Rice seedling raising substrate based on chicken manure biogas residues as well as preparation method and seedling raising method of rice seedling raising substrate

Abstract

The invention belongs to the technical field of livestock and poultry manure utilization and rice seedling raising. The invention provides a rice seedling raising substrate based on chicken manure biogas residues. The rice seedling raising substrate comprises the following components in percentage by mass: 25-35% of chicken manure biogas residues, 45-50% of garden soil, 4-6% of peat soil, 8-12% of rice husk charcoal, 4-6% of vermiculite and 1-3% of a seedling strengthening agent. About half of the seedling raising substrate is garden soil which is wide in source and convenient to obtain, and the cost can be effectively reduced; meanwhile, the chicken manure biogas residues are subjected to resource utilization, so that rich nitrogen, phosphorus, potassium and organic matters in the chicken manure biogas residues are fully utilized, and the problem that the stress resistance of seedlings is reduced due to too high nutrients is avoided while nutrient supply is guaranteed. In addition, only a small amount of peat soil, vermiculite and rice husk charcoal are needed as structure adjusting components, and dependence on non-renewable resources is reduced. Moreover, the obtained seedling raising substrate is moderate in volume weight, good in water retention and air permeability, high in nutrient content, stable in structure and long in storage period.

Description

Technical Field

[0001] This invention relates to the fields of livestock and poultry manure utilization and rice seedling cultivation technology, and in particular to a rice seedling cultivation substrate based on chicken manure biogas residue, its preparation method, and seedling cultivation method. Background Technology

[0002] Rice is widely cultivated in my country, mainly distributed in the Northeast Plain, the middle and lower reaches of the Yangtze River Plain, and the Sichuan Basin. Rice seedling substrate refers to the nutrient soil that provides a habitat and basic nutrients for rice seedlings during their seedling stage. It should be breathable and water-retentive, with low bacterial and disease resistance, promoting healthy seedling growth. The seedling substrate is a crucial factor determining the subsequent growth and yield of rice; a good seedling substrate is beneficial for seedling root development and more suitable for mechanical transplanting.

[0003] Traditional rice seedling substrates are mostly homemade by farmers, using locally sourced farmland soil mixed with well-rotted manure or chemical fertilizers. These methods have several drawbacks. For example, the processes of soil extraction, composting, fermentation, sieving, and acidification are cumbersome and labor-intensive; the large-scale use of topsoil damages the soil's arable layer, leading to nutrient loss; if taken from cultivated fields, it may carry pathogens and weed seeds, and there is a risk of herbicide residue from the previous crop; the proportions and fermentation quality depend on individual experience, resulting in low standardization. In the long run, this will damage farmland and hinder sustainable development. Therefore, developing a new rice seedling substrate will provide more avenues for environmental protection and increased agricultural production.

[0004] Studies have shown that chickens do not fully digest and absorb their feed, with approximately 40% to 70% of nutrients being excreted in their feces. Therefore, chicken manure has the highest nutrient content among all poultry and livestock manures. my country's livestock industry produces a large amount of chicken manure annually. The traditional method for treating chicken manure is biogas fermentation, which uses microorganisms under anaerobic conditions to decompose the organic waste in chicken manure, producing biogas, biogas slurry, and biogas residue. While biogas residue is rich in nitrogen, phosphorus, potassium, and other nutrients, making it an excellent bio-fertilizer, its utilization faces numerous challenges. These include its large volume and significantly lower nutrient content per unit weight compared to chemical fertilizers; its slow-release nature, which cannot quickly meet the needs of crops during critical growth stages; the risk of heavy metal accumulation; the potential for slight decreases in soil pH and increase soil salinity with long-term, high-volume application; and the possibility of secondary anaerobic fermentation during accumulation of unstabilized biogas residue, producing flammable methane, which poses an explosion risk in confined spaces. Therefore, there is an urgent need to develop new biogas residue treatment technologies to improve its resource utilization efficiency, accelerate nutrient conversion, and promote the transformation of biogas residue from low-value waste into high-value agricultural resources.

[0005] For the reasons mentioned above, researching and developing a breathable and water-retaining seedling substrate based on chicken manure biogas residue, which is low in cost and can effectively provide nutrition and promote healthy growth of rice seedlings during the seedling stage, as well as its preparation and seedling raising methods, has become the key to promoting sustainable agricultural development. Summary of the Invention

[0006] The purpose of this invention is to provide a novel rice seedling substrate with moderate porosity, rich nutrients, and low cost and easy availability, which addresses the shortcomings of existing technologies. By innovatively adding chicken manure biogas residue, the problem of chicken manure biogas residue utilization is effectively solved, and the efficient synergy between resource utilization and rice seedling cultivation is achieved.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a rice seedling substrate based on chicken manure biogas residue, comprising the following components by mass percentage: Chicken manure biogas residue 25-35%, garden soil 45-50%, peat soil 4-6%, rice husk charcoal 8-12%, vermiculite 4-6%, seedling strengthening agent 1-3%.

[0008] Preferably, the chicken manure biogas residue is chicken manure biogas residue obtained through composting treatment; The seedling strengthening agent is composed of pesticide active ingredients and plant growth regulators; wherein the pesticide active ingredients are metalaxyl and / or phoxim; and the plant growth regulator is paclobutrazol.

[0009] The present invention also provides a method for preparing the rice seedling substrate, comprising the following steps: 1) Compost chicken manure and biogas residue; 2) Dry the chicken manure residue and garden soil after composting; 3) Mix the dried chicken manure biogas residue, garden soil, peat moss, rice husk charcoal, vermiculite and seedling strengthening agent to obtain rice seedling substrate.

