A biological slow-release fertilizer for corn planting on sloping land and a preparation method thereof

Abstract

The application provides a kind of biological slow-release fertilizer for corn planting on slope and a preparation method thereof, and relates to the technical field of corn planting.The fertilizer is composed of straw fermentation material, humic acid, diatomite, modified starch material, biochar, puffed vermiculite, sodium alginate, magnesium sulfate, potassium dihydrogen phosphate, urea, trisodium ethylenediamine disuccinate and propyl gallate;and the straw fermentation material is obtained by alkali treatment after crushing straw, inoculation of aspergillus oryzae fermentation, sterilization, and then inoculation of bacillus subtilis fermentation, drying;the modified starch material is obtained by mixing semi-gelatinized starch material and completely gelatinized starch material.The application overcomes the shortcomings of the prior art, effectively promotes early maturity of corn planting on slope by adjusting and improving the fertilizer, prevents water and soil loss during planting, and achieves the effect of high-yield corn planting.

Description

Technical Field

[0001] This invention relates to the field of corn planting technology, specifically to a bio-slow-release fertilizer for corn planting on slopes and its preparation method. Background Technology

[0002] Corn is one of the world's most important food crops. Corn cultivation usually requires tilling the land, especially when planted on slopes, where soil loosening reduces surface stability. Without cover (such as straw, mulch film) or vegetation protection, rainwater erosion can easily lead to the loss of topsoil.

[0003] Of Yunnan Province's nearly 80 million mu (approximately 5.3 million hectares) of arable land, 75% is sloping land, with half of these slopes exceeding 6°. This area is also the main corn-growing region in Yunnan. Yunnan is located in a typical monsoon climate zone, with an annual rainfall of approximately 1100 mm. Of this, 85-90% of the rainfall is concentrated between May and October; 60% is concentrated between June and August; and less than 10-15% is received from November to April of the following year. Due to this extremely uneven rainfall distribution, drought in winter and spring and soil erosion from summer torrential rains are prominent problems. This has led to a dilemma in corn production: "early planting results in no corn, late planting results in no corn ripening."

[0004] Current methods mostly involve adjusting the corn planting time, postponing the original mid-to-late April planting to mid-to-late May. Although this method improves the corn emergence rate, it still presents problems such as soil erosion and difficulties in corn ripening and harvesting. First, early heavy rains often occur during the period from corn sowing to crop canopy closure, and the loosening of the soil during this period exacerbates soil erosion. Second, the extended harvest time means that corn will be harvested in October, but the sharp drop in temperature in September makes it difficult for corn to ripen, resulting in reduced yield. Third, the corn harvesting period in October is often accompanied by continuous rainy weather with "rotten soil and yellowing leaves," making harvesting difficult.

[0005] Therefore, ensuring normal corn planting while avoiding the adverse weather conditions in September and October, and thus guaranteeing corn yield, is an important research direction at this stage. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a biological slow-release fertilizer for corn planting on slopes and its preparation method. By adjusting and improving the fertilizer, it effectively promotes the early maturity of corn planted on slopes, achieving the effect of high-yield corn planting.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A bio-slow-release fertilizer for corn cultivation on slopes, comprising the following components by weight: 15-20 parts fermented straw, 4-6 parts humic acid, 6-8 parts diatomaceous earth, 4-6 parts modified starch, 4-8 parts biochar, 4-6 parts expanded vermiculite, 2-4 parts sodium alginate, 2-4 parts magnesium sulfate, 2-4 parts potassium dihydrogen phosphate, 4-6 parts urea, 0.5-1.2 parts trisodium ethylenediaminedisuccinate, and 0.1-0.2 parts propyl gallate. The fermented straw is prepared by crushing straw, treating it with alkali, inoculating it with Aspergillus oryzae for fermentation, sterilizing it, and then further inoculating it with Bacillus subtilis for fermentation and drying it. The modified starch is obtained by mixing semi-gelatinized starch and fully gelatinized starch at a mass ratio of 3-5:1.

