Construction method and application of rhizosphere suitable microdomain of corn in saline-alkali soil

Abstract

The invention discloses a saline-alkali soil corn rhizosphere suitable micro-domain construction method and application, and relates to the field of saline-alkali soil crop rhizosphere soil environment optimizing.According to saline-alkali soil corn rhizosphere suitable micro-domain construction, a straw interlayer, a fertile plough layer and a cultivation layer are arranged in a cultivated land salinization soil layer, so that saline-alkali soil structure optimization can be achieved; meanwhile, reduction of saline-alkali salt of cultivated land is accelerated, salt resistance of surface soil is inhibited, and suitable microdomain construction of corn rhizosphere and high yield of corn cultivation are achieved. Practice shows that the construction method of the corn rhizosphere suitable microdomain can optimize the soil structure and environment of the saline-alkali cultivated land and promote the construction of a good rhizosphere environment of the corn. The invention provides a saline-alkali soil corn rhizosphere suitable micro-domain structure, which comprises a straw interlayer, a fertile plough layer and a cultivation layer, and can promote saline-alkali soil corn rhizosphere suitable micro-domain salt inhibition, prevent salt return, promote saline-alkali soil soil structure and fertility optimization, and realize saline-alkali soil corn high-yield cultivation.

Description

Technical Field

[0001] The present invention relates to the technical field of constructing a rhizosphere suitable micro-region for crops in saline-alkali land, and more specifically, to a method for constructing a rhizosphere suitable micro-region for maize in saline-alkali land and its application in high-yield maize cultivation. Background Art

[0002] Cultivated land salinization can promote soil compaction, reduce the content of available nutrients and organic matter in the soil, reduce soil biodiversity and soil productivity, thus affecting the normal growth and development of crops and even leading to yield reduction. In recent years, with the continuous strengthening of China's attention to the improvement and utilization of salinized cultivated land, governments at all levels in China have mobilized relevant practitioners to continuously carry out research and promote improvement measures, and many significant progress have been made. However, due to the poor stability of saline-alkali soil after improvement and its high susceptibility to recurrence, the treatment cycle of saline-alkali soil is long and the cost is high. The technical support for efficiently improving cultivated land salinization is yet to be strengthened, and problems such as weak and stunted growth, easy withering, seedling gaps and lodging of maize cultivated in saline-alkali land are urgently to be solved. Summary of the Invention

[0003] In view of this, the present invention provides a method for constructing a rhizosphere suitable micro-region for maize in saline-alkali land and its application. This method can realize the construction of a rhizosphere suitable micro-region environment for maize in saline-alkali land, eliminate soil compaction in the rhizosphere micro-region of maize, resist the interference of high salt content on maize growth, improve soil physical properties, and increase the content of available nutrients in the soil.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for constructing a rhizosphere suitable micro-region for maize in saline-alkali land, comprising the following steps:

[0006] (1) After rotary tillage with a straw injection type returning machine in salinized cultivated land, inject straw into the deep soil to form a straw interlayer;

[0007] (2) Apply polyurethane coated controlled release fertilizer, chemical fertilizer, organic materials and maize seeds together in a strip shape into the soil with a seed fertilizer drill to form a fertile plough layer;

[0008] (3) Spray salt-tolerant biological functional substances on the surface layer of saline-alkali land soil and then cover with a film to form a cultivation layer.

[0009] Preferably, in step (1), the rotary tillage depth is 30 - 40 cm, the straw injection depth is 30 cm - 40 cm, the thickness of the straw interlayer is 10 - 20 cm, and the straw length is 1 - 2 cm.

[0010] Preferably, in step (2), the fertilizer application depth is 15 - 20 cm, the sowing depth is 3 - 5 cm, and the distance between the fertilizer and the seeds is 8 - 10 cm.

