Rice seedling raising optimization substrate and preparation method thereof

Abstract

The application provides a rice seedling raising optimization substrate, which is prepared from fermented rice husks, fillers, binders and the like; after appropriate fermentation treatment of the rice husks, the mechanical properties and seedling properties of the substrate are significantly improved.

Description

Field of Invention:

[0001] This application belongs to the field of rice planting and seedling raising technology. Specifically, this application provides an optimized rice seedling raising substrate and its preparation method. Background technology:

[0002] Rice is one of the main food crops in most Asian countries, including my country. Currently, the main method of rice cultivation in my country is still transplanting after seedling raising.

[0003] Manual transplanting has shortcomings in terms of uniformity, and more importantly, it requires a large amount of valuable labor. Therefore, mechanical transplanting is an inevitable trend in rice transplanting. Optimizing transplanting technology requires, on the one hand, optimizing the substrate composition to improve seedling growth; on the other hand, it also requires improving the mechanical properties of the substrate to meet operational requirements. Summary of the Invention

[0004] On the one hand, this application provides an optimized substrate for rice seedling raising, which includes rice husks, fillers, and binders.

[0005] Furthermore, the filler is kaolin, and the binder is corn starch.

[0006] Furthermore, the rice husk is a fermented rice husk.

[0007] Furthermore, the fermentation process is as follows:

[0008] Crush the rice husks and adjust the moisture content to 35-40 w / w%.

[0009] The inoculation solution was prepared using 3-10 w / v brown sugar water, and the inoculation solution contained 1 × 10⁻⁶ Bacillus subtilis. 6 CFU / mL, Bayer conjugated yeast (Zygosaccharomycesbailii) 1×10 5 CFU / mL, 1×10⁻⁶ Pichia Fermentans fermentation 5 CFU / mL and 0.1-0.3 w / v% calcium lactate;

[0010] Add rice husks to a fermentation container, add inoculum at a total dosage of 10-20 mL / kg of wet rice husks, and ferment at an ambient temperature of 15-30℃ for 7-15 days. During the fermentation period, manually turn the pile 1-3 times a day. After fermentation, sterilize by boiling in water and dry in the sun for later use.

[0011] Further, rice husks are added to a fermentation container, and inoculum is added at a total dosage of 15 mL / kg of wet rice husks. Fermentation is carried out at an ambient temperature of 18-25℃ for 10 days. During the fermentation period, the pile is manually turned twice a day. After fermentation, the rice husks are boiled to sterilize and then dried for later use.

[0012] Furthermore, the emulsifier is 0.2 w / v% calcium lactate.

[0013] Furthermore, the optimized rice seedling substrate also includes one or more layers of seedling film.

[0014] Furthermore, the optimized rice seedling substrate also includes one or more components selected from plant growth regulators, nitrogen, phosphorus, and potassium fertilizers, micronutrient fertilizers, insecticides, fungicides, and acidifiers.

[0015] On the other hand, this application provides a method for preparing the above-mentioned optimized substrate for rice seedling raising, the method comprising:

[0016] Mix crushed rice husks, kaolin, and corn starch evenly in a weight ratio of 12-16:1-3:1-2; add one or more components selected from plant growth regulators, nitrogen, phosphorus, and potassium fertilizers, micronutrient fertilizers, insecticides, fungicides, and acidifiers; and add to seedling trays.

[0017] Further, the crushed rice husks, kaolin, and corn starch are mixed evenly in a weight ratio of 15:2:1.

[0018] On the other hand, this application provides the application of the above-mentioned optimized rice seedling substrate in rice seedling raising.

[0019] In this application embodiment, a 9-inch seedling tray (the standard internal size of commercially available products is 57cm×28cm×2.7cm) was used as an example for various experiments and calculations. Seedling trays of other sizes and shapes are also applicable after appropriate dosage calculations and adjustments.

[0020] The seedling film is made of plastic, linen or non-woven fabric.

[0021] In this embodiment, a commercial seedling strengthening agent is used, which contains fertilizer, growth regulator, acidifier, fungicide and other ingredients. Those skilled in the art can also use commercially available single ingredients to mix and add according to soil conditions and other requirements. Attached Figure Description

[0022] Figure 1 The root-to-crown dry weight ratios for groups A1-A5 are shown below.

[0023] Figure 2 The tensile strength at break for groups A1-A5;

[0024] Figure 3 The root-to-shoot dry weight ratio for each group in which emulsifier was added to the inoculum solution;

[0025] Figure 4 The tensile strength at break of each group after adding emulsifier to the inoculum solution is shown. Detailed Implementation

[0026] Example 1: Basic preparation method of seedling substrate

[0027] Main raw materials and equipment:

[0028] The rice husk raw material was provided by a grain processing enterprise in Jiangxi. After being crushed, it was boiled in water for sterilization (2 minutes) and then dried for later use.

