Biomass seedling raising matrix box and preparation method thereof

Abstract

The present invention discloses a biomass seedling raising matrix box and its preparation method, relating to the field of rice seedling raising technology. The method comprises the following steps: Step 1: Cut corn stalks into segments, crush them, and sieve them, with the unsieved portion being undecomposed corn stalks; fermenting the undecomposed corn stalks to obtain decomposed corn stalks; Step 2: Thoroughly mixing the undecomposed corn stalks and decomposed corn stalks to obtain a mixture; adding nutrient fertilizers and mixing them uniformly, and adding dilute sulfuric acid to adjust the pH to obtain a matrix raw material; adding a binder and dissolving it in water, and adding other additives and mixing them uniformly to obtain an additive; Step 3: Thoroughly mixing the matrix raw material and the additives, and pressing and forming them to obtain a seedling raising matrix tray; Step 4: Covering the bottom of the seedling raising matrix tray with a plastic film to obtain a biomass seedling raising matrix box. This application prepares a biomass rice seedling raising matrix box using only corn stalks, promoting the commercialization, standardization, and simplification of rice seedling raising technology.

Description

Technical Field

[0001] The invention relates to the technical field of rice seedling cultivation, in particular to a biomass rice seedling cultivation matrix box and a preparation method thereof. Background Art

[0002] With the development of agricultural modernization, traditional methods of raising rice seedlings have become unable to meet the needs of large-scale and efficient rice seedling production due to problems such as difficulty in obtaining soil and high costs. As a new method of raising rice seedlings, the seedling matrix box has become an important direction for the development of agricultural science and technology due to its advantages such as environmental protection, low cost and simplicity.

[0003] In the prior art, the traditional rice seedling raising matrix box is mainly composed of a plastic tray for raising rice seedlings and a seedling raising matrix; however, there are the following problems: on the one hand, when the seedling raising matrix box is converted into a seedling raising matrix, there is a relatively troublesome separation step, and the long-term use of plastic materials in the seedling raising matrix affects the amount of seedlings raised. On the other hand, common seedling raising matrices generally only consider the influence of the nutrients in the matrix on its seedling raising properties, such as patent CN202410609876.X discloses a processing method for preparing a seedling raising matrix using rice straw, CN202410475630.8 provides a large-scale rice seedling raising method, and CN202410243065.2 discloses a seedling raising matrix and its preparation method and application, etc.; none of them considers the mechanical strength problem that the seedling raising matrix needs to bear when it is transferred into a seedling raising matrix.

[0004] Furthermore, there are the following drawbacks: the nutrient matrix for rice seedlings is primarily composed of peat, peaty soil, and topsoil from cultivated land. The indiscriminate extraction of these non-renewable resources has caused irreversible damage to the ecological environment. Furthermore, the raw material supply for rice seedling matrix is in short supply, severely impacting the quality of rice seedlings and rice yields. The burning of large quantities of unusable corn stalks also causes severe air pollution, necessitating the utilization of corn stalks as a renewable resource.

[0005] In summary, it is of great significance to solve the above problems and prepare a biomass seedling raising matrix box. Summary of the Invention

[0006] The present invention aims to develop a biomass seedling raising substrate box and a method for preparing it, using a widely available, renewable, and environmentally friendly raw material to manufacture a rice seedling raising tray that integrates a rice seedling raising substrate and a rice seedling raising tray. This method replaces the currently widely used plastic rice seedling raising trays and addresses the problems mentioned in the prior art, such as the shortage of raw materials for rice seedling raising substrates, the environmental pollution caused by plastic rice seedling raising trays, the high production costs of rice seedlings, and the mechanical strength issues during the rice seedling raising and seedling conversion process. The present invention also provides a biomass rice seedling raising substrate box and a method for preparing the same.

[0007] The present invention provides the following technical solution: a method for preparing a biomass seedling raising matrix box, comprising the following steps:

[0008] Step 1: (1) cutting and crushing the corn stalks, and sieving them through a sieve with an aperture of 4 mm × 4 mm. The unscreened portion is regarded as the undecomposed corn stalks; (2) fermenting the undecomposed corn stalks to obtain decomposed corn stalks;

[0009] Step 2: (1) fully mix the undecomposed corn straw and the decomposed corn straw to obtain a mixture; add nutrient fertilizer and mix evenly; add dilute sulfuric acid to adjust the pH to 5-6 to obtain a matrix raw material; (2) add a binder to dissolve it in water, add other additives and mix evenly to obtain an additive;

[0010] Step 3: fully mix the matrix raw materials and additives, and press them into shape to obtain a seedling raising matrix tray;

[0011] Step 4: Put a plastic film on the bottom of the seedling raising matrix tray to obtain a biomass seedling raising matrix box.