[0011] Preferably, the nutrient content of the polyurethane-coated controlled-release fertilizer is N-P 2 O 5 -K 2 O: 15-7-4. The hydrostatic release period of the polyurethane-coated controlled-release fertilizer is 60 days, and the application rate of the polyurethane-coated controlled-release fertilizer is 100-120 kg·ha -1 。

[0012] Preferably, the organic materials include one or more of earthworm castings, cow dung, biochar, humic acid, or furfural residue, and the application rate of the organic materials is 35-45 t·ha -1 。

[0013] Preferably, the chemical fertilizers and their application rates in step (2) include 15-20 kg N / ha of ammonium sulfate -1 , 30-35 kg N / ha of urea -1 , 3-5 kg P 2 O 5 / ha -1 , 3-5 kg P 2 O 5 / ha -1 , 15-20 kg P 2 O 5 / ha -1 。

[0014] Preferably, the salt-tolerant bio-functional substances in step (3) include one or more of polypeptide trace element water-soluble fertilizers, seaweed polypeptides, amino acids, seaweed polysaccharides, or agricultural phages, and the dosage is 30-50 L / ha -1 , and it is diluted with water at a ratio of 1:500-1:1000 when used.

[0015] Preferably, in step (3), the film covering uses plastic film or liquid plastic film, and the film covering spacing is 10-20 cm.

[0016] Preferably, it further includes step (4): 5-8 days after sowing, the corn emerges. Open a 2-3 cm break in the covered plastic film, take out the corn seedlings, and cover the break with soil.

[0017] The present invention also provides the application of the method as described in the above technical solution in high-yield corn planting.

[0018] It can be seen from the above technical solutions that compared with the prior art, the present invention discloses a method for constructing a rhizosphere suitable micro-region for corn in saline-alkali land and its application, and has the following beneficial effects:

[0019] The present invention injects straw into the deep soil by using an injection-type straw returning machine for rotary tillage during the maize cultivation season in saline-alkali land, forming a straw interlayer. Through rotary tillage, the plow sole of the saline-alkali soil is broken, the physical structure of the soil is improved, the water retention and moisture preservation capacity of the soil is enhanced, and at the same time, straw is injected to block the accumulation of salt in the salinized soil, inhibit the salt return on the surface of the saline-alkali soil, and increase the organic matter content of the soil; the fertile plow layer enables the soil to stably and continuously supply the nutrients required for maize growth by adding polyurethane-coated slow-release fertilizers, promoting the growth and development of maize; the organic materials can promote the balanced and comprehensive supply of soil nutrients, and at the same time promote the decomposition of straw, promote the improvement of soil organic matter, realize fertile soil for rooting, and through strip fertilization, promote the elongation of maize roots and nutrient acquisition, reduce fertilizer loss and waste, and at the same time reduce the risk of environmental pollution; through a combined seeding and fertilizing machine, fertilization and seeding are carried out simultaneously, improving the seeding and fertilizing efficiency, increasing the economic benefits while reducing the cost and promoting the yield increase; through the addition of salt-tolerant biological functional substances in the cultivation layer and plastic film mulching, biological enhancement is carried out to realize biological root promotion and inhibit water evaporation and salt upward movement.

[0020] The construction of a suitable rhizosphere micro-region for maize in saline-alkali land provided by the present invention can optimize the physical structure of the soil and evenly supply crop nutrients by increasing carbon, fertilizing, and reducing salt in the saline-alkali soil. At the same time, it can inhibit salt and reduce alkalinity in the rhizosphere micro-region of maize, and can also strengthen the biological functions in the rhizosphere of maize. With the regulation of the maize rhizosphere as the core, through the fertile soil and salt inhibition of the salinized soil, the construction of a suitable rhizosphere micro-region for maize in the salinized cultivated land soil is realized.

