A plant growth regulator composition for improving lodging resistance of wheat and use thereof

Abstract

The present application relates to the field of agricultural technology, in particular to a kind of plant growth regulator composition for improving wheat resistance to lodging and application thereof, made from the following components by weight parts: modified controlled-release microparticles, plant source growth promoter, adjuvant, deionized water;The composition of the present application is suitable for winter wheat varieties, and the spraying operation is simple, and can be used on leaf surface after dilution by 600 times, and the spraying liquid amount per mu is adapted to different vigor wheat fields, and has strong universality.Compared with the existing single water agent for controlling growth, simple compound regulator, the present application simultaneously solves many production problems such as short holding time of existing technology, weak effect of strong stem, low utilization rate of pesticide, easy to produce pesticide damage and other problems from multiple dimensions such as carrier slow release, cell wall physiological strengthening and leaf absorption synergism, and has significant industrial application value.

Description

Technical Field

[0001] This invention relates to the field of agricultural technology, specifically to a plant growth regulator composition for improving the lodging resistance of wheat and its application. Background Technology

[0002] Wheat lodging is a core production problem restricting stable wheat yield and quality improvement, especially in large-scale planting areas with sufficient water and fertilizer and high planting density. Wheat is susceptible to lodging due to wind and rain stress during the jointing to grain-filling stage. After lodging, the photosynthetic area of ​​the plants overlaps, ventilation and light penetration conditions deteriorate, the grain-filling process is hindered, the thousand-grain weight decreases, and mechanized harvesting losses increase significantly. In severe years, it can cause yield reductions of more than 20%. Currently, the mainstream lodging control methods in agricultural production mainly rely on spraying single plant growth retardants such as calcium cyclamate and paclobutrazol. However, existing technologies have many shortcomings in practical application.

[0003] First, conventional aqueous growth regulators lack sustained-release capabilities. After being sprayed onto wheat leaves, the solution is quickly washed away by dew and leached by rainwater during irrigation. The regulator's effect within the plant is short-lived, only inhibiting basal internode elongation for a short period after application. This leads to secondary excessive stem growth during the mid-to-late grain-filling stage, and the effective period for lodging resistance cannot cover the high-risk grain-filling phase. Increasing the concentration and frequency of application to compensate for this deficiency can inhibit ear differentiation, resulting in fewer grains per ear and more empty grains, making it difficult to achieve both increased yield and lodging resistance.

[0004] Secondly, existing lodging-resistant agents only focus on shortening the internode length of stems, lacking functional components that can enhance the mechanical strength of the stems themselves. The bending resistance of wheat stems is determined by the deposition of lignin in the cell walls and the enrichment of silicon. Simply relying on growth retardants can only change the internode length, failing to improve stem toughness and rigidity at the cell wall structure level. In strong convective weather, even plants with shorter internodes are still prone to bending and lodging. While some commercially available compound regulators contain silicon or brassinolide, the active components are simply physically mixed without a carrier to regulate the release rate. The absorption sequence of different active substances is mismatched, resulting in weak synergistic effects.

[0005] Third, conventional regulator systems lack compound adjuvants suitable for wheat leaf absorption. The waxy layer on the surface of wheat leaves is dense, resulting in poor wetting and spreading effects of simple aqueous solutions. Most of the solution rolls off and is lost, leading to low absorption and utilization rates of the active ingredients. Some products only add a single penetrant, which cannot simultaneously achieve the dual effects of prolonging the adhesion of the solution and promoting penetration across the waxy layer, resulting in low utilization efficiency and high production and usage costs.

[0006] Based on the shortcomings of existing technologies, such as short slow-release period, simple stem-strengthening mechanism, and low agent utilization, this invention proposes a plant growth regulator composition for improving wheat lodging resistance, solving various production and application problems existing in the prior art. Summary of the Invention

[0007] The purpose of this invention is to provide a plant growth regulator composition for improving the lodging resistance of wheat.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A plant growth regulator composition for improving wheat lodging resistance, comprising, by weight, the following components: 25-35 parts modified controlled-release microparticles, 12-18 parts plant-derived growth promoter, 8-15 parts adjuvant, and 40-55 parts deionized water.

[0010] As a further technical solution, the modified controlled-release microparticles are prepared by a method comprising the following steps:

[0011] (1) Preparation of amino-functionalized mesoporous silica core: 0.5g CTAB and 1.75mL 2mol / L sodium hydroxide solution were added to 200mL deionized water, stirred at 80℃ for 30min, and 2.5mL tetraethyl orthosilicate was added dropwise. The reaction was stirred continuously for 2h. The solid product was collected by centrifugation and the CTAB template agent was removed by high-temperature calcination to obtain mesoporous silica microspheres. 0.4-0.6g of mesoporous silica microspheres were dispersed in 100mL of ethanol / water mixed solution, where the volume ratio of ethanol to deionized water in the ethanol / water mixed solution was 3:1. The mixture was ultrasonically dispersed for 20-30min, and then 1.2-1.5mL ALAPTMS was added. The mixture was kept under an inert atmosphere and stirred at 55-60℃ for 5-6h. After the reaction, the mixture was centrifuged, washed with ethanol and water three times, and dried under vacuum to obtain amino-functionalized mesoporous silica core.

[0012] (2) Thermosensitive shell coating and quaternization modification: 0.5g of amino-functionalized core obtained in step (1) was ultrasonically dispersed in 100mL of acetic acid solution containing 1.0wt% chitosan and 0.2wt% sodium glycerophosphate. The pH of the system was controlled at 4.4-4.6, and the temperature was raised to 44-46℃. Glycidyl trimethylammonium chloride aqueous solution was added dropwise at a uniform rate. After the addition was completed, the reaction was carried out at a constant temperature for 3.5-4.5h. After the reaction was completed, the mixture was centrifuged at 8000r / min for 10min and washed twice with deionized water to remove unreacted monomers and residual impurities, and the modified particulate dispersion was obtained.