[0012] More optimally, the raw materials of the seedling raising substrate tray include the following components: by weight, 40-48 parts of undecomposed corn stalks, 52-60 parts of decomposed corn stalks, 4-12 parts of nutrient fertilizers, 0.2-2 parts of adhesives, and 0.01-1 parts of other additives;

[0013] The other added ingredients include one or more of trace elements and fungicides; the raw materials of the adhesive include one or two of polyvinyl alcohol and flour; the nutrient fertilizers include nitrogen fertilizer, phosphorus fertilizer and potassium sulfate, the nitrogen fertilizer includes one or two of ammonium sulfate and urea, and the phosphorus fertilizer includes one or more of superphosphate, monoammonium phosphate and diammonium phosphate.

[0014] More optimally, the width of the connection between the plastic film and the bottom of the seedling raising matrix tray is 2 to 4 cm.

[0015] More optimally, the decomposed corn straw preparation process is as follows: S2-1: adding undecomposed corn straw to a 1-1.5 wt% citric acid solution, setting a liquid-to-solid ratio of 10-12:1, pretreating at room temperature for 2-3 hours, sterilizing, separating, and drying to obtain a straw raw material;

[0016] S2-2: Add wood vinegar with a pH of 5.5±0.2 and a complex enzyme to the straw raw material, stir and activate at 45-50°C and a speed of 100-200 rpm for 8-10 hours to obtain a fermentation raw material;

[0017] S2-3: Spread the fermentation raw materials flat, add water, and add fermentation liquid; compost and ferment at 50-60°C for 7-10 days, constantly turning the compost during the process to obtain decomposed material; sieve the compost using a sieve with an aperture of 8mm×8mm, dry the sieved material, and obtain decomposed corn stalks.

[0018] More optimally, during the preparation of the fermentation raw material, the mass ratio of the straw raw material, wood vinegar, and complex enzyme is 10-12:2:0.2; the complex enzyme includes laccase, lignin peroxidase, phosphoenolpyruvate carboxylase, and acetyl-CoA carboxylase in a mass ratio of 1:0.7:0.2:0.1;

[0019] During the preparation of the compost, the amount of water added is 1 to 1.2 times the amount of the fermentation raw material; the amount of fermentation liquid added accounts for 4 to 5wt% of the fermentation raw material; the fermentation liquid includes a thermoviolet Streptomyces liquid, a gametoderma liquid, a thermophilic siderophore liquid, a Lactobacillus plantarum liquid, a Bacillus subtilis liquid, and a Corynebacterium glutamicum liquid in a mass ratio of 3:2:2:1.5:1:0.5.

[0020] More optimally, the process parameters of the compression molding are: temperature of 100-120°C, pressure of 12-15 MPa, and time of 100-110 s.

[0021] In a further embodiment, the binder comprises a polyvinyl alcohol complex and modified flour in a mass ratio of 5:3.

[0022] More optimally, the preparation process of the polyvinyl alcohol complex comprises the following steps: adding montmorillonite to water and uniformly dispersing it by ultrasonication to obtain a 0.01-0.02 g / mL dispersion; adding 0.05-1 mol / L protocatechuic acid and stirring for 1-2 hours; adding ammonium molybdate and continuing to stir for 2-3 hours; adding catechol-based polyvinyl alcohol, heating to 80-85° C. and stirring for 1-2 hours, filtering, and drying to obtain the polyvinyl alcohol complex;

[0023] The raw materials of the polyvinyl alcohol compound include the following substances: 1-1.2 parts of montmorillonite, 0.2-0.3 parts of protocatechuic acid, 0.04-0.06 parts of ammonium molybdate, and 4-5 parts of catechol-based polyvinyl alcohol, in parts by weight.

[0024] More optimally, the preparation process of the modified flour includes the following steps: mixing succinic anhydride and diethylenetriamine in a molar ratio of 0.6-0.8:1, stirring at 50-55°C for 1-2 hours, heating to 100-120°C and stirring for 1-2 hours to obtain a branched product; adding the branched product to water and stirring evenly to obtain a 5-8wt% mixed solution; adjusting the pH to 5.2±0.3; adding aldehyde-modified flour, stirring at 60-65°C for 10-20 minutes, centrifuging, and drying to obtain modified flour; wherein the mass ratio of aldehyde-modified flour to branched product is 1:0.4-0.5.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The present invention uses corn stalks as a raw material and compounds other additives to produce a rice seedling raising substrate tray; the tray has excellent applicability for rice seedling raising. Using corn stalks as a raw material has the following advantages: first, it solves the current shortage of raw materials for rice seedling raising substrates and reduces the ecological damage caused by the unrestricted excavation of peat, peat soil, and cultivated topsoil; second, it seeks a new way to return corn stalks to the fields and reduces the environmental pollution caused by the burning of corn stalks; third, it reduces the introduction of waste plastics and the pollution of rice seedling trays to the environment; and fourth, it reduces the cost of rice seedling raising.

