Preparation method and application of liquid spraying film for improving pod shattering resistance of rape

Abstract

The invention discloses a preparation method and application of a liquid spraying film for improving pod shattering resistance of rape, and relates to the technical field of agricultural planting. The liquid spraying film is prepared from sodium carboxymethyl cellulose (CMC) and a cross-linking agent, and the sodium carboxymethyl cellulose (CMC) and the cross-linking agent are added into the liquid spraying film. The liquid spraying film is used, a coating film is formed on the surface of the silique, the silique shattering resistance of the rape silique in different mature periods is improved in a physical bonding mode, the silique cracking and shattering conditions in the mechanical harvesting process of the rape are reduced, the mechanical harvesting adaptability of the rape is improved, meanwhile, the liquid spraying film is derived from straw-based biomass, the production process is green and safe, and the application range is wide. The quality of rapeseeds cannot be influenced.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural planting, and in particular to a preparation method and application of a liquid spraying film for improving the resistance of rapeseed to corner cracking. Background Art

[0002] my country is one of the world's major rapeseed producers, with the largest planting area and yield in the world. However, the mechanized harvesting rate of rapeseed in my country is low, far lower than that of grain crops such as rice and wheat. Mechanized harvesting can reduce the labor intensity during rapeseed harvesting, greatly reduce manpower input, and thus reduce production costs. It is conducive to the large-scale and intensive development of rapeseed production in my country and is the inevitable direction of rapeseed production development. Mechanized harvesting has high requirements for the consistency of rapeseed silique maturity, but the maturity period of siliques of the whole rapeseed plant is not consistent, resulting in different water contents in siliques of different parts, which affects the resistance of rapeseed siliques to pod cracking.

[0003] Rapeseed siliques have the characteristic of cracking, that is, rapeseed siliques at the fully mature stage are easily broken under the action of external forces, causing the seeds to fall off. The easy bursting of siliques after maturity is the main problem in rapeseed harvesting. On the one hand, it can cause 8% to 12% yield loss, and on the other hand, it directly affects the mechanized harvesting of rapeseed. Solving the problem of rapeseed siliques being easy to crack can not only increase rapeseed yield, but also greatly promote the mechanization process of rapeseed production, improve rapeseed production efficiency and reduce production costs, which has positive significance for the development of my country's rapeseed industry.

[0004] At present, most of the production is carried out by spraying chemical ripening agents such as ethephon, glyphosate, etc., to promote the uniform maturity of rapeseed siliques and reduce the losses caused by mechanized harvesting. However, relevant studies have shown that the yield and grain quality of crops such as wheat and rice have decreased to varying degrees after chemical ripening treatment. Therefore, the present invention provides a liquid spray film for improving the resistance of rapeseed to pod cracking. By applying a liquid spray material to form a coating on the surface of the silique, the resistance of pod cracking of siliques at different maturity stages is improved from a physical level, and the cracking and grain shedding of rapeseed siliques is reduced. Summary of the invention

[0005] The purpose of the present invention is to provide a preparation method and application of a liquid spray film for improving the pod cracking resistance of rapeseed, to form a coating on the surface of the pod, to improve the pod cracking resistance of rapeseed pods at different maturity stages by physical bonding, to reduce the cracking and grain falling of the pods during mechanical harvesting of rapeseed, and to improve the adaptability of mechanical harvesting of rapeseed. At the same time, the liquid spray film is derived from straw-based biomass, the production process is green and safe, and will not affect the quality of rapeseed grains.

[0006] To achieve the above object, the present invention provides a method for preparing a liquid spray film for improving the resistance of rapeseed to corner cracking, comprising the following steps:

[0007] Step 1: extracting cellulose, adding 5% to 6% alkaline solution to the bio-straw, stirring and reacting at 80 to 150° C. for 0.5 to 4 hours, washing the filter residue with distilled water, and freeze-drying the filter residue to obtain cellulose;

[0008] Step 2: Prepare CMC, add 4g of cellulose to 50-200mL of sodium hydroxide / ethanol solution, stir the mixture at 70-90°C for 60-120min; add 5-8mL of chloroacetic acid / sodium acetate solution and 0.5-1mL of potassium iodide / sodium acetate solution, and react for 110-130min; then add 25-100mL of sodium hydroxide / ethanol solution, and keep stirring for 60-120min; then, adjust the pH of the reactant to 6.0-7.0 with 5%-10% hydrochloric acid aqueous solution; filter and wash the reactant, put it into a freeze dryer for freeze drying, and obtain CMC;

[0009] Step 3: Prepare a liquid spray film, mix CMC and PVA thoroughly, then add a crosslinking agent, heat in a water bath for 60 to 120 minutes at a heating temperature of 60 to 70° C., and obtain a liquid spray film after the reaction is completed.

