WO2022246880A1 - 一种降低稻米镉含量的轻简化方法及应用 - Google Patents

一种降低稻米镉含量的轻简化方法及应用 Download PDF

Info

Publication number
WO2022246880A1
WO2022246880A1 PCT/CN2021/097651 CN2021097651W WO2022246880A1 WO 2022246880 A1 WO2022246880 A1 WO 2022246880A1 CN 2021097651 W CN2021097651 W CN 2021097651W WO 2022246880 A1 WO2022246880 A1 WO 2022246880A1
Authority
WO
WIPO (PCT)
Prior art keywords
selenium
seed soaking
rice
concentration
soaking agent
Prior art date
Application number
PCT/CN2021/097651
Other languages
English (en)
French (fr)
Inventor
周静
夏睿智
梁家妮
刘梦丽
周俊
Original Assignee
中国科学院南京土壤研究所
江西洁地环境治理生态科技有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 中国科学院南京土壤研究所, 江西洁地环境治理生态科技有限公司 filed Critical 中国科学院南京土壤研究所
Priority to US17/617,334 priority Critical patent/US20240074439A1/en
Priority to GB2204002.6A priority patent/GB2610456A/en
Publication of WO2022246880A1 publication Critical patent/WO2022246880A1/zh

Links

Images

Classifications

    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
    • A01G22/00—Cultivation of specific crops or plants not otherwise provided for
    • A01G22/20—Cereals
    • A01G22/22—Rice
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01B—SOIL WORKING IN AGRICULTURE OR FORESTRY; PARTS, DETAILS, OR ACCESSORIES OF AGRICULTURAL MACHINES OR IMPLEMENTS, IN GENERAL
    • A01B79/00—Methods for working soil
    • A01B79/02—Methods for working soil combined with other agricultural processing, e.g. fertilising, planting
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01C—PLANTING; SOWING; FERTILISING
    • A01C1/00—Apparatus, or methods of use thereof, for testing or treating seed, roots, or the like, prior to sowing or planting
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01C—PLANTING; SOWING; FERTILISING
    • A01C1/00—Apparatus, or methods of use thereof, for testing or treating seed, roots, or the like, prior to sowing or planting
    • A01C1/08—Immunising seed

Definitions

  • the invention relates to the field of heavy metal pollution prevention and control, in particular to a light and simplified method and application for reducing cadmium content in rice.
  • Cd is a non-essential element for organisms, and it is considered as the most toxic heavy metal due to its high mobility, high toxicity, high accumulation and difficult elimination. After heavy metal Cd enters the soil, due to its high biological activity, it is easily absorbed and enriched by plants. At the same time, with the expansion of the food chain, it poses a threat to human health, including osteoporosis, arteriosclerosis, and kidney damage.
  • Rice is one of the main food products in my country. Soil Cd pollution will cause the Cd content in rice to exceed the standard, which will cause harm to human health. It can be seen that it is particularly important to control the Cd content in rice. There are many measures to prevent and control rice Cd exceeding the standard. For the contaminated soil, the main method is to restore it to achieve the purpose of safe production. A more effective method for remediation and control of Cd pollution in farmland is to apply soil passivation materials, including lime, fly ash, hydroxyapatite, organic fertilizers, etc., to increase soil pH, increase soil adsorption sites, and reduce soil Cd activity, inhibiting root uptake in rice.
  • soil passivation materials including lime, fly ash, hydroxyapatite, organic fertilizers, etc.
  • the present invention provides a light and simplified method and application for reducing cadmium content in rice.
  • the method of the present invention can obtain rice with Cd content not exceeding the standard with relatively low cost and convenient operation.