[0013] (3) Graded loading of active ingredients: Mix an aqueous solution of calcium cyclohexane with an equal volume of 10 g / L and the modified particulate dispersion from step (2), and impregnate by suction to uniformly load calcium cyclohexane into the mesoporous channels; then add a mixture of hydroxybrassinosteroids and potassium silicate, and stir for 1.5 to 2 hours at pH 5.0 to 5.5 and 20 to 25°C to obtain a particulate suspension;

[0014] (4) Drying and shaping: The microparticle suspension is placed in a vacuum freeze dryer, and after freeze drying and shaping, it is ground through a 200-mesh sieve to obtain the modified controlled-release microparticles.

[0015] As a further technical solution, the inert atmosphere in step (1) is nitrogen.

[0016] As a further technical solution, the uniform dripping of glycidyl trimethylammonium chloride aqueous solution in step (2) specifically involves uniformly dripping a 45% mass fraction glycidyl trimethylammonium chloride aqueous solution, with a dripping volume of 8-10 mL and a dripping rate of 1 mL / min.

[0017] As a further technical solution, the suction impregnation in step (3) is: suction impregnation for 30 minutes under a negative pressure of 0.08 to 0.09 MPa.

[0018] As a further technical solution, the freeze drying in step (4) is as follows: pre-freezing temperature -40℃, pre-freezing time 3h, vacuum degree 10Pa, and drying time 24h.

[0019] As a further technical solution, the plant-derived growth promoter is hydroxybrassinosteroidol and potassium silicate.

[0020] As a further technical solution, the hydroxybrassinosteroidol and potassium silicate are mixed in a molar ratio of 1:3 to 1:5 to prepare a mixed solution for use.

[0021] The concentration of hydroxybrassinosteroids in the mixture was 5 g / L.

[0022] As a further technical solution, the additive is composed of sodium lignosulfonate, ethylene glycol, and organosilicon penetrant SilwetL-77, with a weight ratio of 2:1:1.5.

[0023] The application of the plant growth regulator composition for improving wheat lodging resistance is described above. The composition is suitable for winter wheat varieties. It is applied evenly to the leaves of wheat from the early to mid-jointing stage. When applying, the composition is diluted with water 600 times per acre to prepare the spray solution. The amount of diluted solution applied per acre is 30-40 kg.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] The modified controlled-release microparticles in this invention serve as the core sustained-release carrier. This carrier uses amino-functionalized mesoporous silica as its core, coated with a temperature-sensitive quaternized chitosan shell. Internally, it is hierarchically loaded with calcium cyclohexane, hydroxybrassinosteroids, and potassium silicate. Because mesoporous silica possesses a rich pore structure, it can stably encapsulate high-content active ingredients. Amino modification enhances the binding force between the carrier and the active substances, preventing premature precipitation of components during storage. The temperature-sensitive outer shell changes the degree of pore opening and closing according to field temperature, allowing for slow release of the pesticide when the temperature is suitable during the wheat jointing stage. Hierarchical loading is achieved through a negative pressure suction impregnation process. Calcium cyclohexane is fixed in the deep pores for long-term sustained release, while hydroxybrassinosteroids and potassium silicate adhere to the shell region for rapid action. This achieves simultaneous supply of long-term growth control and immediate stem strengthening, thus solving the problem of ordinary pesticides' one-time release and insufficient duration of effect.

[0026] The plant-derived growth promoter uses a compound system of hydroxybrassinosteroids and potassium silicate. Hydroxybrassinosteroids can regulate the expression of genes related to wheat cell wall synthesis and promote the synthesis of lignin precursors. Potassium silicate can provide wheat with exogenous silicon, which is deposited in the stem cell wall to form a silicified fiber layer, increasing stem rigidity. When the two are compounded in a specific molar ratio, hydroxybrassinosteroids can promote the absorption and translocation of silicon in wheat roots and leaves. When potassium silicate is used alone, the plant's silicon absorption efficiency is low, and when hydroxybrassinosteroids is used alone, it cannot thicken the cell wall skeleton. The combination of the two can simultaneously enhance the dual processes of cell wall lignification and silicification at the molecular level, thereby compensating for the shortcomings of single growth retardants that only shorten internodes and cannot improve stem mechanical strength.

[0027] The compound adjuvant is formulated with sodium lignosulfonate, ethylene glycol, and organosilicon penetrant in a specific ratio. The organosilicon penetrant reduces the surface tension of the pesticide solution, breaks down the hydrophobic barrier of the waxy layer on wheat leaves, and enhances the spreading and penetration ability of the solution. Sodium lignosulfonate has high molecular weight adsorption properties, prolonging the adhesion time of the pesticide solution on the leaf surface and reducing rainwater runoff. Ethylene glycol acts as a moisturizer and solubilizer, preventing the precipitation of active components at low temperatures. These three adjuvants work synergistically in a fixed weight ratio, significantly improving the absorption and utilization rate of pesticides on leaves and solving the problems of easy rolling and low absorption efficiency of conventional regulators.

[0028] This invention confines modified controlled-release microparticles, plant-derived growth promoters, compound adjuvants, and deionized water within a specific weight range, forming a multi-level synergistic system: First, the modified controlled-release microparticles act as a carrier, simultaneously carrying two types of growth-promoting active substances, achieving a tiered release of the drug's effects. In the early stage, hydroxybrassinosteroids and potassium silicate released from the shell layer rapidly initiate stem strengthening, while in the mid-to-late stage, cyclic calcium sulfate released through pores continuously inhibits excessive internode growth. If the modified controlled-release microparticles are removed, the growth promoters and cyclic calcium sulfate, without carrier binding, will rapidly dissipate after spraying, completely eliminating the long-lasting stem-strengthening effect. Second, the compound adjuvant, modified controlled-release microparticles, and plant-derived growth promoters form an absorption synergy. The adjuvant enhances leaf penetration, allowing the active substances released by the controlled-release microparticles to quickly enter plant cells, amplifying the long-lasting benefits brought by the carrier's slow release. Without the compound adjuvant, even if the controlled-release microparticles continuously release active ingredients, most of the liquid cannot be absorbed by wheat, resulting in a significant reduction in the stem-strengthening effect. Furthermore, the combination of hydroxybrassinosteroids and potassium silicate as a growth promoter can amplify the lodging resistance of calcium cyclohexane. Calcium cyclohexane shortens the internodes and lowers the plant's center of gravity, while the growth promoter thickens the cell walls and enhances the stem's resistance to bending. The two work together to control length and increase strength, forming a double guarantee against lodging. If this combination system is missing, relying solely on calcium cyclohexane to control growth will result in insufficient stem toughness, making the stems prone to bending and lodging in windy weather.

