Herbicide for improving lodging resistance of rice and application thereof

Abstract

The invention relates to the technical field of herbicide preparation, in particular to a herbicide capable of improving lodging resistance of rice and application of the herbicide, and the herbicide comprises bispyribac-sodium microcapsules, a cell wall enhancer, a photosynthetic synergist, a quality improver, a nutritional agent, a surfactant, a polyglutamic acid-chitosan compound and water according to the mass ratio of (15-18): (18-23): (4-7): (4-7): (1.5-2): (0.5-1): (0.8-1.2): (100-150). Through a multi-component synergistic effect and an advanced preparation process, the core defects of an existing herbicide in the aspects of single function, environmental risk, short pesticide effect, nutrition deficiency and the like are systematically solved, and the technical highlight is that weeding, lodging resistance, nutrition supplement and environmental protection are deeply integrated.

Description

Technical Field

[0001] The present invention relates to the technical field of herbicide preparation, and particularly relates to a herbicide for improving the lodging resistance of rice and its application. Background Art

[0002] A herbicide, also known as a weed killer, is a chemical agent that can kill weeds or harmful plants without affecting the normal growth of crops. It can be used to control weeds in farmland or kill weeds or shrubs in non-agricultural cultivated land. According to its action characteristics, it can be divided into selective herbicides and non-selective herbicides. A selective herbicide refers to a herbicide that can selectively kill certain types of plants within a certain dose and concentration range, while being harmless to other types of plants.

[0003] However, the existing herbicides have the following technical problems: 1. Traditional herbicides take weed control as the core goal and lack comprehensive regulation of crop physiological functions, and cannot improve the lodging resistance of rice. For example, glyphosate, bispyribac-sodium, etc. are highly efficient in weed control, but long-term use may lead to weak crop stems and an increased risk of lodging. 2. Some herbicides contain strong chemical solvents or auxiliaries (such as organophosphorus), which may inhibit the photosynthesis of rice or damage the cell wall structure. For example, sulfonylurea herbicides will interfere with the plant hormone balance and cause the stems to be easily broken. 3. The surfactants (such as alkylbenzene sulfonates) or solvents in traditional formulations are difficult to degrade and are likely to pollute the soil and water bodies. Paraquat has been banned in many countries due to its high toxicity and residue problems. 4. The active ingredients of conventional formulations are prone to volatilization or photolysis, and need to be applied frequently, increasing the cost and labor intensity. For example, when the bispyribac-sodium technical is directly sprayed, it is easily washed away by rainwater and has a very short effective period. 5. Most herbicides do not integrate nutrient elements and cannot promote the healthy growth of crops synchronously. For example, after weeding, if rice lacks trace elements such as zinc and magnesium, its stress resistance will decrease significantly.

[0004] Therefore, it has become an urgent problem to provide a herbicide that can improve the lodging resistance of rice and is environmentally friendly. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a herbicide for improving the lodging resistance of rice and its application, which includes bispyribac-sodium microcapsules, cell wall strengthener, photosynthesis enhancer, quality improver, nutrient agent, surfactant, polyglutamic acid-chitosan complex and water, and the mass ratio is (15 - 18):(18 - 23):(4 - 7):(4 - 7):(1.5 - 2):(0.5 - 1):(0.8 - 1.2):(100 - 150).

[0006] Preferably, the mass ratio of the bispyribac-sodium microcapsules, cell wall strengthener, photosynthesis enhancer, quality improver, nutrient agent, surfactant, polyglutamic acid-chitosan complex and water is 17:20:5:6:1.5:0.5:1:100 - 150.

[0007] Preferably, the cell wall enhancer includes potassium silicate, calcium silicate, calcium chloride and citric acid, and the mass ratio is (8 - 10):(4 - 5):(6 - 8):(0.5 - 1). Most preferably, the mass ratio is 9:5:7:0.5.

