Synthesis of novel plant growth regulator and application of novel plant growth regulator in improvement of crop stress resistance

Abstract

The invention discloses synthesis of a novel plant growth regulator and application of the novel plant growth regulator in improvement of crop stress resistance, and relates to the field of agricultural biology. The composition is composed of the following components in parts by weight: 10-20 parts of sodium alginate oligosaccharide; 30 to 50 parts of a functionalized polydopamine nano carrier PDA (at) Ce; 5 to 10 parts of yeast source defense peptide YDP-125; the chelating auxiliary agent comprises 2-5 parts of naphthylacetic acid potassium salt and 3-8 parts of fulvic acid. The synergistic effect of all the components is utilized, the sodium alginate oligosaccharide is used for activating an ethylene signal channel and starting stress-resistant gene expression, the yeast source defense peptide YDP-12 is used for simulating phytophyton, biosynthesis of jasmonic acid is stimulated, protein accumulation of PR-2 and PR-3 is promoted, virus resistance is enhanced, PDA at Ce is chelated with nutrients through phenolic hydroxyl groups, ROS response type cerium ion release is achieved, Fenton reaction is catalyzed, and the effect of improving stress resistance is achieved. The. OH is converted into H2O2; chelated Zn < 2 + > and Mn < 2 + > enhance the SOD activity, so that the content of membrane lipid peroxidation markers is reduced; fulvic acid and sodium alginate oligosaccharide form a complex, DNA methylation modification is continuously induced, and stress resistance phenotype maintenance is promoted.

Description

Technical Field

[0001] This invention belongs to the field of agricultural biology, specifically the synthesis of novel plant growth regulators and their application in improving crop stress resistance. Background Technology

[0002] In crop and vegetable production, plants frequently encounter abiotic stresses such as drought, salinity, and extreme temperatures, which severely affect their normal growth and development, ultimately leading to plant death and reduced yield. Based on improvements in plant varieties, techniques, and planting methods, the use of beneficial exogenous plant growth regulators to enhance plant stress resistance is of significant economic importance.

[0003] However, existing technologies still have the following problems: Traditional regulators such as paclobutrazol and chlormequat chloride, which are triazole retardants, control growth by inhibiting gibberellin synthesis, but have a long residual period, leading to a reduction of more than 30% in the emergence rate of subsequent crops and inhibiting fruit development. While biostimulants such as sodium alginate can activate antioxidant enzymes such as SOD and CAT, their large molecular structure (molecular weight >10kDa) makes it difficult to penetrate the plant epidermis, requiring high concentrations, resulting in high costs and unstable effects. Chemically synthesized regulators such as calcium cyclohexane require multi-step reactions involving toxic raw materials such as maleic anhydride, and have low yields; while furazolidone synthesis requires ultra-low temperatures of -70℃ and butyllithium, posing a high risk of explosion. Furthermore, existing products mostly target single stresses; beet regulators focus on salt-alkali stress, and 5-aminolevulinic acid mainly alleviates weak light stress, lacking synergistic protection against complex stresses. Biostimulants such as yeast peptides can induce disease resistance, but they are easily inactivated at room temperature and lack targeted delivery carriers, resulting in large fluctuations in field effects. Therefore, we propose the synthesis of novel plant growth regulators and their application in improving crop stress resistance, in order to solve the problems mentioned above.

[0004] The information disclosed above in this background section is only for enhancing the understanding of the background technology of this invention, and therefore may include prior art that is not known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide the synthesis of novel plant growth regulators and their application in improving crop stress resistance, so as to solve the problems in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a novel plant growth regulator, composed of the following components in parts by weight:

[0007] 10-20 parts of sodium alginate oligosaccharide;

[0008] Functionalized polydopamine nanocarrier PDA@Ce 30-50 parts;

[0009] Yeast-derived defensive peptide YDP-125 - 10 parts;

[0010] Chelating aids include 2-5 parts potassium naphthaleneacetate and 3-8 parts fulvic acid.

