Rice seedling raising substrate sheet, preparation method thereof and seedling raising method

Abstract

The invention provides a rice seedling raising substrate sheet and a preparation method thereof and a seedling raising method, and belongs to the technical field of rice seedling raising, and the preparation method comprises the following steps: mixing decomposed straw, an adhesive and biochar, spraying water to adjust the water content to be 50-60%, and performing hot pressing at the temperature of 120-150 DEG C to form a latticed separator; thoroughly decomposed straw, thoroughly decomposed livestock and poultry manure and water are mixed and stirred and then ground into slurry, the pH is adjusted to 6.0-6.5, and substrate slurry is obtained; and filling meshes of the latticed separator with the matrix slurry, carrying out vacuum suction filtration molding, and drying to obtain the rice seedling raising matrix sheet. The matrix slurry in the rice seedling raising matrix sheet adopts an acid regulation and nutrient controlled release technology, a stable and coordinated growth medium with a water, gas and fertilizer structure can be provided for seedlings, meanwhile, root systems of the seedlings are orderly separated by the latticed separators in the growth process, the root systems of the seedlings are coiled in meshes, the root system activity is high, and the quality of the seedlings is good.

Description

Technical Field

[0001] This invention relates to the field of rice seedling cultivation technology, specifically to a rice seedling cultivation substrate sheet, its preparation method, and seedling cultivation method. Background Technology

[0002] The quality of rice seedlings directly determines the yield and profitability of field crops. The most prominent problems with traditional nutrient soil seedling raising methods are: first, difficulty in obtaining soil for seedling raising, as dryland soil often contains herbicide residues, resulting in poor soil quality and poor seedling quality; second, the large amount of soil used damages the topsoil, leading to soil erosion and ecological damage; third, the technical steps of soil collection, drying, crushing, sieving, and mixing with fertilizers and pesticides are cumbersome, labor-intensive, time-consuming, and time-consuming; and fourth, poor soil quality results in thin, weak seedlings, making them susceptible to diseases and pesticide damage, severely restricting rice yield increases. Seedlings raised using pre-formed substrate sheets have high root aeration, good root development, strong root vitality, and uniform seedling density in the field, greatly reducing the pressure of later replanting.

[0003] However, the root systems of seedlings raised on pre-formed substrate sheets are too tightly intertwined, and the tearing action of the seedling needles during transplanting causes severe damage to the roots. These factors result in a prolonged recovery period for the seedlings after transplanting, leading to a longer rice growth cycle. Excessive direct return of straw to the field over a long period can easily lead to crop diseases and pests, causing a significant drop in yield and posing a major threat to grain production. Furthermore, poor treatment of livestock manure can cause significant pollution to the surrounding environment. Therefore, it is necessary to accelerate the research and development of pre-formed seedling substrate sheets made primarily from livestock manure and crop straw, to achieve the rational, large-scale recycling of these materials in industrial settings. Summary of the Invention

[0004] In view of the technical problems existing in the background art, this application provides a rice seedling substrate sheet and its preparation method and seedling raising method, aiming to solve the technical problem that the seedling roots are too tightly tangled in the existing substrate sheet, and the roots are easily damaged during transplanting.

[0005] In a first aspect, embodiments of this application provide a method for preparing rice seedling substrate sheets, comprising the following steps: S1. After mixing the decomposed straw, binder and biochar, spray water to adjust the moisture content to 50%~60%, and hot press it into a grid-like separator at a temperature of 120~150℃; the mass ratio of decomposed straw, binder and biochar is (8~15):(3~4):(5~8); S2. Mix and stir the decomposed straw, decomposed livestock and poultry manure and water, then grind them into a slurry and adjust the pH to 6.0~6.5 to obtain the matrix slurry; the mass ratio of decomposed straw, decomposed livestock and poultry manure and water is (13~17):(10~14):100. S3. Fill the mesh of the grid-like separator with the substrate slurry, vacuum filter and form, and dry to obtain rice seedling substrate sheet.

[0006] Secondly, this application provides a rice seedling substrate sheet, which is prepared using the above method.