[0027] (2) The seedling raising matrix tray of the present invention integrates the seedling raising matrix and the seedling raising tray. It is both a seedling raising tray and a seedling raising matrix, and has dual functions. There is no need to add any seedling raising matrix or seedling raising soil when sowing directly on the seedling raising matrix tray. After watering, it automatically expands so that the physical properties of the matrix meet the requirements for seedling raising. At the same time, it is both a seedling raising tray and the lower matrix for seedling raising and sowing. The multiple cropping matrix cover is the multiple cropping matrix; there is no need to add any seedling raising matrix or seedling raising soil when sowing directly on the seedling raising tray. After sowing, the matrix cover of the present invention is placed on its surface to replace the multiple cropping matrix or multiple cropping seedling soil. After the rice seedlings are grown, the seedling raising tray is transformed into a seedling raising matrix, which is directly transplanted into the field along with the rice seedlings and becomes organic matter for fertilizing the field.

[0028] (3) The present invention adds a 2-4 cm wide plastic film to the bottom corner of the seedling raising matrix tray, which can enhance the mechanical strength of the seedling raising matrix tray and prevent the rice seedling roots from looping between the trays.

[0029] (4) In this application, the raw materials of the seedling substrate tray are nutritionally adjusted, the pH value is adjusted, and fungicides for the prevention and control of diseases that are prone to occur in the seedlings are added, so that the rice seedling technology can be commercialized and easily mastered by the majority of rice farmers, making the rice seedling technology standardized and unified.

[0030] (5) This application aims to further enhance the rice seedling raising ability and solve the problem of poor mechanical strength of the existing seedling raising matrix tray. In the scheme, the rice seedling raising ability and mechanical strength of the seedling raising matrix tray are effectively improved by limiting the process of specific decomposition of corn straw, optimizing the ratio of undecomposed and decomposed corn straw, and introducing a specific adhesive.

[0031] Among them, the decomposed corn straw is first treated with a citric acid solution, then introduced into a complex enzyme containing phosphoenolpyruvate carboxylase and acetyl-CoA carboxylase, and finally decomposed in a complex bacterial solution containing Corynebacterium glutamicum. Compared with the common decomposition process, citric acid pretreatment can effectively improve the degradation of cellulose, provide a better environment for subsequent fermentation, promote fermentation, and increase humus. The phosphoenolpyruvate carboxylase introduced subsequently can participate in the citric acid cycle and cooperate with acetyl-CoA carboxylase to promote Corynebacterium glutamicum to produce glutamate derivatives in the subsequent fermentation process; and this type of substance can be used as a promoter to improve the utilization rate of fertilizers, improve the soil microbial environment, and promote rice seedling cultivation.

[0032] Among them, in the ratio of undecomposed corn straw to decomposed corn straw, undecomposed corn straw can improve the mechanical strength of the seedling substrate, while decomposed corn straw can ensure the water holding and fertilizer absorption and retention capacity of the seedling substrate; therefore, when using crop straw as raw material to make substrate seedling trays and seedling substrates, the first thing to consider is the degree of decomposition (rottenness) of the straw and the mixing ratio of the two;

[0033] While increasing the proportion of undecomposed corn straw improves mechanical strength, exceeding 50% can negatively impact rice seedling cultivation. Excessive amounts of undecomposed corn straw as a substrate can cause rice seedlings to turn yellow or even die. This is because during microbial decomposition, much of the nitrogen in the straw is utilized by microorganisms, leading to nitrogen deficiency in the rice seedlings, resulting in weakness or even death. Therefore, the amount of undecomposed corn straw introduced should be limited to less than 50%.

[0034] Among them, most of the current seedling trays made from crop straw only serve as seedling trays and do not function as a seedling substrate. Therefore, during the seedling raising process, seedling substrate or soil must be installed. Generally, a seedling tray must bear about 3kg of seedling substrate or soil. The finished seedling tray must have sufficient mechanical strength to support a weight of 3kg. The materials and adhesives used in the production are required to give the finished seedling tray strong mechanical strength to ensure that the seedling tray does not break during transportation after sowing. The required crop straw material cannot be decomposed, and the adhesive must have strong adhesion. Putting the finished seedling tray and seedlings into a transplanter together for transplanting will cause damage to the seedlings. In addition, generally strong adhesives are not easy to decompose and will cause soil pollution.