[0008] Preferably, the photosynthesis enhancer includes magnesium L-ascorbate and lutein, and the mass ratio is (3 - 5):(1 - 2). Most preferably, the mass ratio is 4:1.

[0009] Preferably, the quality improver includes seaweed oligosaccharides and compound amino acids, and the mass ratio is (2 - 3):(2 - 4). Most preferably, the mass ratio is 2:3.

[0010] Preferably, the compound amino acids are L-glutamic acid and L-proline, and the mass ratio is 3:1.

[0011] Preferably, the nutrient includes one or more of humic acid chelated zinc, humic acid chelated iron and humic acid chelated magnesium. Most preferably, the mass ratio of humic acid chelated zinc, humic acid chelated iron and humic acid chelated magnesium is 1:1:1.

[0012] Preferably, the surfactant includes one or more of tea saponin, saponin, sucrose ester and rhamnolipid. Most preferably, the surfactant is sucrose ester and rhamnolipid, and the mass ratio is 1:2.

[0013] The preparation method of the herbicide includes the following steps:

[0014] Step 1, mix the surfactant, quality improver and water in proportion, and disperse at 2000 - 2500 rpm for 10 - 20 min;

[0015] Step 2, add the cell wall enhancer in proportion, keep the temperature at 40 - 45 °C, and stir at 100 - 120 rpm for 15 - 20 min;

[0016] Step 3, sequentially add the photosynthesis enhancer, nutrient, bispyribac-sodium microcapsule and polyglutamic acid-chitosan complex in proportion, and homogenize at 50 - 60 Mpa for 20 - 30 min to obtain the herbicide.

[0017] Preferably, the preparation method of the bispyribac-sodium microcapsule is to mix bispyribac-sodium with β-cyclodextrin, perform ultrasonic treatment at 40 - 50 °C and 40 - 50 kHz for 20 - 30 min, add a sodium alginate solution with a mass fraction of 0.1% - 0.2%, and perform spray drying with an inlet air temperature of 160 - 170 °C and an outlet air temperature of 80 - 90 °C to obtain the bispyribac-sodium microcapsule. Preferably, the mass ratio of bispyribac-sodium, β-cyclodextrin and sodium alginate solution is 1:3:10.

[0018] Preferably, the preparation method of the polyglutamic acid-chitosan complex is as follows: Mix a 1%-2% polyglutamic acid solution and a 0.5%-1% chitosan solution in a mass ratio of 3:2, at a temperature of 50-60°C, ultrasonic wave at 30-40 kHz for 20-25 minutes, at a temperature of -80--50°C, and dry at 10-20 Pa for 24 hours to obtain the polyglutamic acid-chitosan complex.

[0019] Preferably, mix potassium silicate, calcium silicate, calcium chloride and a 0.5% citric acid solution in proportion, stir at a constant temperature of 60°C until a transparent colloid is formed with a viscosity of 300-400 cP to obtain a cell wall strengthening agent.

[0020] The present invention has the following advantages:

[0021] 1. By adding components such as potassium silicate and calcium chloride, the mechanical strength of the stem is enhanced, and by adding components such as magnesium L-ascorbate, the light energy utilization rate is improved, promoting carbon accumulation, solving the drawback of traditional herbicides of "only removing without protecting", and significantly enhancing the lodging resistance.

[0022] 2. The present invention uses natural surfactants such as sucrose esters and rhamnolipids and biodegradable complexes such as polyglutamic acid-chitosan, without high-risk solvents, reducing ecological toxicity.

[0023] 3. The bispyribac-sodium microcapsule is embedded by β-cyclodextrin and spray-dried by sodium alginate, realizing slow release of the active ingredient, significantly improving the long-lasting effect period, and significantly reducing the application frequency.

