Application of daidzein in reducing cadmium content in soil

Abstract

The present invention provides the application of daidzein in reducing the cadmium content in soil. Daidzein is a secondary metabolite of leguminous plants, and its function for the plant itself is to help the plant cope with biotic and abiotic stresses, such as pests, diseases and environmental pressures, and has characteristics such as antioxidant and disease resistance, and can regulate plant growth, which helps to improve the yield and quality of crops. The present invention further discovers that daidzein can also reduce the content of available cadmium in soil, which enables daidzein to play multiple functions when applied to the field.

Description

Technical Field

[0001] The present invention relates to the field of agricultural planting, and particularly to the application of daidzein in reducing the cadmium content in soil. Background Art

[0002] Cadmium (Cd) pollution is a globally recognized environmental problem and has attracted much attention from countries around the world. In agricultural production, rice is often more likely to accumulate Cd than other crops, and the issue of rice safety has drawn significant attention. Controlling Cd pollution in paddy soil has become the top priority for food security, and the Cd pollution problem urgently needs to be solved. Therefore, screening materials that can reduce the cadmium content, especially the available cadmium content, in paddy soil is of great significance. Summary of the Invention

[0003] One aspect of the present invention provides the application of daidzein in reducing the cadmium content in soil.

[0004] In a specific embodiment, the daidzein is used to reduce the available cadmium content in soil.

[0005] In a specific embodiment, the daidzein is used to reduce the available cadmium content in paddy fields.

[0006] In a specific embodiment, the paddy field is a rice paddy field.

[0007] In a specific embodiment, the dosage of the daidzein is 0.1 g / kg to 3 g / kg of soil, and the converted field dosage is 225 kg / ha to 6750 kg / ha. Among them, the field application amount is calculated based on the mass of the plow layer soil of 1 hectare of land being 2,250,000 kg.

[0008] Advantages of the present invention: Daidzein is a secondary metabolite of leguminous plants. Its function for the plant itself is to help the plant cope with biotic and abiotic stresses, such as pests, diseases, and environmental pressures, and has characteristics such as antioxidant and disease resistance, and can regulate plant growth, which helps to improve crop yield and quality. The present invention further discovers that daidzein can also reduce the content of available cadmium in soil, especially in paddy fields, which enables daidzein to play multiple functions when applied in the field. Brief Description of the Drawings

[0009] Figure 1 Shows the effect of daidzein on soil pH.

[0010] Figure 2 Shows the effect of daidzein on the available cadmium content in soil. Detailed Embodiments

[0011] The present invention will be further described below in conjunction with embodiments, but the embodiments of the present invention are only exemplary descriptions, and in no case do they constitute a limitation to the present invention.

[0012] Unless otherwise specified, the reagents in the embodiments of the present invention can be purchased through commercial channels.

[0013] Daidzein, with a content of 98 wt%, was purchased from Shanghai Yuanye Bio-Technology Co., Ltd.

[0014] The plough layer soil of paddy fields in Nijiangkou Town, Yiyang City, Hunan Province was selected, air-dried until the water content was lower than 5 wt%, and passed through a 2 mm sieve to obtain dry and fresh soil.

[0015] Blank control treatment (CK): Weigh 100 g of dry and fresh soil into a 250 mL culture bottle. After filling the bottle, add 100 mL of distilled water according to the ratio of water mass: soil mass = 1:1. Seal the culture bottle with a breathable and water-impermeable sealing film, and culture it in the dark at 25 ± 2 °C. Make up water by the weighing method every 7 days. Each culture bottle is used as one replicate, with a total of 3 replicates.

[0016] Treatment with 0.01% daidzein (0.01%D): Add daidzein at 0.1 g / kg (daidzein / dry and fresh soil) to the dry and fresh soil to obtain daidzein soil. Weigh 100 g of daidzein soil into a 250 mL culture bottle. After filling the bottle, add 100 mL of distilled water according to the ratio of water mass: soil mass = 1:1. Seal the culture bottle with a breathable and water-impermeable sealing film, and culture it in the dark at 25 ± 2 °C. Make up water by the weighing method every 7 days. Each culture bottle is used as one replicate, with a total of 3 replicates.

[0017] Treatment with 0.05% daidzein (0.05%D): The amount of daidzein added is 0.5 g / kg (daidzein / dry and fresh soil), and the others are the same as 0.01%D.

[0018] Treatment with 0.1% daidzein (0.1%D): The amount of daidzein added is 1 g / kg (daidzein / dry and fresh soil), and the others are the same as 0.01%D.

[0019] Treatment with 0.3% daidzein (0.3%D): The amount of daidzein added is 3 g / kg (daidzein / dry and fresh soil), and the others are the same as 0.01%D.

