Soil conditioner for promoting growth of crops in saline-alkali soil and preparation method of soil conditioner

Abstract

The invention belongs to the technical field of soil improvement, and relates to a soil conditioner for promoting growth of crops in saline-alkali soil, which is characterized by comprising the following components: a nitrogen fertilizer, a phosphate fertilizer and a synergist in a ratio of (470-531): (65-107): (394-424), the nitrogen fertilizer comprises urea and ammonium sulfate in a mass ratio of (55-126): (344-459); the phosphate fertilizer comprises monoammonium phosphate, urea phosphate and ammonium polyphosphate in a mass ratio of (56-77): (3-27): (4-20); the synergist comprises a carbon source, a nitrification inhibitor and a biostimulant in a mass ratio of (390-420): (0.7-1.0): 3.3. The soil conditioner disclosed by the invention has the advantages of low cost and high benefit, is suitable for saline-alkali soil corn and cotton production, and remarkably solves the key problems of low nutrient utilization rate, low microbial activity and function and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of soil fertilizers and relates to a soil conditioner for promoting the growth of crops in saline-alkali land and a preparation method and application thereof. Technical Background

[0002] The improvement and utilization of saline-alkali land is a global problem. Saline-alkali soil is extremely unfavorable to crop production. First, a large amount of sodium ions in saline-alkali soil will lead to the deterioration of soil structure and poor soil ventilation and water permeability, affecting the respiration and absorption capacity of the root system. Secondly, a large amount of salt will increase the soil osmotic pressure, limit the water absorption capacity of plant roots, and even damage, dehydrate or die the root cells of plants. In addition, when the concentration of sodium, chlorine and other ions in the soil is too high, it will cause poisoning to plants, inhibit the normal physiological functions of plants, and cause disorders in the mineral metabolism of plants, making it difficult for plants to absorb elements such as phosphorus, iron and zinc. At the same time, ion competition will also affect the nutrient absorption of plant roots, leading to plant deficiency, slow growth, and reduced yields. Finally, high concentrations of salt and alkaline environment reduce the activity of soil microorganisms, affect the effective conversion of fertilizers and nutrient release, and reduce soil fertility and fertilizer utilization efficiency.

[0003] Salt-alkali stress has brought many challenges to the implementation of the fertilizer "control quantity and increase efficiency" strategy. The fertilizer "control quantity and increase efficiency" aims to ensure high grain yields, control fertilizer usage, and improve fertilizer utilization efficiency. However, salt-alkali stress will weaken the plant's nutrient absorption capacity, reduce nutrient utilization efficiency, and significantly reduce crop yields. In saline-alkali soils, nitrogen loss is serious, phosphorus is easily fixed, and nitrogen and phosphorus utilization efficiency is low. Therefore, in order to improve fertilizer utilization efficiency and increase crop yields, it is necessary to adjust the fertilization strategy on saline-alkali soils, use soil conditioners suitable for saline-alkali soils, improve soil structure, improve nutrient efficiency, and ensure high crop yields.

[0004] However, the traditional understanding that "too much salt eats fertilizer, and too much fertilizer eats salt" can no longer meet the current production needs. The large-scale application of chemical fertilizers may aggravate soil salinization and further reduce fertilizer utilization efficiency. The current fertilizer products suitable for saline-alkali land have the following problems: 1. They are not very targeted. Existing fertilizers are usually designed for non-saline-alkali soils, and there are no personalized fertilizer products developed for the characteristics of saline-alkali soils; 2. The effect of improving nutrient efficiency on saline-alkali land is limited; 3. Existing fertilizers or improvers focus on improving soil, and do not target crop characteristics to improve crop adaptability to saline-alkali soils; 4. The biological potential of crop salt tolerance is difficult to play. Therefore, there is an urgent need to develop a soil conditioner suitable for saline-alkali soil crop production that can not only provide effective nutrients for crops, but also reduce salt stress and play the biological potential of crop salt resistance and efficient nutrient utilization. Summary of the invention

[0005] In response to the above problems, the inventors have developed a low-cost, high-efficiency soil conditioner suitable for corn and cotton production in saline-alkali soils. It significantly solves key problems such as low nutrient utilization rate and low microbial activity and function, and can improve saline-alkali land production capacity and crop nutrient utilization efficiency. Compared with the existing technology, it has certain innovation and application prospects.