[0007] Thirdly, embodiments of this application provide a seedling raising method, comprising the following steps: (1) Dry the rice seeds for 1-2 days, remove the shriveled grains, soak them in clean water for 24 hours until they break open and show white, and then coat them with seed coating agent to obtain pretreated seeds; (2) Place the rice seedling substrate sheet into the seedling tray and press it firmly against the seedling tray; (3) Sow the pretreated seeds on the rice seedling substrate, cover with a layer of seed-covering soil 0.3~0.5cm thick, then spray water until the seed-covering soil and rice seedling substrate are moist and the bottom of the seedling tray is no longer dripping water, and then cover the seedling tray with non-woven fabric. (4) The ambient temperature before rice seedling emergence should be controlled at around 30℃, the night temperature after rice seedling emergence should be controlled at above 15℃, and the daytime temperature after rice seedling emergence should be controlled at 20~30℃; before the seedling height reaches 2.5cm, the seedling tray should be kept moist; when the seedling growth is weak, apply quick-acting fertilizer when the seedling is in the two-leaf-one-heart stage; when the seedling is in the one-leaf-one-heart stage, mix and spray foliar fertilizer and fungicide, and remove miscellaneous plants and weeds; (5) Apply insecticide when the seedlings have 1.5 leaves, and apply a transplanting agent 2-3 days before transplanting; (6) Roll up the seedlings of the appropriate age and then transport and transplant them.

[0008] The advantages of this application, which differ from existing technical solutions, include: 1. The rice seedling substrate sheet of this invention utilizes acidification (pH controlled at 5.5-6) ​​and nutrient controlled-release technology to provide seedlings with a stable and coordinated growth medium of water, air, and fertilizer. Simultaneously, the seedling roots are orderly separated by a grid-like partition during growth, with the roots coiled within the mesh openings, resulting in strong root vitality and high-quality seedlings. During transplanting using a rice transplanter, the transplanter's needles separate the seedlings from the substrate sheet along the grid partitions without tearing the seedling roots. This allows the substrate sheet and some of the partition material within the mesh to be carried into the paddy field, maintaining a stable root microenvironment. This facilitates rapid adaptation of the seedlings to the new environment, significantly shortening the seedling establishment period and thus the seedling growth cycle, ultimately increasing yield and efficiency.

[0009] 2. A grid-like separator is prepared using decomposed straw, adhesive, and biochar. Biochar is filled into the pores of the decomposed straw, and the separator is bonded together with the adhesive. The separator is then hot-pressed to form a dense grid-like separator with strong physical barrier properties. This prevents root penetration, allowing rice seedlings in different meshes to have their own independent growth space. Roots are less likely to become entangled, making transplanting easier and eliminating the need for acclimatization. This also promotes the formation of low-lying tillers in rice.

[0010] 3. By using the rice seedling substrate sheet of this invention, the heavy processes of digging, drying, crushing, sieving, mixing and acidifying soil in the traditional seedbed preparation process are no longer required. This saves both labor and the investment in mechanical equipment. Users can buy and use it immediately. It is a "materialized technology" that saves labor, effort and worry.

[0011] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Detailed Implementation

[0012] The embodiments of the technical solution of this application are described in detail below. The following embodiments are only used to illustrate the technical solution of this application more clearly, and are therefore only examples, and should not be used to limit the scope of protection of this application.

[0013] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion.

[0014] The roots of seedlings raised on pre-formed substrate sheets are too tightly intertwined, and the seedling needles tearing during transplanting by the rice transplanter cause serious damage to the roots. These factors lead to a period of recovery for the seedlings after transplanting, resulting in a longer rice growth cycle.

[0015] To address the technical problem of overly tightly coiled seedling roots in the substrate sheet, which easily damages the roots during transplanting, this application provides a rice seedling substrate sheet, its preparation method, and a seedling raising method. In this method, by setting up grid-like separators, the seedling roots are orderly separated by the grid-like separators during the growth process. The seedling roots are coiled within the mesh, resulting in strong root vitality and good seedling quality.

[0016] In a first aspect, embodiments of this application provide a method for preparing rice seedling substrate sheets, comprising the following steps: S1. After mixing the decomposed straw, binder and biochar, spray water to adjust the moisture content to 50%~60%, and hot press it into a grid-like separator at a temperature of 120~150℃; the mass ratio of the decomposed straw, binder and biochar is (8~15):(3~4):(5~8); S2. Mix and stir the decomposed straw, decomposed livestock and poultry manure and water, then grind them into a slurry and adjust the pH to 6.0~6.5 to obtain the matrix slurry; the mass ratio of the decomposed straw, decomposed livestock and poultry manure and water is (13~17):(10~14):100. S3. The substrate slurry is filled into the mesh of the grid-like separator, vacuum filtered and formed, and then dried to obtain rice seedling substrate sheets.