[0020] Treatment with 0.5% daidzein (0.5%D): The amount of daidzein added is 5 g / kg (daidzein / dry and fresh soil), and the others are the same as 0.01%D.

[0021] Treatment with 0.7% daidzein (0.7%D): The amount of daidzein added is 7 g / kg (daidzein / dry and fresh soil), and the others are the same as 0.01%D.

[0022] Treatment with 1% daidzein (1%D): The amount of daidzein added was 10 g / kg (daidzein / dry and fresh soil), and the others were the same as 0.01%D.

[0023] Example 1: Effect of daidzein on soil pH value.

[0024] Taking the preparation day as day 0, each treatment was placed in a biochemical incubator at 25 ± 2 °C for dark incubation for 90 days, and the pH value of the soil was measured on the 90th day of incubation. The results are shown in Figure 1 .

[0025] According to Figure 1 the results, daidzein at low dosages (0.01% to 0.05%) will slightly increase the soil pH value. As the dosage of daidzein gradually increases, that is, when the dosage is 0.1% to 0.5%, the soil pH value gradually increases, first rising from 6.63 to 7.06 (when the daidzein dosage is 0.3%), and then the soil pH value tends to be stable, maintaining at 7.45 to 7.50.

[0026] The suitable pH range for rice growth is relatively wide. However, the more suitable soil pH value is usually between 5.5 and 7.5. Within this pH value range, the nutrients in the soil are more easily absorbed by rice, and the growth of rice is good. For dryland crops such as corn and wheat, the suitable pH is neutral to slightly alkaline. Therefore, this pH value range will not affect the growth of corn and wheat. In summary, although the addition of daidzein has a certain impact on soil pH, it will not affect the growth of conventional crops.

[0027] Example 2: Effect of daidzein on soil available cadmium content.

[0028] Taking the preparation day as day 0, each treatment was placed in a biochemical incubator at 25 ± 2 °C for dark incubation for 90 days. Soil samples of each treatment were collected on the 90th day of incubation, and each soil sample was air-dried.

[0029] Weigh 5.00 grams of the above air-dried soil sample, extract it with 25 ml of 0.1 mol / L calcium chloride aqueous solution for 2 hours, centrifuge at 8000 rmp and filter to obtain the filtrate. The cadmium concentration in the filtrate was measured by inductively coupled plasma mass spectrometry (ICP-MS, Optima 8300, PerkinElmer, USA), and the soil available cadmium content was calculated using formula 1. The results are shown in Figure 2 .

[0030] Formula 1: Available cadmium content in air-dried soil sample (mg / kg) = concentration of the filtrate to be measured (μg / L) × V (ml) × 0.001 / M.

[0031] Note: V: the original volume of 0.1 mol / L calcium chloride aqueous solution added to the air-dried soil sample, which is 25 mL in the above operation; M: the weighed amount of the air-dried soil sample, which is 5.00 g in the above operation; 0.001: unit conversion.

[0032] According to Figure 2 The results show that compared with the CK treatment, daidzein can significantly reduce the content of available cadmium in the soil. Among them, at low dosages of 0.01% and 0.05%, the contents of available cadmium in the soil are reduced by 19.6% and 28.1% respectively; at a daidzein dosage of 0.1%, the content of available cadmium in the soil is reduced by 51.6%; at a daidzein dosage of 0.3%, the content of available cadmium in the soil is reduced by 71.7%; afterwards, with the further increase of the daidzein dosage, the reduction rate of the available cadmium content in the soil gradually tends to be stable, and the reduction rate is 73.1% to 77.0% (0.5%D, 0.7%D and 1%D). Considering cost savings, the dosage of daidzein can be controlled below 0.3%. At this time, the impact of daidzein on the soil pH is also smaller.

[0033] Although the present invention has been described with reference to specific embodiments, those skilled in the art should understand that various changes can be made without departing from the true spirit and scope of the present invention. In addition, various changes can be made to the subject matter, spirit and scope of the present invention to adapt to specific situations, materials, material compositions and methods. All such changes are included within the scope of the claims of the present invention.

Claims

1. Application of daidzein in reducing cadmium content in soil.

2. The use according to claim 1, characterized in that: The daidzein is used for reducing the effective cadmium content in soil.

3. The use according to claim 1, characterized in that: The daidzein is used for reducing the effective cadmium content in paddy fields.

4. The use according to claim 3, characterized in that: The paddy field is a rice field.

5. The use according to claim 1, characterized in that: The dosage of daidzein is 225 kg / hectare to 6750 kg / hectare.

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