[0006] A soil conditioner for promoting the growth of crops in saline-alkali land, characterized in that it comprises the following components: nitrogen fertilizer, phosphate fertilizer and synergist, the ratio of which is 470-531:65-107:394-424, wherein:

[0007] Nitrogen fertilizer, including urea and ammonium sulfate, with a mass ratio of 55-126:344-459;

[0008] Phosphate fertilizer, comprising monoammonium phosphate, urea phosphate and ammonium polyphosphate in a mass ratio of 56-77:3-27:4-20;

[0009] The synergist comprises a carbon source, a nitrification inhibitor and a biostimulant, and the mass ratio is 390-420:0.7-1.0:3.3.

[0010] The soil conditioner for promoting the growth of crops in saline-alkali land of the present invention is described in detail below. Among the components of the conditioner, the nitrogen fertilizer is urea and ammonium sulfate; the phosphorus fertilizer is monoammonium phosphate, urea phosphate and ammonium polyphosphate; the synergist contains a carbon source, a nitrification inhibitor and a biostimulant; the carbon source is at least one of molasses and citric acid; the nitrification inhibitor is at least one selected from 2-chloro-6-(trichloromethyl)pyridine, dicyandiamide and 3,4-dimethylpyrazole phosphate; the biostimulant is at least one selected from fructose, luteolin and myristic acid.

[0011] It should be noted that the total weight parts of the nitrogen fertilizer, phosphorus fertilizer and synergist of the present invention are calculated based on 1000 parts, that is, the measurement of each type of fertilizer is based on 1000 parts and is calculated according to the key proportion of the actual object.

[0012] The nitrogen fertilizer of the present invention is urea and ammonium sulfate, and the mass proportion of the nitrogen fertilizer in the total mass of the improver is 470-531 parts. In the present invention, the mass ratio of urea to ammonium sulfate in the nitrogen fertilizer is preferably 55-126:344-459. The ammonium sulfate in the nitrogen fertilizer of the present invention can not only supplement soil nitrogen and sulfur elements, but also acidify the root zone of crops, increase salt leaching, and promote the absorption and utilization of phosphorus and trace elements by plants. By compounding the above-mentioned dose of ammonium sulfate and urea, the solubility of phosphorus in the soil is increased through acidification, and the utilization rate of phosphorus is improved. Moreover, the soil improver for promoting the growth of crops in saline-alkali land of the present invention can reduce the amount of phosphorus fertilizer applied.

[0013] The phosphate fertilizers described in the present invention are monoammonium phosphate, urea phosphate and ammonium polyphosphate, and the mass fraction of the phosphate fertilizers in the total mass of the improver is 65 to 107 parts. In the present invention, the mass ratio of monoammonium phosphate, urea phosphate and ammonium polyphosphate in the phosphate fertilizers is 56 to 77:3 to 27:4 to 20. The monoammonium phosphate and urea phosphate in the phosphate fertilizers described in the present invention can not only supplement the soil phosphorus element, but also acidify the soil and alleviate saline-alkali stress. By matching the monoammonium phosphate and urea phosphate of the quick-acting phosphate fertilizers with the ammonium polyphosphate of the slow-acting phosphate fertilizer, the nutrient supply intensity can be maintained for a long time, the nutrient absorption of crops can be promoted, and the phosphorus utilization efficiency can be improved. The soil improver for promoting the growth of crops in saline-alkali land described in the present invention can reduce the amount of phosphate fertilizer applied.

[0014] The synergist of the present invention contains a carbon source, a nitrification inhibitor and a biostimulant, the mass fraction of the synergist in the total mass of the improver is 394-424 parts, and the mass ratio of the carbon source, the nitrification inhibitor and the biostimulant in the synergist of the present invention is 390-420:0.7-1.0:3.3. The synergist in the soil improver of the present invention makes a great contribution to the activation of inactive phosphorus in the soil.