[0010] Furthermore, in step 1, the biostraw includes rice, corn, wheat, cotton, rape straw, bamboo powder or wood powder, and the particle size is 25-1000 mesh.

[0011] Furthermore, in step 1, the ratio of the biostraw to the alkaline solution is 1:7-15 (w / w).

[0012] Furthermore, in step 1, the alkaline solution is sodium hydroxide solution, sodium hydroxide / sodium chlorite solution, sodium hydroxide / hydrogen peroxide solution or sodium hydroxide / sodium chlorite solution.

[0013] Furthermore, the sodium hydroxide / ethanol solution in step 2 is prepared by adding 8 to 12 g of NaOH to 100 mL of ethanol solution and stirring to obtain a sodium hydroxide / ethanol solution;

[0014] The preparation method of the chloroacetic acid / sodium acetate solution is as follows: 5-12 g of chloroacetic acid is added to 5 mL of ethanol solution, and then 1-2 g of sodium acetate is added and stirred evenly to obtain the chloroacetic acid / sodium acetate solution;

[0015] The potassium iodide / sodium acetate solution is prepared by adding 1-3 g of potassium iodide and 1-3 g of sodium acetate into 100 ml of distilled water and stirring the mixture to obtain the potassium iodide / sodium acetate solution.

[0016] Furthermore, the mixing process of CMC and PVA in step 3 is as follows: 1-2 g CMC is added to 50 mL deionized water, and after being completely dissolved, 20-50 mL of 2%-5% PVA aqueous solution is added to the CMC solution and mixed evenly.

[0017] Furthermore, in step 3, the crosslinking agent includes 0.5% to 5% of glutaraldehyde, 0.5% to 5% of citric acid and 0.2% to 2.0% of epoxy silane.

[0018] The present invention also provides a liquid spraying film for improving the resistance of rapeseed to corner cracking, which is prepared by the above-mentioned preparation method.

[0019] The present invention also provides application of the liquid spraying film in improving the resistance of rapeseed to corner cracking.

[0020] The present invention also provides a method for improving the resistance of rapeseed to pod cracking, using the above liquid spray film when the rapeseed pods are yellow and ripe, spraying the pods, spraying them again after they are dried, and repeating this three times to form a coating on the pod surface.

[0021] The advantages and positive effects of the preparation method and application of a liquid spray film for improving the crack resistance of rapeseed according to the present invention are:

[0022] 1. The liquid spray film in the present invention forms a coating on the surface of the silique, which improves the resistance of rapeseed siliques at different maturity stages to pod cracking by physical bonding, reduces the pod cracking and grain shedding during mechanical harvesting of rapeseed, and improves the adaptability of mechanical harvesting of rapeseed.

[0023] 2. The raw materials of the liquid spray film in the present invention are derived from straw-based biomass, the production process is green and safe, and will not affect the quality of rapeseed grains.

[0024] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the result of the anti-cracking coefficient of rapeseed siliques in Example 1 of the present invention. DETAILED DESCRIPTION

[0026] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0027] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0028] Unless otherwise defined, the reagents, instruments and equipment used in the present invention are all conventionally commercially available.

[0029] Example 1 Preparation of liquid spray film

[0030] Step 1, extracting cellulose from rape straw: 100 g rape straw and 700 mL 5% sodium hydroxide solution were stirred at 80° C. for 4 h, the residue was washed with distilled water, and the residue was freeze-dried to obtain cellulose.

[0031] Step 2, preparing CMC using the extracted cellulose:

[0032] ①Prepare solution:

[0033] Prepare sodium hydroxide / ethanol solution by adding 8 g of NaOH into 100 mL of ethanol solution and stirring well.

[0034] Prepare chloroacetic acid / sodium acetate solution by adding 5 g chloroacetic acid to 5 mL ethanol solution, then add 2 g sodium acetate and stir well to complete the preparation.

[0035] Prepare potassium iodide / sodium acetate solution by adding 2g potassium iodide and 2g sodium acetate into 100ml distilled water and stirring evenly.

[0036] ② Preparation of CMC:

[0037] 4 g of cellulose was added to 150 mL of sodium hydroxide / ethanol solution, and the mixture was stirred at 70 ° C for 60 min. Then 8 mL of chloroacetic acid / sodium acetate solution and 0.5 mL of potassium iodide / sodium acetate solution were added and reacted for 110 min. Subsequently, 80 mL of sodium hydroxide / ethanol solution was added to the reactant and stirred for 120 min. Finally, the pH of the reactant was adjusted to 6.4 using a 5% hydrochloric acid aqueous solution. After washing and filtering, the mixture was placed in a freeze dryer for freeze drying to obtain the synthesized CMC.