[0011] Preferably, the sodium alginate oligosaccharide has a molecular weight of <5000 Da and is obtained by degradation of alginate.

[0012] Preferably, the functionalized polydopamine nanocarrier PDA@Ce is polydopamine particles loaded with the rare earth element cerium, with a particle size of 80-120 nm.

[0013] Preferably, the yeast-derived defense peptide YDP-12 is an oligopeptide with a molecular weight of 1200 Da, derived from the enzymatic hydrolysate of Saccharomyces cerevisiae.

[0014] The synthesis method of the novel plant growth regulator described above includes the following steps:

[0015] Step 1: Preparation of sodium alginate oligosaccharides

[0016] Sodium alginate was prepared into a 5% aqueous solution and added to a 0.1 mol / L H2O2-Vc degradation system. The reaction was carried out at 60℃ for 3 h. The mixture was separated by ultrafiltration, with a molecular weight cutoff of 5000 Da. The product was then freeze-dried to obtain a white powder with a yield of ≥85%.

[0017] Step 2: Synthesis of polydopamine nanocarrier PDA@Ce

[0018] 2g of dopamine hydrochloride was dissolved in Tris-HCl buffer at pH 8.5, 0.5g of CeCl3 and 0.1g of H3BO3 were added, and the mixture was stirred at 40℃ for 12h to polymerize. The resulting black particles were obtained by centrifugation.

[0019] Step 3: Chelation Assembly

[0020] Dissolve 10g of sodium alginate oligosaccharide and 125g of yeast-derived defense peptide YDP-1 in deionized water, add 30g of PDA@Ce, and sonicate at 200W for 30min; add 3g / 50mL of potassium naphthaleneacetate ethanol solution and 5g of fulvic acid, and concentrate under reduced pressure at 45℃ into a paste; spray dry to obtain a brown powder with a moisture content of <5%.

[0021] Preferably, in step 1, the molar ratio of H2O2 to Vc is 1:1.

[0022] Preferably, in step 2, Ce 3+ and Ce 4+ The molar ratio was maintained at 1:0.2, as verified by XPS.

[0023] Preferably, in step 3, the spray drying inlet temperature is 120°C and the outlet temperature is 60°C.

[0024] Such as the application of the aforementioned novel plant growth regulators in improving crop stress resistance.

[0025] Preferably, the application refers to the use of plant growth regulators in improving the stress resistance of wheat, tomatoes, cotton, or sugar beets.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. This invention utilizes the synergistic effect of its components. Sodium alginate oligosaccharides activate the ethylene signaling pathway, initiating the expression of stress-resistance genes. Yeast-derived defense peptide YDP-12 mimics plant phylogenetics, stimulating jasmonic acid biosynthesis, promoting the accumulation of PR-2 and PR-3 proteins, and enhancing viral resistance. PDA@Ce chelates nutrients through phenolic hydroxyl groups, achieving ROS-responsive release of cerium ions, catalyzing the Fenton reaction to convert ·OH into H2O2; chelated Zn... 2+ and Mn 2+ It enhances SOD activity and reduces the content of membrane lipid peroxidation markers; fulvic acid and sodium alginate oligosaccharides form a complex that continuously induces DNA methylation modification and promotes the maintenance of stress-resistant phenotype.

[0028] 2. This invention uses boric acid-assisted polymerization to reduce the reaction temperature from 100℃ to 40℃. It utilizes the chelating effect of the catechol groups of polydopamine to achieve oriented loading of cerium ions, with a cerium loading rate of 95%. The entire reaction is carried out in an aqueous phase, avoiding the use of toxic solvents such as DMF and toluene, thus improving safety and environmental protection. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0030] Figure 1 This is a schematic diagram of the synthesis method of the present invention. Detailed Implementation

[0031] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0032] Example 1: Synthesis of Regulator

[0033] Prepare 15g of sodium alginate oligosaccharide, 8g of yeast-derived defense peptide YDP-12, 40g of PDA@Ce, 4g of potassium naphthaleneacetate, and 6g of fulvic acid.