[0017] In the technical solution of this application embodiment, biochar is filled into the pores of decomposed straw and bonded together with an adhesive. By pressing, it forms a tightly packed grid-like separator, which has a strong physical barrier effect, preventing root penetration and allowing rice seedlings in different grids to have their own independent growth space. The roots are not easily entangled, making transplanting easier and eliminating the need for seedling establishment. This is conducive to the formation of low-level tillers in rice.

[0018] The mass ratio of the adhesive is not limited to the range mentioned above. By selecting an adhesive within this mass ratio range, the connection between the decomposed straw and biochar can be made tighter, enhancing the mechanical properties of the separator and preventing deformation of the separator when filling the matrix slurry.

[0019] The mass ratio of biochar includes, but is not limited to, the range mentioned above. Using biochar within this mass ratio range can improve the compactness of the separators and reduce the root penetration ability. At the same time, during the biochar transplanting process, the biochar is peeled off by the rice transplanter and mixed into the soil of the paddy field, which can promote the growth and development of rice.

[0020] Furthermore, in some embodiments, the method for preparing decomposed straw includes the following steps: The straw is crushed to a particle size of 4-8 mm, and straw composting agent and nitrogen source are added. Water is added to adjust the moisture content to 65%-70% to obtain the first premix. The mass ratio of straw, straw composting agent and nitrogen source in the first premix is ​​1000:(4-8):(10-15). The first premixed material is subjected to closed aerobic fermentation for 10-15 days to obtain decomposed straw.

[0021] Furthermore, in some embodiments, the straw includes at least one of rice straw and corn straw. Furthermore, in some embodiments, the nitrogen source includes urea.

[0022] Furthermore, in some embodiments, the method for preparing decomposed livestock and poultry manure includes the following steps: Animal manure and straw are mixed in a weight ratio of 7:3. Straw composting agent is evenly sprinkled in during the mixing process. The moisture content of the mixed material is adjusted to 55%~60% to obtain a second premix. The mass ratio of straw, animal manure and straw composting agent in the second premix is ​​(25~30):(65~70):(0.04~0.08). The second premixed material is fed into the integrated intelligent aerobic fermentation chamber and stacked according to the chamber specifications to form a fermentation pile. It is advisable to fill the chamber. A blower is used to ventilate and aerate from the bottom of the fermentation tank every 2 hours. The fermentation temperature is maintained at 60~65℃ for uniform aerobic fermentation. The fermentation cycle is 12~15 days, and the primary fermented material is obtained. The primary fermented material is transported to the aging workshop for stacking to form a secondary fermentation pile. The secondary fermentation pile is turned over every 7 to 10 days, and the fermentation cycle is 90 to 120 days, resulting in well-rotted livestock and poultry manure that is yellowish-brown or grayish-brown.

[0023] Furthermore, in some embodiments, the adhesive is made from oxidized starch, citric acid and glycerol in a mass ratio of 100:(10~30):(5~15).

[0024] In the technical solution of this application embodiment, oxidized starch, after gelatinization, becomes sticky and can bind fibers, making it easy to press decomposed straw and biochar into shape. Hot pressing can promote further gelation of starch and enhance adhesion. Adding glycerol can act as a plasticizer, inserting between starch molecular chains, weakening intermolecular forces, making the formed film soft and tough, preventing brittleness, and thus giving the made separator a certain degree of flexibility, making it easy to roll up when transporting seedlings and transplanting rice. At the same time, oxidized starch and glycerol are used as adhesives, which are widely available, low in cost, and biodegradable.

[0025] Citric acid and oxidized starch can undergo esterification and cross-linking reaction, giving the adhesive good water resistance. This allows the separator to maintain its shape and strength even after being exposed to water, preventing it from gelatinizing and collapsing. As a result, it plays a good role in inhibiting root spread during the seedling raising process.

[0026] Furthermore, in some embodiments, the biochar is rice husk biochar.

[0027] Secondly, embodiments of this application provide a rice seedling substrate sheet, which is prepared using the above-described method.