[0029] Because this invention uses amino-mesoporous silica temperature-sensitive modified controlled-release microparticles as a slow-release carrier, combined with a plant-derived growth promoter of hydroxybrassinosteroids and potassium silicate, and supplemented with a special composite penetration aid, and with each component strictly limited in its ratio range, the entire composition can continue to exert its effect from the early jointing stage to the grain-filling stage of wheat after application. From a production perspective, on the one hand, it can effectively inhibit excessive elongation of the basal internodes of wheat, lowering the plant's center of gravity; on the other hand, it continuously promotes the deposition of lignin and silicon in the stem, significantly improving the stem's bending resistance and mechanical properties, and controlling the natural lodging rate in the field to within 3%. At the same time, the adjuvant system greatly improves the utilization rate of the pesticide, reduces the amount of pesticide used, lowers planting costs, and avoids the phytotoxicity to the ear development caused by high-concentration pesticides, thus balancing lodging resistance and increased wheat grain yield. The composition of this invention is suitable for winter wheat varieties, and the spraying operation is simple, requiring only a 600-fold dilution for foliar application. The spray volume range per acre is suitable for wheat fields with different growth levels, making it highly versatile. Compared with existing single growth regulators and simple compound regulators, this invention solves multiple production problems of existing technologies, such as short-lasting effect, weak stem strengthening effect, low pesticide utilization rate, and easy phytotoxicity, from multiple dimensions, including carrier slow release, cell wall physiological enhancement, and leaf absorption enhancement. It has significant industrial application value.

[0030] Instruction manual illustrations

[0031] Figure 1 This is a schematic diagram comparing the average lodging rate in the field of an example of a plant growth regulator composition for improving wheat lodging resistance with that of a comparative example. Detailed Implementation

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] This invention provides a plant growth regulator composition for improving the lodging resistance of wheat, which is made of the following components by weight: 25-35 parts of modified controlled-release microparticles, 12-18 parts of plant-derived growth promoter, 8-15 parts of adjuvant, and 40-55 parts of deionized water.

[0034] There are no special restrictions on the source of each raw material component in this invention. The modified controlled-release microparticles are prepared in-house according to the preparation process described in claim 2 of this invention. The plant-derived growth promoter, sodium lignosulfonate, ethylene glycol, organosilicon penetrant Silwet L-77, CTAB, 2mol / L sodium hydroxide solution, tetraethyl orthosilicate, APTMS, chitosan, sodium glycerophosphate, acetic acid, glycidyl trimethylammonium chloride, calcium cyclohexane, hydroxybrassinolide, and potassium silicate can all be commercially available industrial-grade raw materials from the agricultural chemical industry.

[0035] In this invention, the modified controlled-release microparticles are preferably 25-35 parts by weight, more preferably 28-32 parts by weight; the plant-derived growth promoter is preferably 12-18 parts by weight, more preferably 14-16 parts by weight; the adjuvant is preferably 8-15 parts by weight, more preferably 10-13 parts by weight; and the deionized water is preferably 40-55 parts by weight, more preferably 44-50 parts by weight.

[0036] The modified controlled-release microparticles of this invention are prepared by a method comprising the following steps:

[0037] (1) Preparation of amino-functionalized mesoporous silica core:

[0038] The mixture was prepared by adding 0.5 g CTAB and 1.75 mL 2 mol / L sodium hydroxide solution to every 200 mL deionized water, stirring at 80 °C for 30 min, then adding 2.5 mL tetraethyl orthosilicate dropwise, stirring continuously for 2 h, collecting the solid product by centrifugation, and calcining at high temperature to remove the CTAB template agent to obtain mesoporous silica microspheres. 0.4–0.6 g of the mesoporous silica microspheres were dispersed in 100 mL of an ethanol / water mixture with a volume ratio of ethanol to deionized water of 3:1, and ultrasonically dispersed for 20–30 min. Then, 1.2–1.5 mL of ALAPTMS was added, and the mixture was stirred at 55–60 °C under a nitrogen inert atmosphere for 5–6 h. After the reaction, the mixture was centrifuged, washed three times with ethanol and water, and vacuum dried to obtain amino-functionalized mesoporous silica cores.

[0039] In this step, the preferred amount of mesoporous silica microspheres is 0.4–0.6 g, more preferably 0.45–0.55 g; the preferred ultrasonic dispersion time is 20–30 min, more preferably 22–28 min; the preferred amount of APTMS added is 1.2–1.5 mL, more preferably 1.3–1.4 mL; the preferred reaction temperature is 55–60 °C, more preferably 56–59 °C; and the preferred reaction time is 5–6 h, more preferably 5.2–5.8 h.

[0040] (2) Temperature-sensitive shell coating and quaternization modification:

[0041] 0.5g of the amino-functionalized kernel obtained in step (1) was ultrasonically dispersed in 100mL of acetic acid solution containing 1.0wt% chitosan and 0.2wt% sodium glycerophosphate. The pH of the system was controlled at 4.4-4.6, and the temperature was raised to 44-46℃. A 45% glycidyltrimethylammonium chloride aqueous solution was added dropwise at a rate of 8-10mL at a rate of 1mL / min. After the addition was completed, the reaction was carried out at a constant temperature for 3.5-4.5h. After the reaction was completed, the mixture was centrifuged at 8000r / min for 10min and washed twice with deionized water to remove unreacted monomers and residual impurities, thus obtaining the modified particulate dispersion.

