butylthiophosphoric acid triamide (NBPT)) on cotton yield and nitrogen fertilizer utilization efficiency were studied. The specific experimental treatments are shown in Table 1. A total of 15 treatments were designed, and each treatment was repeated for 5 pots. No nitrogen fertilizer (CK) was used as a blank control. The amount of nitrogen fertilizer synergist was designed as the total amount according to Table 1, and two equal portions were weighed. The total amount of nitrogen (N) applied was 3g, which was applied twice in equal amounts as base fertilizer and topdressing during the initial flowering period. The amount of phosphorus (P2O5) and potassium (K2O) was 3g, and the amount of heavy calcium (P2O5 content was calculated as 0.42) per pot was 7.14g, and the amount of potassium sulfate (K2O content was calculated as 0.51) per pot was 5.88g. Heavy calcium and potassium sulfate were all applied at the bottom. Urease inhibitors and nitrification inhibitors were mixed and dissolved with urea according to the design in Table 1 and applied to the pots in equal amounts twice. The experimental potted plants were watered with equal amounts, and routine management such as pruning, chemical regulation, and pest and disease control referred to the local cotton high-yield management level. The nutrient branches and old leaves of cotton were collected, dried and weighed, and included in the dry weight of the whole cotton plant. Three healthy cotton plants were selected for each treatment, and the whole cotton plant samples were collected. The roots, stems, leaves, boll shells, and seed cotton (including unopened bolls) of each plant were dried and weighed, and the nitrogen absorption was determined by the Kjeldahl method. The growth period records the sowing period, seedling period, bud stage, flowering period, and boll stage. A growth survey (plant height, number of fruit branches, buds, flowers, bolls, and boll opening) is conducted in the middle of each month. The cotton yield is measured and analyzed later ( Figure 1 ), dry matter weight of each organ of a single plant (Table 2), nitrogen nutrient absorption and distribution of each organ of a single plant (Table 3), agronomic utilization rate of nitrogen fertilizer ( Figure 2 )、apparent recovery rate( Figure 3 ) and physiological availability ( Figure 4 ).

[0030] Table 1 Experimental design of adding urea to nitrogen fertilizer synergist

[0031]

[0032]

[0033] Depend on Figure 1 It can be seen that the cotton yields of treatments 3 (urea + 3% DCD), 10 (urea + 1.5% DCD + 1% NBP T), 13 (urea + 3% DCD + 2% NBPT), and 14 (urea + 3% CP + 2% NBPT) were significantly higher than that of treatment 1 with urea alone, and the cotton yield of treatment 13 was about 35.43% higher than that of treatment 1. After multiple comparisons, the difference between blank treatment CK and treatment 13 (3% DCD + 2% NBPT) reached an extremely significant level, indicating that urea combined with 3% DCD + 2% NBPT can significantly increase cotton yield. In treatment CK, treatment 1 (urea alone), treatment 2 (urea + 1.5% DCD), treatment 3 (urea + 3% DCD), treatment 4 (urea + 1.5% CP), treatment 5 (urea + 3% CP), treatment 6 (urea + 0.5% DMPP), treatment 7 (urea + 1% DMPP), treatment 8 (urea + 1% NBPT), and treatment 9 (urea + 2% NBPT), the cotton yield in the treatment with 2% NBPT was the highest, which was 40.60 g / plant, followed by treatment 8 and treatment 3. This shows that NBPT has the strongest effect on increasing cotton yield, DCD has a promoting effect on cotton yield, and CP and DMPP have no obvious effect on increasing cotton yield. The impact on cotton yield is NBPT>DCD>DMPP>CP.

[0034] Table 2 Effects of different treatments on cotton dry matter weight

[0035]

[0036]

[0037] As shown in Table 2, under the same soil total nitrogen content, the dry matter mass of the treatments with nitrogen fertilizer was significantly higher than that of the blank control. Under the same nitrogen application rate and soil total nitrogen content, the dry matter mass of seed cotton in treatment 10 (urea + 1.5% DCD + 1% NBPT), treatment 13 (urea + 3% DCD + 2% NBPT), and treatment 14 (urea + 3% CP + 2% NBPT) was significantly higher than that in treatment 1 with nitrogen fertilizer alone. Among them, the total dry matter mass per cotton plant in treatment 13 (urea + 3% DCD + 2% NBPT) was the highest, at 118.49 g / plant.

[0038] Table 3 Distribution of nitrogen content in various organs of cotton under different treatments

[0039]

[0040] As shown in Table 3, the nitrogen accumulation in the root, stem, leaf, boll and seed cotton was greater in the treatment with nitrogen fertilizer than in the treatment without nitrogen fertilizer, and the nitrogen accumulation in seed cotton in various organs of cotton was much greater than that in other organs. In the nitrogen absorption of untreated seed cotton, treatments 5 (urea + 3% CP), 10 (urea + 1.5% DCD + 1% NBPT), and 13 (urea + 3% DCD + 2% NBPT) were significantly higher than treatment 1 (urea alone). The total nitrogen content per plant in treatment 13 (urea + 3% DCD + 2% NBPT) was significantly higher than that in treatment 1 (urea alone), and the total nitrogen content per plant in cotton was about 2.3311 g.