[0035] Therefore, the present application chooses polyvinyl alcohol as the main adhesive, and uses flour as an auxiliary bonding agent to improve the strength. The use of these two as adhesives has the following advantages: First, it has good water stability. After being made into a seedling tray, it will not disperse due to water, and the original state of the seedling tray will be maintained. Second, it has good elasticity and scalability. After being in contact with water, the seedling tray has a certain degree of expansion, so that the physical properties of the matrix after the seedling tray is sown and watered are suitable for seedling cultivation needs. Third, it can be decomposed in a short time after transplanting, and will not cause pollution to the soil and other environments. Fourth, the shear force generated is small, and there is no obvious effect on the seedlings grown in the matrix seedling tray during mechanical transplanting.

[0036] Furthermore, in a further approach, polyvinyl alcohol is grafted with catechol and then combined with molybdate-loaded montmorillonite to form a polyethylene composite. The hardness of montmorillonite can increase soil porosity and water retention, while its ion exchange capacity promotes the slow release of nutrients, improving their absorption and utilization by seedlings. The introduction of montmorillonite can also improve bonding strength. The introduction of molybdate can promote the activity of endogenous nitrate reductase and other enzymes in rice plants, promoting root growth and development, enhancing photosynthesis, and enhancing seedling growth. Furthermore, flour is formaldehyde-modified and then grafted with branched products to produce modified flour. This modification effectively enhances hydrogen bonding and promotes the crosslinking of proteins and polysaccharides in decomposed corn straw, thereby helping to improve the strength of the seedling medium.

[0037] At the same time, the plan limits the temperature, pressure and time of the molding process. Under this process, the porosity of the material can be effectively guaranteed on the basis of effectively ensuring the mechanical strength, and the germination and emergence of seeds during the seedling cultivation process can be guaranteed.

[0038] In summary, the present invention prepares a rice seedling raising matrix box based on corn straw, which can replace the traditional plastic rice seedling raising tray and realize the commercialization, standardization and simplification of rice seedling raising technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a product picture of the biomass seedling raising matrix box of the present invention. DETAILED DESCRIPTION

[0040] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0041] In the following embodiments, parts are by mass, and the plastic film is a polyethylene ground film.

[0042] The fermentation bacterial liquid consists of a thermoviolaceous Streptomyces liquid, a Trichoderma gaimsii liquid, a thermophilic Sporangium liquid, a Lactobacillus plantarum liquid, a Bacillus subtilis liquid, and a Corynebacterium glutamicum liquid in a mass ratio of 3:2:2:1.5:1:0.5; and is prepared using existing technology.

[0043] The complex enzyme consists of laccase, lignin peroxidase, phosphoenolpyruvate carboxylase and acetyl-CoA carboxylase in a mass ratio of 1:0.7:0.2:0.1.

[0044] Preparation of polyvinyl alcohol complex: (1) 10 g polyvinyl alcohol and 14 g carbonyldiimidazole were added to 150 mL of dimethyl sulfoxide in sequence and stirred at room temperature for 2 hours; 50 mL of ethylenediamine was added dropwise and stirred at 50 °C for 24 hours, washed and dried to obtain ethylenediamine-based polyvinyl alcohol; 5 g of ethylenediamine-based polyvinyl alcohol was added to 100 mL of water, 2.2 g of EDC and 1.5 g of 3,4-dihydroxycinnamic acid were added and stirred evenly, the pH was adjusted to 5.6, stirred for 12 hours, purified and dried to obtain catechol-based polyvinyl alcohol; (2) 1 g of montmorillonite was added to water and ultrasonically dispersed to obtain a 0.01 g / mL dispersion; 0.05 mol / L protocatechuic acid solution (containing 0.3 g protocatechuic acid) was added and stirred for 1 hour; 0.05 g of ammonium molybdate was added and stirred for 2 hours; 5 g of catechol-based polyvinyl alcohol was added, the temperature was raised to 80 °C and stirred for 2 hours, filtered and dried to obtain a polyvinyl alcohol complex.

[0045] The preparation process of modified flour includes the following steps: (1) adding 10 g of flour to 50 mL of water and stirring evenly, adjusting the pH to 9.2, adding 0.2 g of hydrogen peroxide, stirring for 1.5 hours, adding 1 g of 30 wt% sodium bisulfite solution and stirring for 0.5 hours, adjusting the pH to 6.8, purifying and drying to obtain formaldehyde-modified flour; (2) mixing succinic anhydride and diethylenetriamine in a molar ratio of 0.8:1, stirring at 55 ° C for 2 hours, heating to 120 ° C and stirring for 1 hour to obtain a branched product; (3) adding 0.8 g of the branched product to 100 mL of water and stirring evenly to obtain a 5 wt% mixed solution; adjusting the pH to 5.4; adding 2 g of formaldehyde-modified flour, stirring at 60 ° C for 20 minutes, centrifuging and drying to obtain modified flour.