[0021] The structure of the suitable rhizosphere micro-region for maize in saline-alkali land can realize the construction of a suitable rhizosphere micro-region for crops in salinized cultivated land, inhibit the accumulation of salt in the rhizosphere micro-region, prevent the salt return on the surface of the saline-alkali soil, and realize the dual improvement of the plow layer structure and fertility of the saline-alkali land. Practices have shown that by using the method for constructing a suitable rhizosphere micro-region for maize in saline-alkali land, the physical and chemical properties of the saline-alkali soil, the soil fertility level, and the maize planting yield can be gradually improved.

[0022] The present invention also provides a high-yield planting technology for maize in saline-alkali land. Through the injection of straw in the maize cultivation in saline-alkali land, the turnover of organic carbon in saline-alkali soil is promoted to realize carbon increase and fertilization; by adding different organic materials, the physical properties of the soil are improved, the organic matter content of the saline-alkali soil and the stability of soil aggregates are enhanced, and at the same time, the microbial activity is promoted to realize the construction of a fertile plow layer in saline-alkali land; through the organic-inorganic composite regulation, the soil structure of saline-alkali land is optimized; by combined seeding and fertilizing, the cultivation cost is saved, the fertilizing and seeding efficiency is improved, the economic benefits are increased, and the growth and development of maize are promoted, jointly realizing the high-yield planting of maize in saline-alkali land. Description of the Drawings

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only the embodiments of the present invention. Without creative efforts, those of ordinary skill in the art can also obtain other drawings according to the provided drawings.

[0024] Figure 1 Schematic diagram of the suitable rhizosphere micro-region for corn in saline-alkali land provided by the present invention;

[0025] Figure 2 Schematic diagram of the rhizosphere micro-region soil structure provided by the present invention;

[0026] In the figure, 1 - suitable rhizosphere micro-region for corn; 2 - straw interlayer; 3 - fertile plough layer; 31 - strip-shaped fertilization area; 4 - cultivation layer; 41 - plastic film. Detailed implementation manners

[0027] The following will clearly and completely describe the technical solutions of the present invention in combination with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0028] The structure of the suitable rhizosphere micro-region 1 for corn in saline-alkali land is as Figure 1 and 2 shown, including a straw interlayer 2, which is arranged underground in the saline-alkali soil layer, a cultivation layer 4 is arranged on the surface of the saline-alkali soil, and a fertile plough layer 3 is arranged between the straw interlayer 2 and the cultivation layer 4;

[0029] The straw interlayer 2 is mainly composed of straw;

[0030] The soil in the fertile plough layer 3 is added with polyurethane-coated controlled-release fertilizer, ordinary chemical fertilizer and organic materials in a strip-shaped fertilization 31;

[0031] The cultivation layer 4 is sprayed with salt-tolerant biological functional substances and is provided with a plastic film 41.

[0032] The straw in the straw layer 2 can increase the soil organic carbon content, promote biological vitality and the development of corn roots. At the same time, it optimizes the physical properties of the soil, enhances aeration and water permeability, blocks salt accumulation and salt upward movement, and inhibits soil surface salinization. In the fertile plough layer 3, polyurethane-coated slow-release fertilizers, ordinary chemical fertilizers and organic materials are added in strip-shaped fertilization 31, which can achieve slow and continuous supply of nutrients in saline-alkali soil, improve soil fertility. Organic materials can accelerate the decomposition of straw, increase the organic matter content, promote the growth and development of corn, and achieve fertile soil for root growth. Strip-shaped fertilization in the fertile plough layer can promote the elongation of corn roots and the uptake of nutrients, improve fertilizer utilization efficiency, reduce fertilizer loss and waste, and reduce the risk of soil environmental pollution. Sowing seeds and fertilizers simultaneously saves time and labor, improves sowing and fertilization efficiency, increases economic benefits while reducing costs, and promotes yield increase.

[0033] In the cultivation layer 4, salt-tolerant biological functional substances are sprayed and the plastic film 41 is covered to achieve biological enhancement, improve the soil environment, promote the development of corn roots, and achieve biological root promotion. Covering the plastic film can inhibit the evaporation and upward movement of surface water, increase temperature and keep warm, and improve the utilization rate of farmland precipitation.