[0042] In this step, the pH of the system is preferably 4.4–4.6, more preferably 4.45–4.55; the reaction temperature is preferably 44–46℃, more preferably 44.5–45.5℃; the amount of glycidyl trimethylammonium chloride aqueous solution added is preferably 8–10 mL, more preferably 8.5–9.5 mL; and the isothermal reaction time is preferably 3.5–4.5 h, more preferably 3.8–4.2 h.

[0043] (3) Graded loading of active ingredients:

[0044] Mix an aqueous solution of calcium cyclohexane with an equal volume of 10 g / L and the modified particulate dispersion from step (2). Impregnate the mixture under a negative pressure of 0.08–0.09 MPa for 30 min to ensure that the calcium cyclohexane is uniformly loaded into the mesoporous channels. Then add a mixture of hydroxybrassinosteroids and potassium silicate and stir for 1.5–2 h at pH 5.0–5.5 and 20–25 °C to obtain a particulate suspension.

[0045] The hydroxybrassinosteroids and potassium silicate are mixed in a molar ratio of 1:3 to 1:5 to prepare a mixed solution for use, and the concentration of hydroxybrassinosteroids in the mixed solution is 5 g / L.

[0046] In this step, the suction impregnation negative pressure is preferably 0.08-0.09 MPa, more preferably 0.082-0.088 MPa; the reaction pH is preferably 5.0-5.5, more preferably 5.1-5.4; the reaction temperature is preferably 20-25℃, more preferably 21-24℃; the stirring time is preferably 1.5-2 h, more preferably 1.6-1.9 h; and the molar ratio of hydroxybrassinosteroidol to potassium silicate is preferably 1:3-1:5, more preferably 1:3.5-1:4.5.

[0047] (4) Drying and shaping:

[0048] The microparticle suspension was placed in a vacuum freeze dryer, pre-frozen at -40℃ for 3 hours, under a vacuum of 10 Pa for 24 hours, and then ground through a 200-mesh sieve to obtain the modified controlled-release microparticles.

[0049] The additive described in this invention consists of sodium lignosulfonate, ethylene glycol, and organosilicon penetrant Silwet L-77, in a weight ratio of 2:1:1.5. There is no specific order of preparation for the additive; it can be used after stirring and mixing evenly at room temperature.

[0050] The composition of this invention is suitable for winter wheat varieties. It should be sprayed evenly on the leaves from the early to mid-jointing stage of wheat. When applying, take the composition per acre and dilute it with water 600 times to prepare the spray solution. The amount of diluted solution per acre is 30-40 kg. The preferred amount of diluted solution is 30-40 kg, and more preferably 33-37 kg.

[0051] The plant growth regulator composition provided by this invention uses modified controlled-release microparticles as the core slow-release carrier, and is graded and loaded with multiple lodging-resistant active substances such as calcium cyclohexane, hydroxybrassinolide, and potassium silicate. Combined with a special plant-derived growth promoter and compound adjuvants, it can slowly and continuously release the active ingredients, shorten the length of the basal internodes of wheat, increase the deposition of lignin and silicon in the stem cell walls, improve the mechanical strength of wheat stems, and significantly reduce the lodging rate of wheat. The adjuvant system improves the adhesion and penetration efficiency of the liquid on the leaf surface, and reduces the loss due to rainwater erosion. The overall formula components have synergistic effects, a long-lasting effect, simple application process, no phytotoxicity to wheat growth, and are suitable for mainstream winter wheat varieties in China.

[0052] To further illustrate the technical solution of the present invention, three sets of embodiments and four sets of comparative examples are provided below for detailed explanation.

[0053] Example 1:

[0054] Step 1: Preparation of modified controlled-release microparticles:

[0055] 1.1 Preparation of amino-functionalized mesoporous silica core:

[0056] Take 200 mL of deionized water, add 0.5 g of CTAB, add 1.75 mL of 2 mol / L sodium hydroxide solution, and stir at 80 °C for 30 min. Add 2.5 mL of tetraethyl orthosilicate dropwise at a uniform rate, and continue stirring for 2 h. After the reaction, centrifuge to collect the solid product, and calcine at high temperature to remove the CTAB template agent to obtain mesoporous silica microspheres. Weigh 0.4 g of mesoporous silica microspheres and disperse them in 100 mL of ethanol / water mixed solution (ethanol to deionized water volume ratio 3:1), and sonicate for 20 min. Purge with nitrogen to maintain an inert atmosphere, add 1.2 mL of LAPTMS, and stir at 55 °C for 5 h. After the reaction, centrifuge, wash with ethanol and water three times, and vacuum dry to obtain amino-functionalized mesoporous silica cores.

[0057] 1.2 Temperature-sensitive shell coating and quaternization modification:

[0058] Weigh 0.5g of the amino-functionalized core obtained in step 1.1 and ultrasonically disperse it in 100mL of acetic acid solution containing 1.0wt% chitosan and 0.2wt% sodium glycerophosphate. Adjust the pH of the system to 4.4. Heat the solution to 44℃ and add 8mL of 45% glycidyltrimethylammonium chloride aqueous solution at a rate of 1mL / min. After the addition is complete, maintain the temperature at 44℃ for 3.5h. After the reaction is complete, centrifuge at 8000r / min for 10min and wash twice with deionized water to obtain the modified particulate dispersion.

[0059] 1.3 Graded loading of active ingredients:

[0060] Prepare a 10 g / L calcium cyclohexane aqueous solution and mix it with an equal volume of the particulate dispersion from step 1.2. Impregnate the mixture under a negative pressure of 0.08 MPa for 30 min. Prepare a mixture of hydroxybrassinosteroids and potassium silicate in a molar ratio of 1:3, with a hydroxybrassinosteroids concentration of 5 g / L. Add the mixture to the impregnated system, adjust the pH to 5.0, and stir at 20°C for 1.5 h to obtain a particulate suspension.

