A rice cadmium reduction foliar control agent and its application method

Abstract

The invention discloses a rice cadmium-reducing foliar barrier and an application method thereof. The cadmium-reducing foliar barrier is prepared by compounding rice husk wood vinegar, sodium silicate and zinc sulfate, wherein the mass ratio is 15%-20% of sodium silicate, 10%-15% of zinc sulfate and the remainder is rice husk wood vinegar. The cadmium-reducing foliar barrier is sprayed at the tillering stage and the booting stage of rice respectively. Compared with spraying an equal amount of clear water and a rice cadmium-reducing foliar barrier of other formulas, the cadmium-reducing foliar barrier of the invention significantly reduces the cadmium content in rice brown rice, is simple to operate, and raw materials are easy to obtain, and waste is turned into treasure. Several barrier components cooperate with each other to jointly play the role of reducing cadmium in rice, and have a strong prospect for promotion and application.

Description

Technical Field

[0001] The invention relates to the technical field of agriculture, and in particular to a rice cadmium-reducing foliar barrier and an application method thereof. Background Art

[0002] Rice is an important global food resource, providing the main source of calories for more than 50% of the world's population. Rice requires a large number of elements such as nitrogen, phosphorus, and potassium during its growth, as well as trace elements such as silicon, magnesium, boron, and cadmium. Although these trace elements account for a small proportion of all the elements required for the rice growth cycle, they play an important role in the growth and development of rice.

[0003] Rice is the largest crop planted in China and an important source of food for China. Cadmium (Cd) is one of the most biologically toxic heavy metals and is currently the most common heavy metal pollution element in my country's cultivated land, with a point-to-point exceeding rate of up to 7%. Rice is very easy to accumulate heavy metal cadmium and is the major cereal crop with the strongest ability to absorb cadmium. It also poses a potential threat to human health through the food chain. Rice has become the main source of heavy metal cadmium intake for the human body. Cadmium is a non-essential element for the human body and is toxic to humans, animals and plants. Long-term low-dose cadmium exposure caused by eating "cadmium rice" has the triple effects of carcinogenicity, teratogenicity and mutagenicity, which seriously threatens food production safety and human health.

[0004] In order to reduce the risk of cadmium pollution in rice to human health, my country's food safety standard (GB2762-2012) stipulates that the limit of cadmium in rice is 0.2 mg kg -1 .

[0005] Therefore, how to provide a foliar inhibitor for reducing cadmium in rice and an application method thereof is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0006] The invention aims to overcome the disadvantages of the prior art and provides a rice cadmium-reducing foliar barrier and an application method thereof. The cadmium-reducing foliar barrier is prepared by compounding rice husk wood vinegar, sodium silicate and zinc sulfate, wherein the mass ratio is 15%-20% of sodium silicate, 10%-15% of zinc sulfate and the remainder is rice husk wood vinegar. The cadmium-reducing foliar barrier is sprayed at the tillering stage and the booting stage of rice respectively. Compared with spraying an equal amount of clear water and a rice cadmium-reducing foliar barrier of other formulas, the cadmium-reducing foliar barrier of the invention significantly reduces the cadmium content in rice brown rice, is simple to operate, and raw materials are easily available, and waste is turned into treasure. Several barrier components cooperate with each other to jointly play the role of reducing cadmium in rice, and have a strong prospect for promotion and application.

[0007] In order to achieve the above technical effects, the following technical solutions are adopted:

[0008] A rice cadmium reduction foliar control agent comprises the following components:

[0009] Husk wood vinegar, sodium silicate, zinc sulfate;

[0010] Further, the preparation method of the rice husk wood vinegar is:

[0011] In the drying stage, the temperature is 20-60°C, during which the rice is completely dried;

[0012] In the hulling stage, the husk is separated from the brown rice by a rice mill;

[0013] In the fermentation stage, the husks are piled up for fermentation, and the fermentation temperature is controlled at 70-150°C. During this process, the husks begin to decompose, and the gaseous wood vinegar components produced in this process are cooled and recovered by a condenser to form a wood vinegar stock solution;

[0014] Separation and refining: The wood vinegar stock solution is collected and stored in a sedimentation tank, and is separated and refined by standing for more than 3 months to obtain the entire wood vinegar stock solution.