[0010] Preferably, the composting process in step 1) is aerobic composting; The composting process is carried out at a temperature of 55-65°C for 15-30 days, and the moisture content of the material is 50-60%.

[0011] Preferably, the drying temperature in step 2) is 20~30℃, the drying time is 3~4 days, and the leaves are turned over every 2~4 hours during the drying process.

[0012] The present invention also provides a method for raising rice seedlings using the aforementioned rice seedling substrate, comprising the following steps: S1. Rice seeds are subjected to sun-drying, soaking, and germination treatment; S2. Add a potassium nitrate solution with a concentration of 0.4~0.6mol / L to the rice seedling substrate and mix. At the same time, add water to adjust the moisture content of the substrate so that it can be formed into a ball when squeezed, does not fall apart when handled, and does not drip water. Adjust the pH to 5~6.5 with a concentration of 1~3mol / L dilute sulfuric acid and then spread it in the seedling tray with a thickness of 1.4~1.6cm. S3. When the germinated seeds weigh 400-600g per tray of seedling substrate, the corresponding sowing amount is 110-130g. Sow the seeds evenly on the surface of the seedling substrate and cover them with soil. S4. Darken the seedling trays after sowing; S5. After emergence, manage water and temperature until the seedlings reach the transplanting standard; among them, before the seedlings reach the 1-leaf-1-heart stage, control the ambient temperature to 20-25℃ during the day and ≥15℃ at night, and adjust ventilation when the temperature is too high; after the seedlings grow to the 2-leaf-1-heart stage, harden them off to keep the day-night temperature difference within 10℃; during the seedling raising process, spray with hymexazol and sodium dichloroisocyanurate every 7 days; when the seedlings grow to the 3-leaf-1-heart stage or the plant height is ≥15cm, transplant them.

[0013] Preferably, the soaking process in step S1 includes salt water selection, disinfection treatment, and soaking in clean water. The mass concentration of the brine is 8-12%, and the brine selection time is 5-10 minutes. The temperature for soaking the seeds in clean water is 30~35℃, and the time is 24~48h. The water is changed every 12 hours during the soaking process.

[0014] Preferably, the disinfection treatment in step S1 is carried out using a bactericide solution; the bactericide solution is a solution obtained by diluting imazalil emulsifiable concentrate with an effective ingredient content of 20-30% by volume 2000-3000 times. The disinfection process takes 12 to 24 hours and is carried out at a temperature of 15 to 20°C.

[0015] Preferably, the germination treatment in step S1 is carried out at 30~35℃ until the seed sprouts and the sprout length is ≤0.5cm. The temperature for the darkening process in step S4 is 25~40℃, and the darkening time is 1~2 days.

[0016] Preferably, in step S5, the substrate moisture content is adjusted by spray irrigation in the early stage after seedling emergence, so that the substrate moisture content is maintained at 60~70%; the spray irrigation is carried out once in the morning and once in the evening every day, and the temperature of the irrigation water is 15~25℃.

[0017] The beneficial effects of this invention include the following: 1) The proportion of chicken manure biogas residue in the rice seedling substrate of the present invention is as high as 25-35%. The dried chicken manure biogas residue has a small mass but a large actual volume. The addition of 25-35% chicken manure biogas residue can greatly reduce environmental pollution and turn waste into treasure.

[0018] 2) Compared with common commercial substrates, the rice seedling substrate of the present invention can increase the height and stem base of seedlings, promote root development and increase white roots, and also significantly improve the leaf age and leaf area of ​​seedlings, resulting in green leaves, which is conducive to rapid greening and tillering after transplanting.

[0019] 3) The preparation process of the rice seedling substrate described in this invention is simple. It only requires mixing the components in proportion. Large-scale production can save labor costs.

[0020] 4) The rice seedling substrate described in this invention consists mostly of livestock and poultry manure and garden soil. It has a large yield and low price. Only a small amount of peat soil, rice husk charcoal, vermiculite and seedling strengthening agent need to be purchased in addition, which saves costs to the maximum extent. Attached Figure Description

[0021] Figure 1 The images show the growth status of rice seedlings under different substrate conditions on day 13 and day 25; where A is the growth status of rice seedlings on day 13 and B is the growth status of rice seedlings on day 25. Figure 2 A comparison of rice seedling height on day 13 and day 25 under different substrate conditions; Figure 3 Comparison of stem base thickness of rice seedlings on day 13 and day 25 under different substrate conditions; Figure 4 A comparison of leaf age of rice seedlings on day 13 and day 25 under different substrate conditions; Figure 5 A comparison of leaf area of ​​rice seedlings on day 13 and day 25 under different substrate conditions; Figure 6 Comparison of the longest roots of rice seedlings on day 13 and day 25 under different substrate conditions; Figure 7 A comparison of the number of rice seedling roots on day 13 and day 25 under different substrate conditions; Figure 8 A comparison of the dry weight of 100 rice seedlings on day 13 and day 25 under different substrate conditions; Figure 9 A comparison of the seedling vigor index of rice seedlings on day 13 and day 25 under different substrate conditions; Figure 10 The graph shows the chlorophyll content of rice seedlings under different substrate conditions on day 25. Detailed Implementation

[0022] This invention provides a rice seedling substrate based on chicken manure biogas residue, comprising the following components by mass percentage: Chicken manure biogas residue 25-35%, garden soil 45-50%, peat soil 4-6%, rice husk charcoal 8-12%, vermiculite 4-6%, seedling strengthening agent 1-3%.

[0023] The rice seedling substrate based on chicken manure biogas residue described in this invention contains 25-35% by weight. Chicken manure biogas residue, preferably 26-34%, more preferably 28-32%, and even more preferably 30%.