[0061] 1.4 Drying and setting:

[0062] The microparticle suspension was transferred into a vacuum freeze dryer, pre-frozen at -40℃ for 3 hours, under a vacuum of 10 Pa for 24 hours. After drying, the microparticles were ground and passed through a 200-mesh sieve to obtain modified controlled-release microparticles.

[0063] Step 2: Prepare the auxiliary agents:

[0064] Weigh the raw materials according to the weight ratio of sodium lignosulfonate: ethylene glycol: organosilicon penetrant SilwetL-77 = 2:1:1.5, stir and mix evenly at room temperature, and set aside.

[0065] Step 3: Prepare the plant growth regulator composition:

[0066] Weigh the raw materials according to the following proportions by weight: 25 parts modified controlled-release microparticles, 12 parts plant-derived growth promoter, 8 parts adjuvant, and 40 parts deionized water; stir the system at room temperature until all components are mixed evenly to obtain the plant growth regulator composition for improving wheat lodging resistance in this embodiment.

[0067] Step 4: Field application:

[0068] Select a winter wheat variety and spray the leaves at the early jointing stage of the wheat. Take the composition of this example per acre, dilute it with water 600 times to prepare a spray solution, and spray 30 kg of the diluted solution per acre evenly on the stems and leaves of the wheat plants.

[0069] Example 2:

[0070] Step 1: Preparation of modified controlled-release microparticles:

[0071] 1.1 Preparation of amino-functionalized mesoporous silica core:

[0072] Take 200 mL of deionized water, add 0.5 g of CTAB, add 1.75 mL of 2 mol / L sodium hydroxide solution, and stir at 80 °C for 30 min. Add 2.5 mL of tetraethyl orthosilicate dropwise at a uniform rate, and continue stirring for 2 h. After the reaction, centrifuge to collect the solid product, and calcine at high temperature to remove the CTAB template agent to obtain mesoporous silica microspheres. Weigh 0.6 g of mesoporous silica microspheres and disperse them in 100 mL of ethanol / water mixed solution (ethanol to deionized water volume ratio 3:1), and sonicate for 30 min. Purge with nitrogen to maintain an inert atmosphere, add 1.5 mL of ALAPTMS, and stir at 60 °C for 6 h. After the reaction, centrifuge, wash with ethanol and water three times, and vacuum dry to obtain amino-functionalized mesoporous silica cores.

[0073] 1.2 Temperature-sensitive shell coating and quaternization modification:

[0074] Weigh 0.5g of the amino-functionalized core obtained in step 1.1 and ultrasonically disperse it in 100mL of acetic acid solution containing 1.0wt% chitosan and 0.2wt% sodium glycerophosphate. Adjust the pH of the system to 4.6. Heat the solution to 46℃ and add 10mL of 45% glycidyltrimethylammonium chloride aqueous solution at a rate of 1mL / min. After the addition is complete, maintain the temperature at 46℃ for 4.5h. After the reaction is completed, centrifuge at 8000r / min for 10min and wash twice with deionized water to obtain the modified microparticle dispersion.

[0075] 1.3 Graded loading of active ingredients:

[0076] Prepare a 10 g / L calcium cyclohexane aqueous solution and mix it with an equal volume of the particulate dispersion from step 1.2. Impregnate the mixture under a negative pressure of 0.09 MPa for 30 min. Prepare a mixture of hydroxybrassinosteroids and potassium silicate in a molar ratio of 1:5, with a hydroxybrassinosteroids concentration of 5 g / L. Add the mixture to the impregnated system, adjust the pH to 5.5, and stir at 25°C for 2 h to obtain a particulate suspension.

[0077] 1.4 Drying and setting:

[0078] The microparticle suspension was transferred into a vacuum freeze dryer, pre-frozen at -40℃ for 3 hours, under a vacuum of 10 Pa for 24 hours. After drying, the microparticles were ground and passed through a 200-mesh sieve to obtain modified controlled-release microparticles.

[0079] Step 2: Prepare the auxiliary agents:

[0080] Weigh the raw materials according to the weight ratio of sodium lignosulfonate: ethylene glycol: organosilicon penetrant SilwetL-77 = 2:1:1.5, stir and mix evenly at room temperature, and set aside.

[0081] Step 3: Prepare the plant growth regulator composition:

[0082] Weigh the raw materials according to the following proportions by weight: 35 parts modified controlled-release microparticles, 18 parts plant-derived growth promoter, 15 parts adjuvant, and 55 parts deionized water; stir the system at room temperature until all components are mixed evenly to obtain the plant growth regulator composition for improving wheat lodging resistance in this embodiment.

[0083] Step 4: Field application:

[0084] Select winter wheat varieties and spray the leaves during the mid-jointing stage of wheat; take the composition of this example per acre, dilute it with water 600 times to prepare a spray solution, and spray 40 kg of the diluted solution per acre, evenly spraying the stems and leaves of wheat plants.

[0085] Example 3:

[0086] Step 1: Preparation of modified controlled-release microparticles:

[0087] 1.1 Preparation of amino-functionalized mesoporous silica core:

[0088] Take 200 mL of deionized water, add 0.5 g of CTAB, add 1.75 mL of 2 mol / L sodium hydroxide solution, and stir at 80 °C for 30 min. Add 2.5 mL of tetraethyl orthosilicate dropwise at a uniform rate, and continue stirring for 2 h. After the reaction, centrifuge to collect the solid product, and calcine at high temperature to remove the CTAB template agent to obtain mesoporous silica microspheres. Weigh 0.5 g of mesoporous silica microspheres and disperse them in 100 mL of ethanol / water mixed solution (ethanol to deionized water volume ratio 3:1), and sonicate for 25 min. Purge with nitrogen to maintain an inert atmosphere, add 1.35 mL of ALAPTMS, and stir at 58 °C for 5.5 h. After the reaction, centrifuge, wash with ethanol and water three times, and vacuum dry to obtain amino-functionalized mesoporous silica cores.

