A light substrate bagging seedling method of a sun-loving arbor

Abstract

The application discloses a light substrate bag seedling method of sun-loving arbor trees and belongs to the technical field of sun-loving arbor tree seedling. In the process of seedling of the sun-loving arbor trees, the seeds are sowed in the substrate bags, and then the substrate bags are placed by using a specific method to improve the light energy utilization rate; meanwhile, a promoter for promoting photosynthesis of seedlings is prepared, and the seedlings are sprayed according to a specific method at different periods, so that the promoter and the specific placing method improve the photosynthesis efficiency of the seedlings and coordinate the growth consistency among the seedlings, and then the high-quality sun-loving arbor tree seedlings with good growth and uniformity are cultivated, and the light substrate bag seedling method has a good application prospect in the field of sun-loving arbor tree seedling.

Description

Technical Field

[0001] This invention relates to the field of tree seedling technology, and in particular to a method for cultivating seedlings of sun-loving trees using lightweight substrate bags. Background Technology

[0002] Seedling cultivation plays a decisive role in plant growth and development. Traditional soil-based seedling cultivation methods were widely used in the past, but with advancements in science and technology and changes in agricultural production methods, traditional seedling techniques can no longer meet the needs of plant growth. To address this issue, lightweight substrate mesh bag container seedling cultivation has been proposed. As an emerging seedling cultivation technology, its unique design and material properties have a positive impact on plant growth and development, showing promising application prospects.

[0003] Lightweight substrate bags are typically used for seedling cultivation by placing the seedlings individually for easy watering and to maintain a stable growing environment. However, for some sun-loving trees, such as *Cinnamomum camphora*, *Phoebe zhennan*, *Machilus yunnanensis*, *Ilex chinensis*, *Nymphaea nigra*, and *Symplocos edulis*, rapid growth in lightweight substrate bags can lead to internal competition for light during the seedling stage. This can result in some seedlings growing weaker due to insufficient light, leading to uneven growth and affecting seedling quality. Increasing the spacing between seedling bags can increase light exposure and reduce internal competition for light. However, if the spacing between the seedling bags is too large, especially when the seedlings have large root canals, watering can easily cause the seedlings to tilt or fall over. Furthermore, the substrate dries out quickly with spacing, and the large canopy can prevent water from penetrating the bags, resulting in uneven moisture levels and hindering growth.

[0004] Therefore, there is a need to find a lightweight substrate bag seedling cultivation method for sun-loving trees to solve the problem that the seedlings grow unevenly and the quality is reduced due to internal light competition under conventional lightweight substrate bag seedling cultivation methods. Summary of the Invention

[0005] Therefore, the purpose of this invention is to provide a method for cultivating seedlings of sun-loving trees using lightweight substrate bags, which solves the problem that the uneven growth of seedlings and reduced seedling quality caused by internal light competition in conventional lightweight substrate bag seedling cultivation methods.

[0006] The present invention solves the above-mentioned technical problems through the following technical means:

[0007] A method for cultivating seedlings of sun-loving trees in lightweight substrate bags, the method comprising the following steps:

[0008] (1) Sow the seeds of sun-loving trees in the substrate bag, place them side by side with two trees in a row, and place the next row with a gap of one tree in the middle. Place the outermost ring of trees in a ring to form an enclosing structure. After placing the trees, half-bury the substrate bag with the substrate in the outermost ring.

[0009] (2) When the seedlings grow to the 2-4 leaf stage, spray all the seedlings with a growth promoter. Then, after 30-50 days, spray the seedlings on the shaded side and the weak seedlings. Then, manage them according to the usual methods.

[0010] Furthermore, the sun-loving tree is any one of the following: camphor tree, nanmu, nanmu, holly, blueberry tree, and Michelia champaca.

[0011] Furthermore, in step (1), the matrix is ​​obtained by mixing peat, perlite, and yellow clay in a mass ratio of 4:2:3.