[0009] Preferably, the specific preparation method of the fermented straw material includes the following steps:

[0010] S1-1. After drying the straw, crush it to a particle size of 1-3 cm to obtain straw fragments. Soak the straw fragments in an alkaline solution with a pH of 10-11 for 15-20 minutes, then adjust the pH to 6.5-6.8. Inoculate with 0.4%-0.6% of Aspergillus oryzae by weight of the total straw fragments and ferment for 2-4 days to obtain the preliminary fermented material.

[0011] S1-2. After sterilizing the above-mentioned preliminary fermented material, sterilized material is obtained for later use;

[0012] S1-3. Inoculate the sterilized material with 0.2%-0.3% of the total mass of straw shreds as Bacillus subtilis, continue fermentation for 1-3 days, then dry and pulverize to obtain fermented straw material.

[0013] Preferably, the sterilization method in step S1-2 is high-pressure steam sterilization at 121°C and 0.2 MPa for 20 minutes.

[0014] Preferably, the drying and pulverizing method in steps S1-3 is to dry with hot air at 35-45℃ and pulverize through an 80-mesh sieve.

[0015] Preferably, the preparation method of the modified starch material includes the following steps:

[0016] S2-1. Mix corn starch with 3-5 times its volume of water and treat at 65℃ for 30-40 minutes, then freeze dry to obtain semi-gelatinized starch.

[0017] S2-2. Mix corn starch with 3-5 times its volume of water and treat at 75℃ for 30-40 minutes, then freeze dry to obtain fully gelatinized starch.

[0018] S2-3. Mix semi-gelatinized starch and fully gelatinized starch evenly at a mass ratio of 3-5:1 to obtain modified starch material.

[0019] The preparation method of the above-mentioned slow-release fertilizer includes the following steps:

[0020] (1) Add the modified starch to 15-20 times the amount of water and stir thoroughly to obtain starch slurry for later use;

[0021] (2) Add the fermented straw and diatomaceous earth to the starch slurry and mix thoroughly to obtain the first mixture;

[0022] (3) Mix sodium alginate, magnesium sulfate, potassium dihydrogen phosphate, urea, trisodium ethylenediamine disuccinate and propyl gallate, add 5-8 times the volume of water, stir thoroughly, then add biochar and stir in a water bath to obtain the second mixture.

[0023] (4) Add the expanded vermiculite and the second mixture to the first mixture, pressurize to 0.1-0.2 MPa, continue stirring for 30-40 minutes, then dry until the moisture content is ≤50%, then extrude and granulate and dry to obtain slow-release fertilizer.

[0024] Preferably, in step (3), the temperature of the water bath stirring is 60-70℃, the stirring time is 15-30min, and the stirring speed is 120-800r / min.

[0025] Preferably, the stirring speed in step (4) is 80-200 r / min.

[0026] Preferably, the drying temperature in step (4) is 35-45℃.

[0027] This invention provides a bio-slow-release fertilizer for corn planting on slopes and its preparation method, which has the following advantages compared with the prior art:

[0028] This invention uses a mixture of fermented straw material fermented with Aspergillus oryzae and Bacillus subtilis in a specific manner, modified starch material, biochar, trisodium ethylenediamine disuccinate, propyl gallate, and other raw materials to formulate a bio-slow-release fertilizer. This fertilizer effectively improves soil water retention capacity, promotes rapid corn growth, reduces water and soil loss as well as nitrogen and phosphorus nutrient loss, and effectively avoids the impact of a sharp drop in temperature in September on corn maturity, thus achieving a bumper corn yield and increasing the economic benefits of corn planting. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the planting experimental area after land preparation in the planting experiment of this invention;

[0030] Figure 2 This is a schematic diagram of the corn seedlings after thinning in the planting experiment of this invention;

[0031] Figure 3This is a schematic diagram of the corn harvested in the planting area of ​​this invention, where from left to right, the diagrams represent planting areas 1 to 5 (each planting area has three corn plants);

[0032] Figure 4 This is a schematic diagram of the corn harvested in the planting area of ​​the present invention, wherein from left to right, the diagrams are of corn in planting areas 6 to 10 (three corns in each planting area). Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] The Aspergillus oryzae used below were Aspergillus oryzae SHBCC D81898 CGMCC3.951 with a viable count of 2 billion CFU / g, purchased from Wuhan Huanna Biotechnology Co., Ltd.; Bacillus subtilis was purchased from Chaoyang Huaxing Bioengineering Co., Ltd. with a viable count of 100 billion CFU / g.