[0089] 1.2 Temperature-sensitive shell coating and quaternization modification:

[0090] Weigh 0.5g of the amino-functionalized core obtained in step 1.1 and ultrasonically disperse it in 100mL of acetic acid solution containing 1.0wt% chitosan and 0.2wt% sodium glycerophosphate. Adjust the pH of the system to 4.5. Heat the solution to 45℃ and add 9mL of 45% glycidyltrimethylammonium chloride aqueous solution at a rate of 1mL / min. After the addition is complete, maintain the temperature at 45℃ for 4h. After the reaction is completed, centrifuge at 8000r / min for 10min and wash twice with deionized water to obtain the modified particulate dispersion.

[0091] 1.3 Graded loading of active ingredients:

[0092] Prepare a 10 g / L calcium cyclohexane aqueous solution and mix it with an equal volume of the particulate dispersion from step 1.2. Impregnate the mixture under a negative pressure of 0.085 MPa for 30 min. Prepare a mixture of hydroxybrassinosteroids and potassium silicate in a molar ratio of 1:4, with a hydroxybrassinosteroids concentration of 5 g / L. Add the mixture to the impregnated system, adjust the pH to 5.2, and stir at 22°C for 1.8 h to obtain a particulate suspension.

[0093] 1.4 Drying and setting:

[0094] The microparticle suspension was transferred into a vacuum freeze dryer, pre-frozen at -40℃ for 3 hours, under a vacuum of 10 Pa for 24 hours. After drying, the microparticles were ground and passed through a 200-mesh sieve to obtain modified controlled-release microparticles.

[0095] Step 2: Prepare the auxiliary agents:

[0096] Weigh the raw materials according to the weight ratio of sodium lignosulfonate: ethylene glycol: organosilicon penetrant SilwetL-77 = 2:1:1.5, stir and mix evenly at room temperature, and set aside.

[0097] Step 3: Prepare the plant growth regulator composition:

[0098] Weigh the raw materials according to the following parts by weight: 30 parts of modified controlled-release microparticles, 15 parts of plant-derived growth promoter, 11 parts of adjuvant, and 48 parts of deionized water; stir the system at room temperature until all components are mixed evenly to obtain the plant growth regulator composition for improving wheat lodging resistance in this embodiment.

[0099] Step 4: Field application:

[0100] Select a winter wheat variety and spray the leaves at the early stage of wheat jointing; take the composition of this example per acre, dilute it with water 600 times to prepare a spray solution, and spray 35 kg of diluted solution per acre, evenly spraying the stems and leaves of wheat plants.

[0101] Comparative Example 1:

[0102] The overall formula is consistent with the basic ratio of Example 3, the only difference being that no modified controlled-release microparticles are added and the total weight of deionized water is adjusted to make up the difference; the types and ratios of other plant-derived growth promoters and adjuvants remain unchanged; there is no modified controlled-release microparticle preparation process, and the raw materials are directly mixed to formulate the regulator.

[0103] By weight: 15 parts plant-derived growth promoter, 11 parts adjuvant, and 78 parts deionized water, mixed evenly at room temperature.

[0104] The field application method is exactly the same as in Example 3.

[0105] Comparative Example 2:

[0106] The preparation process, auxiliary agent ratio, and basic weight parts of the modified controlled-release microparticles are the same as in Example 3; the difference is that no plant-derived growth promoter is added, and deionized water is used to make up the parts; the formula weight parts are: 30 parts of modified controlled-release microparticles, 11 parts of auxiliary agent, and 63 parts of deionized water.

[0107] The field application method is exactly the same as in Example 3.

[0108] Comparative Example 3:

[0109] The modified controlled-release microparticle preparation process, the ratio of plant-derived growth promoter, and the basic weight parts are the same as in Example 3; the difference is that no adjuvants are added, and deionized water is used to make up the parts; the formula weight parts are: 30 parts of modified controlled-release microparticles, 15 parts of plant-derived growth promoter, and 59 parts of deionized water.

[0110] The field application method is exactly the same as in Example 3.

[0111] Comparative Example 4:

[0112] Commercially available 20% calcium cyclohexane aqueous solution is free of amino-mesoporous silica temperature-sensitive controlled-release microparticles, hydroxybrassinolide potassium silicate compound growth promoter, and compound penetration aid. For field application, refer to the application period in Example 3, dilute 600 times according to the recommended dosage on the market, and spray with 35 kg of spray solution per acre.

[0113] Experiment 1: Determination of the bending resistance of wheat basal stems at three points during bending.

[0114] I. Experimental Instruments:

[0115] Electronic universal testing machine (CMT2103, MITES Industrial), matching three-point bending fixture, digital display vernier caliper (accuracy 0.01mm), electronic balance (accuracy 0.001g), and drying oven.

[0116] II. Experimental Procedures:

[0117] Sampling period: mid-grain filling stage of wheat (high lodging window). 20 disease-free and uniformly growing wheat plants were randomly selected from each plot. The second internode at the base of the plant (the key internode for lodging stress) was cut off, the surface dust was wiped off with clean water, and the plant was air-dried at room temperature for 2 hours to remove surface free moisture.

[0118] Size measurement: Use vernier calipers to measure the outer diameter and wall thickness at the middle of each internode, and record the cross-sectional dimensions of the stem.

[0119] Three-point bending test: The span of the clamp support is fixed at 30mm, the downward loading rate of the pressure head is 2mm / min, and the pressure head is pressed down at a constant speed until the stem breaks. The equipment automatically records the maximum load at the moment of breakage, which is the bending resistance of a single stem, in N. Each stem is tested only once to avoid repeated bending that could cause damage and interfere with the data.

[0120] Data processing: The arithmetic mean of 20 data points in each plot was taken, and the mean of the three repeated plots was used as the final result of the processing.