[0012] Furthermore, the accelerator in step (2) includes the following raw materials:

[0013] Citric acid, formamide, dopamine, nano silica, EDC, NHS, 4-carboxybenzaldehyde, p-aminoazobenzene, sodium carboxymethyl cellulose, L-menthol.

[0014] Furthermore, the method for preparing the accelerator is as follows:

[0015] A: Add citric acid and formamide to water and stir to dissolve. Then heat to 160-180℃ and react for 3-5 hours. After the reaction is complete, cool naturally to room temperature. Centrifuge at 1000 r / min for 10 min to remove the precipitate. Concentrate by rotary evaporation at 60℃ to obtain carbon quantum dots.

[0016] B: Add nano-silica to a 60% ethanol solution and sonicate for 30 min to obtain a nano-silica dispersion; add dopamine to a Tris-HCl buffer solution with pH 8.5 and stir to dissolve to obtain a dopamine solution, then add the nano-silica dispersion, stir at room temperature for 6-8 h, filter to remove the filtrate after the reaction is complete, and dry to obtain pretreated nano-silica.

[0017] C: Add 4-carboxybenzaldehyde to dimethyl sulfoxide and stir to dissolve. Then add EDC and NHS. Stir and react at room temperature for 30-60 min. Then add pretreated nano-silica. Adjust the pH to 7.5-8.5 and stir and react at room temperature for 4-8 h. After the reaction is complete, filter to remove the filtrate. Wash with water 2-3 times and dry to obtain modified nano-silica.

[0018] D: Add modified nano-silica to water and stir to disperse. Adjust the pH to 4-5 and then add carbon quantum dots. Sonicate for 20-30 minutes and let stand at room temperature overnight. Then adjust the pH to 8 and add p-aminoazobenzene. Heat to 40-60℃ and react for 4-8 hours. After the reaction is complete, centrifuge to collect the precipitate and dry it to obtain nano-silica loaded with carbon quantum dots.

[0019] E: Dissolve sodium carboxymethyl cellulose in water by stirring to prepare a 0.5 wt% sodium carboxymethyl cellulose solution. Then add L-menthol and stir continuously at 800-1000 r / min for 5-10 min. Then add nano-silica loaded with carbon quantum dots and stir thoroughly to obtain the accelerator.

[0020] Furthermore, in step A, the mass ratio of citric acid to formamide is (1-2):(2-6).

[0021] Furthermore, in step B, the amount of dopamine added to the dopamine solution is 3-6 g / L.

[0022] Furthermore, in step B, the ratio of nano-silica to dopamine is (0.5-1):(0.03-0.06).

[0023] Furthermore, in step C, the mass ratio of 4-carboxybenzaldehyde, EDC, NHS, and pretreated nano-silica is (0.1-0.2):(0.5-1.1):(0.3-0.7):(0.5-1).

[0024] Furthermore, in step D, the mass ratio of modified nano-silica, carbon quantum dots, and p-aminoazobenzene is (0.5-1):(0.2-0.6):(0.05-0.1).

[0025] Furthermore, in step E, the mass ratio of carboxymethyl cellulose solution, L-menthol, and carbon quantum dot-loaded nano-silica is (2-4):(0.01-0.02):(0.5-1).

[0026] This invention uses citric acid and formamide to prepare carbon quantum dot materials through co-heating. Carbon quantum dots can increase chlorophyll content, accelerate electron transfer, and enhance Rubisco enzyme activity, thereby improving plant photosynthesis and accelerating carbohydrate accumulation. Combined with the substrate-based seedling placement method of this invention, it can improve plant light energy utilization, promote photosynthesis, and better regulate the uniformity of seedling photosynthesis, thus cultivating high-quality seedlings with good growth and uniformity. However, the prepared carbon quantum dot material has good water solubility, and direct spraying onto seedlings can easily lead to loss and waste, shortening the action time and reducing the effect. Therefore, this invention combines the prepared carbon quantum dots with nano-silica, p-aminoazobenzene, L-menthol, and other raw materials to prepare a photosynthesis promoter with good adhesion and slow-release properties, ensuring the full effect of the carbon quantum dots, promoting seedling growth, improving seedling uniformity, and thus cultivating high-quality seedlings.