  • the present invention provides the following technical solutions:
  • the invention provides a seed soaking agent for reducing cadmium content in rice, the active ingredients of the seed soaking agent include trace elements required by plants, and the trace elements include one of selenium, silicon, zinc and iron, Or a mixture of iron, silicon and zinc with selenium;
  • the concentration of selenium in the seed soaking agent is 0.5-6 mg/L;
  • the concentration of silicon in the seed soaking agent is 1.5-5 mmol/L;
  • the concentration of zinc in the seed soaking agent is 0.25-0.75mol/L;
  • the concentration of iron in the seed soaking agent is 3-5 mg/L;
  • the concentration of selenium in the seed soaking agent is 4-6 mg/L, and the concentration of iron is 3-5 mg/L;
  • the concentration of selenium in the seed soaking agent is 4-6 mg/L, and the concentration of silicon is 1.5-5 mmol/L;
  • the concentration of selenium in the seed soaking agent is 4-6 mg/L, and the concentration of zinc is 0.25-0.75 mol/L.
  • the source of the selenium includes Na 2 SeO 3 ;
  • the source of silicon includes silicic acid
  • the source of zinc element includes ZnSO 4 ⁇ 7H 2 O;
  • the source of the iron includes FeSO 4 ⁇ 7H 2 O.
  • the invention provides a light and simplified method for reducing the Cd content of rice, comprising: mixing seeds and a seed soaking agent to soak the seeds, sowing the soaked seeds, and obtaining rice with low Cd content after harvesting;
  • the active ingredients of the seed soaking agent include trace elements; said trace elements include selenium, silicon, zinc or iron, or a mixture of selenium and iron, a mixture of selenium and silicon, or a mixture of selenium and zinc;
  • the concentration of selenium in the seed soaking agent is 0.5-6 mg/L;
  • the concentration of silicon in the seed soaking agent is 1.5-5 mmol/L;
  • the concentration of zinc in the seed soaking agent is 0.25-0.75mol/L;
  • the concentration of iron in the seed soaking agent is 3-5 mg/L;
  • the concentration of selenium in the seed soaking agent is 4-6 mg/L, and the concentration of iron is 3-5 mg/L;
  • the concentration of selenium in the seed soaking agent is 4-6 mg/L, and the concentration of silicon is 1.5-5 mmol/L;
  • the concentration of selenium in the seed soaking agent is 4-6 mg/L, and the concentration of zinc is 0.25-0.75 mol/L.
  • the mass volume ratio of the seeds to the seed soaking agent is 1 g:(4-7) mL; the water content of the seeds is 12%-14%.
  • the source of the selenium includes Na 2 SeO 3 ;
  • the source of silicon includes silicic acid
  • the source of zinc element includes ZnSO 4 ⁇ 7H 2 O;
  • the source of the iron includes FeSO 4 ⁇ 7H 2 O.
  • the preparation method of the seed soaking agent comprises: mixing silicic acid with water and ultrasonically treating it to obtain the seed soaking agent;
  • the preparation method of the seed soaking agent comprises: mixing silicic acid with water and ultrasonically treating it to obtain a silicic acid suspension;
  • the temperature of the ultrasonic treatment is 30° C.; the time of the ultrasonic treatment is 7-8 hours.
  • the mixing of the seeds and the seed soaking agent also includes standing treatment; the standing is carried out in the dark, the standing time is 24-26 hours, and the temperature is 24-29°C.
  • the germination treatment of soaked seeds is also included; the time of the germination treatment is 3-5 days.
  • the seed is also sterilized; the sterilized method includes:
  • the seeds are sterilized with an aqueous ethanol solution, they are then sterilized with an aqueous solution of sodium hypochlorite, and finally rinsed with sterile water; the volume concentration of ethanol in the aqueous solution of ethanol is 65% to 75%; the content of available chlorine in the aqueous solution of sodium hypochlorite is 5% to 7%. %.
  • the disinfection time of the ethanol aqueous solution is 4-6 minutes; the disinfection time of the sodium hypochlorite aqueous solution is 25-35 minutes.
  • the present invention also provides the application of the above method in reducing the Cd content of rice planted on Cd polluted soil.