[0015] Furthermore, the mass ratio of the rice husk wood vinegar, sodium silicate and zinc sulfate is:

[0016] Sodium silicate 15%-20%, zinc sulfate 10%-15%, and the balance is rice husk wood vinegar.

[0017] A method for applying a rice cadmium-reducing foliar inhibitor comprises the following steps:

[0018] The sodium silicate and zinc sulfate in the rice cadmium-reducing foliar control agent are dissolved in proportion in the rice husk wood vinegar solution, and the mixture is evenly mixed to obtain the foliar control agent, which is then diluted with a diluent and sprayed evenly on the rice leaves during the rice growth process.

[0019] Furthermore, the diluent of the foliar barrier agent is water.

[0020] Furthermore, the dilution multiple of the foliar barrier agent is 500-800 times.

[0021] Furthermore, the rice growth process is the tillering stage and / or the booting stage.

[0022] Furthermore, the dosage of the foliar barrier agent before dilution is 3-4 L / hectare.

[0023] Furthermore, the foliar barrier agent is sprayed before 10 am and after 4 pm on a sunny or cloudy day, the suitable temperature range is 15-30°C, and the spraying site is the rice leaf surface.

[0024] Furthermore, the foliar barrier agent is sprayed 1-3 times during the tillering stage and the booting stage.

[0025] The beneficial effects of the present invention are:

[0026] The invention discloses a rice cadmium-reducing foliar barrier and an application method thereof. The cadmium-reducing foliar barrier is prepared by compounding rice husk wood vinegar, sodium silicate and zinc sulfate, wherein the mass ratio is 15%-20% of sodium silicate, 10%-15% of zinc sulfate and the remainder is rice husk wood vinegar. The cadmium-reducing foliar barrier is sprayed at the tillering stage and the booting stage of rice respectively. Compared with spraying an equal amount of clear water and a rice cadmium-reducing foliar barrier of other formulas, the cadmium-reducing foliar barrier of the invention significantly reduces the cadmium content in rice brown rice, is simple to operate, and raw materials are easy to obtain, and waste is turned into treasure. Several barrier components cooperate with each other to jointly play the role of reducing cadmium in rice, and have a strong prospect for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. The drawings in the following description are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0028] Figure 1 This is a diagram of the preparation process of the cadmium-reducing leaf surface control agent provided by an embodiment of the present invention;

[0029] Figure 2 This is a diagram of the application process of the cadmium-reducing foliar inhibitor provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0032] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations and / or combinations thereof.

[0033] Embodiment 1:

[0034] Comparison of the dissolution state of cadmium-reducing foliar inhibitors with and without husk wood vinegar:

[0035] 1. Dissolve 200g sodium silicate and 150g zinc sulfate in 650g rice husk wood vinegar:

[0036] With husk wood vinegar as the component, sodium silicate 20% and zinc sulfate 15% were added. Due to the color of husk wood vinegar itself (dark brown), no precipitation was observed in the solution system and on the surface. Microwave oscillation for 24 hours, after standing for 24 hours, no precipitation reaction was observed. After filtration, the surface of the filter paper was dark brown, and after weighing, the filter paper weight increased by 9.86g.

[0037] 2. Replace the husk wood vinegar with distilled water, that is, dissolve 200g of sodium silicate and 150g of zinc sulfate in 650g of distilled water:

[0038] When distilled water is used as a component, precipitation is easily generated after the system is mixed. After microwave vibration for 24 hours, most of the precipitation has not been eliminated after standing for 24 hours. This is because sodium silicate and zinc sulfate react in distilled water to form zinc silicate precipitation.

[0039] After filtering the microwave-oscillated system, the surface of the filter paper appeared green-yellow-brown, and the weight of the filter paper increased by 109.48 g.

[0040] The rice husk wood vinegar of the invention can make sodium silicate, zinc sulfate and chlorinated ...

[0041] Embodiment 2:

[0042] like Figure 1 As shown, 200 g of sodium silicate and 150 g of zinc sulfate are dissolved in 650 g of rice husk wood vinegar to obtain the cadmium-reducing foliar control agent, hereinafter referred to as this material.