[0028] Furthermore, in some embodiments, the rice seedling substrate sheet includes a grid-like separator and a substrate material filled within the mesh openings of the grid-like separator; The rice seedling substrate sheet is 570mm long, 270mm wide, and 8-12mm thick. The grid-like separator includes transverse and longitudinal spacers, with a thickness of 2-3 mm and a height of 8-12 mm; the mesh size of the grid-like separator is 15-20 mm long and 15-20 mm wide.

[0029] In the technical solution of this application embodiment, by adjusting the thickness of the transverse and longitudinal partitions and the size of the mesh, the mesh-like separator is matched with the seedling needle of the rice transplanter. Thus, when the rice transplanter is used for transplanting, the seedling needle can accurately pick up a seedling in the mesh without modifying the rice transplanter.

[0030] Thirdly, embodiments of this application provide a seedling raising method, comprising the following steps: (1) Dry the rice seeds for 1-2 days, remove the shriveled grains, soak them in clean water for 24-48 hours until they break open and show white, and then coat them with seed coating agent to obtain pretreated seeds; (2) Place the rice seedling substrate sheet into the seedling tray and press it firmly against the seedling tray; (3) Sow the pretreated seeds on the rice seedling substrate, cover with a layer of seed-covering soil 0.3~0.5cm thick, then spray water until the seed-covering soil and rice seedling substrate are moist and the bottom of the seedling tray is no longer dripping water, and then cover the seedling tray with non-woven fabric. (4) The ambient temperature before rice seedling emergence should be controlled at around 30℃, the night temperature after rice seedling emergence should be controlled at above 15℃, and the daytime temperature after rice seedling emergence should be controlled at 20~30℃; before the seedling height reaches 2.5cm, the seedling tray should be kept moist; when the seedling growth is weak, apply quick-acting fertilizer when the seedling is in the two-leaf-one-heart stage; when the seedling is in the one-leaf-one-heart stage, mix and spray foliar fertilizer and fungicide, and remove miscellaneous plants and weeds; (5) Apply insecticide when the seedlings have 1.5 leaves, and apply a transplanting agent 2-3 days before transplanting; (6) Roll up the seedlings of the appropriate age and then transport and transplant them.

[0031] Furthermore, in some embodiments, the insecticide includes Bihu, Metalaxyl-M, and amino acid foliar fertilizer.

[0032] Furthermore, in some embodiments, the foliar fertilizer includes tricyclazole, pymetrozine, chlorantraniliprole, and amino acid foliar fertilizer.

[0033] The following are some specific embodiments. It should be noted that the embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they shall be performed in accordance with the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0034] I. Preparation Method Example 1 A method for preparing a rice seedling substrate sheet includes the following steps: (1) Preparation of decomposed straw: Rice straw and corn straw with a moisture content of 12%~18% are crushed to a particle size of 4~8mm. 8 kg of commercially available straw decomposition agent and 10 kg of urea are added to each ton of crushed dry rice and corn straw and mixed thoroughly. Water that meets the standards for agricultural irrigation water is added to bring the moisture content of the mixture to 70%. The mixed rice straw and corn straw are then placed in fermentation chambers for 10 days to obtain decomposed straw.

[0035] (2) Preparation of decomposed livestock and poultry manure: Mix 70 parts of livestock and poultry manure and 25 parts of crop straw. Add water to the mixed material to adjust the moisture content to 60%. Spray 0.04 parts of livestock and poultry manure fermentation agent evenly when mixing the materials.

[0036] Primary fermentation: The mixed materials are sent into an integrated intelligent aerobic fermentation chamber and piled up according to the chamber specifications to form a fermentation pile. It is advisable to fill the chamber. A blower is used to ventilate and aerate from the bottom of the fermentation tank every 2 hours. The fermentation temperature is kept below 65℃ for uniform aerobic fermentation. The fermentation cycle is 15 days, and the primary fermented material is then discharged for use.

[0037] Secondary fermentation: The primary fermented material is transported to the aging workshop for piling up to form a secondary fermentation pile. The secondary fermentation pile is turned over every 7 days, and the fermentation cycle is 120 days, which yields yellowish-brown or grayish-brown decomposed livestock and poultry manure.

[0038] (3) Preparation of adhesive: 100 parts of oxidized starch were dispersed in water to prepare a starch dispersion with a concentration of 40%, and heated to 65°C to gelatinize, so as to obtain starch paste; Dissolve 30 parts citric acid, 5 parts glycerol and 5 parts sodium hypophosphite in water to obtain a mixture. Add the mixture to starch paste, stir continuously, and heat to 90°C for esterification reaction for 3 hours. After the reaction is completed, add sodium bicarbonate to adjust the pH to 5 to obtain the adhesive.