[0046] Example 1: A method for preparing a biomass seedling raising matrix box, comprising the following steps:

[0047] Step 1: (1) Cut corn straw into 2 cm segments, crush them, and sieve them with a sieve with an aperture of 4 mm × 4 mm. The unsieved part is used as undecomposed corn straw; (2) Preparation of decomposed corn straw: S2-1: Add undecomposed corn straw to 1 wt% citric acid solution, set the liquid-solid ratio to 10:1, pretreat at room temperature for 2 hours, sterilize, separate, and dry to obtain straw raw material; S2-2: Add wood vinegar with pH = 5.6 and complex enzyme to the straw raw material; straw raw material, wood vinegar, and complex enzyme are added to the straw raw material. The mass ratio of vinegar solution to complex enzyme is 10:2:0.2; the mixture is stirred and activated at 50°C at a speed of 200 rpm for 10 hours to obtain a fermentation raw material; S2-3: the fermentation raw material is spread evenly, water is added, and the amount of water added is 1 times the amount of the fermentation raw material; a fermentation bacterial liquid is added, and the amount of the fermentation bacterial liquid added is 5wt% of the fermentation raw material; the compost is fermented at 55°C for 10 days with continuous stirring during the process to obtain a decomposed material; the compost is sieved using a sieve with an aperture of 8 mm × 8 mm, and dried after sieving to obtain a decomposed corn stalk;

[0048] Step 2: (1) 45 parts of undecomposed corn straw and 55 parts of decomposed corn straw were fully stirred to obtain a mixture; 8 parts of nutrient fertilizer (3 parts of ammonium sulfate, 1 part of urea, 3 parts of heavy superphosphate, and 1 part of potassium sulfate, which were pre-crushed through a 20-mesh sieve) were added and mixed evenly, and dilute sulfuric acid was added to adjust the pH to 5.6 to obtain a matrix raw material; (2) 1 part of a binder (polyvinyl alcohol and flour in a mass ratio of 5:3) was added to water, heated to 90°C and stirred to dissolve to obtain an 8wt% solution, and 0.032 parts of other additives (0.03 parts of zinc sulfate and 0.002 parts of dioxon) were added to obtain an additive;

[0049] Step 3: The matrix raw materials and additives are fully mixed, pressed at a temperature of 110°C and a pressure of 14 MPa for 110 seconds, and dried to a moisture content of 8% to obtain a seedling raising matrix tray;

[0050] Step 4: Put a plastic film with a width of 3 cm on the bottom of the seedling raising matrix tray to obtain a biomass seedling raising matrix box.

[0051] Example 2: A method for preparing a biomass seedling raising matrix box, comprising the following steps:

[0052] Step 1: (1) Cut corn straw into 2 cm segments, crush them, and sieve them with a sieve with an aperture of 4 mm × 4 mm. The unsieved part is used as undecomposed corn straw; (2) Preparation of decomposed corn straw: S2-1: Add undecomposed corn straw to 1 wt% citric acid solution, set the liquid-solid ratio to 10:1, pretreat at room temperature for 2 hours, sterilize, separate, and dry to obtain straw raw material; S2-2: Add wood vinegar with pH = 5.6 and complex enzyme to the straw raw material; Straw raw material The mass ratio of wood vinegar and complex enzyme is 10:2:0.2; the mixture is stirred and activated at 50°C at a speed of 200 rpm for 10 hours to obtain a fermentation raw material; S2-3: the fermentation raw material is spread out, water is added, and the amount of water added is 1 times the amount of the fermentation raw material; fermentation liquid is added, and the amount of fermentation liquid added accounts for 5wt% of the fermentation raw material; the compost is fermented at 55°C for 10 days, and the compost is continuously turned during the process to obtain a decomposed material; the compost is sieved using a sieve with an aperture of 8mm×8mm, and dried after sieving to obtain a decomposed corn stalk;

[0053] Step 2: (1) 45 parts of undecomposed corn straw and 55 parts of decomposed corn straw were fully mixed to obtain a mixture; 8 parts of nutrient fertilizer (3 parts of ammonium sulfate, 1 part of urea, 3 parts of heavy superphosphate, and 1 part of potassium sulfate, which were pre-crushed through a 20-mesh sieve) were added and mixed evenly, and dilute sulfuric acid was added to adjust the pH to 5.6 to obtain a matrix raw material; (2) 1.6 parts of a binder (polyvinyl alcohol complex and modified flour in a mass ratio of 5:3) were added to water, heated to 90°C and stirred to dissolve to obtain an 8 wt% solution, and 0.032 parts of other additives (0.03 parts of zinc sulfate and 0.002 parts of dioxon) were added to obtain an additive;

[0054] Step 3: The matrix raw materials and additives are fully mixed, pressed at a temperature of 110°C and a pressure of 14 MPa for 110 seconds, and dried to a moisture content of 8% to obtain a seedling raising matrix tray;

[0055] Step 4: Put a plastic film with a width of 3 cm on the bottom of the seedling raising matrix tray to obtain a biomass seedling raising matrix box.