[0024] 4. Humic acid chelated zinc, iron, and magnesium provide essential trace elements, and algal oligosaccharides activate the expression of crop stress-resistant genes, significantly improving the root activity of rice, and simultaneously enhancing the lodging resistance and disease resistance. Specific embodiments

[0025] The technical solutions in the embodiments of the invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0026] Example 1

[0027] The herbicide formulation is as follows:

[0028] The mass ratio of bispyribac-sodium microcapsule, cell wall strengthening agent, photosynthetic efficiency enhancer, quality improver, nutrient agent, surfactant, polyglutamic acid-chitosan complex and water is 17:20:5:6:1.5:0.5:1:100-150.

[0029] The cell wall enhancer includes potassium silicate, calcium silicate, calcium chloride and citric acid, with a mass ratio of 9:5:7:0.5.

[0030] The photosynthesis enhancer includes magnesium L-ascorbate and lutein, with a mass ratio of 4:1.

[0031] The quality improver includes seaweed oligosaccharides and compound amino acids, with a mass ratio of 2:3. The compound amino acids are L-glutamic acid and L-proline, with a mass ratio of 3:1.

[0032] The nutrient is humic acid chelated zinc, humic acid chelated iron and humic acid chelated magnesium, with a mass ratio of 1:1:1.

[0033] The surfactant is sucrose ester and rhamnolipid, with a mass ratio of 1:2.

[0034] The preparation method is as follows:

[0035] Step 1: Mix bispyribac-sodium with β-cyclodextrin at a temperature of 45°C, perform ultrasonic treatment at 45 kHz for 25 min, add a 0.1% sodium alginate solution, and perform spray drying with an inlet air temperature of 160 - 170°C and an outlet air temperature of 80 - 90°C to obtain bispyribac-sodium microcapsules. The mass ratio of bispyribac-sodium, β-cyclodextrin and sodium alginate solution is 1:3:10.

[0036] Step 2: Mix a 1% polyglutamic acid solution and a 0.5% chitosan solution in a mass ratio of 3:2, keep the temperature at 55°C, perform ultrasonic treatment at 35 kHz for 20 min, keep the temperature at -80°C, and dry at 10 Pa for 24 h to obtain a polyglutamic acid-chitosan complex.

[0037] Step 3: Mix potassium silicate, calcium silicate, calcium chloride and a 0.5% citric acid solution in proportion, and stir at a constant temperature of 60°C until a transparent colloid is formed with a viscosity of 300 cP to obtain the cell wall enhancer.

[0038] Step 4: Mix the surfactant, quality improver and water in proportion, and disperse at 2500 rpm for 15 min;

[0039] Step 5: Add the cell wall enhancer in proportion, keep the temperature at 42°C, and stir at 100 - 120 rpm for 20 min;

[0040] Step 6: Add the photosynthesis enhancer, nutrient, bispyribac-sodium microcapsules and polyglutamic acid-chitosan complex in proportion in sequence, and homogenize at 55 Mpa for 20 - 30 min to obtain the herbicide.

[0041] Test Example 1

[0042] A local paddy field was selected and evenly divided into several plots. It was divided into a control group and an experimental group, with 3 replicates in each group. The lodging rate of rice, rice yield, stem mechanical strength, biodegradation rate of herbicide, effective period, application frequency, weeding effect and soil residual toxicity were counted. The results are shown in Table 1.

[0043] Experimental group: The herbicide prepared in Example 1 was used, with a dosage of 35 mL per mu and diluted with 15 kg of water for spraying. The other field management methods (including the application time of herbicide) referred to "Green, High-quality and Efficient Rice Cultivation Technology", published by China Agricultural Science and Technology Press, edited by Wang Xinbing and He Jiuchun.

[0044] Control group: The field management methods completely followed "Green, High-quality and Efficient Rice Cultivation Technology", published by China Agricultural Science and Technology Press, edited by Wang Xinbing and He Jiuchun.