  • the present invention provides a light and simplified method for reducing cadmium content in rice, comprising: mixing and soaking seeds with a seed soaking agent, sowing the soaked seeds, and obtaining rice with low Cd content after harvesting; the seed soaking agent
  • the active ingredients include trace elements needed by plants; the trace elements include selenium, silicon, zinc or iron, or a mixture of selenium and iron, a mixture of selenium and silicon, or a mixture of selenium and zinc mixture; when the trace element is selenium, the concentration of selenium in the seed soaking agent is 0.5 to 6 mg/L; when the trace element is silicon, the concentration of silicon in the seed soaking agent is 1.5 to 6 mg/L; 5mmol/L; when the trace element is zinc, the concentration of zinc in the seed soaking agent is 0.25 ⁇ 0.75mol/L; when the trace element is iron, the concentration of iron in the seed soaking agent is 3-5 mg/L; when the trace element is a mixture of selenium and iron, the
  • Fig. 1 is the analysis result figure of different treatment grain Cd content in the application example 1;
  • Fig. 2 is the analysis result figure of Cd content in rice root of different treatments in application example 1;
  • Fig. 3 is the graph of analysis results of Cd content in rice stems of different treatments in Application Example 1;
  • Fig. 4 is the analysis result figure of Cd content in rice leaves of different treatments in Application Example 1;
  • Fig. 5 is the figure of analysis results of Cd content in grains of different treatments in application example 2;
  • Fig. 6 is the analysis result figure of Cd content in rice root of different treatments in application example 2;
  • Fig. 7 is the graph of analysis results of Cd content in rice stems of different treatments in Application Example 2;
  • Fig. 8 is the analysis result figure of Cd content in rice leaves of different treatments in Application Example 2;
  • Fig. 9 is the analysis result figure of Cd content in grains of different treatments in application example 3.
  • Fig. 10 is the analysis result figure of Cd content in rice root of different treatments in application example 3.
  • Fig. 11 is the graph of the analysis results of Cd content in rice stems of different treatments in Application Example 3;
  • Fig. 12 is the analysis result figure of Cd content in rice leaves of different treatments in Application Example 3;
  • Fig. 13 is the figure of analysis results of Cd content in grains of different treatments in application example 4.
  • Fig. 14 is the analysis result figure of Cd content in rice root of different treatments in application example 4.
  • Fig. 15 is a graph showing the analysis results of Cd content in rice stems of different treatments in Application Example 4;
  • Fig. 16 is the analysis result figure of Cd content in rice leaves of different treatments in Application Example 4.
  • Fig. 17 is a graph showing the results of determination of Cd content in the seeds of Chuangliangyou 276 variety in application example 5 after soaking seeds with different Se concentrations;
  • Fig. 18 is a graph showing the results of determination of Cd content in the grains of Wuyouzhanhua variety in application example 5 after soaking seeds with different Se concentrations;
  • Fig. 19 is the content measurement result figure of Se in the seed after different Se concentration soaking treatment in application example 6;
  • Fig. 20 is a graph showing the measurement results of Cd content in the seeds of different varieties in Application Example 7 after soaking with different Se concentrations.
  • the invention provides a light and simplified method for reducing the cadmium content of rice, comprising: mixing seeds and a seed soaking agent to soak the seeds, sowing the soaked seeds, and obtaining rice with low Cd content after harvesting;
  • the active ingredients of the seed soaking agent include trace elements; said trace elements include selenium, silicon, zinc or iron, or a mixture of selenium and iron, a mixture of selenium and silicon or a mixture of selenium and zinc; when said trace
  • the concentration of selenium in the seed soaking agent is 0.5 to 6 mg/L; when the trace element is silicon, the concentration of silicon in the seed soaking agent is 1.5 to 5 mmol/L;
  • the trace element is zinc, the concentration of zinc in the seed soaking agent is 0.25 to 0.75 mol/L; when the trace element is iron, the concentration of iron in the seed soaking agent is 3 to 5 mg/L;
  • the trace element is a mixture of selenium and iron, the concentration of selenium in the seed soaking agent
  • the present invention does not limit the source of each component in the seed soaking agent, and commercially available products well known to those skilled in the art can be used.