[0015] The carbon source described in the present invention is at least one of molasses and citric acid, preferably molasses and citric acid. In the present invention, when the carbon source is molasses and citric acid, the mass ratio of molasses and citric acid in the carbon source is preferably 383-413:6.6. Suitable carbon sources and biostimulants promote the growth and reproduction of microorganisms, improve the activity of soil microorganisms, and phosphate-solubilizing bacteria secrete a variety of organic acids and protons, which can lower the pH value of the environment to dissolve inorganic phosphorus, and secrete alkaline phosphatase to dissolve organic phosphorus, thereby increasing the content of available phosphorus in the soil. In addition, nitrification inhibitors can also reduce the conversion of ammonium nitrogen fertilizers to nitrate nitrogen, so that the effect of ammonium nitrogen acidifying the rhizosphere can be maintained for a longer time and at a higher intensity.

[0016] The nitrification inhibitor of the present invention is at least one of 2-chloro-6-(trichloromethyl)pyridine, dicyandiamide and 3,4-dimethylpyrazole phosphate.

[0017] The biostimulant of the present invention is at least one of fructose, luteolin and myristic acid, preferably containing fructose, luteolin and myristic acid. In the present invention, the mass ratio of myristic acid, fructose and luteolin in the biostimulant is 1.3:1:1. The luteolin of the present invention can stimulate the spore germination of arbuscular mycorrhizal fungi in the soil, myristic acid can provide nutrition for the infection of arbuscular mycorrhizal fungi in the soil, and help arbuscular mycorrhizal fungi to colonize the root system better and faster, and fructose can activate the phosphorus solubilization function of rhizosphere and mycelium microorganisms, thereby helping plants to better absorb nitrogen and phosphorus nutrients.

[0018] The present invention also provides the use of the soil conditioner of the above scheme in soil improvement and / or promoting plant growth. In the present invention, the soil preferably includes saline-alkali soil; and the plants are preferably cotton and corn.

[0019] The present invention also provides a method for applying a soil conditioner for promoting the growth of crops in saline-alkali land, comprising: applying the soil conditioner described in the above scheme to the saline-alkali soil, that is, applying it as a base before sowing or applying it with water drops after seedlings emerge.

[0020] In the present invention, the soil conditioner application method preferably includes basal application or drip irrigation.

[0021] When the application method described in the present invention is preferably basal application, the total mass parts of nitrogen and phosphorus in the soil conditioner are 596-606, and the ratio of nitrogen fertilizer to phosphorus fertilizer is 502-531:65-103; the mass ratio of urea and ammonium sulfate is 55-72:447-459; the mass ratio of monoammonium phosphate, urea phosphate and ammonium polyphosphate in the phosphate fertilizer is 56-58:3-27:4-20; the mass ratio of the carbon source, nitrification inhibitor and biostimulant is 390-400:0.9-1.0:3.3; the mass ratio of molasses and citric acid in the carbon source is 383-394:6.6; the nitrification inhibitor includes 3,4-dimethylpyrazole phosphate; the mass ratio of myristic acid, fructose and luteolin in the biostimulant is 1.3:1:1.

[0022] Beneficial Effects

[0023] The new soil conditioner provided by the present invention, i.e., a soil conditioner for promoting the growth of crops in saline-alkali land, has the following beneficial effects:

[0024] 1. When the topsoil cannot be completely desalinated, ammonium nitrogen fertilizer can be used to acidify the rhizosphere, reduce salt stress, and improve crop salt tolerance and yield;

[0025] 2. By mixing fast-acting and slow-acting phosphate fertilizers, phosphorus fixation in the root zone can be reduced, nutrient supply intensity can be maintained, and crop growth and nutrient absorption can be promoted;

[0026] 3. By compounding carbon sources and biostimulants into synergists, indigenous microorganisms are jointly regulated to promote the activation and turnover of soil nutrients mediated by microorganisms on the one hand, and to improve crop salt tolerance through microbial processes on the other. DETAILED DESCRIPTION

[0027] In order to further illustrate the present invention, a saline-alkali soil conditioner and its application provided by the present invention are described in detail below in conjunction with the examples, but they should not be understood as limiting the scope of protection of the present invention. The following examples are only used to illustrate the present invention and are not intended to limit the scope of protection of the present invention. The test methods used in the following examples are conventional methods unless otherwise specified. The raw materials used in the following examples can all be obtained from commercial sources.