[0039] (4) Mix 75 parts of decomposed straw, 15 parts of adhesive and 40 parts of rice husk biochar, spray water to adjust the moisture content to 35%, and hot press into grid-shaped separators at 150℃.

[0040] Mix 65 parts of decomposed straw, 70 parts of decomposed livestock and poultry manure and 500 parts of water, grind them into a slurry, adjust the pH to 6.0 to obtain a substrate slurry, place a grid-shaped separator in a vacuum filter, fill the mesh of the grid-shaped separator with the substrate slurry, remove the moisture from the substrate slurry by vacuum filtration, and then dry it in a drying equipment to obtain rice seedling substrate sheets.

[0041] The resulting rice seedling substrate sheet is 570mm long, 270mm wide, and 10mm thick; the grid-like separator includes transverse and longitudinal separators, the thickness of which is 2mm and the height is 10mm; the mesh of the grid-like separator is 15mm long and 15mm wide.

[0042] Example 2 A method for preparing a rice seedling substrate sheet includes the following steps: (1) Preparation of composted straw: Rice straw and corn straw with a moisture content of 12%~18% are crushed to a particle size of 4~8mm. 4 kg of commercially available straw composting agent and 15 kg of urea are added to each ton of crushed dry rice and corn straw and mixed thoroughly. Water that meets the standards for agricultural irrigation water is added to bring the moisture content of the mixture to 65%. The mixed rice straw and corn straw are then placed in fermentation chambers for 15 days to obtain composted straw.

[0043] (2) Preparation of decomposed livestock and poultry manure: Mix 65 parts of livestock and poultry manure and 30 parts of crop straw. Add water to the mixed material to adjust the moisture content to 55%. Spray 0.08 parts of livestock and poultry manure fermentation agent evenly when mixing the materials.

[0044] Primary fermentation: The mixed materials are sent into an integrated intelligent aerobic fermentation chamber and piled up according to the chamber specifications to form a fermentation pile. It is advisable to fill the chamber. A blower is used to ventilate and aerate from the bottom of the fermentation tank every 2 hours. The fermentation temperature is kept below 65℃ for uniform aerobic fermentation. The fermentation cycle is 12 days, and the primary fermented material is then discharged for use.

[0045] Secondary fermentation: The primary fermented material is transported to the aging workshop for piling up to form a secondary fermentation pile. The secondary fermentation pile is turned over every 10 days, and the fermentation cycle is 90 days, which yields yellowish-brown or grayish-brown decomposed livestock and poultry manure.

[0046] (3) Preparation of adhesive: 100 parts of oxidized starch were dispersed in water to prepare a starch dispersion with a concentration of 30%, and heated to 75°C to gelatinize, so as to obtain starch paste; Dissolve 10 parts citric acid, 15 parts glycerol and 1 part sodium hypophosphite in water to obtain a mixture. Add the mixture to starch paste, stir continuously, and heat to 130°C for esterification reaction for 1 hour. After the reaction is completed, add sodium bicarbonate to adjust the pH to 7 to obtain the adhesive.

[0047] (4) Mix 40 parts of decomposed straw, 20 parts of adhesive and 25 parts of rice husk biochar, spray water to adjust the moisture content to 45%, and hot press into grid-shaped separators at 120℃.

[0048] Mix 85 parts of decomposed straw, 50 parts of decomposed livestock and poultry manure and 500 parts of water, grind them into a slurry, adjust the pH to 6.5 to obtain a substrate slurry, place a grid-shaped separator in a vacuum filter, fill the mesh of the grid-shaped separator with the substrate slurry, remove the moisture from the substrate slurry by vacuum filtration, and then dry it in a drying equipment to obtain rice seedling substrate sheets.

[0049] The resulting rice seedling substrate sheet is 570mm long, 270mm wide, and 8mm thick; the grid-like separator includes transverse and longitudinal separators, the thickness of which is 8mm and the height of which is 8mm; the mesh of the grid-like separator is 20mm long and 20mm wide.