[0038] Step 3, preparing liquid spraying membrane material:

[0039] Add 1g CMC to 50mL deionized water. After CMC is completely dissolved, add 50mL of 4% PVA aqueous solution to the CMC solution and mix thoroughly. Then, add 0.1g of 50% glutaraldehyde solution. Heat and stir at 60℃ for 120min to obtain a liquid spray film.

[0040] Example 2 Preparation of liquid spray film

[0041] Step 1, extracting cellulose from corn stalks: 100 g corn stalks and 700 mL 5% sodium chlorite solution were stirred at 100° C. for 2 h, the residue was washed with distilled water, and the residue was freeze-dried to obtain cellulose.

[0042] Step 2, preparing CMC using the extracted cellulose:

[0043] ①Prepare solution:

[0044] Prepare sodium hydroxide / ethanol solution by adding 10 g of NaOH into 100 mL of ethanol solution and stirring evenly.

[0045] Prepare chloroacetic acid / sodium acetate solution by adding 5 g chloroacetic acid to 5 mL ethanol solution, then add 2 g sodium acetate and stir well to complete the preparation.

[0046] Prepare potassium iodide / sodium acetate solution by adding 2g potassium iodide and 2g sodium acetate into 100ml distilled water and stirring evenly.

[0047] ② Preparation of CMC:

[0048] 4 g of cellulose was added to 150 mL of sodium hydroxide / ethanol solution, and the mixture was stirred at 80 ° C for 90 min. 8 mL of chloroacetic acid / sodium acetate solution and 0.8 mL of potassium iodide / sodium acetate solution were added, and the reaction time was 110 min. Subsequently, 80 mL of sodium hydroxide / ethanol solution was added to the reactant and stirred for 120 min. Finally, the pH of the reactant was adjusted to 6.7 using 5% hydrochloric acid solution. The reactant was filtered and washed, and placed in a freeze dryer for freeze drying to obtain synthetic CMC.

[0049] Step 3, preparing liquid spraying membrane material:

[0050] Add 1g CMC to 50mL deionized water. After CMC is completely dissolved, add 50mL of 4% PVA aqueous solution to the CMC solution and mix thoroughly. Then, add 3% citric acid solution. Heat and stir at 60℃ for 120min to obtain a liquid spray film.

[0051] Example 3 Preparation of liquid spray film

[0052] Step 1, extracting cellulose from wheat straw: 100 g of wheat straw and 700 mL of 6% sodium hydroxide solution were stirred at 100° C. for 2 h, the residue was washed with distilled water, and the residue was freeze-dried to obtain cellulose.

[0053] Step 2, preparing CMC using the extracted cellulose:

[0054] ①Prepare solution:

[0055] Prepare sodium hydroxide / ethanol solution by adding 12 g of NaOH into 100 mL of ethanol solution and stirring evenly.

[0056] Prepare chloroacetic acid / sodium acetate solution by adding 12 g chloroacetic acid to 5 mL ethanol solution, then add 2 g sodium acetate and stir well to complete the preparation.

[0057] Prepare potassium iodide / sodium acetate solution by adding 2g potassium iodide and 2g sodium acetate into 100ml distilled water and stirring evenly.

[0058] ② Preparation of CMC:

[0059] 4 g of cellulose was added to 150 mL of sodium hydroxide / ethanol solution, the mixture was stirred at 90 ° C for 120 min, 5 mL of chloroacetic acid / sodium acetate solution and 0.8 mL of potassium iodide / sodium acetate solution were added, and the reaction time was 110 min. Subsequently, 80 mL of sodium hydroxide / ethanol solution was added to the reactant and stirred for 120 min. Finally, the pH of the reactant was adjusted to 7 using 5% hydrochloric acid solution. The reactant was filtered and washed, and placed in a freeze dryer for freeze drying to obtain synthetic CMC.

[0060] Step 3, preparing liquid spraying membrane material:

[0061] Add 1g CMC to 50mL deionized water. After CMC is completely dissolved, add 50mL of 4% PVA aqueous solution to the CMC solution and mix thoroughly. Then, add 0.5% epoxy silane. Heat and stir at 60℃ for 120min to obtain a liquid spray film.

[0062] Embodiment effect test:

[0063] The liquid spray film prepared in Example 1 was used to spray the rapeseed siliques at the yellow ripe stage, and clean water spraying and blank were used as controls. After the spraying was dried, the siliques were sprayed again, and the process was repeated three times.