[0024] In this invention, the chicken manure biogas residue is preferably obtained through composting.

[0025] In this invention, the chicken manure biogas residue is rich in nitrogen, phosphorus, potassium and organic matter, and contains fewer pathogens.

[0026] The rice seedling substrate based on chicken manure biogas residue of the present invention contains 45-50% garden soil by mass, preferably 46-49%, more preferably 47-49%, and even more preferably 48%.

[0027] In this invention, the garden soil is taken from natural fields, is less affected by the environment, and is suitable for crop growth conditions.

[0028] The rice seedling substrate based on chicken manure biogas residue of the present invention contains 4-6% peat soil by mass, preferably 4.5-5.5%, more preferably 4.8-5.2%, and more preferably 5%.

[0029] In this invention, the peat soil is rich in humus, mainly composed of humic acid, has good exchange properties, and suitable acidity. It can be used as a soil amendment material with only light processing.

[0030] The rice seedling substrate based on chicken manure biogas residue of the present invention contains 8-12% rice husk charcoal by mass, preferably 9-11%, more preferably 9.5-10.5%, and more preferably 10%.

[0031] In this invention, the rice husk charcoal is rich in nutrients, free of pathogens, and rich in potassium, which can make the soil loose, breathable, and darker in color.

[0032] The rice seedling substrate based on chicken manure biogas residue of the present invention contains 4-6% vermiculite by mass, preferably 4.5-5.5%, more preferably 4.8-5.2%, and even more preferably 5%.

[0033] In this invention, the vermiculite has good cation exchange and adsorption properties, which can improve soil structure, retain water and moisture, improve soil permeability and water content, and turn acidic soil into neutral soil.

[0034] The rice seedling substrate based on chicken manure biogas residue of the present invention contains 1-3% by weight of seedling strengthening agent, preferably 1.5-2.5%, more preferably 1.8-2.2%, and more preferably 2%.

[0035] In this invention, the seedling strengthening agent is preferably composed of pesticide active ingredients and plant growth regulators; wherein, the pesticide active ingredients are preferably metalaxyl and / or phoxim; and the plant growth regulator is preferably paclobutrazol.

[0036] The present invention also provides a method for preparing the rice seedling substrate, comprising the following steps: 1) Compost chicken manure and biogas residue; 2) Dry the composted chicken manure residue and garden soil in the sun; 3) Mix the dried chicken manure biogas residue, garden soil, peat moss, rice husk charcoal, vermiculite and seedling strengthening agent to obtain rice seedling substrate.

[0037] In this invention, the composting treatment in step 1) is preferably aerobic composting; The composting treatment temperature is preferably 55~65℃, more preferably 58~62℃, and even more preferably 60℃; the time is preferably 15~30d, more preferably 20~25d, and even more preferably 22d; the moisture content of the material is preferably 50~60%, more preferably 54~56%, and even more preferably 55%; and the pH value is preferably 6.5~8.0, and even more preferably 7~7.5.

[0038] In this invention, during the composting process described in step 1), ventilation is preferably performed simultaneously; the ventilation method is preferably forced ventilation; the intensity of the forced ventilation is preferably 0.2~0.5 L / (min·kg) chicken manure biogas residue, more preferably 0.3~0.4 L / (min·kg) chicken manure biogas residue, and even more preferably 0.35 L / (min·kg) chicken manure biogas residue; the duration of the forced ventilation is preferably 15~30 min / d, more preferably 20~25 min / d, and even more preferably 22 min / d.

[0039] In this invention, the temperature of the drying process in step 2) is preferably 20~30℃, more preferably 24~26℃, and even more preferably 25℃; the drying time is preferably 3~4 days, more preferably 3.5 days; and during the drying process, it is preferably turned over once every 2~4 hours, more preferably once every 3 hours.

[0040] The present invention also provides a method for raising rice seedlings using the aforementioned rice seedling substrate, comprising the following steps: S1. Rice seeds are subjected to sun-drying, soaking, and germination treatment; S2. Add a potassium nitrate solution with a concentration of 0.4~0.6mol / L, preferably 0.5mol / L, to the rice seedling substrate and mix. At the same time, add water to adjust the moisture content of the substrate so that it can be formed into a ball when squeezed, does not crumble when handled, and does not drip water. Adjust the pH to 5~6.5 with a dilute sulfuric acid solution with a concentration of 1~3mol / L, preferably 2mol / L. The pH is preferably 5.5. After adjusting the pH, spread the substrate in the seedling tray with a thickness of 1.4~1.6cm, preferably 1.5cm. S3. When the germinated seeds weigh 400-600g per tray of seedling substrate, the corresponding sowing amount is 110-130g. Sow the seeds evenly on the surface of the seedling substrate and cover them with soil. S4. Darken the seedling trays after sowing; S5. After emergence, manage water and temperature until the seedlings reach the transplanting standard; among them, before the seedlings reach the 1-leaf-1-heart stage, control the ambient temperature to 20-25℃ during the day and ≥15℃ at night, and adjust ventilation when the temperature is too high; after the seedlings grow to the 2-leaf-1-heart stage, harden them off to keep the day-night temperature difference within 10℃; during the seedling raising process, spray with hymexazol and sodium dichloroisocyanurate every 7 days; when the seedlings grow to the 3-leaf-1-heart stage or the plant height is ≥15cm, transplant them.

[0041] In this invention, the soaking of seeds in step S1 preferably includes salt water selection, disinfection treatment, and soaking in clean water; The preferred mass concentration of the brine is 8-12%, more preferably 9-11%, and even more preferably 10%; the preferred brine selection time is 5-10 min, more preferably 6-8 min, and even more preferably 7 min. The preferred temperature for soaking seeds in clean water is 30-35℃, more preferably 32-34℃, and even more preferably 33℃; the preferred time is 24-48h, more preferably 30-40h, and even more preferably 35h, and the water is preferably changed every 12 hours during the soaking process.