[0050] Example 3 A seedling raising method includes the following steps: (1) Seed preparation. Sowing was carried out on April 12th, with a seed quantity of 90g / tray. Before soaking, the rice seeds were sun-dried on an oilcloth for 2 days in sunny weather to improve seed dryness, enhance seed water absorption uniformity, and improve seedling emergence uniformity. Seeds were selected using a salt solution with a specific gravity of 1.05 to remove shriveled grains, improve seed plumpness and germination uniformity, and reduce thin and weak seedlings. The water was changed once a day for 24 hours of soaking, and the seeds were germinated for 24 hours until they emerged from the bud. Before sowing, the seeds were treated with a seed dressing agent (methyl thiophanate-methyl).

[0051] (2) Preparation of seedbed Choose a high, sheltered, sunny, well-watered, and well-drained dry land as the seedbed. Make beds about 1.5 meters wide with uniform bed size. Leave a 0.3-meter-wide ditch between the beds, with a depth of at least 0.2 meters. The surrounding ditch should be 0.2 meters wide and at least 0.2 meters deep. Before placing the seedling trays, flatten and compact the bed surface to ensure close contact between the seedling trays and the seedbed.

[0052] (3) Streamline sowing: Rice seedling substrate sheet seedling raising: Place the rice seedling substrate sheet prepared in Example 1 into the hard disk with the rough side up and the smooth side down, and press the substrate sheet and the seedling tray tightly together for later use.

[0053] Conventional nutrient soil seedling raising: direct use of hard disk for loading and unloading.

[0054] After adjusting the seeding rate and covering soil amount, the seeding production line should have a double-pipe water spraying device added after placing the seed tray and before sowing. The optimal water volume is when the seed-covering soil is thoroughly moistened but not dripping from the bottom of the seed tray. The substrate sheets and seedling trays should be manually fed directly into the integrated machine, with a seed-covering soil amount of 0.3-0.5mm, ensuring complete seed coverage. Place the sown seedling trays on the paddy field, cover them with non-woven fabric, and then spray them thoroughly with water.

[0055] (4) Seedling management 1. Temperature control: The ambient temperature in the greenhouse should be controlled at around 30℃ from sowing to emergence. After emergence, the night temperature should be controlled above 15℃ and the daytime temperature should be controlled at 20-30℃. If the temperature exceeds 35℃, ventilation should be provided to cool down the greenhouse to prevent the seedlings from being damaged by high temperature.

[0056] 2. Water management: Use micro-sprinkler irrigation for seedling raising. On sunny days, spray water thoroughly once a day around 9 am, adhering to wet sowing and dry irrigation.

[0057] 3. Remove the non-woven fabric to harden off the seedlings: Remove the non-woven fabric to harden off the seedlings in a timely manner, 5 days before transplanting.

[0058] (5) Pest and disease control. Apply pesticide for the first time when the seedlings have about 1.5 leaves, using Bihu + Metalaxyl-M • Oxyphenidyl + amino acid foliar fertilizer diluted with water and sprayed. Two days before transplanting, spray the "pre-transplanting pesticide", using 40% tricyclazole suspension + 50% pymetrozine water-dispersible granules + 20% chlorantraniliprole suspension + amino acid foliar fertilizer diluted with water and sprayed.

[0059] (6) Field transplanting and management 1. Transplanting: Transplant seedlings when they are 30 days old.

[0060] 2. Field management after transplanting: Apply 40 kg of compound fertilizer per mu as base fertilizer, apply 7 kg / mu of urea as tillering fertilizer 7 days after transplanting, and apply 15 kg / mu of potassium fertilizer as panicle fertilizer after the tillering is completed and the field is dried. Water management and pest and weed control and other related cultivation measures shall be implemented in accordance with the requirements for high-yield cultivation.

[0061] Comparative Example 1 The difference between Comparative Example 1 and Example 3 is that conventional nutrient soil was used instead of rice seedling substrate sheets. The conventional nutrient soil was prepared by mixing 1,000 parts of sieved fine soil and 1 part of seedling strengthening agent. The conventional nutrient soil was laid in the seedling tray with a bottom soil thickness of 1.5 cm and a plain soil thickness of 0.5 cm, weighing about 7 catties per tray. The other steps were the same as in Example 3.

[0062] Comparative Example 2 The difference between Comparative Example 2 and Example 3 is that the rice seedling substrate sheet used only contains substrate material and does not have grid-like separators. All other steps are the same as in Example 3.