[0043] Spraying period effect verification test: Field plot tests of late rice were carried out at three different periods: tillering period, heading period, and booting period. The test process is as follows:

[0044] like Figure 2 As shown, use a measuring cylinder to take 200 mL of the cadmium-reducing foliar inhibitor, add clean water (i.e. 100 L of water) at a ratio of 1:500, and spray it on the rice with a back sprayer at a dosage of 3 L of the cadmium-reducing foliar inhibitor stock solution per hectare according to the planned time. The control is sprayed with an equal amount of clean water.

[0045] Test location: Penghu Village, Zhushan Town, Yushui District, Xinyu City

[0046] Trial time: 2023 late rice season

[0047] Experimental setup: 1 plot per treatment, 4 replicates per treatment. The plot area is 15 square meters (i.e. 4.5 mL of cadmium-reducing foliar inhibitor stock solution per plot, i.e. 2250 mL of water diluted cadmium-reducing foliar inhibitor and sprayed, and the control group is the same amount of clean water), 25 cm space is left between plots, and no ridges are set. All plots are in the same field.

[0048] Experimental fields: total cadmium content in the soil was 0.57 mg / kg, pH was 5.43, effective cadmium content was 0.27 mg / kg, and the rice varieties were uniform and were the main cultivated varieties locally.

[0049] Experimental treatment 1: When the rice is in the tillering stage, take 4.5 mL of this material, dilute it with 500 times of water, and spray it on the rice leaves using a manual backpack sprayer in mid-August; the control is directly sprayed with an equal amount of clean water.

[0050] Experimental treatment 2: When rice is at heading stage, take 4.5 mL of this material, dilute it with 500 times of water, and spray it on rice leaves using a manual backpack sprayer in early September; the control is directly sprayed with an equal amount of clean water.

[0051] Experimental treatment three: When rice is in the booting stage, take 4.5 mL of this material, dilute it with 500 times of water, and spray it on the rice leaves using a manual backpack sprayer in mid-September; the control is directly sprayed with an equal amount of clean water.

[0052] Experimental treatment 4: During the tillering stage and booting stage of rice, take 4.5 mL of this material, dilute it with 500 times of water, and spray it on the rice leaves using a manual backpack sprayer; the control is to directly spray an equal amount of clean water at the same time.

[0053] Sample collection: During the rice maturity period (early November), rice grains were collected and threshed.

[0054] Test results: Compared with spraying an equal amount of clean water, spraying the cadmium-reducing foliar barrier agent of the present invention significantly reduced the cadmium content in brown rice, among which spraying 4.5 mL each at the tillering stage and the booting stage had the most significant effect. Compared with spraying an equal amount of clean water at the same stage, the cadmium reduction effect was 72.97%.

[0055] Spraying period Cadmium content in brown rice 4.5mL during tillering stage, diluted with water 500 times 0.27±0.03 Spray an equal amount of water 0.36±0.05 4.5mL at heading stage, diluted with water 500 times 0.28±0.03 Spray an equal amount of water 0.37±0.04 4.5mL at booting stage, diluted with water 500 times 0.24±0.04 Spray an equal amount of water 0.37±0.04 4.5mL each at tillering and booting stages, diluted with water 500 times 0.10±0.03 Apply equal amount of water at tillering and booting stages 0.37±0.05

[0056] Compared with Example 2:

[0057] Comparative Example 1:

[0058] 350 g of zinc sulfate was dissolved in 650 g of rice husk wood vinegar to obtain the cadmium-reducing foliar control agent in Comparative Example 1.

[0059] Comparative Example 2:

[0060] 350 g of sodium silicate was dissolved in 650 g of rice husk wood vinegar to obtain the cadmium-reducing foliar control agent in Comparative Example 2.

[0061] Comparative Example 3:

[0062] 200 g of sodium silicate and 150 g of zinc sulfate were dissolved in 650 g of acetic acid to obtain the cadmium-reducing foliar control agent in Comparative Example 3.