[0034] Through the specific design of the above layers, the soil structure of saline-alkali land is optimized, the soil fertility is improved, at the same time, the salt content is reduced and salt return is prevented, the soil nutrients are stably and continuously released, and high-yield cultivation of corn is achieved.

[0035] The following uses specific examples to illustrate it.

[0036] Example 1

[0037] A method for constructing the rhizosphere micro-region of corn in saline-alkali land includes the following steps:

[0038] (1) After the saline-alkali cultivated land is rotary tilled to a depth of 40 cm with a straw injection type returning machine, straw is injected at a depth of 40 cm in the soil. The injection thickness of the straw is 20 cm, and the length of the straw is 1.5 cm to form a straw layer.

[0039] (2) Polyurethane-coated slow-release fertilizers, ordinary chemical fertilizers and organic materials are applied in strips together with corn seeds by a seed and fertilizer sowing machine. The fertilization depth is 20 cm. The selected corn variety is Ludan 9066. The distance between the fertilizer and the seeds is 10 cm, and the corn sowing depth is 5 cm. The dosage of polyurethane-coated slow-release fertilizer (nutrient content: N-P 2 O 5 -K 2 O: 15-7-4, static water release period is 60 days) is 120 kg·ha -1 , the dosage of ordinary chemical fertilizer is 15 kg N ha of ammonium sulfate -1 , 30 kg N ha of urea -1 , 3 kg P of monoammonium phosphate 2O 5 ha -1 , 3 kg of ammonium polyphosphate in terms of P per ha 2 O 5 ha -1 , 15 kg of superphosphate in terms of P per ha 2 O 5 ha -1 , the application rate of organic materials is 45 t·ha -1 , the organic materials include the compound of cow dung, earthworm dung and furfural residue, forming a fertile plough layer;

[0040] (3) Spraying salt-tolerant biological functional substances on the surface layer of saline-alkali land and covering with plastic film. The application rate of salt-tolerant biological functional substances is 30 L·ha -1 , the dilution ratio is 1:500. The salt-tolerant biological functional substances include the compound of trace elements and amino acids. The spacing of the plastic film is 30 cm, forming a cultivation layer.

[0041] On the 8th day after sowing, the maize seedlings emerge. Open a 3-cm slit in the covered plastic film, take out the maize seedlings outside the film, and cover the slit with soil.

[0042] After implementing the above method for constructing the rhizosphere suitable micro-region of maize in saline-alkali land or the rhizosphere micro-region structure, the maize yield increases from 6140 kg / ha to 6786 kg / ha, with an increase of 11.17%. The soil salt content decreases from 1.81 g / kg to 1.43 g / kg, and the soil salt content decreases by 20.99%. The saline-alkali land soil plays a significant role in salt reduction, nutrient efficiency and high-yield cultivation of maize, and the soil structure of the saline-alkali land is effectively improved.

[0043] Example 2

[0044] A method for constructing the rhizosphere micro-region of maize in saline-alkali land, comprising the following steps:

[0045] (1) After rotary tilling the salinized cultivated land to a depth of 38 cm with a straw injection type subsoiler, inject straw at a depth of 38 cm in the soil. The injection thickness of the straw is 15 cm and the length of the straw is 1 cm, forming a straw interlayer;

[0046] (2) Applying polyurethane-coated controlled-release fertilizer, common chemical fertilizer and organic materials together with maize seeds in a strip shape using a seed-fertilizer drill to the soil. The maize variety is Ludan 9066. The fertilization depth is 18 cm, the distance between the fertilizer and the seeds is 9 cm, and the maize sowing depth is 4 cm. The polyurethane-coated controlled-release fertilizer (nutrient content N-P 2 O 5 -K 2 O: 15-7-4, the static water release period is 60 days) has an application rate of 110 kg·ha -1 , the application rate of common chemical fertilizer is 18 kg of ammonium sulfate in terms of N per ha -1, 33 kg N ha of urea -1 , 4 kg P of monoammonium phosphate 2 O 5 ha -1 , 4 kg P of ammonium polyphosphate 2 O 5 ha -1 , 18 kg P of superphosphate 2 O 5 ha -1 , the application rate of organic materials is 40 t·ha -1 , the organic materials include the compound of cow dung, earthworm manure and furfural residue, forming a fertile plough layer;