[0045] Table 1

[0046]

[0047] As can be seen from Table 1, the herbicide prepared by the present invention can significantly improve the lodging resistance of rice. By strengthening the stem with silicon and calcium and combining with a photosynthetic synergist to enhance carbon accumulation, the lodging rate is reduced to 5%-8%. The herbicide prepared by the present invention has good environmental protection properties, with natural surfactants (sucrose esters, rhamnolipids) and biodegradable carriers (polyglutamic acid-chitosan), and the biodegradation rate ≥ 90%. The herbicide prepared by the present invention can significantly extend the effective period and reduce the application cost. The microcapsule sustained-release technology of bispyribac-sodium extends the effective period to 45-60 days, and the application frequency per season is reduced by 60%-75%. The herbicide prepared by the present invention can also improve the quality of rice. Seaweed oligosaccharides and compound amino acids synergistically enhance the protein content of rice, and the yield per mu is increased by 15%-20%. The herbicide prepared by the present invention has no high-risk solvent residues, the soil recovers quickly, and it meets the requirements of green agriculture.

[0048] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A herbicide for improving the lodging resistance of rice, characterized in that: It includes bispyribac-sodium microcapsules, cell wall strengthener, photosynthetic enhancer, quality improver, nutrient, surfactant, polyglutamic acid-chitosan complex and water, with the mass ratio being (15-18):(18-23):(4-7):(4-7):(1.5-2):(0.5-1):(0.8-1.2):(100-150).

2. A herbicide for improving the lodging resistance of rice according to claim 1, characterized in that: The cell wall enhancer includes potassium silicate, calcium silicate, calcium chloride and citric acid, and the mass ratio is (8-10):(4-5):(6-8):(0.5-1).

3. The herbicide for improving the lodging resistance of rice according to claim 1, characterized in that: The photosynthetic synergist comprises L-ascorbic acid magnesium and lutein in a mass ratio of (3-5):(1-2).

4. The herbicide for improving the lodging resistance of rice according to claim 1, characterized in that: The quality improver includes seaweed oligosaccharides and complex amino acids in a mass ratio of (2-3):(2-4).

5. The herbicide for improving the lodging resistance of rice according to claim 1, characterized in that: The nutrient comprises one or more of humic acid chelated zinc, humic acid chelated iron and humic acid chelated magnesium.

6. The herbicide for improving the lodging resistance of rice according to claim 1, characterized in that: The surfactant includes one or more of tea saponin, saponin, sucrose ester and rhamnolipid.

7. The method for preparing the herbicide according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: Mix the surfactant, quality improver and water in proportion and disperse at 2000-2500rpm for 10-20min; Step 2: Add cell wall enhancer in proportion, stir at 40-45°C and 100-120 rpm for 15-20 min; Step 3, adding photosynthetic enhancer, nutrient, bispyribac-sodium microcapsule and polyglutamic acid-chitosan complex in proportion, homogenizing at 50-60 MPa for 20-30 minutes to obtain the herbicide.

8. The preparation method according to claim 7, characterized in that: The preparation method of the bispyribac-sodium microcapsules comprises: mixing bispyribac-sodium with β-cyclodextrin, subjecting the mixture to ultrasonic treatment at 40-50° C. and 40-50 kHz for 20-30 min, adding a sodium alginate solution having a mass fraction of 0.1%-0.2%, and spray drying at an inlet temperature of 160-170° C. and an outlet temperature of 80-90° C. to obtain bispyribac-sodium microcapsules; The mass ratio of the bispyribac-sodium, beta-cyclodextrin and sodium alginate solution is 1:3:

10.

9. The preparation method according to claim 7, characterized in that: The preparation method of the polyglutamic acid-chitosan complex comprises the following steps: mixing a polyglutamic acid solution with a mass fraction of 1%-2% and a chitosan solution with a mass fraction of 0.5%-1% at a mass ratio of 3:2, subjecting the mixture to ultrasonic treatment at 30-40kHz for 20-25min at a temperature of 50-60°C, and drying the mixture at 10-20pa for 24h to obtain the polyglutamic acid-chitosan complex.

10. Use of the herbicide according to any one of claims 1 to 9, characterized in that: Used for weeding in rice fields, use 30-40mL per mu and add 15-20kg of water for spraying.

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