[0029] The seedling strengthening agent was provided by Harbin Binglv Zhongfang Biotechnology Co., Ltd.

[0030] Carbendazim sterilization machine provided to Jinan Yimai Biotechnology Co., Ltd.

[0031] Kaolin and corn starch raw materials were provided by Dongguan Chuangmeijia Chemical Co., Ltd.

[0032] The 9-inch seedling tray (internal dimensions 57cm×28cm×2.7cm, external dimensions 60cm×30cm×3.3cm) is a product sold on Taobao. The substrate in the tray has 14×31 holes.

[0033] Preparation method:

[0034] Mix the crushed rice husks, kaolin, and corn starch evenly in a weight ratio of 15:2:1; add a seedling strengthening agent at a ratio of 0.8 w / w; and add a carbendazim fungicide at a ratio of 0.1 w / w.

[0035] Add the seedlings to the seedling tray and press them flat.

[0036] Seedling raising method:

[0037] The experimental variety was late-season rice Yongyou 1538, and the seeding rate was controlled at 2 seeds per hill using a precision seeder. The same standard was used for seedling emergence, tray placement, and seedling management at all stages.

[0038] Evaluation indicators:

[0039] The following indicators were examined during the 3-leaf-1-heart stage:

[0040] Take 20 seedlings and measure their leaf area, maximum root length, number of roots, and root-to-crown dry weight ratio.

[0041] Substrate breaking tensile strength: Five 25cm square substrate blocks (repeated) are placed horizontally and fixed at one end. The other end is clamped with a clamp and pulled with a handheld digital tensile tester until the substrate block breaks. The tensile strength at break is used as an indicator of the substrate's mechanical properties. This indicator is affected by the substrate's own cohesive force and the root system's binding force.

[0042] Example 2: Improvement of Seedling Substrate – Rice Husk Fermentation Treatment

[0043] Main raw materials and equipment:

[0044] EM bacteria: Jinan Xinshunshida Biotechnology Co., Ltd.;

[0045] Bacillus subtilis (nominal source ATCC 6051), Zygosaccharomycesbailii (nominal source CGMCC No. 2.311), and Pichia Fermentans (nominal source CGMCC No. 2.404) were purchased from Kaiborui Biotechnology Co., Ltd.

[0046] Experimental procedure:

[0047] After crushing the rice husks, spray them with water to adjust the moisture content to 35-40 w / w%. Use 5 w / v brown sugar water to prepare a suitable concentration of bacterial solution as the inoculum. Place the rice husks layer by layer into a fermentation container (homemade 1m... 3 In a fermentation tank (of a certain volume), at a total dosage of 15 mL / kg wet weight of rice husks, an appropriate amount of inoculum was sprayed on each layer, and fermentation was carried out at an ambient temperature of 18-25℃ for 10 days. During this period, the pile was manually turned twice a day; after fermentation, it was boiled in water for 2 minutes for sterilization and then dried for later use. The bacterial composition of the inoculum is shown in Table 1.

[0048] Table 1 shows the different bacterial strain ratios verified.

[0049]

[0050] The substrate preparation process and formula, as well as the seedling raising process, are the same as in Example 1.

[0051] In terms of germination rate, all groups maintained a level of 73-76%, with no significant difference.

[0052] In terms of leaf area, all of them are at a relatively suitable level of around 2.9-3.2.

[0053] The maximum root length and number of roots are shown in Table 2. The root systems of compound microbial agents A3 and A4 are generally better than those of other groups.

[0054] Table 2 Maximum root length and number of roots for groups A1-A5

[0055] Group Average maximum root length (cm) Average number of roots A1 8.45 9.5 A2 8.77 11.8 A3 9.22 12.4 A4 9.31 11.8 A5 8.41 9.1

[0056] From the perspective of root and crown dry weight ratio ( Figure 1 The compound microbial agents A3 and A4 reached a level of around 0.6, which is better than the 0.55-0.57 of other groups.

[0057] Regarding matrix fracture tensile strength ( Figure 2 The mechanical properties of the substrate without rice husk treatment are significantly insufficient, causing inconvenience for later operations such as rolling and transplanting (e.g., easy breakage when extracting the substrate). Fermentation treatment of A1 enhances this property; however, A3 and A4, which are theoretically better (better root development), are significantly deficient in this aspect and are not superior to the unfermented state. It is speculated that this may be due to some influence on the physical properties of the substrate during yeast fermentation. According to previous experiments, adding more starch binder would significantly increase costs, and the changes in substrate properties would also affect seedling growth. The applicant is attempting to improve the fermentation process to address this issue.

[0058] Example 3: Improvement of Seedling Substrate – Addition of Emulsifier

[0059] Main raw materials and equipment:

[0060] Calcium lactate, sodium tripolyphosphate, potassium stearate, Tween 20, and propylene glycol were all food grade and purchased from Hubei Haijia Biotechnology Co., Ltd. and Shandong Xinxiong Biotechnology Co., Ltd.