  • the invention mixes the seeds and the seed soaking agent to soak the seeds to obtain the soaked seeds.
  • the seeds are preferably sterilized; the method of disinfection preferably includes: after the seeds are sterilized with an aqueous solution of ethanol, then sterilized with an aqueous solution of sodium hypochlorite, and finally rinsed with sterile water;
  • the volume concentration of ethanol in the ethanol aqueous solution is preferably 65% ⁇ 75%, more preferably 70%;
  • the time of ethanol aqueous solution disinfection is preferably 4 ⁇ 6min, more preferably 5min;
  • Available chlorine content is preferably 5% in the described sodium hypochlorite aqueous solution ⁇ 7%, more preferably 6%; the disinfection time of sodium hypochlorite aqueous solution is preferably 25 ⁇ 35min, more preferably 30min; the number of times of rinsing is preferably 5 ⁇ 6 times.
  • the concentration of selenium in the seed soaking agent is 0.5-6 mg/L, preferably 1-5.5 mg/L, more preferably 5 mg/L;
  • the source of elements preferably includes Na 2 SeO 3 ; the purity of the Na 2 SeO 3 is preferably greater than 99%;
  • the preparation method of the seed soaking agent preferably includes: mixing Na 2 SeO 3 with water to obtain the seed soaking agent; the present invention mixes
  • the method of mixing is not limited, and a mixing method well known to those skilled in the art can be used.
  • the present invention can improve the antioxidant enzymes (superoxide dismutase SOD, catalase CAT and glutathione peroxidation) of the grown rice roots and leaves by soaking the rice seeds with an appropriate concentration of selenium element solution.
  • GSH-Px) activity and proline (Pro) content and reduce hydrogen peroxide (H 2 O 2 ) and malondialdehyde (MDA) content, and facilitate the formation of insoluble Cd-selenium complexes in rice roots , thereby reducing the content of biologically available Cd in the soil solution, inhibiting the absorption and transportation of Cd by rice; in addition, it can also increase the reactive oxygen species ROS of rice cells, reduce the mitochondrial membrane potential, and increase the lignin content of rice plants and cell wall thickness; in addition, selenium soaking treatment can also reduce the expression of Cd uptake-related genes (OsNramp5) and transport-related genes (OsLCT1) in rice, and activate the expression of lignin synthesis-related genes (Os
  • the concentration of silicon in the seed soaking agent is 1.5-5mmol/L, preferably 1.8-4mmol/L, more preferably 2mmol/L;
  • the source of the silicic acid preferably includes silicic acid; the purity of the silicic acid is preferably greater than 99%;
  • the preparation method of the seed soaking agent preferably includes: mixing silicic acid with water and ultrasonic treatment to obtain the seed soaking agent; the temperature of the ultrasonic treatment is preferably 30 °C; the ultrasonic treatment time is preferably 7-8 hours, more preferably 7.5 hours; the ultrasonic treatment equipment preferably includes an ultrasonic cleaner.
  • the source of the ultrasonic cleaner is not limited, and commercially available products well known to those skilled in the art can be used.
  • the invention can uniformly disperse the silicic acid in water through ultrasonic treatment.
  • the absorption and transport of Cd by the grown rice can be reduced by down-regulating the Cd transport gene, and the oxidative stress induced by Cd can be improved by enhancing the activity of antioxidant enzymes.