[0047] (3) Spray salt-tolerant biological functional substances on the surface layer of saline-alkali land and cover with plastic film. The application rate of salt-tolerant biological functional substances is 40 L·ha -1 , the dilution ratio is 1:800. The salt-tolerant biological functional substances include the compound of trace elements and amino acids. The spacing of the plastic film is 25 cm, forming a cultivation layer.

[0048] Seven days after sowing, the maize emerges. Open a 2.5 cm slit in the covered plastic film, take out the maize seedlings outside the film, and cover the slit with soil.

[0049] After obtaining the rhizosphere suitable micro-region structure by implementing the above-mentioned method for constructing the rhizosphere suitable micro-region of maize in saline-alkali land, the maize yield increases from 6078 kg / ha to 6689 kg / ha, with an increase of 10.05%. The soil salt content decreases from 1.89 g / kg to 1.42 g / kg, and the soil salt content decreases by 24.87%. The saline-alkali land has significant effects in optimizing soil structure, preventing surface soil from returning salt and high-yield cultivation of maize, and effectively reducing the soil salt content of salinized cultivated land.

[0050] Example 3

[0051] A method for constructing the rhizosphere micro-region of maize in saline-alkali land, comprising the following steps:

[0052] (1) After rotary tilling the salinized cultivated land to a depth of 35 cm with a straw injection type returning machine, inject straw at a depth of 35 cm in the soil. The injection thickness of the straw is 10 cm and the straw length is 2 cm, forming a straw interlayer;

[0053] (2) Apply polyurethane coated controlled release fertilizer, ordinary chemical fertilizer and organic materials together with maize seeds in a strip shape using a seed fertilizer broadcaster. The maize variety is Ludan 9066. The fertilizer input depth is 15 cm, the distance between the fertilizer and the seeds is 8 cm, and the maize sowing depth is 3 cm. The polyurethane coated controlled release fertilizer (nutrient content is N-P 2 O 5 -K 2O: 15 - 7 - 4, with a static water release period of 60 days), the dosage is 100 kg·ha -1 , the dosage of ordinary chemical fertilizer is 20 kg of ammonium sulfate N ha -1 , 35 kg of urea N ha -1 , 5 kg of monoammonium phosphate P 2 O 5 ha -1 , 5 kg of ammonium polyphosphate P 2 O 5 ha -1 , 20 kg of superphosphate P 2 O 5 ha -1 , the dosage of organic materials is 35 t·ha -1 , the organic materials include the compound of cow dung, earthworm manure and furfural residue, forming a fertile plough layer;

[0054] (3) Spray salt - tolerant biological functional substances on the surface layer of saline - alkali land and cover with plastic film. The dosage of salt - tolerant biological functional substances is 50 L·ha -1 , the dilution ratio is 1:1000. The salt - tolerant biological functional substances include the compound of trace elements and amino acids. The spacing of the plastic film is 20 cm, forming a cultivation layer.

[0055] Six days after sowing, the corn seeds germinate. Open a 2 - cm slit in the covered plastic film, take out the corn seedlings outside the film, and cover the slit with soil.

[0056] After obtaining the rhizosphere suitable micro - domain structure by implementing the above - mentioned method for constructing the rhizosphere suitable micro - domain of saline - alkali land corn, the corn yield increases from 6138 kg / ha to 6798 kg / ha, with an increase of 10.75%. The soil salt content decreases from 1.74 g / kg to 1.43 g / kg, and the soil salt content decreases by 17.82%.