[0042] In this invention, the disinfection treatment in step S1 is preferably carried out using a bactericide solution; the bactericide solution is preferably a solution obtained by diluting prochloraz emulsifiable concentrate with an effective ingredient content of 20-30% by volume 2000-3000 times, and more preferably a solution obtained by diluting prochloraz emulsifiable concentrate with an effective ingredient content of 25% by volume 2500 times; The disinfection treatment time is preferably 12-24 hours, more preferably 16-20 hours, and even more preferably 18 hours; the disinfection treatment temperature is preferably 15-20°C, more preferably 16-18°C, and even more preferably 17°C.

[0043] In this invention, the germination treatment in step S1 is preferably carried out at 30~35℃, more preferably at 34℃, preferably until the seed sprouts and shows white tips, and the sprout length is preferably ≤0.5cm, more preferably ≤0.4cm.

[0044] In this invention, the amount of potassium nitrate solution added in step S2 is preferably 15-25 mL per kilogram of rice seedling substrate, and more preferably 20 mL per kilogram of rice seedling substrate.

[0045] In this invention, the temperature of the darkening treatment in step S4 is preferably 25~40℃, more preferably 30~35℃, and even more preferably 32℃; the time of the darkening treatment is preferably 1~2 days, and even more preferably 1.5 days.

[0046] In this invention, in step S5, the substrate moisture content is preferably adjusted by spray irrigation in the early stage after seedling emergence, so that the substrate moisture content is preferably 60-70%, more preferably 65%; the spray irrigation is preferably carried out once in the morning and once in the evening every day, and the temperature of the irrigation water is preferably 15-25℃, more preferably 18-22℃, and more preferably 20℃.

[0047] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0048] The chicken manure biogas residue and garden soil used in the embodiments and comparative examples of this invention were all obtained from Chengdu Hongji Borun Environmental Protection Technology Co., Ltd. The chicken manure biogas residue was used after composting treatment; the peat soil was household gardening peat soil, purchased from Stanley Hongxiu Specialty Store, brand name Stanley, and its main component was organic peat; the rice husk charcoal was garden rice husk charcoal, purchased from Cailezhi Flagship Store, brand name Cailezhi, and its main component was carbonized rice husk; the vermiculite was high-quality vermiculite, purchased from Guanglang Flagship Store, brand name Guanglang, and its product specifications were 1~3mm.

[0049] Example 1: The rice variety "Rongxiangyou 794" was selected as the experimental material. The rice seeds were sun-dried for 3 days in a sunny weather (temperature 25℃), spreading them evenly into a 3cm thick layer and turning them every 3 hours. Then, the seeds were placed in a 10% saline solution for selection for 8 minutes, removing floating seeds and rinsing them three times with clean water. Next, the salt-selected seeds were disinfected in a fungicide solution (25% prochloraz emulsifiable concentrate diluted 3000 times by volume) for 20 hours at 20℃, and then rinsed thoroughly with clean water. Finally, the seeds were soaked in clean water at 34℃ for 30 hours, with the water changed every 12 hours. After soaking, the seeds were germinated at 34℃ until the sprouts emerged and reached a length of 0.4cm.

[0050] Chicken manure biogas residue was subjected to aerobic composting at a temperature of 55℃ for 30 days. The moisture content of the material was 50%, and the pH value was 6.5. Forced ventilation was carried out simultaneously during the composting process at an intensity of 0.2 L / (min·kg) of chicken manure biogas residue for 30 min / day. The composted chicken manure biogas residue and garden soil were then dried at 25℃ for 3 days, and turned over every 3 hours during the drying process.

[0051] Based on 500g of seedling substrate per tray, 4 trays are made, with some reserved for covering soil, for a total of 3000g per tray.

[0052] Weigh out the following components by weight percentage: 30% chicken manure biogas residue, 48% garden soil, 5% peat moss, 10% rice husk charcoal, 5% vermiculite, and 2% seedling strengthener (composed of metalaxyl, phoxim, and paclobutrazol in a mass ratio of 20:1:15). Mix all components thoroughly. Add 60 mL of 0.5 mol / L potassium nitrate solution to the mixture and stir. Simultaneously, add an appropriate amount of water to adjust the substrate moisture content to 60%, ensuring the substrate can be formed into a clump when squeezed but does not crumble when released and does not drip water. Then, adjust the substrate pH to 5.5 using 2 mol / L dilute sulfuric acid. Spread the prepared substrate in seedling trays (60cm×30cm×3cm) to a thickness of 1.5cm.

[0053] After the substrate is laid out, sow 120g of seeds in each tray and cover them with soil using the seedling substrate, ensuring the seeds are not visible. After sowing, stack the trays, wrap them with two layers of non-woven fabric, and then perform a darkening treatment at 30℃ for two days. After germination, transfer the seedling trays to a greenhouse for continued seedling cultivation.

[0054] After emergence, water and temperature management are implemented. In the early post-emergence period, the substrate moisture content is regulated by sprinkler irrigation, maintaining it at 60%. Sprinkler irrigation is carried out twice daily, morning and evening, with the irrigation water temperature at 15℃. Before the seedlings reach the one-leaf-one-heart stage, the ambient temperature is controlled at 25℃ during the day and 20℃ at night, with ventilation adjusted when the temperature is too high. Once the seedlings reach the two-leaf-one-heart stage, hardening-off treatment is performed to maintain a day-night temperature difference within 10℃. During the seedling stage, hymexazol and sodium dichloroisocyanurate are sprayed every 7 days for disease control. Transplanting is carried out when the seedlings reach the three-leaf-one-heart stage or a plant height of 15cm or more. This embodiment corresponds to... Figures 1-10 The “30%CDO” group.