  • the concentration of zinc in the seed soaking agent is 0.25 to 0.75 mol/L, preferably 0.5 mol/L;
  • the source of zinc preferably includes ZnSO 4 . 7H 2 O;
  • the purity of the ZnSO 4 7H 2 O is preferably greater than 99%;
  • the preparation method of the seed soaking agent preferably includes: mixing ZnSO 4 7H 2 O with water to obtain the seed soaking agent; the present invention mixes It is not limited, and a mixing method well known to those skilled in the art can be used.
  • the present invention soaks the rice seeds with an appropriate concentration of zinc element solution, reduces the ability of the seeds and rice plants to absorb and transport Cd through the antagonism of zinc to Cd, and can increase the chlorophyll a, b, and chlorophyll in the grown rice leaves at the same time.
  • a+b content and enhance the activity of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), reduce the content of malondialdehyde (MDA), increase the content of soluble protein and soluble sugar content, thereby increasing the activity of antioxidant enzymes during the growth of rice, slowing down lipid peroxidation, enhancing the level of substance metabolism, and reducing the Cd content of rice.
  • the concentration of iron in the seed soaking agent is 3-5 mg/L, preferably 4 mg/L;
  • the source of iron preferably includes FeSO 4 ⁇ 7H 2 O
  • the purity of the FeSO 4 7H 2 O is preferably greater than 98%;
  • the preparation method of the seed soaking agent preferably includes: mixing FeSO 4 7H 2 O with water to obtain the seed soaking agent; the present invention does not limit the mixing method, A mixing method known to those skilled in the art can be used.
  • the invention soaks the rice seeds with an iron element solution of a suitable concentration, not only can enhance the antioxidant enzyme activity of the grown rice, but also can increase the photosynthetic efficiency of the rice, and improve the plant height, dry weight and chlorophyll concentration of the rice under Cd stress and gas exchange properties, and relieve Cd-induced toxic effects by enhancing the physiological indicators of rice; in addition, during the vegetative growth stage of rice, Fe and Cd are absorbed by specific root transporters and transported to the aerial part through the xylem-phloem transport system, Soaking seeds with an appropriate concentration of iron can inhibit the expression of Cd transport genes OsIRT1, OsNRAMP1 and OsNRAMP5 in the xylem and phloem; in addition, soaking seeds with an appropriate concentration of iron can increase the phytochelatin (PC) in the cells of rice seedlings after growth, This helps to chelate Cd in the cell vacuole, thereby reducing the uptake of Cd by the rice plant, thereby reducing the
  • the concentration of selenium in the seed soaking agent is 4 to 6 mg/L, preferably 5 mg/L; the concentration of iron in the seed soaking agent is 3 ⁇ 5mg/L, preferably 4mg/L;
  • the source of the selenium element preferably includes Na 2 SeO 3 , the source of the iron element preferably includes FeSO 4 7H 2 O; the purity of the Na 2 SeO 3 is preferably greater than 99%;
  • the purity of the FeSO 4 7H 2 O is preferably greater than 98%;
  • the preparation method of the seed soaking agent preferably includes: mixing Na 2 SeO 3 and FeSO 4 7H 2 O with water to obtain the seed soaking agent; The method is not limited, and a mixing method well known to those skilled in the art can be used.
  • the present invention by soaking the rice seeds with a solution of selenium element and iron element at a suitable concentration, not only can the antioxidant enzyme activity of the grown rice be enhanced, and the resistance to heavy metals can be improved, but also the selenium element can remove superoxide anion and H2 O 2 , stimulate the activity of SOD and CAT, increase the level of oxygen excretion in rice roots, and iron can promote the formation of iron film on the root surface of rice roots; The formation of the film reduces the uptake of Cd by rice plants, thereby reducing the Cd content of rice.