[0027] Specifically, this invention sequentially treats nano-silica with dopamine and 4-carboxybenzaldehyde. Dopamine binds to the nano-silica, enhancing the interaction between the nano-silica and plant leaves by adjusting the surface chemical properties of the nano-silica, thereby improving the adhesion of the nano-silica to the leaves. Further, 4-carboxybenzaldehyde is then bound to the dopamine-treated nano-silica to obtain modified nano-silica. Carbon quantum dots are loaded onto the modified nano-silica, and then treated with p-aminoazobenzene. The surface groups of the nano-silica modified with p-aminoazobenzene and 4-carboxybenzaldehyde condense and bind to the nano-silica loaded with carbon quantum dots, thus encapsulating the loaded carbon quantum dots. Due to the photoisomerization of p-aminoazobenzene, after being sprayed onto the surface of plant leaves, it undergoes isomerization under light, releasing the internally embedded carbon quantum dots, achieving slow release of the carbon quantum dots. The slowly released carbon quantum dots continuously enhance the photosynthesis of seedlings. By combining the method of first spraying the entire seedling, and then spraying the weak seedlings and the shaded side of the seedlings, we can cultivate superior seedlings with good growth and uniform growth.

[0028] This invention also adds L-menthol and modified nano-silica loaded with carbon quantum dots to prepare a promoter. L-menthol and modified nano-silica are attached to the nano-silica through hydrogen bonding and other means. After being applied to the leaf surface, it changes the surface tension of the microenvironment around the stomata of the leaf, ensuring that the carbon quantum dots slowly released from the nano-silica can smoothly enter the leaf interior, ensuring the efficient photosynthesis of seedlings. Furthermore, through the synergistic effect of the components in the promoter, the carbon quantum dot material is ensured to have good adhesion and slow-release performance on the plant surface, continuously and effectively promoting the photosynthesis of seedlings, thereby cultivating high-quality tree seedlings.

[0029] Beneficial effects:

[0030] This invention arranges sun-loving trees in a light substrate bag seedling method according to a specific method, and applies a photosynthesis promoter with carbon quantum dots as the key component to ensure that the tree seedlings make full use of light energy and improve photosynthetic efficiency, so as to cultivate high-quality tree seedlings with good growth and uniformity. Attached Figure Description

[0031] Figure 1 : This is a picture showing the arrangement of holly seedlings in lightweight substrate bags according to the present invention. Detailed Implementation

[0032] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings:

[0033] Example 1: Preparation of Accelerator

[0034] A: Citric acid and formamide were mixed in a mass ratio of 1.5:4 and then added to 10 times the mass of water and stirred to dissolve. The mixture was then heated to 170℃ and reacted for 4 hours. After the reaction was completed, the mixture was naturally cooled to room temperature. After centrifugation at 1000 r / min for 10 minutes, the precipitate was removed. The mixture was then concentrated by rotary evaporation at 60℃ to obtain carbon quantum dots.

[0035] B: 0.7 kg of nano-silica was added to 1.4 kg of 60% ethanol solution and sonicated at 20 kHz for 30 min to obtain a nano-silica dispersion; 0.045 kg of dopamine was added to 10 L of Tris-HCl buffer solution with pH 8.5 to prepare a dopamine solution, and then the nano-silica dispersion was added. The mixture was stirred at room temperature for 7 h. After the reaction was completed, the filtrate was removed by filtration and dried at 45 °C to obtain pretreated nano-silica.

[0036] C: Add 0.15 kg of 4-carboxybenzaldehyde to 7.5 kg of dimethyl sulfoxide and stir to dissolve. Then add 0.7 kg of EDC and 0.5 kg of NHS. Stir and react at room temperature for 40 min. Then add 0.7 kg of pretreated nano-silica. Adjust the pH to 8 and stir and react at room temperature for 6 h. After the reaction is complete, filter to remove the filtrate, wash with water 3 times and dry at 45 °C to obtain modified nano-silica.