[0035] The straw material used below is a mixture of equal weights of corn straw and soybean straw.

[0036] Semi-gelatinized starch is obtained by mixing corn starch with 4 times its volume of water, treating it at 65°C for 35 minutes, and then freeze-drying it.

[0037] Fully gelatinized starch is obtained by mixing corn starch with 4 times its volume of water, treating it at 70°C for 35 minutes, and then freeze-drying it.

[0038] Biochar is coconut shell charcoal with a particle size of 0.5-1mm.

[0039] Example 1:

[0040] Raw material processing:

[0041] 1. Preparation of Straw Fermentation Material-1:

[0042] (1) After drying the straw, crush it to a particle size of 1-3 cm to obtain straw fragments. Soak the straw fragments in a sodium hydroxide solution with a pH of 10.5 for 20 min, then adjust the pH to 6.8, inoculate 0.6% of the total mass of straw fragments with Aspergillus oryzae, and ferment for 3 days to obtain preliminary fermented material.

[0043] (2) Sterilize the above-mentioned preliminary fermented material with high-pressure steam at 121℃ and 0.2Mpa for 20 minutes to obtain sterilized material for later use;

[0044] (3) Inoculate the sterilized material with 0.2% of the total mass of straw fragments of Bacillus subtilis, continue fermentation treatment for 2 days, then dry with hot air at 40℃ and crush through an 80-mesh sieve to obtain straw fermentation material-1.

[0045] 2. Preparation of Straw Fermentation Material-2:

[0046] (1) After drying the straw, crush it to a particle size of 1-3 cm to obtain straw fragments. Soak the straw fragments in a sodium hydroxide solution with a pH of 10.5 for 20 min, then adjust the pH to 6.8, inoculate 0.6% of the total mass of straw fragments with Aspergillus oryzae, and ferment for 3 days to obtain preliminary fermented material.

[0047] (2) Inoculate the preliminary fermented material with 0.2% of the total mass of straw fragments of Bacillus subtilis, continue fermentation treatment for 2 days, then dry with hot air at 40℃ and crush through an 80-mesh sieve to obtain straw fermented material-2.

[0048] 3. Preparation of Straw Fermentation Material-3:

[0049] After drying, the straw is crushed to a particle size of 1-3 cm to obtain straw fragments. The straw fragments are then soaked in a sodium hydroxide solution with a pH of 10.5 for 20 minutes, and the pH is adjusted to 7.0. 0.2% of the total mass of the straw fragments is inoculated with Bacillus subtilis and fermented for 2 days. After that, the straw is dried with hot air at 40℃ and crushed through an 80-mesh sieve to obtain straw fermentation material-3.

[0050] 4. Preparation of Straw Fermentation Material-4:

[0051] (1) After drying the straw, crush it to a particle size of 1-3 cm to obtain straw fragments. Soak the straw fragments in clean water for 20 minutes, then adjust the pH to 6.8, inoculate 0.6% of the total mass of straw fragments with Aspergillus oryzae, and ferment for 3 days to obtain preliminary fermented material;

[0052] (2) Sterilize the above-mentioned preliminary fermented material with high-pressure steam at 121℃ and 0.2Mpa for 20 minutes to obtain sterilized material for later use;

[0053] (3) Inoculate the sterilized material with 0.2% of the total mass of straw fragments of Bacillus subtilis, continue fermentation treatment for 2 days, then dry with hot air at 40℃ and crush through an 80-mesh sieve to obtain straw fermentation material-1.