[0034] Sodium alginate oligosaccharide and yeast-derived defense peptide YDP-12 were dissolved in 200 mL of water, PDA@Ce was added and ultrasonically dispersed, potassium naphthaleneacetate ethanol solution and fulvic acid were added, and the mixture was rotary evaporated at 45 °C until the solid content was 50%; the product was obtained by spray drying and stored in a sealed, light-proof container.

[0035] The following experimental data are based on multi-regional field trials conducted from 2023 to 2025, using a randomized block design with n=4 replicates and LSD test p<0.05.

[0036] Field Trial 1: Application of Wheat to Saline-Alkali Land Stress

[0037] Stress conditions: saline-alkali soil, pH 8.4, EC 5.8 dS / m.

[0038] Experimental groups: ① Water control group; ② Calcium silicon conditioner group; ③ Conditioner of this invention 2g / L.

[0039] Treatment plan: Spray once each during the wheat jointing stage and the booting stage, at a rate of 15 kg / mu.

[0040] The results of the measurements are shown in Table 1 below:

[0041] Table 1. Comparison of wheat yield components in saline-alkali land

[0042] index Group 1 Group 2 Group 3 Group ③ compared to Group ② Number of grains per ear 31.2±1.5 36.8±1.7* 42.5±2.0* Increased by 15.5% 1000-grain weight (g) 38.4±1.2 41.3±1.4* 42.8±1.3* Increased by 3.6% Effective ears of grain (10,000 / mu) 32.7±1.8 35.1±1.9* 39.6±2.2* An increase of 12.8% Yield per mu (kg) 402±19 492±22* 532±24* An increase of 8.1%. <![CDATA[Grain Na + (mg / kg)]]> 287±21 195±18* 106±9* Decrease of 45.6%

[0043] * indicates a significant difference from the control (p<0.05)

[0044] Field Trial 2: Application of High Temperature and Low Light Stress in Tomatoes

[0045] Stress conditions: high temperature for 5 days, low light with 60% light transmittance.

[0046] Experimental groups: ① control group with water; ② single application of ALO (20ppm); ③ single application of YDP-12 (10ppm); ④ regulator of the present invention at 5g / L.

[0047] Treatment plan: Drench the roots once when the seedlings have 3 leaves, using 50 mL per plant; foliar spray with 225 L / hm² on the 8th day after transplanting. 2 The high-temperature treatment lasted for 5 days, with daytime temperatures at 42°C and nighttime temperatures at 30°C.

[0048] The results of the measurements are shown in Table 2 below:

[0049] Table 2. Comparison of physiological and yield indicators of tomatoes under high temperature and low light stress

[0050]

[0051] * indicates a significant difference from the control (p<0.05)

[0052] Field Trial 3: Application of Drought Stress in Cotton

[0053] Stress conditions: drought, water control by rain shelter, soil moisture content of 8%.

[0054] Experimental groups: ① Water control group; ② Regulator of the present invention 1 g / L; ③ Regulator of the present invention 1.4 g / L; ④ Regulator of the present invention 2 g / L.

[0055] Treatment plan: Spray once each during the budding stage and the flowering and boll-forming stage, adding 0.1% organosilicon adjuvant. Spray at 18:00, using 450L / hm² of water. 2 .

[0056] The results of the measurements for each indicator are shown in Table 3 below:

[0057] Table 3. Comparison of key indicators for cotton under drought stress

[0058]

[0059] * indicates a significant difference from the control (p<0.05)

[0060] Field Trial 4: Application of Combined Stress of Salt-Alkali Diseases in Sugar Beet

[0061] Stress conditions: saline-alkali pH 8.2, EC 6.2 dS / m, root rot.

[0062] Experimental groups: ① Conventional treatment group; ② 1 g / L of the regulator of this invention.

[0063] Treatment plan: Spray once each at the 4-leaf stage, early tuber enlargement stage, and canopy closure stage (2.5 g / L), and inoculate with root rot pathogens simultaneously. The disease incidence rate was 35% in the control area. The routine treatment was calcium plus proline.