  • the concentration of selenium in the seed soaking agent is 4 to 6 mg/L, preferably 5 mg/L; the concentration of silicon in the seed soaking agent is 1.5-5mmol/L, preferably 1.8-4mmol/L, more preferably 2mmol/L; the source of the selenium element preferably includes Na 2 SeO 3 , and the source of the silicon element preferably includes silicic acid; the source of the Na 2 SeO 3
  • the purity is preferably greater than 99%; the purity of the silicic acid is preferably greater than 99%;
  • the preparation method of the seed soaking agent preferably includes: mixing silicic acid with water and ultrasonic treatment to obtain a silicic acid suspension; mixing the silicic acid suspension with Na 2 SeO 3 are mixed to obtain the seed soaking agent; the present invention does not limit the mixing method, and the mixing method well known to those skilled in the art can be adopted.
  • Both the silicon element and the selenium element in the invention can effectively relieve the toxicity of Cd, and the silicon and selenium have a strong synergistic effect.
  • the present invention can promote the growth of rice plants by soaking the rice seeds with selenium and silicon solutions of suitable concentrations, reduce the content of malondialdehyde (MDA) in roots and shoots, and reduce the Cd transport factor; in addition, the compounding of silicon and selenium can Increased glutathione (GSH) content and phytochelatin (PC) content in root cell walls and organelles, causing PC-Cd to separate into vacuoles, and regulating the relative expression of OsNramp1 and OsHMA3 in rice, promoting Cd in cell walls and vacuoles Isolation, down-regulation of the relative expression of OsHMA2, inhibition of Cd transport, reducing the accumulation of Cd in rice seedlings, thereby sequestering Cd in the rice root cell wall and organelles, reducing the transfer of Cd to the shoots of rice
  • the concentration of selenium in the seed soaking agent is 4 to 6 mg/L, preferably 5 mg/L; the concentration of zinc in the seed soaking agent is 0.25 ⁇ 0.75mol/L, preferably 0.5mol/L;
  • the source of the selenium element preferably includes Na 2 SeO 3
  • the source of the zinc element preferably includes ZnSO 4 7H 2 O;
  • the purity of the Na 2 SeO 3 is preferably greater than 99%;
  • the purity of the ZnSO 4 7H 2 O is preferably greater than 99%;
  • the preparation method of the seed soaking agent preferably includes: mixing Na 2 SeO 3 and ZnSO 4 7H 2 O with water to obtain the seed soaking agent; the present invention
  • the mixing method There is no limitation on the mixing method, and a mixing method well known to those skilled in the art can be used.
  • the antagonism of zinc to Cd can reduce the ability of the seeds and rice plants to absorb and transport Cd, but also increase the antioxidant capacity of the rice plants, At the same time, by minimizing the generation of active oxygen and inhibiting the oxidative damage of cells, the resistance to heavy metals can be improved, thereby reducing the absorption and transport capacity of rice plants for Cd, thereby reducing the Cd content in rice.
  • the mass volume ratio of the seeds to the soaking agent is preferably 1g:(4-7)mL, more preferably 1g:5mL; the moisture content of the seeds before soaking is preferably 12%-14%.
  • the standing treatment to obtain the soaked seeds; the standing is preferably carried out in the dark, and the standing time is preferably 24 to 26 hours, more preferably 25 hours ;
  • the standing temperature is preferably 24-29°C, more preferably 25-27°C, most preferably 26°C.
  • the present invention After obtaining the soaked seeds, the present invention sows the soaked seeds, and obtains plants with strong Cd resistance after cultivation.
  • the germination treatment of the seeds is preferably carried out before sowing; the time of the germination treatment is preferably 3-5 days, more preferably 4 days.
  • the method of germination acceleration is not limited in the present invention, and the method of germination acceleration known to those skilled in the art can be adopted.
  • the sowing method preferably includes mechanical sowing, manual sowing, dry sowing, water sowing or transplanting after seedling raising.
  • the present invention not only reduces the absorption of Cd by the roots of the plants, but also reduces the translocation of Cd from the roots of the plants to other parts by mixing and soaking the rice seeds with a seed soaking agent containing appropriate concentrations of trace elements required by plants, thereby improving the tolerance of the plants.