[0064] Before maturity, take 3 portions of siliques from each planting area, 20 in each portion, place them in a nylon net and hang them in a ventilated place to dry. After drying, use the random collision method to determine the anti-cracking angle coefficient. Specifically: place the siliques in a polyethylene plastic cylinder with an inner diameter of 13.4cm and a height of 20.5cm, and put in 2 stainless steel balls with a diameter of 20mm. The amplitude of the shaker is 24mm, the speed is 300r / min, shake for 1min, record the number of cracked siliques, and repeat this five times. Calculate the anti-cracking angle coefficient. The results are as follows: Figure 1 As shown by Figure 1 It can be seen that the angle crack resistance coefficient of the siliques in the empty bag control (CK) group is the worst. Spraying water (H) and spraying liquid spray film (LF) can both increase the angle crack resistance coefficient of the siliques. Compared with the H group, the angle crack resistance coefficient of the siliques in the LF group was significantly improved, indicating that spraying liquid spray film can significantly improve the crack resistance of rapeseed siliques.

[0065] Therefore, the present invention adopts the above-mentioned preparation method and application of a liquid spray film for improving the pod cracking resistance of rapeseed, forms a coating on the surface of the pod, improves the pod cracking resistance of rapeseed pods at different maturity stages by physical bonding, reduces the cracking and grain falling of pods during mechanical harvesting of rapeseed, and improves the adaptability of mechanical harvesting of rapeseed. At the same time, the liquid spray film is derived from straw-based biomass, the production process is green and safe, and will not affect the quality of rapeseed grains.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the technology and scope of the technical solution of the present invention.

Claims

1. A method for preparing a liquid spray film for improving the resistance of rapeseed to cracked corners, characterized in that: The following steps are involved: Step 1: extracting cellulose, adding 5% to 6% alkaline solution to the bio-straw, stirring and reacting at 80 to 150° C. for 0.5 to 4 hours, washing the filter residue with distilled water, and freeze-drying the filter residue to obtain cellulose; Step 2: Prepare CMC, add 4g of cellulose to 50-200mL of sodium hydroxide / ethanol solution, stir the mixture at 70-90°C for 60-120min; add 5-8mL of chloroacetic acid / sodium acetate solution and 0.5-1ml of potassium iodide / sodium acetate solution to react for 110-130min; then add 25-100mL of sodium hydroxide / ethanol solution and keep stirring for 60-120min; then, adjust the pH of the reactant to 6.0-7.0 using 5%-10% hydrochloric acid aqueous solution; filter the reactant, put the residue into a freeze dryer for freeze drying, and obtain CMC; Step 3: Prepare the liquid spray film, mix CMC and PVA thoroughly, then add the cross-linking agent and react at 60-70°C for 60-120 minutes.

2. The method for preparing a liquid spray film for improving the crack resistance of rapeseed according to claim 1, characterized in that: The biological straw in step 1 includes rice, corn, wheat, cotton, rape straw, bamboo powder or wood powder, and the particle size is 25-1000 mesh.

3. The method for preparing a liquid spray film for improving the crack resistance of rapeseed according to claim 1, characterized in that: In step 1, the ratio of biostraw to solution is 1:7-15 (w / w).

4. The method for preparing a liquid spray film for improving the crack resistance of rapeseed according to claim 1, characterized in that: In step 1, the alkaline solution is sodium hydroxide solution, sodium hydroxide / sodium chlorite solution, sodium hydroxide / hydrogen peroxide solution or sodium hydroxide / sodium chlorite solution.

5. The method for preparing a liquid spray film for improving the crack resistance of rapeseed according to claim 1, characterized in that: The mixing process of CMC and PVA in step 3 is as follows: 1-2 g of CMC is added to 50 mL of deionized water, and then 20-50 mL of 2%-5% PVA aqueous solution is added to the CMC solution and mixed evenly.

6. The method for preparing a liquid spray film for improving the crack resistance of rapeseed according to claim 1, characterized in that: In step 3, the crosslinking agent includes 0.5% to 5% of glutaraldehyde, 0.5% to 5% of citric acid and 0.2% to 2.0% of epoxy silane.

7. A liquid spray film for improving the resistance of rapeseed to corner cracking, which is prepared by the preparation method according to any one of claims 1 to 6.

8. Use of the liquid spraying film as claimed in claim 7 in improving the resistance of rapeseed to corner cracking.

9. A method for improving the resistance of rapeseed to horn cracking, characterized in that: The liquid spray film of claim 7 is used to spray the rapeseed siliques at the yellow ripe stage, and then sprayed again after the siliques are dried, and repeated three times to form a coating on the surface of the siliques.

Images