[0055] Based on actual calculations, the bulk density of chicken manure biogas residue in the seedling substrate prepared in this embodiment is approximately 0.45 g / cm³. 3 The total nitrogen content is approximately 23.3 mg / g, the total phosphorus content is approximately 130 mg / g, the total potassium content is approximately 7.78 mg / g, and the total organic matter content is approximately 26.88%.

[0056] Example 2: The rice variety "Rongxiangyou 794" was selected as the experimental material. The rice seeds were sun-dried for 3 days in a sunny weather (temperature 20℃), spreading them evenly into a 4cm thick layer and turning them every 3 hours. Then, the seeds were placed in an 8% saline solution for 10 minutes for selection, removing floating seeds and rinsing them three times with clean water. Next, the salt-selected seeds were disinfected in a fungicide solution (2000 times volume dilution of 20% prochloraz emulsifiable concentrate) for 24 hours at 15℃, followed by rinsing with clean water. Finally, the seeds were soaked in clean water at 30℃ for 48 hours, with the water changed every 12 hours. After soaking, the seeds were germinated at 30℃ until the sprouts emerged and reached a length of 0.5cm.

[0057] Chicken manure biogas residue was subjected to aerobic composting at a temperature of 60℃ for 20 days. The moisture content of the material was 55%, and the pH value was 7. During the composting process, forced ventilation was carried out at an intensity of 0.4 L / (min·kg) of chicken manure biogas residue for 20 min / day. The composted chicken manure biogas residue and garden soil were then dried at 20℃ for 4 days, and turned over every 4 hours during the drying process.

[0058] Based on 400g of seedling substrate per tray, 4 trays are made, with some reserved for covering soil, for a total of 2500g per tray.

[0059] Weigh out the following components by weight percentage: 25% chicken manure biogas residue, 50% garden soil, 4% peat moss, 12% rice husk charcoal, 6% vermiculite, and 3% seedling strengthener (the seedling strengthener consists of metalaxyl, phoxim, and paclobutrazol in a mass ratio of 20:1:15). Mix all components thoroughly. Add 62.5 mL of 0.4 mol / L potassium nitrate solution to the mixture and stir. Simultaneously, add an appropriate amount of water to adjust the substrate moisture content to 55%, ensuring the substrate can be formed into a clump when squeezed but does not crumble when released and does not drip water. Then, adjust the substrate pH to 6.5 using 1 mol / L dilute sulfuric acid. Spread the prepared substrate in seedling trays (60cm×30cm×3cm) to a thickness of 1.6cm.

[0060] After the substrate is laid out, sow 110g of seeds in each tray and cover them with soil using the seedling substrate, ensuring the seeds are not visible. After sowing, stack the trays, wrap them with two layers of non-woven fabric, and then perform a darkening treatment at 25℃ for 1.5 days. After germination, transfer the seedling trays to a greenhouse for continued seedling cultivation.

[0061] After emergence, water and temperature management are crucial. In the early post-emergence period, the substrate moisture content is regulated by sprinkler irrigation, maintaining it at 65%. Sprinkler irrigation is performed twice daily, morning and evening, with the irrigation water temperature at 20℃. From emergence to the stage of one leaf and one bud, the ambient temperature is controlled at 20℃ during the day and 15℃ at night, with ventilation adjusted when temperatures are too high. Once the seedlings reach the two-leaf and one-bud stage, hardening-off treatment is implemented to maintain a day-night temperature difference within 10℃. During the seedling stage, hymexazol and sodium dichloroisocyanurate are sprayed every 7 days for disease control. Transplanting is performed when the seedlings reach the three-leaf and one-bud stage or a plant height of 15cm or more.

[0062] Example 3: The rice variety "Rongxiangyou 794" was selected as the experimental material. The rice seeds were sun-dried for 3 days in a sunny weather (30℃), spreading them evenly into a thin layer of 3.5cm thickness and turning them over every 3 hours. Then, the seeds were placed in a 12% saline solution for selection for 5 minutes, removing floating seeds and rinsing them four times with clean water. Next, the salt-selected seeds were disinfected in a fungicide solution (30% prochloraz emulsifiable concentrate diluted 2500 times by volume) for 12 hours at 18℃, and then rinsed thoroughly with clean water. Finally, the seeds were soaked in clean water at 35℃ for 24 hours, with the water changed every 12 hours. After soaking, the seeds were germinated at 35℃ until the sprouts emerged and reached a length of 0.5cm.

[0063] Chicken manure biogas residue was subjected to aerobic composting at a temperature of 65℃ for 15 days, with a pH of 8. Forced ventilation was also carried out during the composting process at an intensity of 0.5 L / (min·kg) of chicken manure biogas residue for 15 min / day. The moisture content of the material was 60%. The composted chicken manure biogas residue and garden soil were then sun-dried at 30℃ for 3.5 days, and turned over every 2 hours during the sun-drying process.

[0064] Based on 600g of seedling substrate per tray, 4 trays are made, with some reserved for covering soil, for a total of 3500g per tray.