[0028] Example 1

[0029] With 1000 g as the total mass, a soil conditioner was prepared according to the following composition:

[0030] Urea 125.8g, ammonium sulfate 344.3g, monoammonium phosphate 76.2g, urea phosphate 14.1g, ammonium polyphosphate 16.0g, molasses 413.0g, citric acid 6.6g, 3,4-dimethylpyrazole phosphate 0.7g, myristic acid 1.3g, fructose 1.0g, luteolin 1.0g.

[0031] Example 2

[0032] With 1000 g as the total mass, a soil conditioner was prepared according to the following composition:

[0033] Urea 55.3g, ammonium sulfate 447.5g, monoammonium phosphate 56.6g, urea phosphate 26.2g, ammonium polyphosphate 19.8g, molasses 383.6g, citric acid 6.6g, 3,4-dimethylpyrazole phosphate 1.1g, myristic acid 1.3g, fructose 1.0g, luteolin 1.0g.

[0034] Example 3

[0035] With 1000 g as the total mass, a soil conditioner was prepared according to the following composition:

[0036] Urea 71.7g, ammonium sulfate 458.6g, monoammonium phosphate 58.0g, urea phosphate 3.6g, ammonium polyphosphate 4.1g, molasses 393.2g, citric acid 6.6g, 3,4-dimethylpyrazole phosphate 0.9g, myristic acid 1.3g, fructose 1.0g, luteolin 1.0g.

[0037] Comparative Example 1

[0038] With 1000 g as the total mass, a soil conditioner was prepared according to the following composition as a high phosphorus control group:

[0039] Urea 228.6g, ammonium sulfate 190.1g, monoammonium phosphate 100.9g, urea phosphate 9.3g, ammonium polyphosphate 4.7g, molasses 456.1g, citric acid 6.6g, 3,4-dimethylpyrazole phosphate 0.4g, myristic acid 1.3g, fructose 1.0g, luteolin 1.0g.

[0040] Comparative Example 2

[0041] With 1000 g as the total mass, a soil conditioner was prepared according to the following composition as a low-phosphorus control group:

[0042] Urea 243.8g, ammonium sulfate 195.5g, monoammonium phosphate 57.7g, urea phosphate 13.3g, ammonium polyphosphate 10.1g, molasses 469.3g, citric acid 6.6g, 3,4-dimethylpyrazole phosphate 0.4g, myristic acid 1.3g, fructose 1.0g, luteolin 1.0g.

[0043] Comparative Example 3

[0044] Blank control, no soil amendment was applied.

[0045] In the following application examples 1, 2, 3 and 4, the soil conditioners of the above-mentioned examples 1, 2, 3, comparative examples 1 and 2 are all determined in final dosage according to 75 mg P / kg soil. The basic soil of all application examples is added with basic nutrients according to 200 mg / kg N (urea), 200 mg / kg K (potassium sulfate), 50 mg / kg Mg (magnesium sulfate heptahydrate), 5 mg / kg Zn (zinc sulfate heptahydrate), 5 mg / kg Mn (manganese sulfate) and 2 mg / kg Cu ​​(copper sulfate pentahydrate). Urea contains 46% nitrogen; ammonium sulfate contains 21% nitrogen; monoammonium phosphate contains 12% nitrogen and 61% P2O5; urea phosphate contains 17% nitrogen and 44% P2O5; ammonium polyphosphate contains 18% nitrogen and 58% P2O5; and molasses contains 30% carbon. In Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2 and Comparative Example 3, the total amount of nutrients introduced by the basic nutrients and the soil conditioner is shown in Table 1. The initial salt content of the test soil was 1.00 g / kg. In Application Example 1, sodium chloride was added to the soil to make the salt content reach 2.5 g / kg. In Application Examples 2-4, sodium chloride was added to the soil to make the salt content reach 1.50 g / kg.