[0037] D: Add 0.7 kg of modified nano-silica to 1.4 kg of water and stir to disperse. After adjusting the pH to 4.5, add 0.4 kg of carbon quantum dots. Sonicate at 20 kHz for 25 min and let stand at room temperature overnight. Then adjust the pH to 8 and add 0.07 kg of p-aminoazobenzene. Heat to 50 ℃ and react for 6 h. After the reaction is complete, centrifuge at 900 r / min for 7 min. Then take the precipitate and dry it at 45 ℃ to obtain nano-silica loaded with carbon quantum dots.

[0038] E: Dissolve sodium carboxymethyl cellulose in water by stirring to prepare 3 kg of 0.5 wt% sodium carboxymethyl cellulose solution. Then add 0.015 kg of L-menthol and stir continuously at 900 r / min for 8 min. Then add 0.7 kg of carbon quantum dot-loaded nano-silica and stir thoroughly to obtain the accelerator.

[0039] Example 2: Preparation of Accelerator II

[0040] A: Citric acid and formamide were mixed in a mass ratio of 1:2 and then added to 10 times the mass of water and stirred to dissolve. The mixture was then heated to 160℃ and reacted for 5 hours. After the reaction was completed, the mixture was naturally cooled to room temperature. After centrifugation at 1000 r / min for 10 minutes, the precipitate was removed. The mixture was then concentrated by rotary evaporation at 60℃ to obtain carbon quantum dots.

[0041] B: 0.5 kg of nano-silica was added to 1 kg of 60% ethanol solution and sonicated at 20 kHz for 30 min to obtain a nano-silica dispersion; 0.03 kg of dopamine was added to 10 L of Tris-HCl buffer solution with pH 8.5 to prepare a dopamine solution, and then the nano-silica dispersion was added. The mixture was stirred at room temperature for 6 h. After the reaction was completed, the filtrate was removed by filtration and dried at 45 °C to obtain pretreated nano-silica.

[0042] C: Add 0.1 kg of 4-carboxybenzaldehyde to 5 kg of dimethyl sulfoxide and stir to dissolve. Then add 0.5 kg of EDC and 0.3 kg of NHS. Stir and react at room temperature for 30 min. Then add 0.5 kg of pretreated nano-silica. Adjust the pH to 7.5 and stir and react at room temperature for 4 h. After the reaction is complete, filter to remove the filtrate, wash twice with water and dry at 45 °C to obtain modified nano-silica.

[0043] D: Add 0.5 kg of modified nano-silica to 1 kg of water and stir to disperse. After adjusting the pH to 4, add 0.2 kg of carbon quantum dots. Sonicate at 20 kHz for 20 min and let stand at room temperature overnight. Then adjust the pH to 8 and add 0.05 kg of p-aminoazobenzene. Heat to 40 ℃ and react for 4 h. After the reaction is complete, centrifuge at 800 r / min for 10 min. Then take the precipitate and dry it at 45 ℃ to obtain nano-silica loaded with carbon quantum dots.

[0044] E: Dissolve sodium carboxymethyl cellulose in water by stirring to prepare 2 kg of 0.5 wt% sodium carboxymethyl cellulose solution. Then add 0.01 kg of L-menthol and stir continuously at 800 r / min for 10 min. Then add 0.5 kg of carbon quantum dot-loaded nano-silica and stir thoroughly to obtain the accelerator.

[0045] Example 3: Preparation of Accelerator

[0046] A: Citric acid and formamide were mixed in a mass ratio of 2:6 and then added to 10 times the mass of water and stirred to dissolve. The mixture was then heated to 180℃ and reacted for 3 hours. After the reaction was completed, the mixture was naturally cooled to room temperature. After centrifugation at 1000 r / min for 10 minutes, the precipitate was removed. The mixture was then concentrated by rotary evaporation at 60℃ to obtain carbon quantum dots.