[0064] The results of the measurements for each indicator are shown in Table 4 below:

[0065] Table 4. Comparison of key indicators under combined stress of salt-alkali disease and pests in sugar beets

[0066]

[0067]

[0068] * indicates a significant difference from the control (p<0.05); Profit calculation: sugar price ¥5200 / ton

[0069] In summary, the regulator of this invention overcomes the limitations of existing technologies, such as calcium silicate agents that only enhance physical barriers and cephalosporins that only regulate hormones, by simultaneously activating antioxidant enzymes, osmotic regulation, and systemic resistance pathways, achieving synergistic protection against multiple stresses. The PDA@Ce nanocarrier enables ROS-responsive release, significantly improving cerium ion utilization and thus reducing dosage. Only 2-3 applications are needed throughout the entire growth cycle, compared to 4-6 applications with traditional methods, reducing costs per acre and offering both ease of application and economic benefits.

[0070] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A novel plant growth regulator, characterized in that, Composed of the following components in parts by weight: 10-20 parts of sodium alginate oligosaccharide; Functionalized polydopamine nanocarrier PDA@Ce 30-50 parts; Yeast-derived defensive peptide YDP-125 - 10 parts; Chelating aids include 2-5 parts potassium naphthaleneacetate and 3-8 parts fulvic acid.

2. The novel plant growth regulator according to claim 1, characterized in that: The sodium alginate oligosaccharide has a molecular weight of <5000 Da and is obtained by degradation of alginate.

3. The novel plant growth regulator according to claim 1, characterized in that: The functionalized polydopamine nanocarrier PDA@Ce consists of polydopamine particles loaded with the rare earth element cerium, with a particle size of 80-120 nm.

4. The novel plant growth regulator according to claim 1, characterized in that: The yeast-derived defense peptide YDP-12 is an oligopeptide with a molecular weight of 1200 Da, derived from the enzymatic hydrolysate of Saccharomyces cerevisiae.

5. The method for synthesizing the novel plant growth regulator according to any one of claims 1-4, characterized in that, Includes the following steps: Step 1: Preparation of sodium alginate oligosaccharides Sodium alginate was prepared into a 5% aqueous solution and added to a 0.1 mol / L H2O2-Vc degradation system. The reaction was carried out at 60℃ for 3 h. The mixture was separated by ultrafiltration, with a molecular weight cutoff of 5000 Da. The product was then freeze-dried to obtain a white powder with a yield of ≥85%. Step 2: Synthesis of polydopamine nanocarrier PDA@Ce 2g of dopamine hydrochloride was dissolved in Tris-HCl buffer at pH 8.5, 0.5g of CeCl3 and 0.1g of H3BO3 were added, and the mixture was stirred at 40℃ for 12h to polymerize. The resulting black particles were obtained by centrifugation. Step 3: Chelation Assembly Dissolve 10g of sodium alginate oligosaccharide and 125g of yeast-derived defense peptide YDP-1 in deionized water, add 30g of PDA@Ce, and sonicate at 200W for 30min; add 3g / 50mL of potassium naphthaleneacetate ethanol solution and 5g of fulvic acid, and concentrate under reduced pressure at 45℃ into a paste; spray dry to obtain a brown powder with a moisture content of <5%.

6. The method for synthesizing the novel plant growth regulator according to claim 5, characterized in that: In step 1, the molar ratio of H2O2 to Vc is 1:

1.

7. The method for synthesizing the novel plant growth regulator according to claim 5, characterized in that: In step 2, Ce 3+ and Ce 4+ The molar ratio was maintained at 1:0.2, as verified by XPS.

8. The method for synthesizing the novel plant growth regulator according to claim 5, characterized in that: In step 3, the spray drying inlet temperature is 120°C and the outlet temperature is 60°C.

9. The application of the novel plant growth regulator as described in any one of claims 1-4 in improving crop stress resistance.

10. The application according to claim 9, characterized in that: The application refers to the use of plant growth regulators to improve the stress resistance of wheat, tomatoes, cotton, or sugar beets.

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