[0046] Table 1 Total nutrient input and soil conditioner dosage in Examples and Comparative Examples

[0047]

[0048] Application Example 1

[0049] From June to August 2022, a potted plant experiment was carried out with cotton (Gossypium hirsutum) Xinlu Zao No. 57 as the object. After the cotton seeds were disinfected, they were placed in the dark at 28°C for germination. After culturing for about 12 hours, the seeds can be sown when they turn white. The soil conditioner of Examples 1, 2, 3 and Comparative Examples 1 and 2 was dissolved in 450 mL of water and poured into the pot (the field water holding capacity was about 60% at this time). After the water has completely infiltrated, sowing was carried out, and then the soil was covered and covered with plastic film to retain water and heat. The plastic film was uncovered 2 to 3 days after sowing. The seedlings were determined in about a week, and 3 cotton plants were retained in each pot. During the growth of cotton, water was supplemented at a weight water content of 18%.

[0050] The leaf area of ​​cotton was measured on the 70th day after sowing. The SPAD value of cotton leaves was measured on the 61st, 79th and 82nd day after sowing, and cotton was harvested on the 87th day after sowing. The aboveground part was collected, and the aboveground part samples were dried in an oven at 105°C for 30 minutes, and the oven temperature was adjusted to 65°C to 70°C until it was dried to constant weight. The dry weight was weighed and recorded, and the results are shown in Table 2.

[0051] Results Analysis

[0052] It can be seen from the results in Table 2 that the application of the soil conditioner in each embodiment in saline-alkali soil significantly promoted the growth of cotton (Table 2). The total leaf area of ​​Example 1 and Example 2 increased by 42.4% and 43.4% respectively compared with that of Comparative Example 1, and the total leaf area of ​​Example 3 increased by 8.3% compared with that of Comparative Example 2. 61 days after sowing, the SPAD values ​​of Example 1 and Example 2 increased by 0.5% and 3.9% respectively compared with that of Comparative Example 1, and the SPAD value of Example 3 increased by 5.0% compared with that of Comparative Example 2. 79 days after sowing, the SPAD values ​​of Example 1 and Example 2 increased by 8.6% and 5.8% respectively compared with that of Comparative Example 1, and the SPAD value of Example 3 increased by 3.2% compared with that of Comparative Example 2. 82 days after sowing, the SPAD values ​​of Example 1 and Example 2 increased by 5.3% and 2.9% respectively compared with that of Comparative Example 1, and the SPAD value of Example 3 increased by 3.1% compared with that of Comparative Example 2. The biomass of Example 1 and Example 2 were increased by 16.0% and 17.3% respectively compared with that of Comparative Example 1, and the SPAD value of Example 3 was increased by 13.1% compared with that of Comparative Example 2.

[0053] Table 2 Analysis of cotton leaf area, SPAD value and biomass in Examples 1 to 3 and Comparative Examples 1 to 3

[0054]

[0055] Note: The average value refers to the average value of 3 repetitions for each treatment. The nitrogen and phosphorus input amounts of Examples 1 and 2 and Comparative Example 1 are equal; the nitrogen and phosphorus input amounts of Example 3 and Comparative Example 2 are equal.

[0056] Application Example 2

[0057] A potted plant test was carried out from June to August 2022, and the crop planted was corn Zhengdan No. 958 (Zea mays L.cvZhengdan No.958). After disinfection, the corn seeds were placed in the dark at 28°C for germination. They can be sown after about 12 hours of cultivation. The soil conditioner of Examples 1, 2, 3 and Comparative Examples 1 and 2 was dissolved in 450 mL of water and poured into the pot (the field water holding capacity was about 60% at this time). After the water has completely infiltrated, sowing was carried out, and then the soil was covered and covered with plastic film to retain water and heat. The plastic film was uncovered after 2 to 3 days of sowing. The seedlings were fixed in about a week, and 3 test corns were left. During the test, the soil moisture content was maintained at 18% (about 60% of the field water holding capacity).

[0058] The plant diameter was measured on the 23rd and 60th day after sowing; the corn leaf area was counted on the 55th day after sowing; the corn leaf SPAD value was measured on the 58th day after sowing; and the corn was harvested on the 62nd day after sowing. The aboveground plants were collected and weighed for fresh weight, and the aboveground samples were dried in an oven at 105°C for 30 minutes, and the oven temperature was adjusted to 65°C-70°C until they were dried to constant weight. The dry weight was weighed and recorded, and the results are shown in Table 3.