[0056] Example 3: A method for preparing a biomass seedling raising matrix box, comprising the following steps:

[0057] Step 1: (1) Cut corn straw into 2 cm segments, crush them, and sieve them with a sieve with an aperture of 4 mm × 4 mm. The unsieved part is used as undecomposed corn straw; (2) Preparation of decomposed corn straw: S2-1: Add undecomposed corn straw to 1 wt% citric acid solution, set the liquid-solid ratio to 10:1, pretreat at room temperature for 2 hours, sterilize, separate, and dry to obtain straw raw material; S2-2: Add wood vinegar with pH = 5.6 and complex enzyme to the straw raw material; straw raw material, wood vinegar, and complex enzyme are added to the straw raw material. The mass ratio of vinegar solution to complex enzyme is 10:2:0.2; the mixture is stirred and activated at 50°C at a speed of 200 rpm for 10 hours to obtain a fermentation raw material; S2-3: the fermentation raw material is spread evenly, water is added, and the amount of water added is 1 times the amount of the fermentation raw material; a fermentation bacterial liquid is added, and the amount of the fermentation bacterial liquid added is 5wt% of the fermentation raw material; the compost is fermented at 55°C for 10 days with continuous stirring during the process to obtain a decomposed material; the compost is sieved using a sieve with an aperture of 8 mm × 8 mm, and dried after sieving to obtain a decomposed corn stalk;

[0058] Step 2: (1) 40 parts of undecomposed corn straw and 60 parts of decomposed corn straw were fully mixed to obtain a mixture; 8 parts of nutrient fertilizer (3 parts of ammonium sulfate, 1 part of urea, 3 parts of heavy superphosphate, and 1 part of potassium sulfate, which were pre-crushed through a 20-mesh sieve) were added and mixed evenly, and dilute sulfuric acid was added to adjust the pH to 5.7 to obtain a matrix raw material; (2) 0.4 parts of a binder (polyvinyl alcohol complex and modified flour in a mass ratio of 5:3) were added to water, heated to 90°C and stirred to dissolve to obtain an 8 wt% solution, and 0.032 parts of other additives (0.03 parts of zinc sulfate and 0.002 parts of dioxon) were added to obtain an additive;

[0059] Step 3: The matrix raw materials and additives are fully mixed, pressed at a temperature of 120°C and a pressure of 15 MPa for 110 seconds, and dried to a moisture content of 8% to obtain a seedling raising matrix tray;

[0060] Step 4: Put a plastic film with a width of 3 cm on the bottom of the seedling raising matrix tray to obtain a biomass seedling raising matrix box.

[0061] Example 4: A method for preparing a biomass seedling raising matrix box, comprising the following steps:

[0062] Step 1: (1) Cut corn straw into 2 cm segments, crush them, and sieve them with a sieve with an aperture of 4 mm × 4 mm. The unsieved part is used as undecomposed corn straw; (2) Preparation of decomposed corn straw: S2-1: Add undecomposed corn straw to 1 wt% citric acid solution, set the liquid-solid ratio to 10:1, pretreat at room temperature for 2 hours, sterilize, separate, and dry to obtain straw raw material; S2-2: Add wood vinegar with pH = 5.6 and complex enzyme to the straw raw material; straw raw material, wood vinegar, and complex enzyme are added to the straw raw material. The mass ratio of vinegar solution to complex enzyme is 10:2:0.2; the mixture is stirred and activated at 50°C at a speed of 200 rpm for 10 hours to obtain a fermentation raw material; S2-3: the fermentation raw material is spread evenly, water is added, and the amount of water added is 1 times the amount of the fermentation raw material; a fermentation bacterial liquid is added, and the amount of the fermentation bacterial liquid added is 5wt% of the fermentation raw material; the compost is fermented at 55°C for 10 days with continuous stirring during the process to obtain a decomposed material; the compost is sieved using a sieve with an aperture of 8 mm × 8 mm, and dried after sieving to obtain a decomposed corn stalk;

[0063] Step 2: (1) 48 parts of undecomposed corn straw and 52 parts of decomposed corn straw were fully stirred to obtain a mixture; 8 parts of nutrient fertilizer (3 parts of ammonium sulfate, 1 part of urea, 3 parts of heavy superphosphate, and 1 part of potassium sulfate, which were pre-crushed through a 20-mesh sieve) were added and mixed evenly, and dilute sulfuric acid was added to adjust the pH to 5.6 to obtain a matrix raw material; (2) 2 parts of a binder (polyvinyl alcohol complex and modified flour in a mass ratio of 5:3) were added to water, heated to 90°C and stirred to dissolve to obtain an 8wt% solution, and 0.032 parts of other additives (0.03 parts of zinc sulfate and 0.002 parts of dioxon) were added to obtain an additive;

[0064] Step 3: fully mix the matrix raw materials and additives, press at a temperature of 100°C and a pressure of 12 MPa for 100 seconds, and dry and shape to a moisture content of 8% to obtain a seedling culture matrix tray;

[0065] Step 4: Put a plastic film with a width of 3 cm on the bottom of the seedling raising matrix tray to obtain a biomass seedling raising matrix box.