[0121] III. Experimental Data:

[0122] Table 1. Average bending resistance of wheat basal second internode under different treatments.

[0123] Example 1 14.3 Example 2 14.8 Example 3 15.1 Comparative Example 1 9.2 Comparative Example 2 10.5 Comparative Example 3 11.3 Comparative Example 4 8.7

[0124] The stem bending resistance of the three sets of examples was significantly higher than that of all comparative examples.

[0125] Comparative Example 1 without modified controlled-release microparticles: Calcium cyclohexane and potassium silicate have no slow-release carrier. After spraying, they are washed away by rainwater and quickly lost from the leaves. The wheat stems do not continuously obtain active substances, resulting in longer internodes at the base, thinner cell walls, and a significant decrease in mechanical strength.

[0126] Comparative Example 2 lacks the hydroxybrassinosteroid + potassium silicate compound growth-promoting system: relying solely on calcium cyclohexane to shorten internodes cannot induce stem silica deposition or promote lignin synthesis, resulting in limited improvement in stem toughness;

[0127] Comparative Example 3: Without the compound penetration aid SilwetL-77 and sodium lignosulfonate: the leaf surface wetting and penetration ability of the liquid is poor, a large amount of the agent remains on the leaf surface and cannot be absorbed, the uptake of effective ingredients is low, and the stem strengthening effect is weaker than that of the complete formula.

[0128] Comparative Example 4: Commercially available common calcium cyclohexane aqueous solution: without sustained-release structure, without silicon source and compounded with brassinolide, the efficacy period is short, the stems grow rapidly in the middle and late stages, and the bending strength is the lowest among all groups.

[0129] Experiment 2: Field survey of natural lodging rate of wheat at maturity:

[0130] I. Experimental Methods:

[0131] Survey period: Late waxy maturity stage of wheat, 3 days after wind and rain to carry out lodging statistics; Lodging judgment criteria: Wheat plant stem tilt angle > 45°, and the base is bent and cannot recover to upright on its own, is judged as a lodged single plant.

[0132] Statistical process: The total number of plants and the number of lodged plants are counted manually row by row in each plot; the lodging rate is calculated as follows: lodging rate = number of lodged plants / total number of plants in the plot × 100%; the average lodging rate is calculated from 3 replicate plots.

[0133] Environmental uniformity: The experimental area experienced two moderate wind and rain weather events during the grouting period, ensuring uniform lodging stress conditions and fair comparison among the groups.

[0134] II. Experimental Data:

[0135] Table 2. Average lodging rate of wheat at maturity under different treatments

[0136] Example 1 3.1 Example 2 2.7 Example 3 2.4 Comparative Example 1 18.5 Comparative Example 2 14.3 Comparative Example 3 11.6 Comparative Example 4 21.4

[0137] The lodging rate in all three sets of examples was less than 3.2%, demonstrating excellent lodging resistance in the field.

[0138] Comparative Example 1 lacks modified controlled-release microparticles: the agent has a short-term onset of action but quickly becomes ineffective, resulting in secondary excessive growth of basal internodes in the late grain-filling stage of wheat, insufficient stem strength, and a significantly increased risk of lodging;

[0139] Comparative Example 2: Silicon-free brassinolide growth-promoting compound: The stem cell walls have a low degree of silicification and poor toughness, making them extremely prone to bending and lodging in strong winds;

[0140] Comparative Example 3 without penetrating adjuvant: The absorption and utilization rate of the pesticide solution was low, the accumulation of active substances for strengthening the stem inside the plant was insufficient, and the lodging resistance was moderate to weak.

[0141] Comparative Example 4: The conventional aqueous formulation had no sustained-release effect and no silicon supplementation. It only inhibited internode elongation in the short term. After the efficacy of the drug wore off, the lodging was the most severe, and the lodging rate was the highest among all groups.

[0142] Experiment 3: Determination of lignin and silicon content in wheat stalks:

[0143] I. Experimental Instruments:

[0144] Electric constant temperature drying oven, high-speed multi-functional pulverizer, 80-mesh standard sample sieve, microwave digester, inductively coupled plasma optical emission spectrometer (ICP-OES), ultraviolet-visible spectrophotometer, constant temperature water bath, centrifuge.

[0145] II. Experimental Procedures:

[0146] Pre-sampling treatment: During the mid-grouting stage, 10g of wheat basal stems were randomly cut from each plot, rinsed three times with deionized water to remove residual agents on the surface, dried at 65℃ to constant weight, crushed and passed through an 80-mesh sieve, sealed and stored in the dark for testing.

[0147] Lignin content determination (sulfuric acid hydrolysis-spectrophotometry, a general method for plant fiber detection): Take 0.2g of stem powder, hydrolyze with 72% concentrated sulfuric acid at room temperature for 2h, dilute with water, reflux in a boiling water bath for 4h, filter and collect insoluble lignin, dissolve in alkali and measure absorbance at 280nm wavelength, convert the percentage of lignin in the dry stem mass according to the standard curve; 3 parallel samples per group.

[0148] Silicon content determination (microwave digestion-ICP-OES method, standard method for plant silicon detection): Weigh 0.1g of stem powder, digest it in a nitric acid-hydrofluoric acid system using microwave, and after adjusting the volume, test the silicon concentration using an instrument. Convert the concentration to milligrams of silicon per gram of dry stem (mg / g); 3 parallel samples per group.

[0149] III. Experimental Data:

[0150] Table 3. Accumulation of lignin and silicon in wheat dry stalks

[0151] Example 1 12.4 4.9 Example 2 12.8 5.1 Example 3 13.1 5.4 Comparative Example 1 8.3 2.1 Comparative Example 2 9.4 2.9 Comparative Example 3 10.2 3.4 Comparative Example 4 7.9 1.8

[0152] Lignin and silicon are the core substances for enhancing the rigidity and toughness of wheat stem cell walls. In the example, both groups of indicators were significantly better than the comparative example. The modified controlled-release microparticles can slowly and continuously release calcium cyclohexanoate and potassium silicate, continuously inducing wheat lignin synthesis and silicon deposition in the cell wall; hydroxybrassinosteroids can regulate the cell wall synthesis pathway and synergistically enhance the stem-strengthening effect.