[0063] Comparative Example 4:

[0064] Since sodium silicate and zinc sulfate cannot coexist in water, 525g of sodium silicate was taken to obtain the cadmium-reducing foliar barrier agent a in Comparative Example 4; 475g of zinc sulfate was taken to obtain the cadmium-reducing foliar barrier agent b in Comparative Example 4; 4.5mL of cadmium-reducing foliar barrier agent a was taken with a measuring cylinder during the tillering period, and clean water (i.e., 2250mL of water) was added at a ratio of 1:500, and the mixture was sprayed on the rice with a back sprayer. After an interval of 2 days, 4.5mL of cadmium-reducing foliar barrier agent b was taken with a measuring cylinder, and the mixture was added at a ratio of 1:500, and the mixture was sprayed on the rice with a back sprayer. Add clean water (i.e. 2250mL water) at a ratio of 1:500 and spray it on the rice with a back sprayer. At the booting stage, use a measuring cylinder to take 4.5mL of cadmium-reducing foliar inhibitor a, add clean water (i.e. 2250mL water) at a ratio of 1:500, and spray it on the rice with a back sprayer. After an interval of 2 days, use a measuring cylinder to take 4.5mL of cadmium-reducing foliar inhibitor b, add clean water (i.e. 2250mL water) at a ratio of 1:500, and spray it on the rice with a back sprayer.

[0065] Comparative Example 5:

[0066] 1000g of rice husk wood vinegar was used to obtain the cadmium-reducing foliar control agent in Comparative Example 5.

[0067] Comparative Example 6:

[0068] Take 1000 g of sodium silicate to obtain the cadmium-reducing foliar inhibitor in Comparative Example 6.

[0069] Comparative Example 7:

[0070] Take 1000 g of zinc sulfate to obtain the cadmium-reducing foliar control agent in Comparative Example 7.

[0071] Effect verification test during spraying period: The foliar control agents in comparative examples 1-7 were tested in late rice field plots at the tillering stage and the booting stage. The test process is as follows:

[0072] During the tillering stage, use a measuring cylinder to take 4.5 mL of each cadmium-reducing foliar inhibitor, add clean water (i.e. 2250 mL of water) at a ratio of 1:500, and spray it on the rice with a back sprayer. During the booting stage, use a measuring cylinder to take 4.5 mL of each cadmium-reducing foliar inhibitor, add clean water (i.e. 2250 mL of water) at a ratio of 1:500, and spray it on the rice with a back sprayer.

[0073] Test location: Penghu Village, Zhushan Town, Yushui District, Xinyu City

[0074] Trial time: 2023 late rice season

[0075] Experimental setup: The above comparative examples 1-7 were treated in one plot, and each treatment was repeated 4 times. The plot area was 15 square meters (i.e., 4.5 mL of each cadmium-reducing foliar barrier agent stock solution was applied to each plot, i.e., 2250 mL of water was used to dilute the cadmium-reducing foliar barrier agent and then sprayed, and the control group was sprayed with the same amount of clean water), 25 cm of space was left between the plots, and no ridges were set. All plots were in the same field.

[0076] Experimental fields: total cadmium content in the soil was 0.57 mg / kg, pH was 5.43, effective cadmium content was 0.27 mg / kg, and the rice varieties were uniform and were the main cultivated varieties locally.

[0077] Spraying period: Use the foliar control agent in Example 2 and Comparative Examples 1 to 7, and spray once at the tillering stage and booting stage of late rice.

[0078] Sample collection: During the rice maturity period (early November), rice grains were collected and threshed.

[0079] The test results show the difference between Comparative Examples 1 to 7 and the embodiment.

[0080] Group Spraying period Cadmium content in brown rice (mg / kg) Equivalent clean water reference group Apply equal amount of water during tillering and heading 0.36±0.05 Example 2 4.5mL each for tillering and heading, diluted with water 500 times 0.10±0.03 Comparative Example 1 4.5mL each for tillering and heading, diluted with water 500 times 0.28±0.02 Comparative Example 2 4.5mL each for tillering and heading, diluted with water 500 times 0.25±0.03 Comparative Example 3 4.5mL each for tillering and heading, diluted with water 500 times 0.23±0.02 Comparative Example 4 4.5mL each for tillering and heading, diluted with water 500 times 0.20±0.04 Comparative Example 5 4.5mL each for tillering and heading, diluted with water 500 times 0.32±0.06 Comparative Example 6 4.5mL each for tillering and heading, diluted with water 500 times 0.35±0.03 Comparative Example 7 4.5mL each for tillering and heading, diluted with water 500 times 0.30±0.03

[0081] According to the experimental results of the above embodiments, the sodium silicate, zinc sulfate and husk wood vinegar components of the present invention can cooperate with each other, and through their joint action, the cadmium content in rice brown rice can be significantly reduced, and a foliar barrier agent for reducing cadmium in rice and an application method thereof are provided. Compared with other barrier agent formulations, the foliar barrier agent of the present invention only needs to be sprayed once at the tillering stage and the booting stage, and has an extremely outstanding cadmium reduction effect, thus solving the technical problem that rice cannot use foliar barrier agents to quickly reduce cadmium in the prior art.