[0065] Weigh out the following components by weight percentage: 35% chicken manure biogas residue, 45% garden soil, 6% peat moss, 8% rice husk charcoal, 4% vermiculite, and 2% seedling strengthener (the seedling strengthener consists of metalaxyl, phoxim, and paclobutrazol in a mass ratio of 20:1:15). Mix all components thoroughly. Add 52.5 mL of 0.6 mol / L potassium nitrate solution to the mixture and stir. Simultaneously, add an appropriate amount of water to adjust the substrate moisture content to 65%, ensuring the substrate can be formed into a clump when squeezed but does not crumble when released and does not drip water. Then, adjust the substrate pH to 5 using 3 mol / L dilute sulfuric acid. Spread the prepared substrate in seedling trays (60cm×30cm×3cm) to a thickness of 1.4cm.

[0066] After the substrate is laid out, sow 130g of seeds in each tray and cover them with soil using the seedling substrate, ensuring the seeds are not visible. After sowing, stack the trays, wrap them with two layers of non-woven fabric, and then perform a darkening treatment at 40℃ for one day. After germination, transfer the seedling trays to a greenhouse for continued seedling cultivation.

[0067] After emergence, water and temperature management are implemented. In the early emergence stage, the substrate moisture content is regulated by sprinkler irrigation, maintaining it at 70%. Sprinkler irrigation is carried out twice daily, morning and evening, with the irrigation water temperature at 25℃. Before the seedlings reach the stage of one leaf and one bud, the ambient temperature is controlled at 22℃ during the day and 16℃ at night, with ventilation adjusted when the temperature is too high. Once the seedlings reach the two-leaf and one-bud stage, hardening-off treatment is performed to maintain a day-night temperature difference within 10℃. During the seedling stage, hymexazol and sodium dichloroisocyanurate are sprayed every 7 days for disease control. Transplanting is carried out when the seedlings reach the three-leaf and one-bud stage or the plant height reaches 15cm or more.

[0068] Comparative Example 1: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 70%, garden soil is 28%, and seedling strengthening agent is 2%. Peat moss, rice husk charcoal, and vermiculite are not added. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10The "70%CD" group.

[0069] Comparative Example 2: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 50%, garden soil is 48%, and seedling strengthening agent is 2%. Peat moss, rice husk charcoal, and vermiculite are not added. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The "50%CD" group.

[0070] Comparative Example 3: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 30%, garden soil is 68%, and seedling strengthening agent is 2%. Peat moss, rice husk charcoal, and vermiculite are not added. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The "30%CD" group.

[0071] Comparative Example 4: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 70%, garden soil is 8%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The "70%CDO" group.

[0072] Comparative Example 5: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 50%, garden soil is 28%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The "50%CDO" group.

[0073] Comparative Example 6: The difference between this comparative example and Example 1 is that the mass percentage of corn straw biogas residue (prepared by aerobic composting of corn straw biogas residue according to the composting method and parameters of chicken manure biogas residue in Example 1) in the rice seedling substrate is 70%, garden soil is 8%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The "70%SDO" group.

[0074] Comparative Example 7: The difference between this comparative example and Example 1 is that the mass percentage of corn straw biogas residue (prepared by aerobic composting of corn straw biogas residue according to the composting method and parameters of chicken manure biogas residue in Example 1) in the rice seedling substrate is 50%, garden soil is 28%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The "50%SDO" group.

[0075] Comparative Example 8: The difference between this comparative example and Example 1 is that the mass percentage of corn straw biogas residue (prepared by aerobic composting of corn straw biogas residue according to the composting method and parameters of chicken manure biogas residue in Example 1) in the rice seedling substrate is 30%, garden soil is 48%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The “30%SDO” group.

[0076] Comparative Example 9: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 23%, corn straw biogas residue (prepared by aerobic composting of corn straw biogas residue according to the composting method and parameters of chicken manure biogas residue in Example 1) is 47%, garden soil is 8%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The “70%C1S2” group.

[0077] Comparative Example 10: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 17%, corn straw biogas residue (prepared by aerobic composting of corn straw biogas residue according to the composting method and parameters of chicken manure biogas residue in Example 1) is 33%, garden soil is 28%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The “50%C1S2” group.

[0078] Comparative Example 11: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 10%, corn straw biogas residue (prepared by aerobic composting of corn straw biogas residue according to the composting method and parameters of chicken manure biogas residue in Example 1) is 20%, garden soil is 48%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The “30%C1S2” group.

[0079] Comparative Example 12: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 47%, corn straw biogas residue (prepared by aerobic composting of corn straw biogas residue according to the composting method and parameters of chicken manure biogas residue in Example 1) is 23%, garden soil is 8%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The “70%C2S1” group.

[0080] Comparative Example 13: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 33%, corn straw biogas residue (prepared by aerobic composting of corn straw biogas residue according to the composting method and parameters of chicken manure biogas residue in Example 1) is 17%, garden soil is 28%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to Figures 1-10 The “50%C2S1” group.

[0081] Comparative Example 14: The difference between this comparative example and Example 1 is that the mass percentage of chicken manure biogas residue in the rice seedling substrate is 20%, corn straw biogas residue (prepared by aerobic composting of corn straw biogas residue according to the composting method and parameters of chicken manure biogas residue in Example 1) is 10%, garden soil is 48%, peat moss is 5%, rice husk charcoal is 10%, vermiculite is 5%, and seedling strengthening agent is 2%. The remaining preparation methods and seedling raising steps are the same as in Example 1. This comparative example corresponds to... Figures 1-10 The “30%C2S1” group.

[0082] Comparative Example 15: The difference between this comparative example and Example 1 is that the seedling substrate was replaced with an equal mass of Product 1 (purchased from Kangbaohe Rice Seedling Substrate). This comparative example corresponds to... Figures 1-10 Group "C1" in the text.