[0066] Comparative Example 1: Based on Example 1, the fineness of the undecomposed corn stalks is that the length of the stalk skin and fibers is less than 20 mm, and the fineness of the decomposed corn stalks is particles with a sieve aperture of 8 mm × 8 mm; the rest is the same as Example 1.

[0067] Comparative Example 2: Based on Example 1, the ratio of undecomposed corn straw to decomposed corn straw was adjusted to 55 parts of undecomposed corn straw and 45 parts of decomposed corn straw; the rest was the same as Example 1.

[0068] Comparative Example 3: Based on Example 1, citric acid pretreatment, lignin peroxidase, phosphoenolpyruvate carboxylase, and acetyl-CoA carboxylase were not introduced into the preparation process of decomposed corn straw; the rest was the same as Example 1, except for the following steps: (1) the corn straw was cut into 2 cm segments, crushed, and sieved using a sieve with an aperture of 4 mm × 4 mm. The unsieved portion was used as the undecomposed corn straw; (2) Preparation of decomposed corn straw: S2-1: wood vinegar with a pH of 5.6 and a complex enzyme were added to the undecomposed corn straw; the straw raw material, wood vinegar, and complex enzyme were mixed. The mass ratio is 10:2:0.2, and the complex enzyme is composed of laccase and lignin peroxidase in a mass ratio of 1.2:0.8; at 50°C, set the rotation speed to 200 rpm, stir and activate for 10 hours to obtain a fermentation raw material; S2-3: spread the fermentation raw material flat, add water, and the amount of water added is 1 times the amount of the fermentation raw material; add fermentation liquid, and the amount of fermentation liquid added accounts for 5wt% of the fermentation raw material; compost and ferment at 55°C for 10 days, constantly turning during the process to obtain decomposed material; sieve it using a sieve with an aperture of 8mm×8mm, dry it after sieving, and obtain decomposed corn straw.

[0069] Comparative Example 4: Based on Example 2, the binder was replaced with polyvinyl alcohol and modified flour in a mass ratio of 5:3; the rest was the same as Example 2.

[0070] Testing experiment: The seedling raising matrix trays prepared in Examples 1-2 and Comparative Examples 1-4 were tested for anti-destructive strength using a universal testing machine; 130 g of sprouted rice was sown in biomass seedling raising matrix boxes with corresponding specifications of 580 mm × 280 mm × 30 mm for cultivation. Samples were collected on the 20th day, and the cultivation capacity was evaluated based on the fresh weight of the aboveground part; the obtained data are shown in the following table:

[0071]

[0072] Conclusion: It can be seen from the data in the above table that the present application has prepared an integrated biomass seedling raising matrix box with good mechanical properties and seedling raising performance by limiting the process of specific decomposing corn straw and optimizing the ratio of undecomposed and decomposed corn straw. Among them, the comparison of the data of Example 2 and Example 1 shows that the mechanical strength and seedling raising performance of the biomass seedling raising matrix box can be further enhanced by adjusting the adhesive. The data of Comparative Examples 1 to 3 show the importance of the fiber length of undecomposed corn straw, the ratio of undecomposed corn straw to decomposed corn straw, and the decomposition process of decomposed corn straw. The data of Comparative Example 4 shows that the introduction of a specific modified polyvinyl alcohol composite can effectively improve the rice seedling raising performance and mechanical strength of the seedling raising matrix tray.