[0082] In summary, the invention discloses a rice cadmium-reducing foliar barrier and an application method thereof. The cadmium-reducing foliar barrier is prepared by compounding rice husk wood vinegar, sodium silicate and zinc sulfate, wherein the mass ratio is 15%-20% of sodium silicate, 10%-15% of zinc sulfate and the remainder is rice husk wood vinegar. The cadmium-reducing foliar barrier is sprayed at the tillering stage and the booting stage of rice respectively. Compared with spraying an equal amount of clean water and a rice cadmium-reducing foliar barrier of other formulas, the cadmium-reducing foliar barrier of the invention significantly reduces the cadmium content in rice brown rice, is simple to operate, and raw materials are easily obtained, and waste is turned into treasure. Several barrier components cooperate with each other to jointly play the role of reducing cadmium in rice, and have a strong prospect for promotion and application.

[0083] At this point, those skilled in the art recognize that, although the embodiments of the present invention have been shown and described in detail herein, many other variations or modifications that conform to the principles of the present invention can still be directly determined or derived based on the contents disclosed in the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and recognized as covering all such other variations or modifications.

Claims

1. A rice cadmium reduction foliar control agent, characterized in that: The foliar barrier agent is composed of the following components: Husk wood vinegar, sodium silicate, zinc sulfate; The mass ratio of the rice husk wood vinegar, sodium silicate and zinc sulfate is: Sodium silicate 15%-20%, zinc sulfate 10%-15%, the balance is rice husk wood vinegar; The preparation method of the rice husk wood vinegar is: In the drying stage, the temperature is 20-60°C, during which the rice is completely dried; In the hulling stage, the husk is separated from the brown rice by a rice mill; In the fermentation stage, the husks are piled up for fermentation, and the fermentation temperature is controlled at 70-150°C. During this process, the husks begin to decompose, and the gaseous wood vinegar components produced in this process are cooled and recovered by a condenser to form a wood vinegar stock solution; Separation and refining: The wood vinegar stock solution is collected and stored in a sedimentation tank, and is separated and refined by standing for more than 3 months to obtain the entire wood vinegar stock solution.

2. The method for applying the rice cadmium reduction foliar control agent as claimed in claim 1, characterized in that: The application method comprises the following steps: The sodium silicate and zinc sulfate in the rice cadmium-reducing foliar control agent are dissolved in proportion in the rice husk wood vinegar solution, and the mixture is evenly mixed to obtain the foliar control agent, which is then diluted with a diluent and sprayed evenly on the rice leaves during the rice growth process.

3. The method for applying the rice cadmium reduction foliar control agent as claimed in claim 2, characterized in that: The diluent of the foliar barrier agent is water.

4. The method for applying the rice cadmium reduction foliar control agent as claimed in claim 2, characterized in that: The dilution multiple of the foliar barrier agent is 500-800 times.

5. The method for applying the rice cadmium reduction foliar control agent as claimed in claim 2, characterized in that: The rice growth process is the tillering stage and / or the booting stage.

6. The method for applying the rice cadmium reduction foliar control agent as claimed in claim 2, characterized in that: The dosage of the foliar control agent before dilution is 3-4 L / hectare.

7. The method for applying the cadmium-reducing foliar control agent for rice as claimed in claim 2, characterized in that: The foliar barrier agent is sprayed on the rice leaves before 10 am and after 4 pm on a sunny or cloudy day, with a suitable temperature range of 15-30°C.

8. The method for applying the cadmium-reducing foliar control agent for rice as claimed in claim 2, characterized in that: The foliar barrier agent is sprayed 1 to 3 times during the tillering stage and the booting stage.

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