[0083] Comparative Example 16: The difference between this comparative example and Example 1 is that the seedling substrate was replaced with an equal mass of Product 2 (purchased from the rice cultivation base in Jiushan Village, Linqiong Street, Qionglai City, Chengdu). This comparative example corresponds to... Figures 1-10 Group "C2" in the text.

[0084] On the 13th and 25th day after sowing, 50 seedlings from Example 1 and Comparative Examples 1-16 were taken as test samples. Three representative plants were randomly selected from these samples for relevant index measurements, and the results were used as characterization data for this treatment.

[0085] Seedling height is measured with a ruler, stem base diameter is measured with a vernier caliper, leaf age and leaf area are measured with a ruler and the leaf length and width are calculated, root length is measured with a ruler, total number of roots is estimated visually, dry weight of 100 seedlings is obtained by drying 100 seedlings and weighing them, and seedling vigor index is determined by (stem base diameter × dry weight of 100 seedlings) / seedling height. The method for determining chlorophyll content is as follows: Take fresh, clean rice leaves, weigh 0.2g, cut them into small pieces in a mortar, add 2g of quartz sand and 6mL of 95% ethanol solution, grind into a homogenate, continue to add 95% ethanol solution and grind until the tissue turns white, let stand for 15 minutes, take a clean filter paper and place it on the inner wall of the funnel, moisten it with anhydrous ethanol, place a glass rod at the third layer of filter paper, guide the homogenate along the glass rod, filter it into a 50mL brown volumetric flask, wash the mortar and glass rod with anhydrous ethanol and transfer them together, finally make up to 50mL with 95% ethanol solution, repeat twice.

[0086] Take a clean cuvette, rinse it three times with the test solution, and then pour the solution into the cuvette. Place a 95% ethanol solution in the first cuvette as a blank control. Then measure the absorbance at wavelengths of 663 nm and 645 nm. Each measurement should be repeated three times at different wavelengths, and the average value should be taken.

[0087] The chlorophyll content can be calculated using the following formula.

[0088] Chlorophyll a content = (12.7D) 663nm -2.69D 645nm )×(V / 1000×m; Chlorophyll b content = (22.9D) 663nm -4.68D 645nm )×(V / 1000×m) Total chlorophyll = (20.21D) 663nm -8.02D 645nm )×(V / 1000×m) In the formula: D 663nm D 645nmThe absorbance values ​​are 663 nm and 645 nm, respectively; V is the volume of the test liquid (mL); and m is the fresh weight of the leaf (g).

[0089] The growth status of seedlings in each treatment group and the test results of the substrate physicochemical properties are as follows: Figures 1-10 As shown in the figure. The growth status of seedlings in different treatment groups on day 13 and day 25 is shown in the figure below. Figure 1 As shown. By Figure 1 It can be concluded that the substrate ratio of the 30% CDO group is the optimal substrate for rice seedling raising.

[0090] The comparison charts of plant height, stem base diameter, leaf age, leaf area, longest root, and number of roots of seedlings in different treatment groups on day 13 and day 25 are shown below. Figures 2-7 As shown. By Figures 2-7 It can be seen that: In terms of plant height, at 25 days, the 50%CDO, 30%CDO, 70%C2S1, and 30%C2S1 treatment groups were all significantly taller than the commercial group, with significant differences. Among them, the 30%CDO treatment group had the tallest plant height, which was 33.03% taller than the best commercial group, C2. In terms of stem base diameter, at 25 days, the 70%CD, 50%CD, 50%CDO, and 30%CDO treatment groups were all significantly taller than the commercial group, with significant differences. Among them, the 50%CDO treatment group had the thickest stem base diameter, which was significantly larger than the best commercial group, C2. The commercial group C2 had a 30.21% higher leaf age. Regarding leaf age, at 25 days, 50%CD and 30%C1S2 had the highest and significantly higher leaf age than commercial group C2, by 14.52%, and most were also higher than commercial group C1. In terms of leaf area, most treatment groups had higher leaf area than commercial group C1. The 50%CD, 70%CDO, 50%CDO, 30%CDO, 30%C1S2, and 70%C2S1 treatments were significantly higher than C2, with the highest being 30%CDO, which was 98.51% higher than C2. Overall, 50%CD and 30%C1S2 had older leaf ages but lower leaf areas than 30%CDO; 30%CDO had the largest leaf area, with a leaf age slightly younger than 50%CD and 30%C1S2, indicating that 30%CDO had better leaf conditions. Regarding the longest roots, at 25 days, the 30%CDO, 70%SDO, and 30%C1S2 treatments were significantly longer than the C2 treatment group, with the longest, 70%SDO, being 22.63% longer than C2. Regarding the number of roots, at 25 days, the 70%CD, 50%CDO, and 30%CDO treatments were significantly longer than the commercial group C2, with the 50%CDO treatment having the most roots, being 27.87% longer than C2. Considering both the longest and most roots, the 30%CDO treatment showed the best root system. Based on these results, the optimal treatment group was the 30%CDO group, under which rice seedlings exhibited the highest plant height, the best leaf and root system condition, and a relatively thick stem base.

[0091] The comparison of the dry weight per 100 seedlings in different treatment groups on day 13 and day 25 is shown in the figure below. Figure 8 As shown. By Figure 8It can be seen that the dry weight of 100 plants in all 17 experimental groups increased significantly from 13 to 25 days after sowing. Most treatment groups had a dry weight of 100 plants exceeding that of commercial group C1 at 25 days, while only 30% of CD groups had a dry weight of less than that of commercial group C1. In addition, most treatment groups had a dry weight of 100 plants less than that of commercial group C2 at 25 days.