[0059] Results Analysis

[0060] It can be seen from the results in Table 3 that the application of the soil conditioner in each embodiment in saline-alkali soil significantly promoted the growth of corn. On the 23rd day after sowing, the diameters of Example 1 and Example 2 were increased by 21.0% and 27.2% respectively compared with Comparative Example 1, and the diameter of Example 3 was increased by 26.8% compared with Comparative Example 2. On the 60th day after sowing, the diameters of Example 1 and Example 2 were increased by 2.5% and 6.0% respectively compared with Comparative Example 1, and the diameter of Example 3 was increased by 22.5% compared with Comparative Example 2. The total leaf area of ​​Example 1 and Example 2 was increased by 21.36% and -2.1% respectively compared with Comparative Example 1, and the total leaf area of ​​Example 3 was increased by 34.4% compared with Comparative Example 2. The SPAD value of Example 3 was increased by 13.8% compared with Comparative Example 2. The plant heights of Example 1 and Example 2 were increased by 0% and 2.3% respectively compared with Comparative Example 1, and the SPAD value of Example 3 was increased by 7.7% compared with Comparative Example 2. The biomass of Example 1 and Example 2 increased by 10.1% and 10.7% respectively compared with that of Comparative Example 1, and the biomass of Example 3 increased by 98.9% compared with that of Comparative Example 2.

[0061] Table 3 Analysis of corn diameter, leaf area, plant height and biomass in Examples 1 to 3 and Comparative Examples 1 to 3

[0062]

[0063] Note: The average value refers to the average value of 3 repetitions for each treatment. The nitrogen and phosphorus input amounts of Examples 1 and 2 and Comparative Example 1 are equal; the nitrogen and phosphorus input amounts of Example 3 and Comparative Example 2 are equal.

[0064] Application Example 3

[0065] A potted plant experiment was conducted from September to November 2022, and the crop planted was corn Zhengdan No. 958 (Zea mays L.cvZhengdan No.958). After disinfection, corn seeds were placed in the dark at 28°C for germination. They can be sown after about 12 hours of cultivation. Eight corn seeds were sown in each pot, and then covered with soil and covered with plastic film to retain water and heat. The plastic film was uncovered 2 to 3 days after seeding. The seedlings were fixed in about a week, and 3 test corns were left. During the experiment, the soil moisture content was maintained at 18% (about 60% of the field water holding capacity). The soil conditioner was applied by drip irrigation. The drip irrigation potted plant experiment used a water-saving drip irrigation device to dissolve the soil conditioner in water and then hang it in the pot. The specific operation steps are: dilute the soil conditioner with water and add it to the drip bag, hang it above the potted soil, use gravity to replace the pipeline pressure of the drip irrigation equipment in agricultural production, and add a small rate regulator in the middle of the water pipe to connect it to the dripper to control the drip irrigation rate. The soil conditioner was applied four times, drip-applied on September 21, October 5, October 12, and October 30, with the application ratio of 8:8:51:33.

[0066] The leaf area of ​​corn was measured on the 22nd day after sowing, the plant height was measured on the 40th and 53rd day after sowing, the leaf SPAD value was measured on the 60th day after sowing, and the harvest was carried out. The aboveground plants were collected and weighed for fresh weight, and the aboveground samples were dried in an oven at 105°C for 30 minutes, and then dried at 65°C to 70°C until constant weight was reached. The dry weight was weighed and recorded, and the results are shown in Table 4.