[0054] 5. Prepare different modified starch materials according to the mass ratios in Table 1 below:

[0055]

[0056] Example 2:

[0057] Preparation of slow-release fertilizers:

[0058] (1) Prepare the following materials according to the following weight parts: 18 parts of fermented straw, 5 parts of humic acid, 7 parts of diatomaceous earth, 5 parts of modified starch, 6 parts of biochar, 5 parts of expanded vermiculite, 3 parts of sodium alginate, 3 parts of magnesium sulfate, 3 parts of potassium dihydrogen phosphate, 5 parts of urea, 0.9 parts of trisodium ethylenediamine disuccinate, and 0.15 parts of propyl gallate;

[0059] (2) Add the modified starch to 18 times its volume of water and stir thoroughly to obtain starch slurry for later use;

[0060] (3) Add the fermented straw and diatomaceous earth to the starch slurry and mix thoroughly to obtain the first mixture;

[0061] (4) Sodium alginate, magnesium sulfate, potassium dihydrogen phosphate, urea, trisodium ethylenediamine disuccinate and propyl gallate are mixed and added to 6 times the volume of water. The mixture is stirred thoroughly and then biochar is added and stirred thoroughly at 65°C for 25 minutes to obtain the second mixture.

[0062] (5) Add the expanded vermiculite and the second mixture to the first mixture, pressurize to 0.1 MPa, continue stirring for 40 minutes, then dry until the moisture content is ≤50%, then extrude and granulate and dry to obtain slow-release fertilizer.

[0063] Following the above preparation method, different slow-release fertilizers were prepared by selecting different fermented straw materials and modified starch materials according to Table 2 below:

[0064]

[0065] Comparative Example 1:

[0066] Referring to the preparation method and formula of SRF-1 slow-release fertilizer in Example 2 above, only the addition of trisodium ethylenediamine disuccinate was omitted to obtain SRF-8 slow-release fertilizer.

[0067] Comparative Example 2:

[0068] Referring to the preparation method and formula of SRF-1 slow-release fertilizer in Example 2 above, only the addition of propyl gallate was omitted to obtain SRF-9 slow-release fertilizer.

[0069] Planting experiment:

[0070] A sloping area (8° slope) in Zhanyi District, Qujing City, Yunnan Province was selected as the planting experimental area. Deep plowing and sun-drying were carried out in late March, and the land was leveled and compacted before sowing (e.g., ...). Figure 1 );

[0071] Planting with wide and narrow rows, with a wide row spacing of 90cm and a narrow row spacing of 40cm-50cm; create ridges 1.2 meters apart along the contour lines, with a ridge width of 70cm-80cm and a ridge height of 15cm;

[0072] The experimental area was divided into 10 planting zones (each planting zone was further divided into 3 planting blocks as replicates). Multiple planting holes with a row spacing of 30-40 cm were dug on the soil surface in each planting zone. Slow-release fertilizer (250g per hole) was applied to each planting hole, covered with a thin layer of soil, and then covered with a plastic film. After breaking the film in the center of each planting hole, 2-3 corn seeds were sown in each hole and covered with soil. Subsequently, a 75% acetochlor emulsion diluted 300 times with water was sprayed. When the corn reached 5 leaves, thinning began to ensure one plant per hole (e.g., ...). Figure 2 ).

[0073] The selection of slow-release fertilizers for each planting area is shown in Table 3 below:

[0074]

[0075] Starting in August, check the maturity of corn in each planting area (maturity is indicated by the outer corn husks turning white and loosening), and harvest in a timely manner (compare corn from different planting areas at harvest time). Figure 3 and Figure 4 As shown in Table 4, the corn in the planting area is considered fully mature when the total number of corn ears harvested reaches 80%. The time of full maturity is recorded, and the corn yield and thousand-kernel weight are calculated.

[0076]

[0077] In conclusion, choosing slow-release fertilizers SRF-1 and SRF-6 for planting can effectively promote early maturity of corn and achieve the goal of high yield.