[0047] B: 1 kg of nano-silica was added to 2 kg of 60% ethanol solution and sonicated at 20 kHz for 30 min to obtain a nano-silica dispersion; 0.06 kg of dopamine was added to 10 L of Tris-HCl buffer solution with pH 8.5 to prepare a dopamine solution, and then the nano-silica dispersion was added. The mixture was stirred at room temperature for 8 h. After the reaction was completed, the filtrate was removed by filtration and dried at 45 °C to obtain pretreated nano-silica.

[0048] C: 0.2 kg of 4-carboxybenzaldehyde was added to 10 kg of dimethyl sulfoxide and stirred to dissolve. Then, 1.1 kg of EDC and 0.7 kg of NHS were added. The mixture was stirred at room temperature for 60 min and then 1 kg of pretreated nano-silica was added. The pH was adjusted to 8.5 and the mixture was stirred at room temperature for 8 h. After the reaction was completed, the filtrate was filtered off and washed with water 3 times. The mixture was then dried at 45 °C to obtain modified nano-silica.

[0049] D: Add 1 kg of modified nano-silica to 2 kg of water and stir to disperse. After adjusting the pH to 5, add 0.6 kg of carbon quantum dots. Sonicate at 20 kHz for 30 min and let stand at room temperature overnight. Then adjust the pH to 8 and add 0.1 kg of p-aminoazobenzene. Heat to 60 ℃ and react for 8 h. After the reaction is complete, centrifuge at 1000 r / min for 10 min. Then take the precipitate and dry it at 45 ℃ to obtain nano-silica loaded with carbon quantum dots.

[0050] E: Dissolve sodium carboxymethyl cellulose in water by stirring to prepare 4 kg of 0.5 wt% sodium carboxymethyl cellulose solution. Then add 0.02 kg of L-menthol and stir continuously at 1000 r / min for 5 min. Then add 1 kg of carbon quantum dot-loaded nano-silica and stir thoroughly to obtain the accelerator.

[0051] Comparative Example 1: Preparation of Accelerator

[0052] Compared with Example 1, the only difference is that the original step A was omitted in the preparation of the accelerator in Comparative Example 1, i.e., dopamine was not used to pretreat the nano-silica, as shown below:

[0053] A: Same as Example 1;

[0054] B: Add 0.15 kg of 4-carboxybenzaldehyde to 7.5 kg of dimethyl sulfoxide and stir to dissolve. Then add 0.7 kg of EDC and 0.5 kg of NHS. Stir and react at room temperature for 40 min. Then add 0.7 kg of nano silica. Adjust the pH to 8 and stir and react at room temperature for 6 h. After the reaction is complete, filter to remove the filtrate. Wash with water 3 times and dry at 45 °C to obtain modified nano silica.

[0055] C: Same as step D in Example 1;

[0056] E: Same as step E in Example 1.

[0057] Comparative Example 2: Preparation of Accelerator

[0058] Compared with Example 1, the only difference is that step C is missing in the preparation of the accelerator in Comparative Example 2, which involves treating the pretreated nano-silica with 4-carboxybenzaldehyde, as shown below:

[0059] A-B: Same as in Example 1;

[0060] C: Add 0.7 kg of pretreated nano-silica to 1.4 kg of water and stir to disperse. After adjusting the pH to 4.5, add 0.4 kg of carbon quantum dots. Sonicate at 20 kHz for 25 min and let stand at room temperature overnight. Then adjust the pH to 8 and add 0.07 kg of p-aminoazobenzene. Heat to 50 °C and react for 6 h. After the reaction is complete, centrifuge at 900 r / min for 7 min. Then take the precipitate and dry it at 45 °C to obtain nano-silica loaded with carbon quantum dots.

[0061] D: Same as step E in Example 1.