[0063] II. Testing Methods 1. Seedling Quality Survey: Before transplanting, 100 representative seedlings (4 trays, 25 seedlings per tray) were taken from each treatment. Morphological characteristics such as seedling height, leaf age, stem base diameter, number of adventitious roots per seedling (number of roots longer than 5mm), and longest root length were measured. Simultaneously, the seedling roots were washed clean, and the roots and stems / leaves were cut at the base. The fresh weight of the above-ground and underground parts of the seedlings was measured. They were then placed in an oven at 105℃ for blanching, and then dried at 60℃ until constant weight. The dry weight of the above-ground and underground parts was measured. The seedling survival rate was measured before transplanting. Data Processing and Analysis: The data obtained in the experiment were processed and analyzed using WPS software.

[0064] 2. Transplanting quality survey: After rice seedlings were transplanted to the field using a rice transplanter, 5 points were randomly selected in each treatment field, with 20 holes at each point. The number of seedlings per hole, the rate of damaged seedlings, the rate of floating seedlings, and the rate of missing seedlings were investigated.

[0065] III. Analysis of Test Results for Each Embodiment and Comparative Example (1) The seedlings were raised using the methods in Example 3 and Comparative Examples 1-2. The seedling rate, seedling density and seedling weight are shown in Table 1 below.

[0066] Table 1

[0067] Under the same management conditions, the rice seedling substrate sheet in Example 3 of this invention has a higher seedling survival rate than Comparative Examples 1 and 2, and a significantly higher seedling survival rate compared to the conventional nutrient soil in Comparative Example 1. The seedling density in Example 3 is higher than that in Comparative Example 1, but slightly lower than that in Comparative Example 2, because the presence of the separator reduces the seedling density. The seedling weight in Example 3 is significantly lower than that in Comparative Example 1, but slightly higher than that in Comparative Example 2, because the density of the separator is slightly heavier than that of the substrate material. From the above data, it can be seen that the seedling raising performance using the method in Example 3 is significantly higher than that of conventional nutrient soil, and not significantly different from that of the substrate sheet without separators.

[0068] (2) The seedling quality test results obtained by raising seedlings using the methods in Example 3 and Comparative Examples 1-2 are shown in Table 2 below.

[0069] Table 2

[0070] As can be seen from Table 2, the rice seedlings cultivated using the rice seedling substrate sheets of this invention have a higher overall quality, with more roots and stronger seedlings. The root length is slightly shorter due to the obstruction of the barrier components. Because the rice seedling substrate sheets have better air permeability than conventional nutrient soil, which is conducive to root growth, each seedling has more roots. Due to the effect of the barrier components, the seedling density in Example 3 is lower than that in Comparative Example 2. Therefore, the seedlings in Example 3 are taller and have thicker stem bases.

[0071] (3) The seedlings obtained in Example 3 and Comparative Examples 1-2 were transplanted into the field using a rice transplanter with the same performance of the rice transplanter, the same operator and the same parameters. The quality of the transplanting in the field was statistically analyzed and the results are shown in Table 3.

[0072] Table 3

[0073] As can be seen from Table 3, the seedling damage rate of the method in Example 3 is greatly reduced, and the seedlings can turn green again 4 days after machine transplanting. The seedlings raised in the substrate sheet survive quickly and can promote effective tillering at an early stage.

[0074] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and function as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A method for preparing a rice seedling substrate sheet, characterized in that, Comprising the following steps: S1, after mixing the rotten straw, adhesive and biochar, spray water to adjust the moisture content to 50%-60%, hot-press into a grid-shaped separator at a temperature of 120-150 DEG C; the mass ratio of the rotten straw, adhesive and biochar is (8-15):(3-4):(5-8); S2, after mixing and stirring the rotten straw, rotten livestock and poultry manure and water, pulp, adjust the pH to 6.0-6.5, get the substrate slurry; the mass ratio of the rotten straw, rotten livestock and poultry manure and water is (13-17):(10-14):100; S3, the substrate slurry is filled into the mesh of the grid-shaped separator, vacuum suction filtration molding, drying, get the rice seedling raising substrate piece.

2. The method for preparing a rice seedling raising substrate sheet according to claim 1, characterized in that, The preparation method of the rotten straw comprises the following steps: The straw is crushed to a particle size of 4-8 mm, the straw rotting bacteria agent and nitrogen source are added, water is added to adjust the moisture content to 65%-70%, and the first premix is obtained; the mass ratio of the first premix is 1000:(4-8):(10-15); The first premix is subjected to closed aerobic fermentation for 10-15 days to obtain the rotten straw.