  • the method of the present invention can obtain the rice that Cd content does not exceed standard with the lowest cost, the lightest operation method, makes brown rice Cd content in the paddy rice planted on Cd polluted soil significantly lower than food safety national standard/food
  • the pollutant limit standard is 0.2mg/kg, and at the same time save a lot of manpower and material resources, it is completely suitable for promotion and use in the field of heavy metal pollution prevention and control technology for rice and other bulk agricultural products in China.
  • the present invention also provides the application of the method described in the above scheme in reducing the Cd content of rice planted on Cd-polluted soil.
  • a light and simplified method for reducing rice cadmium content, the pot test of the method is as follows:
  • the pot experiment was set up in the greenhouse of the Institute of Botany, Chinese Academy of Sciences, Jiangsu province.
  • the soil used in the test is a paddy soil with excessive Cd, and the basic physical and chemical properties of the soil are shown in Table 1.
  • the soil Cd content is between the farmland soil Cd risk screening value and the control value, which belongs to the soil Cd light pollution, and more than 80% of the domestic paddy fields are Cd polluted fall within this range.
  • the tested rice variety Chuangliangyou 276 is the main variety in Jiangsu Province and belongs to the indica type two-line hybrid rice variety.
  • the rice seeds were first sterilized with 70% ethanol for 5 minutes, 5% sodium hypochlorite for 30 minutes, and then rinsed the seeds with sterile distilled water for 5 to 6 times ; SeO 3 solution, in which the selenium concentration is 1mg/L; the mass volume ratio of seeds and seed soaking agent is 1g:5mL) in a beaker, the top of the beaker is covered with clean paper, and then in the absence of light (25 ⁇ 1°C) After 24 hours, remove the seeds, wash the rice seeds 2-5 times with distilled water, and dry them by keeping them between two layers of filter paper and then drying them in bright sunlight until they become completely dry, i.e. ⁇ 10% of the original weight.
  • SeO 3 solution in which the selenium concentration is 1mg/L; the mass volume ratio of seeds and seed soaking agent is 1g:5mL
  • the seed soaking agent is a silicic acid suspension, wherein the silicon element concentration is 2mmol/L;
  • the preparation method of the seed soaking agent includes: mixing silicic acid with water and adding ultrasonic cleaning In the instrument, the temperature of the water bath is 30°C, and the ultrasonic treatment is performed for 7.5 hours to obtain the seed soaking agent.
  • Example 3 A method similar to Example 3, the only difference is that the concentration of silicon in the seed soaking agent is 4mmol/L.
  • Example 2 A method similar to Example 1, the only difference is that the seed soaking agent is clear water.
  • Example 1 and 2 and Comparative Examples 1 and 2 were repeated three times (3 pots).
  • harvest the roots, stems, leaves and grains of each pot of rice for each treatment wash the samples with deionized water, kill them at 105°C for 30 minutes, then dry them at 75°C to constant weight, weigh them, and crush them .
  • pulverized brown rice samples were digested with HNO3 - HClO4 in a hot plate until a clear solution was obtained, and then determined using inductively coupled plasma mass spectrometry (ICP-MS).
  • ICP-MS inductively coupled plasma mass spectrometry
  • the digestion process uses the analytical standard substance spinach (GBW10015), which is combined with the reagent blank analysis repetition to ensure the accuracy and precision of the digestion procedure.
  • the test results are shown in Table 2 and Figures 1-4.
  • the rice seed soaking agent of the present invention has a better effect when the water-soluble Se concentration is 1 to 5 mg/L, and the Cd content of rice grains is reduced to 0.06 to 0.1 mg/kg, which is significantly lower than
  • the national food safety standard/contaminant limit standard in food is 0.2mg/kg; and although the Cd content of rice grains in comparative example 2 is also lower than the national food safety standard, the Se element concentration in the soaking agent is too high, which will not only increase the production cost , but also have toxic effects on the growth of rice.