[0062] Comparative Example 3: Preparation of Accelerator

[0063] Compared with Example 1, the only difference is that p-aminoazobenzene was not added in step D during the preparation of the accelerator in Comparative Example 3, as shown below:

[0064] A-C: Same as in Example 1;

[0065] D: Add 0.7 kg of modified nano silica to 1.4 kg of water and stir to disperse. After adjusting the pH to 4.5, add 0.4 kg of carbon quantum dots. Sonicate at 20 kHz for 25 min and let stand at room temperature overnight. Centrifuge at 900 r / min for 7 min. Then take the precipitate and dry it at 45 ℃ to obtain nano silica loaded with carbon quantum dots.

[0066] E: Same as in Example 1.

[0067] Comparative Example 4: Preparation of Accelerator

[0068] Compared with Example 1, the only difference is that L-menthol was not added in step E of the preparation of the accelerator in Comparative Example 4, as shown below:

[0069] A-D: Same as in Example 1;

[0070] E: Dissolve sodium carboxymethyl cellulose in water by stirring to prepare 3 kg of 0.5 wt% sodium carboxymethyl cellulose solution. Then add 0.7 kg of carbon quantum dot-loaded nano-silica and stir thoroughly to obtain the accelerator.

[0071] Comparative Example 5: Preparation of Accelerator

[0072] Compared with Example 1, the only difference is that in Comparative Example 5, the pH was adjusted to 6.5 in step C during the preparation of the accelerator; all other steps were the same as in Example 1.

[0073] Comparative Example 6: Preparation of Accelerator

[0074] Compared with Example 1, the only difference is that in Comparative Example 6, the pH was adjusted to 9.5 in step C during the preparation of the accelerator; all other steps were the same as in Example 1.

[0075] Comparative Example 7: Preparation of Accelerator

[0076] Compared with Example 1, the only difference is that in Comparative Example 7, the amount of 4-carboxybenzaldehyde added in step C during the preparation of the accelerator is 0.05 kg, and the other steps are the same as in Example 1.

[0077] Comparative Example 8: Preparation of Accelerator

[0078] Compared with Example 1, the only difference is that in Comparative Example 8, the amount of 4-carboxybenzaldehyde added in step C during the preparation of the accelerator is 0.3 kg, and the other steps are the same as in Example 1.

[0079] Comparative Example 9: Preparation of Accelerator

[0080] Compared with Example 1, the only difference is that in Comparative Example 9, the amount of p-aminoazobenzene D added in step D during the preparation of the accelerator is 0.02 kg, and the other steps are the same as in Example 1.

[0081] Comparative Example 10: Preparation of Accelerator

[0082] Compared with Example 1, the only difference is that in Comparative Example 10, the amount of p-aminoazobenzene added in step D during the preparation of the accelerator is 0.13 kg, and all other steps are the same as in Example 1.

[0083] Example 4: Lightweight substrate bag seedling cultivation method for holly

[0084] (1) Mix peat, perlite and yellow soil in a mass ratio of 4:2:3 to obtain a substrate. Put the substrate into a substrate bag. Then sow holly seeds in the seedling bag at a rate of one seed per bag. First, place two seedlings in a row side by side, then place another row with a gap of one seed in the middle. Place the seeds around the outermost edge in a surrounding structure. After placing the seeds, half-bury the substrate bag with the substrate around the outermost edge. Water the seedling bag as usual.

[0085] (2) When the holly seedlings grow to the 3-leaf stage, prepare the growth promoter according to the method of Example 1. Apply 20g of growth promoter to all seedlings. Then, after 40 days, spray the growth promoter on the shaded side of the seedlings and on the weak seedlings at a rate of 10g per seedling. Continue to manage the seedlings according to the conventional method.

[0086] Experiment: Lightweight substrate bag seedling cultivation experiment of holly

[0087] 1. Holly seedlings were raised in lightweight substrate bags at Gele Mountain, Shapingba District, Chongqing. The experiment was divided into 13 groups: experimental group 1, control group 1-11, and blank control group. Each group was sown and placed in 30 pots according to the method in step (1) of Example 4. Then, at the 3-leaf stage, a growth promoter was sprayed. The specific details of each group are as follows:

[0088] Experimental group 1 was sprayed with the accelerator prepared in Example 1 according to step (2) of Example 4;

[0089] Control groups 1-10 were sprayed with the accelerators of comparative examples 1-10 respectively, as in step (2) of Example 4;

[0090] In control group 11, the accelerator prepared in Example 1 was sprayed according to step (2) of Example 4, but the bags were placed side by side.