[0073] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

Claims

1. A method for preparing a biomass seedling raising matrix box, characterized in that: The following steps are involved: Step 1: (1) Cut and crush the corn straw, and sieve it through a sieve with an aperture of 4 mm × 4 mm. The unsieved part is used as the undecomposed corn straw; (2) Preparation of decomposed corn straw: S2-1: Add the undecomposed corn straw to a 1~1.5wt% citric acid solution, set the liquid-solid ratio to 10~12:1, pretreat at room temperature for 2~3 hours, sterilize, separate, and dry to obtain the straw raw material; S2-2: Add the undecomposed corn straw to the straw raw material. Adding wood vinegar with a pH of 5.5±0.2 and a complex enzyme, stirring and activating at 45-50°C at a rotation speed of 100-200 rpm for 8-10 hours to obtain a fermentation raw material; S2-3: Spreading the fermentation raw material flat, adding water, and adding a fermentation liquid; composting and fermenting at 50-60°C for 7-10 days, constantly turning the compost during the process, to obtain a decomposed material; sieving the compost through a sieve with an aperture of 8 mm×8 mm, and drying the sieved material to obtain a decomposed corn stalk; Step 2: (1) fully mix the undecomposed corn straw and the decomposed corn straw to obtain a mixture; add nutrient fertilizer and mix evenly; add dilute sulfuric acid to adjust the pH to 5-6 to obtain a matrix raw material; (2) add a binder to dissolve it in water, add other additives and mix evenly to obtain an additive; Step 3: fully mix the matrix raw materials and additives, and press them into shape to obtain a seedling raising matrix tray; Step 4: Cover the bottom of the seedling raising matrix tray with a plastic film to obtain a biomass seedling raising matrix box; During the preparation of the fermentation raw material, the mass ratio of the straw raw material, the wood vinegar, and the complex enzyme is 10-12:2:0.2; the complex enzyme includes laccase, lignin peroxidase, phosphoenolpyruvate carboxylase, and acetyl-CoA carboxylase in a mass ratio of 1:0.7:0.2:0.1; during the preparation of the decomposed material, the amount of water added is 1-1.2 times that of the fermentation raw material; the amount of the fermentation liquid added accounts for 4-5wt% of the fermentation raw material; the fermentation liquid includes a thermoviolet Streptomyces liquid, a gametoderma liquid, a thermophilic spore mold liquid, a Lactobacillus plantarum liquid, a Bacillus subtilis liquid, and a Corynebacterium glutamicum liquid in a mass ratio of 3:2:2:1.5:1:0.5; The binder comprises a polyvinyl alcohol compound and modified flour in a mass ratio of 5:3; The preparation process of the polyvinyl alcohol complex comprises the following steps: adding montmorillonite to water and uniformly dispersing the mixture through ultrasonication to obtain a 0.01-0.02 g / mL dispersion; adding 0.05-1 mol / L protocatechuic acid and stirring for 1-2 hours; adding ammonium molybdate and continuing stirring for 2-3 hours; adding catechol-based polyvinyl alcohol, heating the mixture to 80-85° C. and stirring for 1-2 hours, filtering, and drying to obtain the polyvinyl alcohol complex; wherein the raw materials of the polyvinyl alcohol complex comprise the following substances: by weight, 1-1.2 parts of montmorillonite, 0.2-0.3 parts of protocatechuic acid, 0.04-0.06 parts of ammonium molybdate, and 4-5 parts of catechol-based polyvinyl alcohol; The modified flour preparation process comprises the following steps: mixing succinic anhydride and diethylenetriamine at a molar ratio of 0.6-0.8:1, stirring at 50-55° C. for 1-2 hours, heating to 100-120° C. and stirring for 1-2 hours to obtain a branched product; adding the branched product to water and stirring uniformly to obtain a 5-8 wt% mixed solution; adjusting the pH to 5.2±0.3; adding aldehyde-modified flour, stirring at 60-65° C. for 10-20 minutes, centrifuging, and drying to obtain the modified flour; wherein the mass ratio of aldehyde-modified flour to branched product is 1:0.4-0.

5.

2. The method for preparing a biomass seedling raising matrix box according to claim 1, wherein: Raw materials of the seedling raising matrix tray The invention comprises the following ingredients: by weight, 40 to 48 parts of undecomposed corn straw, 52 to 60 parts of decomposed corn straw, 4 to 12 parts of nutrient fertilizer, 0.2 to 2 parts of adhesive, and 0.01 to 1 part of other added ingredients; The other added ingredients include one or more of trace elements and fungicides; the raw materials of the adhesive include one or two of polyvinyl alcohol and flour; the nutrient fertilizers include nitrogen fertilizer, phosphorus fertilizer and potassium sulfate, the nitrogen fertilizer includes one or two of ammonium sulfate and urea, and the phosphorus fertilizer includes one or more of superphosphate, monoammonium phosphate and diammonium phosphate.

3. The method for preparing a biomass seedling raising matrix box according to claim 1, wherein: The width of the plastic film and the bottom of the seedling raising matrix tray is 2-4 cm.

4. The method for preparing a biomass seedling raising matrix box according to claim 1, wherein: The process parameters of the compression molding are: temperature of 100-120° C., pressure of 12-15 MPa, and time of 100-110 s.

5. The biomass seedling raising matrix box prepared according to the method for preparing a biomass seedling raising matrix box according to any one of claims 1 to 4.

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