[0067] Results Analysis

[0068] It can be seen from the results of Table 4 that drip application of the soil conditioner in each embodiment in saline-alkali soil significantly promoted the growth of corn. On the 40th day after sowing, the plant height of Example 1 and Example 2 increased by 11.3% and 11.6% respectively compared with Comparative Example 1, and the plant height of Example 3 increased by 11.4% compared with Comparative Example 2. On the 53rd day after sowing, the plant height of Example 1 and Example 2 increased by 29.7% and 26.3% respectively compared with Comparative Example 1. The total leaf area of ​​Example 1 and Example 2 increased by 14.1% and 4.6% respectively compared with Comparative Example 1, and the total leaf area of ​​Example 3 increased by 7.9% compared with Comparative Example 2. The SPAD values ​​of Example 1 and Example 2 increased by 15.1% and 13.7% respectively compared with Comparative Example 1, and the SPAD value of Example 3 increased by 3.2% compared with Comparative Example 2. The biomass of Example 1 and Example 2 increased by 49.5% and 35.5% respectively compared with Comparative Example 1, and the biomass of Example 3 increased by 18.7% compared with Comparative Example 2.

[0069] Table 4 Analysis of corn plant height, leaf area, SPAD value and biomass in Examples 1 to 3 and Comparative Examples 1 to 3

[0070]

[0071] Note: The average value refers to the average value of 3 repetitions for each treatment. The nitrogen and phosphorus input amounts of Examples 1 and 2 and Comparative Example 1 are equal; the nitrogen and phosphorus input amounts of Example 3 and Comparative Example 2 are equal.

[0072] Application Example 4

[0073] A potted plant experiment was conducted from October to December 2022, and the crop planted was corn Zhengdan No. 958 (Zea mays L.cv Zhengdan No. 958). After disinfection, the corn seeds were placed in the dark at 28°C for germination. They can be sown after about 12 hours of cultivation. Eight corn seeds were sown in each pot, and then covered with soil and covered with plastic film to retain water and heat. The plastic film was uncovered 2 to 3 days after seeding. The seedlings were fixed in about a week, and 3 test corns were left. During the experiment, the soil moisture content was maintained at 18% (about 60% of the field water holding capacity). The soil conditioner was applied by drip irrigation. The drip irrigation potted plant experiment used a water-saving drip irrigation device to dissolve the soil conditioner in water and then hang it in the pot. The specific operating steps are: dilute the soil conditioner with water and add it to the drip bag, hang it above the potted soil, use gravity to replace the pipeline pressure of the drip irrigation equipment in agricultural production, and add a small rate regulator in the middle of the water pipe to connect it to the dripper to control the drip irrigation rate. The soil conditioner was applied 4 times, with an interval of 7-10 days between each application, and the application ratio of each time was 8:8:51:33.

[0074] Maize plant height was measured 16, 31, 35, and 41 days after sowing;

[0075] The SPAD value of maize leaves was measured 16 days after sowing;

[0076] On the 42nd day after sowing, the yellowing degree of the first leaf of corn was counted. The overall yellowing degree of leaves was divided into 5 levels, from 1 to 5, ranging from mild yellowing of small leaves to severe yellowing and withering of large leaves. The yellowing degree of corn leaves was recorded as the salt stress index, and the formula is shown in Formula I:

[0077]

[0078] The test was conducted 42 days after corn was sown. The aboveground plants were harvested and weighed for fresh weight. The aboveground samples were dried in an oven at 105°C for 30 minutes, and the oven temperature was adjusted to 65°C to 70°C until the plants were dried to a constant weight. The dry weight was weighed and recorded. The results are shown in Table 5.

[0079] Results Analysis

[0080] It can be seen from the results in Table 5 that the soil conditioner of the embodiment applied by dripping in saline-alkali soil significantly promoted the growth of corn. On the 16th day after sowing, the plant heights of Example 1 and Example 2 increased by 1.0% and 5.2% respectively compared with Comparative Example 1, and the plant height of Example 3 increased by 15.5% compared with Comparative Example 2. On the 31st day after sowing, the plant heights of Example 1 and Example 2 increased by 2.3% and 4.2% respectively compared with Comparative Example 1, and the plant height of Example 3 increased by 6.8% compared with Comparative Example 2. On the 35th day after sowing, the plant heights of Example 1 and Example 2 increased by 13.2% and 9.0% respectively compared with Comparative Example 1, and the plant height of Example 3 increased by 19.1% compared with Comparative Example 2. On the 41st day after sowing, the plant heights of Example 1 and Example 2 increased by 10.7% and 2.6% respectively compared with Comparative Example 1, and the plant height of Example 3 increased by 19.9% ​​compared with Comparative Example 2. The SPAD values ​​of Example 1 and Example 2 were increased by 13.8% and 14.4% respectively compared with Comparative Example 1, and the SPAD value of Example 3 was increased by 51.4% compared with Comparative Example 2. The salt stress index of Example 2 was reduced by 33.0% compared with Comparative Example 1, and the salt stress index of Example 3 was reduced by 92.9% compared with Comparative Example 2. The biomass of Example 1 and Example 2 were increased by 51.1% and 47.6% respectively compared with Comparative Example 1, and the biomass of Example 3 was increased by 48.9% compared with Comparative Example 2.