[0091] The blank control group was not sprayed with the accelerator, but instead was given an equal amount of water, and the bags were placed side by side during spraying.

[0092] Each group selected plump, disease-free holly seeds for sowing and carried out watering and other management operations in the same manner. Thirty days after the second application of the growth promoter, the growth of holly seedlings in each group was statistically analyzed, including: average plant height and weak seedling rate (the proportion of seedlings with a height less than 2 cm below the average plant height). The data obtained from the three replicate experiments are shown in Table 1.

[0093] Table 1

[0094]

[0095]

[0096] Based on the data analysis in Table 1, we can conclude that:

[0097] (1) In experimental group 1, the average height of the seedlings reached 12.6 cm, while the rate of weak seedlings (less than 2 cm below the average height) was only 5.6%. This indicates that the method of cultivating holly seedlings in light substrate bags according to the present invention can effectively improve seedling growth, and the cultivated seedlings have relatively uniform height and good quality. In control group 11, a growth promoter was sprayed, but the bags were placed side by side, resulting in poor light absorption for some seedlings and a significant increase in the rate of weak seedlings. In the blank control group, the bags were placed side by side and no growth promoter was sprayed, resulting in a significant decrease in seedling height and an increase in the rate of weak seedlings.

[0098] (2) In control group 1, dopamine was not used to treat the nano-silica during the preparation of the promoter. The nano-silica loaded with carbon quantum dots had poor adhesion on the leaves, which led to the loss and waste of the effective ingredient carbon quantum dots, reducing the photosynthetic promotion effect and resulting in a significant reduction in plant height. In control group 2, 4-carboxybenzaldehyde was not used to treat the pretreated nano-silica during the preparation of the promoter, which affected the binding of photoresponsive p-aminoazobenzene. In control group 3, p-aminoazobenzene was not added during the preparation of the promoter. In control groups 2 and 3, the encapsulation effect of the effective ingredient carbon quantum dots was affected, which not only caused the loss and waste of carbon quantum dots, but also reduced the sustained effect of the effective ingredient in the promoter, resulting in a worse photosynthetic promotion effect.

[0099] (3) In control group 4, L-menthol was not added during the preparation of the accelerator, which affected the utilization rate of carbon quantum dots by the seedlings, thus resulting in a poorer effect of the photosynthesis accelerator. In control groups 5 and 6, the pH was adjusted to 6.5 and 9.5 respectively in step C during the preparation of the accelerator. In control group 7, the amount of 4-carboxybenzaldehyde added was too small, and in control group 8, the amount of 4-carboxybenzaldehyde added was too large. Due to the changes in the conditions and the amount of 4-carboxybenzaldehyde during the preparation of the accelerator, the subsequent binding of the photoresponsive material azobenzene was affected in control groups 5 to 8, thus affecting the photoresponsive release of the accelerator and reducing the photocatalytic effect of the accelerator. In control group 9, the amount of p-aminoazobenzene added was too small, and in control group 10, the amount of p-aminoazobenzene added was too large. The unsuitable amount of azobenzene added in control groups 9 and 10 affected the release of carbon quantum dots in nano-silica, thus affecting the effect of the accelerator.

[0100] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention. Technical aspects, shapes, and structures not described in detail in this invention are all well-known technologies.