[0057] In summary, the advantages of the method for constructing the rhizosphere suitable micro - domain of saline - alkali cultivated land corn or the rhizosphere suitable micro - domain structure enable it to have wide adaptability to saline - alkali soil corn cultivation land, with low cost, easy operation and strong usability. It can effectively improve the soil structure of saline - alkali cultivated land, promote the construction of the rhizosphere suitable micro - domain of corn, increase the yield of saline - alkali cultivated land corn, and has broad application prospects in the saline - alkali land corn cultivation system.

[0058] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other. The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can 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 these embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for constructing a suitable micro-domain for corn rhizosphere in saline-alkali land, characterized in that: The following steps are involved: (1) After rotary tillage with a straw injection machine in salinized farmland, straw is injected deep into the soil to form a straw barrier; (2) applying polyurethane coated slow-release fertilizer, chemical fertilizer, organic materials and corn seeds into the soil in strips using a seed and fertilizer planter to form a fertile tillage layer; (3) Spray salt-tolerant biological functional substances on the surface of saline-alkali soil and then cover it with a film to form a cultivation layer.

2. The method for constructing a suitable micro-domain for corn rhizosphere in saline-alkali land according to claim 1, characterized in that: In step (1), the rotary tillage depth is 30-40 cm, the straw injection depth is 30-40 cm, the straw barrier thickness is 10-20 cm, and the straw length is 1-2 cm.

3. The method for constructing a suitable micro-domain for corn rhizosphere in saline-alkali land according to claim 1, characterized in that: In step (2), the fertilizer is applied at a depth of 15-20 cm, the sowing depth is 3-5 cm, and the distance between the fertilizer and the seeds is 8-10 cm.

4. The method for constructing a suitable micro-domain for corn rhizosphere in saline-alkali land according to claim 1, characterized in that: The nutrient content of the polyurethane coated slow-release fertilizer is N-P2O5-K2O: 15-7-4, the static water release period of the polyurethane coated slow-release fertilizer is 60 days, and the application amount of the polyurethane coated slow-release fertilizer is 100-120 kg·ha -1 .

5. The method for constructing a suitable micro-domain for corn rhizosphere in saline-alkali land according to claim 1, characterized in that: The organic material includes one or more of earthworm manure, cow dung, biochar, humic acid or furfural residue, and the application amount of the organic material is 35-45 t·ha -1 .

6. The method for constructing a suitable micro-domain for corn rhizosphere in saline-alkali land according to claim 1, characterized in that: The fertilizer and application amount in step (2) include ammonium sulfate 15-20kg N ha -1 , urea 30-35 kg N ha -1 , monoammonium phosphate 3-5kgP2O5 ha -1 , ammonium polyphosphate 3-5kg P2O5 ha -1 , superphosphate 15-20kg P2O5 ha -1 .

7. The method for constructing a suitable micro-domain for corn rhizosphere in saline-alkali land according to claim 1, characterized in that: The salt-tolerant biological functional substance in step (3) includes one or more of polypeptide trace element water-soluble fertilizer, seaweed polypeptide, amino acid, seaweed polysaccharide or agricultural bacteriophage, and the dosage is 30-50 L·ha -1 When using, dilute it with water at a ratio of 1:500-1:1000.

8. The method for constructing a suitable micro-domain for corn rhizosphere in saline-alkali land according to claim 1, characterized in that: In step (3), the film is covered with ground film or liquid ground film, and the covering distance is 10-20cm.

9. The method for constructing a suitable micro-domain for corn rhizosphere in saline-alkali land according to claim 1, characterized in that: The method also includes step (4): when the corn seedlings emerge 5-8 days after sowing, a 2-3 cm hole is opened in the ground film, the corn seedlings are taken out, and the hole is covered with soil.

10. Use of the method according to any one of claims 1 to 9 in high-yield corn planting.

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