[0081] Table 5 Analysis of corn plant height, SPAD value, salt stress index and biomass in Examples 1 to 3 and Comparative Examples 1 to 3

[0082]

[0083] Note: The average value refers to the average value of 3 repetitions for each treatment. The nitrogen and phosphorus input amounts of Examples 1 and 2 and Comparative Example 1 are equal; the nitrogen and phosphorus input amounts of Example 3 and Comparative Example 2 are equal.

[0084] In summary, after applying the soil conditioners of each embodiment and each comparative example in the above application examples, it can be known that the soil conditioner described in the present invention cooperates with urea and ammonium sulfate to increase the solubility of phosphorus in the soil by acidification, while promoting the reduction of rhizosphere salinity, alleviating salt stress, and increasing crop yields; and by matching the quick-acting phosphate fertilizer monoammonium phosphate, urea phosphate and the slow-acting phosphate fertilizer ammonium polyphosphate, the soil phosphorus supply capacity is improved, the phosphorus nutrient fixation in the root zone is reduced, the nutrient supply intensity is maintained, and the crop growth and nutrient absorption are promoted; and the soil microbial function is strengthened by matching the carbon source and the biostimulant. It can be seen from the above application examples 1-3 that the soil conditioner applied in each embodiment of the present invention can stimulate the activity of soil microorganisms, improve the soil pH, and promote nutrient turnover. Applying the soil conditioner described in the present invention on salinized soil can promote crop growth. It can be seen that the soil conditioner for promoting the growth of crops in saline-alkali land of the present invention has a very broad application prospect in agricultural production.

[0085] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A soil conditioner for promoting the growth of crops in saline-alkali land, characterized in that: It includes the following components: nitrogen fertilizer, phosphorus fertilizer and synergist, the ratio of which is 470-531:65-107:394-424, among which: Nitrogen fertilizer, including urea and ammonium sulfate, with a mass ratio of 55-126:344-459; Phosphate fertilizer, comprising monoammonium phosphate, urea phosphate and ammonium polyphosphate in a mass ratio of 56-77:3-27:4-20; The synergist comprises a carbon source, a nitrification inhibitor and a biostimulant, and the mass ratio is 390-420:0.7-1.0:3.

3.

2. The soil conditioner for promoting the growth of crops in saline-alkali land according to claim 1, characterized in that: The carbon sources in the synergist are molasses and citric acid, and the mass ratio is 383-413:6.

6.

3. The soil conditioner for promoting the growth of crops in saline-alkali land according to claim 1, characterized in that: The nitrification inhibitor is one selected from 2-chloro-6-(trichloromethyl)pyridine, dicyandiamide and 3,4-dimethylpyrazole phosphate.

4. The soil conditioner for promoting the growth of crops in saline-alkali land according to claim 1, characterized in that: The biostimulant is at least one of fructose, luteolin and myristic acid. When all three are contained, the mass ratio thereof is 1.3:1:

1.

5. A method for applying a soil conditioner for promoting the growth of crops in saline-alkali land, characterized in that: Apply as basal fertilizer before sowing or as drip fertilizer after emergence.

6. The method for applying a soil conditioner according to claim 5, characterized in that: The application methods are basal application and drip irrigation.

7. The method for applying a soil conditioner according to claim 5, characterized in that: The application rate of soil conditioner is 81-127 kg per mu.

8. An application of a soil conditioner for promoting the growth of crops in saline-alkali land, characterized in that: The soil conditioner according to any one of claims 1 to 3 is applied to cotton and corn at various growth stages.

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