[0061] Experimental procedure:

[0062] The emulsifiers shown in Table 2 were mixed into the preferred A3 and A4 inoculum formulations of Example 2.

[0063] Table 2. Inoculation solution groups with added emulsifiers

[0064] Group Emulsifier in the inoculation solution A3-1 0.2 w / v% calcium lactate A3-2 0.2 w / v% Sodium tripolyphosphate A3-3 0.2 w / v% potassium stearate A3-4 0.1w / v% Tween 20 A3-5 0.2 w / v % propylene glycol A4-1 0.2 w / v% calcium lactate A4-2 0.2 w / v% Sodium tripolyphosphate A4-3 0.2 w / v% potassium stearate A4-4 0.1w / v% Tween 20 A5-5 0.2 w / v % propylene glycol

[0065] The substrate preparation process and formula, the seedling raising process are the same as in Example 1, and the fermentation process is the same as in Example 2.

[0066] In terms of germination rate, all groups maintained a level of 73-78%.

[0067] In terms of leaf area, all of them are at a relatively suitable level of around 2.9-3.3.

[0068] The maximum root length and number of roots were similar to those of groups A3 and A4, around 9.3 and 11-12, respectively. The Tween combination and propylene glycol group had lower values, around 8.2 and 9.5.

[0069] Regarding the root-to-crown dry weight ratio ( Figure 3 The concentration of A3-1 reached approximately 0.65, significantly higher than the approximately 0.59 without the addition of emulsifier, indicating better seedling vigor. A4-1's concentration of 0.63 was also better than the previous approximately 0.61. The addition of Tween 20 and propylene glycol during fermentation had a significant adverse effect on root growth in the substrate.

[0070] Regarding matrix fracture tensile strength ( Figure 4Although it is not yet clear whether the improvement was due to changes in the substrate or the emulsifier itself, the addition of 0.2 w / v% calcium lactate to the A3-1 inoculum of Bacillus subtilis and two yeasts significantly improved the mechanical properties of the substrate, which was significantly better than other groups, including those with EM inoculum. Considering the increased weight of the substrate blocks after planting and the relatively vigorous movements that are unavoidable during operation, this level of tensile strength can significantly simplify the handling of the substrate blocks and reduce operational interruptions caused by breakage.

Claims

1. An optimized substrate for rice seedling raising, wherein the optimized substrate for rice seedling raising comprises fermented rice husks, kaolin, and corn starch; The method for preparing the fermented rice husk is as follows: (1) Crush the rice husks and adjust the moisture content to 35-40 w / w%. (2) Prepare the inoculation solution using 3-10 w / v brown sugar water, wherein the inoculation solution contains: Bacillus subtilis ( Bacillus subtilis 1×10 6 CFU / mL, Bayer conjugated yeast ( Zygosaccharomyces bailii 1×10 5 CFU / mL, fermented Pichia pastoris ( Pichia Fermentans 1×10 5 CFU / mL and 0.2 w / v% calcium lactate; the Bacillus subtilis strain is ATCC 6051 from the U.S. Type Culture Collection Center; the Bayer conjugating yeast strain is CGMCC No. 2.311 from the China General Microbiological Culture Collection Center; the fermenting Pichia pastoris strain is CGMCC No. 2.404 from the China General Microbiological Culture Collection Center. (3) Add rice husks to the fermentation container, add inoculum at a total amount of 10-20 mL / kg wet weight of rice husks, and ferment at an ambient temperature of 15-30℃ for 7-15 days; During fermentation, the compost pile should be turned manually 1-3 times a day; After fermentation, sterilize by boiling in water, then dry in the sun for later use; The method for preparing the optimized substrate for rice seedling raising includes: mixing fermented rice husks, kaolin, and corn starch evenly in a weight ratio of 12-16:1-3:1-2; adding one or more components selected from plant growth regulators, nitrogen, phosphorus, and potassium fertilizers, micronutrient fertilizers, insecticides, fungicides, and acidifiers; and adding the mixture to seedling trays.

2. According to the optimized substrate for rice seedling raising as described in claim 1, step (3) in the method for preparing fermented rice husks is to add rice husks to a fermentation container, add inoculum at a total amount of 15 mL / kg wet weight of rice husks, and ferment at an ambient temperature of 18-25℃ for 10 days; manually turn the pile twice a day during the fermentation period; sterilize by boiling after fermentation, and dry for later use.

3. The optimized rice seedling substrate according to claim 1, wherein the optimized rice seedling substrate further comprises one or more layers of seedling film.

4. The optimized rice seedling substrate according to claim 3, wherein the seedling film is made of plastic, burlap, or non-woven fabric.

5. The application of the optimized rice seedling substrate according to claim 1 in rice seedling raising.

Images