Claims

1. A method for cultivating seedlings of sun-loving trees in lightweight substrate bags, characterized in that, The method is as follows: (1) Sow the seeds of sun-loving trees in the substrate bag and place them side by side with two trees in a row, with a gap of one tree in the middle before placing the next row. Place the seeds in the outermost ring in a surrounding structure. After placing the seeds, half-bury the substrate bag with the substrate in the outermost ring. (2) When the seedlings grow to the 2-4 leaf stage, spray all the seedlings with a growth promoter. Then, after 30-50 days, spray the seedlings on the shaded side and the weak seedlings. Then, manage them according to the conventional method. The accelerator comprises the following raw materials: Citric acid, formamide, dopamine, nano silica, EDC, NHS, 4-carboxybenzaldehyde, p-aminoazobenzene, sodium carboxymethyl cellulose, L-menthol; The method for preparing the accelerator is as follows: A: Add citric acid and formamide to water and stir to dissolve. Then heat to 160-180℃ and react for 3-5 hours. After the reaction is complete, cool naturally to room temperature. Centrifuge at 1000 r / min for 10 min to remove the precipitate. Concentrate by rotary evaporation at 60℃ to obtain carbon quantum dots. B: Add nano-silica to a 60% ethanol solution and sonicate for 30 min to obtain a nano-silica dispersion; add dopamine to a Tris-HCl buffer solution with pH 8.5 and stir to dissolve to obtain a dopamine solution, then add the nano-silica dispersion, stir at room temperature for 6-8 h, filter to remove the filtrate after the reaction is complete, and dry to obtain pretreated nano-silica. C: Add 4-carboxybenzaldehyde to dimethyl sulfoxide and stir to dissolve. Then add EDC and NHS. Stir and react at room temperature for 30-60 min. Then add pretreated nano-silica. Adjust the pH to 7.5-8.5 and stir and react at room temperature for 4-8 h. After the reaction is complete, filter to remove the filtrate. Wash with water 2-3 times and dry to obtain modified nano-silica. D: Add modified nano-silica to water and stir to disperse. Adjust the pH to 4-5 and then add carbon quantum dots. Sonicate for 20-30 minutes and let stand at room temperature overnight. Then adjust the pH to 8 and add p-aminoazobenzene. Heat to 40-60℃ and react for 4-8 hours. After the reaction is complete, centrifuge to collect the precipitate and dry it to obtain nano-silica loaded with carbon quantum dots. E: Dissolve sodium carboxymethyl cellulose in water by stirring to prepare a 0.5 wt% sodium carboxymethyl cellulose solution. Then add L-menthol and stir continuously at 800-1000 r / min for 5-10 min. Then add nano-silica loaded with carbon quantum dots and stir thoroughly to obtain the accelerator.

2. The method for cultivating light-substrate bag seedlings of sun-loving trees according to claim 1, characterized in that, The sun-loving trees mentioned are any one of the following: camphor tree, nanmu, nanmu, holly, blueberry tree, and Michelia champaca.

3. The method for cultivating light-substrate bag seedlings of sun-loving trees according to claim 2, characterized in that, In step A, the mass ratio of citric acid to formamide is (1-2):(2-6).

4. The method for cultivating light-substrate bag seedlings of sun-loving trees according to claim 3, characterized in that, In step B, the amount of dopamine added to the dopamine solution is 3-6 g / L.

5. The method for cultivating light-substrate bag seedlings of sun-loving trees according to claim 4, characterized in that, In step B, the ratio of nano-silica to dopamine is (0.5-1):(0.03-0.06).

6. The method for cultivating light-substrate bag seedlings of sun-loving trees according to claim 5, characterized in that, In step C, the mass ratio of 4-carboxybenzaldehyde, EDC, NHS, and pretreated nano-silica is (0.1-0.2):(0.5-1.1):(0.3-0.7):(0.5-1).

7. The method for cultivating light-substrate bag seedlings of sun-loving trees according to claim 6, characterized in that, In step D, the mass ratio of modified nano-silica, carbon quantum dots, and p-aminoazobenzene is (0.5-1):(0.2-0.6):(0.05-0.1).

8. A method for cultivating light-substrate bag seedlings of sun-loving trees according to claim 7, characterized in that... In step E, the mass ratio of carboxymethyl cellulose solution, L-menthol, and carbon quantum dot-loaded nano-silica is (2-4):(0.01-0.02):(0.5-1).

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