3. The method for preparing a rice seedling raising substrate sheet according to claim 1, characterized in that, The straw comprises at least one of rice straw and corn straw; and / or The nitrogen source comprises urea.

4. The method for preparing a rice seedling raising substrate sheet according to claim 1, characterized in that, The preparation method of the rotten livestock and poultry manure comprises the following steps: The livestock and poultry manure and the straw are mixed in a weight ratio of 7:3, the straw rotting bacteria agent is uniformly added during mixing, and the moisture content of the mixed material is adjusted to 55%-60% to obtain a second premix; the mass ratio of the second premix is (25-30):(65-70):(0.04-0.08); The second premix is subjected to aerobic fermentation at 60-65 DEG C for 12-15 days to obtain a first fermentation material; The first fermentation material is subjected to anaerobic fermentation, and the pile is turned every 7-10 days, and the anaerobic fermentation is carried out for 90-120 days to obtain the rotten livestock and poultry manure.

5. The method of claim 1, wherein the rice seedling raising substrate sheet is prepared by mixing the rice seedling raising substrate with the water in the amount of 10 to 30 wt% based on the total weight of the rice seedling raising substrate. The adhesive is prepared from oxidized starch, citric acid and glycerol, and the mass ratio of the oxidized starch, citric acid and glycerol is 100:(10-30):(5-15).

6. The method for preparing a rice seedling raising substrate sheet according to claim 1, characterized in that, The biochar is rice husk biochar.

7. A rice seedling substrate sheet, characterized in that, The preparation method is prepared by any one of claims 1-6.

8. The rice seedling raising substrate sheet according to claim 7, wherein The rice seedling raising substrate piece comprises a grid-shaped separator and a substrate material filled in the mesh of the grid-shaped separator; The rice seedling raising substrate piece is 570 mm long, 270 mm wide, and 8-12 mm thick; The grid-shaped separator comprises a transverse partition and a longitudinal partition, the thickness of the transverse partition and the longitudinal partition is 2-3 mm, and the height is 8-12 mm; the mesh of the grid-shaped separator is 15-20 mm long and 15-20 mm wide.

9. A method of raising seedlings, characterized by, Comprising the following steps: (1) the rice seeds are exposed to the sun for 1-2 days, the shriveled grains are removed, the seeds are soaked in water for 24-48 hours to break the chest and expose the white, and the seeds are coated with seed dressing to obtain pretreated seeds; (2) the rice seedling raising substrate piece in claim 7 is placed in a seedling raising tray, and the rice seedling raising substrate piece is tightly pressed with the seedling raising tray; (3) The pretreated seeds are sowed on the rice seedling raising substrate sheet, covered with a 0.3-0.5 cm thick seed covering soil, then watered until the seed covering soil and the rice seedling raising substrate sheet are moistened and the bottom of the seedling raising tray does not drip water, and then non-woven fabric is covered on the seedling raising tray; (4) The ambient temperature before the rice seeds germinate is controlled at about 30°C, the night temperature after the rice seeds germinate is controlled at above 15°C, and the day temperature after the rice seeds germinate is controlled at 20-30°C; the seedling raising tray is kept moist before the seedlings grow to a height of 2.5 cm; when the seedlings grow weakly, the seedlings are applied with quick-acting fertilizer when they are at the two-leaf-one-heart stage; the seedlings are mixedly sprayed with foliar fertilizer and fungicide when they are at the one-leaf-one-heart stage, and the seedlings are weeded; (5) The seedlings are applied with insect prevention medicine when they have 1.5 leaves, and are applied with transplanting medicine 2-3 days before transplanting; (6) The well-raised seedlings of suitable age are rolled up, and then transplanted.

10. The seedling raising method according to claim 9, characterized by, The insect prevention medicine comprises Bihuo, thiophanate-methyl and oxycarboxin, and / or the transplanting medicine comprises tricyclazole, pymetrozine, chlorantraniliprole and amino acid foliar fertilizer. The insect prevention medicine comprises Bihuo, thiophanate-methyl and oxycarboxin, and / or the transplanting medicine comprises tricyclazole, pymetrozine, chlorantraniliprole and amino acid foliar fertilizer.

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