[0078] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A bio-slow-release fertilizer for corn cultivation on slopes, characterized in that, The fertilizer is composed of the following components by weight: 15-20 parts fermented straw, 4-6 parts humic acid, 6-8 parts diatomaceous earth, 4-6 parts modified starch, 4-8 parts biochar, 4-6 parts expanded vermiculite, 2-4 parts sodium alginate, 2-4 parts magnesium sulfate, 2-4 parts potassium dihydrogen phosphate, 4-6 parts urea, 0.5-1.2 parts trisodium ethylenediamine disuccinate, and 0.1-0.2 parts propyl gallate. The straw fermentation material is prepared by crushing straw, treating it with alkali, inoculating it with Aspergillus oryzae for fermentation, sterilizing it, then inoculating it with Bacillus subtilis for fermentation and drying it. The modified starch material is obtained by mixing semi-gelatinized starch material and fully gelatinized starch material at a mass ratio of 3-5:

1.

2. The slow-release fertilizer according to claim 1, characterized in that, The specific preparation method of the fermented straw material includes the following steps: S1-1. After drying the straw, crush it to a particle size of 1-3 cm to obtain straw fragments. Soak the straw fragments in an alkaline solution with a pH of 10-11 for 15-20 minutes, then adjust the pH to 6.5-6.

8. Inoculate with 0.4%-0.6% of Aspergillus oryzae by weight of the total straw fragments and ferment for 2-4 days to obtain the preliminary fermented material. S1-2. After sterilizing the above-mentioned preliminary fermented material, sterilized material is obtained for later use; S1-3. Inoculate the sterilized material with 0.2%-0.3% of the total mass of straw shreds as Bacillus subtilis, continue fermentation for 1-3 days, then dry and pulverize to obtain fermented straw material.

3. The slow-release fertilizer according to claim 2, characterized in that: The sterilization method in step S1-2 is high-pressure steam sterilization at 121℃ and 0.2MPa for 20 minutes.

4. The slow-release fertilizer according to claim 2, characterized in that: In steps S1-3, the drying and pulverizing method is to dry with hot air at 35-45℃ and pulverize through an 80-mesh sieve.

5. The slow-release fertilizer according to claim 1, characterized in that, The preparation method of the modified starch material includes the following steps: S2-1. Mix corn starch with 3-5 times its volume of water and treat at 65℃ for 30-40 minutes, then freeze dry to obtain semi-gelatinized starch. S2-2. Mix corn starch with 3-5 times its volume of water and treat at 75℃ for 30-40 minutes, then freeze dry to obtain fully gelatinized starch. S2-3. Mix semi-gelatinized starch and fully gelatinized starch evenly at a mass ratio of 3-5:1 to obtain modified starch material.

6. A method for preparing a slow-release fertilizer as described in any one of claims 1-3, characterized in that, The method for preparing the slow-release fertilizer includes the following steps: (1) Add the modified starch to 15-20 times the amount of water and stir thoroughly to obtain starch slurry for later use; (2) Add the fermented straw and diatomaceous earth to the starch slurry and mix thoroughly to obtain the first mixture; (3) Sodium alginate, magnesium sulfate, potassium dihydrogen phosphate, urea, trisodium ethylenediamine disuccinate and propyl gallate are mixed and added to 5-8 times the volume of water. The mixture is stirred thoroughly and then biochar is added. The mixture is stirred in a water bath to obtain the second mixture. (4) Add the expanded vermiculite and the second mixture to the first mixture, pressurize to 0.1-0.2 MPa, continue stirring for 30-40 minutes, then dry until the moisture content is ≤50%, then extrude and granulate and dry to obtain slow-release fertilizer.

7. The method according to claim 6, characterized in that: In step (3), the water bath stirring temperature is 60-70℃, the stirring time is 15-30min, and the stirring speed is 120-800r / min.

8. The method according to claim 6, characterized in that: In step (4), the stirring speed is 80-200 r / min.

9. The method according to claim 6, characterized in that: The drying temperature in step (4) is 35-45℃.

Images