[0041] Depend on Figure 2 It can be seen that treatment 10 (urea + 1.5% DCD + 1% NBPT), 13 (urea + 3% DCD + 2% NBPT) and treatment 1 (urea alone), treatment 2 (urea + 1.5% DCD), treatment 3 (urea + 3% DCD), treatment 4 (urea + 1.5% CP), treatment 5 (urea + 3% CP), treatment 6 (urea + 0.5% DMPP), treatment 7 (urea + 1% DMPP), treatment 11 (urea + 1.5% CP + 1% NBPT) There were significant differences between treatment 1 (urea + 1% DMPP + 2% NBPT) and treatment 15 (urea + 1% DMPP + 2% NBPT), indicating that the treatments of urea combined with 1.5% DCD + 1% NBPT and 3% DCD + 2% NBPT can significantly improve the agronomic utilization rate of nitrogen fertilizer in cotton. Among them, the agronomic utilization rate of nitrogen fertilizer in treatment 13 (urea + 3% DCD + 2% NBPT) was about 8.1%, indicating that when the nitrogen application rate was 3g, the combination of urea with 3% DCD + 2% NBPT had the most obvious effect on increasing cotton yield in this experiment.

[0042] Depend on Figure 3 It can be seen that the apparent recovery rate of cotton nitrogen fertilizer in 13 (urea + 3% DCD + 2% NBPT) is significantly higher than that in treatment 1 (urea alone), treatment 2 (urea + 1.5% DCD), treatment 3 (urea + 3% DCD), and treatment 6 (urea + 0.5% DMPP), which is about 39.34%. There is no significant difference among other treatments, indicating that in this experiment, urea combined with 3% DCD + 2% NBPT has the highest utilization rate of the applied nitrogen fertilizer.

[0043] Depend on Figure 4It can be seen that the physiological utilization rate of nitrogen fertilizer in cotton treated with urea alone and nitrification inhibitor or urease inhibitor was not significantly different from that in treatment 1 with urea alone. The yield increase of cotton seed fertilizer per unit nitrogen absorption was the highest in treatment 10 (urea + 1.5% DCD + 1% NBPT), which was 25.89 g / g. The physiological utilization rate of cotton nitrogen fertilizer in treatment 10 (urea + 1.5% DCD + 1% NBPT) was significantly higher than that in treatment 4 (urea + 1.5% CP), treatment 5 (urea + 3% CP), and treatment 7 (urea + 1% DMP P). This shows that the yield increase of cotton seed fertilizer per unit nitrogen absorption in treatment 10 was larger, while the yield increase of cotton seed fertilizer per unit nitrogen absorption in treatments 4, 5, and 7 was smaller, and the physiological utilization rate of cotton nitrogen fertilizer in the treatment of urea combined with 3% CP was the lowest.

[0044] In summary, under the same soil total nitrogen content and nitrogen application rate, urea combined with nitrification / urease inhibitors can increase cotton yield, and the effects of four nitrification / urease inhibitors on yield are NBPT>DCD>DMPP>CP. Among them, urea combined with 3% DCD+2% NBPT can significantly increase cotton yield. Seed cotton yield and nitrogen absorption increased with the increase in the level of nitrification / urease inhibitors. There was no significant difference in the total accumulation of dry matter between cotton treated with urea combined with nitrification / urease inhibitors and cotton treated with urea alone. The application of urea combined with 1.5% DCD+1% NBPT and 3% DCD+2% NBPT can significantly improve the agronomic utilization rate of nitrogen fertilizer in seed cotton, and the application of urea combined with 3% DCD+2% NBPT can significantly improve the apparent recovery rate of nitrogen fertilizer in seed cotton; the application of urea combined with nitrification / urease inhibitors had no significant effect on the physiological utilization rate of cotton, among which the physiological utilization rate of nitrogen fertilizer in the treatment with 1.5% DCD+1% NBPT was the highest, and the physiological utilization rate of nitrogen fertilizer in the treatment with 3% CP was the lowest.

[0045] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0046] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for improving cotton yield and nitrogen fertilizer utilization efficiency, characterized in that: When applying nitrogen fertilizer, based on the total weight of pure nitrogen contained in the nitrogen fertilizer, 1.5% to 3% of dicyandiamide and 1% to 2% of N-butylthiophosphoric acid triamide are applied.

2. The method for increasing cotton yield and nitrogen fertilizer utilization efficiency according to claim 1, characterized in that: When applying nitrogen fertilizer, based on the total weight of pure nitrogen contained in the nitrogen fertilizer, 1.5% to 3% of dicyandiamide and 2% of N-butylthiophosphoric acid triamide are applied.

3. The method for increasing cotton yield and nitrogen fertilizer utilization efficiency according to claim 1, characterized in that: The nitrogen fertilizer can be applied twice in equal amounts as base fertilizer and topdressing during the initial flowering period, or the base fertilizer and multiple topdressing can be applied in a certain proportion.

4. The method for increasing cotton yield and nitrogen fertilizer utilization efficiency according to claim 1, characterized in that: When applying nitrogen fertilizer as base fertilizer, a certain amount of phosphorus fertilizer and potassium fertilizer should be applied as well.

5. The method for increasing cotton yield and nitrogen fertilizer utilization rate according to claim 4, characterized in that: The phosphate fertilizer is triple superphosphate, wherein the P2O5 content is ≥42%; the potash fertilizer is potassium sulfate, wherein the K2O content is ≥51%.

6. The method for increasing cotton yield and nitrogen fertilizer utilization rate according to claim 5, characterized in that: Every 667m 2 Based on the application of 20-25 kg of pure nitrogen, the application amount of the heavy superphosphate is 47.6-59.5 kg; the application amount of the potassium sulfate is 39.2-49.0 kg.

7. The method for increasing cotton yield and nitrogen fertilizer utilization efficiency according to claim 1, characterized in that: The dicyandiamide and N-butylthiophosphoric acid triamide are uniformly mixed with nitrogen fertilizer and then applied.

8. Application of the method for improving cotton yield and nitrogen fertilizer utilization efficiency according to any one of claims 1 to 7 in cotton planting.

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