[0092] The comparison of seedling vigor index on day 13 and day 25 for different treatment groups is shown in the figure below. Figure 9 As shown. By Figure 9 It can be seen that, based on the seedling vigor index, the seedling vigor index of most experimental groups showed an increasing trend from 13 to 25 days after sowing, while the index of 30% SDO and 50% C2S1 decreased instead of increasing, indicating that these two substrates could not continuously provide the nutrients and environment required for seedling growth. At 25 days, the seedling vigor index of the 30% CDO treatment group was the highest, 50.12% higher than that of the C2 commercial group. This indicates that the 30% CDO treatment group had a well-developed root system, strong resistance, and a higher survival rate after transplanting.

[0093] The chlorophyll content of seedlings in different treatment groups on day 25 is shown in the figure. Figure 10 As shown. By Figure 10 It can be seen that the chlorophyll content was uneven among the experimental groups. For rice seedlings to have a suitable and balanced chlorophyll content and green leaf color, a range of 1.5-2.5 mg / gFW (fresh weight) is generally appropriate. The chlorophyll content of the two commercial groups fell within this range, which is considered suitable. The chlorophyll content of the 50% CDO, 30% CDO, 70% SDO, 50% SDO, 30% SDO, 30% C1S2, and 70% C2S1 treatment groups was relatively suitable.

[0094] In summary, the seedlings grown using the 30% CDO substrate meet the optimal transplanting conditions in terms of plant height and leaf age, have complex root systems and strong root cohesion, accumulate more dry matter, are more resistant to adverse conditions, and have a higher survival rate and tillering ability; their leaves are green, which is beneficial for post-transplanting greening.

[0095] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A rice seedling substrate based on chicken manure biogas residue, characterized in that, Components comprising the following mass percentages: Chicken manure biogas residue 25-35%, garden soil 45-50%, peat soil 4-6%, rice husk charcoal 8-12%, vermiculite 4-6%, seedling strengthening agent 1-3%.

2. The rice seedling substrate according to claim 1, characterized in that, The chicken manure biogas residue is chicken manure biogas residue obtained through composting. The seedling strengthening agent is composed of pesticide active ingredients and plant growth regulators; wherein the pesticide active ingredients are metalaxyl and / or phoxim; and the plant growth regulator is paclobutrazol.

3. The method for preparing the rice seedling substrate according to claim 1 or 2, characterized in that, Includes the following steps: 1) Compost chicken manure and biogas residue; 2) Dry the chicken manure residue and garden soil after composting; 3) Mix the dried chicken manure biogas residue, garden soil, peat moss, rice husk charcoal, vermiculite and seedling strengthening agent to obtain rice seedling substrate.

4. The preparation method according to claim 3, characterized in that, Step 1) describes an aerobic composting process. The composting process is carried out at a temperature of 55-65°C for 15-30 days, and the moisture content of the material is 50-60%.

5. The preparation method according to claim 4, characterized in that, Step 2) The drying temperature is 20~30℃, the drying time is 3~4 days, and the leaves are turned over every 2~4 hours during the drying process.

6. A method for raising rice seedlings using the rice seedling substrate according to claim 1 or 2, characterized in that, Includes the following steps: S1. Rice seeds are subjected to sun-drying, soaking, and germination treatment; S2. Add a potassium nitrate solution with a concentration of 0.4~0.6mol / L to the rice seedling substrate and mix. At the same time, add water to adjust the moisture content of the substrate so that it can be formed into a ball when squeezed, does not fall apart when handled, and does not drip water. Adjust the pH to 5~6.5 with a concentration of 1~3mol / L dilute sulfuric acid and then spread it in the seedling tray with a thickness of 1.4~1.6cm. S3. When the germinated seeds weigh 400-600g per tray of seedling substrate, the corresponding sowing amount is 110-130g. Sow the seeds evenly on the surface of the seedling substrate and cover them with soil. S4. Darken the seedling trays after sowing; S5. After emergence, manage water and temperature until the seedlings reach the transplanting standard; among them, before the seedlings reach the 1-leaf-1-heart stage, control the ambient temperature to 20-25℃ during the day and ≥15℃ at night, and adjust ventilation when the temperature is too high; after the seedlings grow to the 2-leaf-1-heart stage, harden them off to keep the day-night temperature difference within 10℃; during the seedling raising process, spray with hymexazol and sodium dichloroisocyanurate every 7 days; when the seedlings grow to the 3-leaf-1-heart stage or the plant height is ≥15cm, transplant them.

7. The seedling raising method according to claim 6, characterized in that, Step S1, the seed soaking process, includes salt water selection, disinfection, and soaking in clean water. The mass concentration of the brine is 8-12%, and the brine selection time is 5-10 minutes. The temperature for soaking the seeds in clean water is 30~35℃, and the time is 24~48h. The water is changed every 12 hours during the soaking process.

8. The seedling raising method according to claim 7, characterized in that, The disinfection treatment in step S1 is carried out using a bactericide solution; the bactericide solution is a solution obtained by diluting imazalil emulsifiable concentrate with an active ingredient content of 20-30% by volume 2000-3000 times. The disinfection process takes 12 to 24 hours and is carried out at a temperature of 15 to 20°C.

9. The seedling raising method according to claim 7 or 8, characterized in that, The germination treatment described in step S1 is carried out at 30~35℃ until the seeds sprout and show white tips, with a sprout length ≤0.5cm; The temperature for the darkening process in step S4 is 25~40℃, and the darkening time is 1~2 days.

10. The seedling raising method according to claim 9, characterized in that, In step S5, the substrate moisture content is adjusted by spray irrigation in the early stage after seedling emergence, so that the substrate moisture content is maintained at 60~70%; the spray irrigation is carried out once in the morning and once in the evening every day, and the temperature of the irrigation water is 15~25℃.

Images