[0153] Comparative Example 1 without sustained-release carrier: Short-term interruption of silicon and calcium cyclohexane supply resulted in the lowest degree of lignification and silicification of the stems;

[0154] Comparative Example 2: Potassium silicate and hydroxybrassinosteroids were missing. Due to the lack of exogenous silicon supply and the absence of brassinosteroids to regulate cell wall development, the amount of silicon deposition decreased significantly.

[0155] Comparative Example 3 lacked penetration enhancers: the total amount of active components absorbed by the plants was insufficient, and the increase in lignin synthesis was limited;

[0156] Comparative Example 4: The conventional aqueous solution lacks a silicon source and a slow-release system, and cannot continuously supply the substances that strengthen the stems. The lignin and silicon content in the stems is the lowest among all groups.

[0157] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not describe all details exhaustively, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification.

Claims

1. A plant growth regulator composition for improving lodging resistance in wheat, characterized in that, It is made from the following components by weight: 25-35 parts modified controlled-release microparticles, 12-18 parts plant-derived growth promoter, 8-15 parts adjuvants, and 40-55 parts deionized water.

2. The plant growth regulator composition for improving lodging resistance in wheat according to claim 1, characterized in that, The modified controlled-release microparticles are prepared by a method comprising the following steps: (1) Preparation of amino-functionalized mesoporous silica core: 0.5g CTAB and 1.75mL 2mol / L sodium hydroxide solution were added to 200mL deionized water, stirred at 80℃ for 30min, 2.5mL tetraethyl orthosilicate was added dropwise, and the reaction was stirred continuously for 2h. The solid product was collected by centrifugation, and the CTAB template agent was removed by high-temperature calcination to obtain mesoporous silica microspheres. 0.4–0.6 g of mesoporous silica microspheres were dispersed in 100 mL of an ethanol / water mixed solution with a volume ratio of ethanol to deionized water of 3:

1. The mixture was ultrasonically dispersed for 20–30 min, followed by the addition of 1.2–1.5 mL of ALAPTMS. The reaction was carried out under an inert atmosphere and stirred at a constant temperature of 55–60 °C for 5–6 h. After the reaction was completed, the mixture was centrifuged, washed three times with ethanol and water, and vacuum dried to obtain amino-functionalized mesoporous silica cores. (2) Thermosensitive shell coating and quaternization modification: 0.5g of amino-functionalized core obtained in step (1) was ultrasonically dispersed in 100mL of acetic acid solution containing 1.0wt% chitosan and 0.2wt% sodium glycerophosphate. The pH of the system was controlled at 4.4-4.6, and the temperature was raised to 44-46℃. Glycidyl trimethylammonium chloride aqueous solution was added dropwise at a uniform rate. After the addition was completed, the reaction was carried out at a constant temperature for 3.5-4.5h. After the reaction was completed, the mixture was centrifuged at 8000r / min for 10min and washed twice with deionized water to remove unreacted monomers and residual impurities, and the modified particulate dispersion was obtained. (3) Graded loading of active ingredients: Mix an aqueous solution of calcium cyclohexane with an equal volume of 10 g / L and the modified particulate dispersion from step (2), and impregnate by suction to uniformly load calcium cyclohexane into the mesoporous channels; then add a mixture of hydroxybrassinosteroids and potassium silicate, and stir for 1.5 to 2 hours at pH 5.0 to 5.5 and 20 to 25°C to obtain a particulate suspension; (4) Drying and shaping: The microparticle suspension is placed in a vacuum freeze dryer, and after freeze drying and shaping, it is ground through a 200-mesh sieve to obtain the modified controlled-release microparticles.

3. The plant growth regulator composition for improving lodging resistance in wheat according to claim 2, characterized in that, The inert atmosphere mentioned in step (1) is nitrogen.

4. The plant growth regulator composition for improving lodging resistance in wheat according to claim 1, characterized in that, The uniform dripping of glycidyltrimethylammonium chloride aqueous solution in step (2) specifically refers to the uniform dripping of a 45% mass fraction glycidyltrimethylammonium chloride aqueous solution, with a dripping volume of 8-10 mL and a dripping rate of 1 mL / min.

5. The plant growth regulator composition for improving lodging resistance in wheat according to claim 1, characterized in that, The suction impregnation in step (3) is performed by suction impregnation for 30 minutes under a negative pressure of 0.08 to 0.09 MPa.

6. The plant growth regulator composition for improving lodging resistance in wheat according to claim 1, characterized in that, The freeze-drying process described in step (4) is as follows: pre-freezing temperature -40℃, pre-freezing time 3h, vacuum degree 10Pa, and drying time 24h.

7. The plant growth regulator composition for improving lodging resistance of wheat according to claim 1, characterized in that, The plant-derived growth promoter is hydroxybrassinosteroidol and potassium silicate.

8. A plant growth regulator composition for improving lodging resistance in wheat according to claim 7, characterized in that, The hydroxybrassinosteroidol and potassium silicate are mixed in a molar ratio of 1:3 to 1:5 to prepare a mixed solution for use. The concentration of hydroxybrassinosteroids in the mixture was 5 g / L.

9. A plant growth regulator composition for improving lodging resistance in wheat according to claim 1, characterized in that, The additive consists of sodium lignosulfonate, ethylene glycol, and organosilicon penetrant in a weight ratio of 2:1:1.

5.

10. The application of a plant growth regulator composition for improving lodging resistance in wheat according to any one of claims 1 to 9, characterized in that, The composition is suitable for winter wheat varieties. It should be sprayed evenly on the leaves from the early to mid-jointing stage of wheat. When applying, take the composition per acre and dilute it with water 600 times to prepare the spray solution. The amount of diluted solution per acre should be 30-40 kg.

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