  • the rice seed soaking agent of the present invention has the best effect when the water-soluble Se concentration is 5mg/L, and the Cd content of rice roots is significantly lower than that of the blank control. It can be seen that the rice grown by seeds soaked in Se-containing solution can be reduced. Its uptake of Cd from the roots.
  • the rice seed soaking agent of the present invention has a better effect when the water-soluble Si concentration is 2mmol/L, and the Cd content of rice grains is reduced to 0.04mg/kg, which is significantly lower.
  • the national food safety standard is 0.2mg/kg.
  • the Cd content in the stem of the rice after treatment was significantly reduced by 43% to 80%.
  • the compounding method can be obtained, the rice seed soaking agent of the present invention has the best effect when the water-soluble Si concentration is 2mmol/L, and the Cd content of the rice stem is significantly lower than that of the blank control. content, it can be seen that rice grown from seeds soaked in Si-containing solution can reduce the transfer of Cd from root to stem in the body.
  • the rice seed soaking agent of the present invention has the best effect when the water-soluble Si concentration is 2mmol/L, and the Cd content of rice leaves is significantly lower than that of the blank control. It can be seen that after soaking in Si-containing solution Seed-grown rice can reduce the transport of Cd in its body to the aerial part.
  • the rice seed soaking agent of the present invention has a better effect when the water-soluble Zn concentration is 0.5mol/L, and the Cd content of rice grains is reduced to 0.018mg/kg, which is significantly lower than the food safety
  • the national standard is 0.2mg/kg.
  • rice seed soaking agent of the present invention is when water-soluble Zn concentration is 0.5mol/L, and effect is the best, and paddy leaf Cd content is significantly lower than the rice leaf Cd content of blank control, and it can be seen that the seed growth after soaking in Zn-containing solution rice can reduce the transport of Cd in its body to the aerial part.
  • Example 6 and Comparative Example 1 were analyzed by the same test method as the application example, and the test results are shown in Table 5 and Figures 13-16.
  • the rice seed soaking agent of the present invention is 4mg/L at water-soluble Fe concentration .
  • Se concentration is 5mg/L, the effect is the best, and the Cd content in rice grains is reduced to 0.061mg/kg, which is significantly lower than the national food safety standard of 0.2mg/kg.
  • the Cd content in the roots of the treated rice was significantly reduced by 57% to 74%.
  • the rice seed soaking agent of the present invention has the best effect when the water-soluble Fe concentration is 4mgl/L and the Se concentration is 5mg/L, and the Cd content in the rice root is significantly lower than that of the blank control. Rice grown from seeds soaked in solution can reduce its uptake of Cd from roots.
  • the Cd content in the stems of rice was significantly reduced after the treatment, with a drop of 36% to 74%.
  • the rice seed soaking agent of the present invention was When the concentration of water-soluble Fe is 4mgl/L and the concentration of Se is 5mg/L, the effect is the best, and the Cd content in the stem of rice is significantly lower than that of the blank control. It can be seen that the seeds soaked in the solution containing Fe and Se grow rice can reduce the transfer of Cd from root to stem in its body.
  • the Cd content of rice leaves after treatment is significantly reduced, with a drop of 31% to 79%.
  • the rice seed soaking agent of the present invention is When the concentration of water-soluble Fe is 4mgl/L and the concentration of Se is 5mg/L, the effect is the best, and the Cd content of rice leaves is significantly lower than that of the blank control. It can be seen that the rice grown from seeds soaked in Zn-containing solution Can reduce the transport of Cd in the body to the aerial part.
  • a light and simplified method for reducing cadmium content in rice, the field test of the method is as follows:
  • the test area is located in a polluted farmland in Guixi City, Jiangxi province (the total Cd content of the soil is 0.85mg/kg).
  • the main soil type in this area is paddy soil developed from river alluvial parent material.
  • the main pollutant is heavy metal Cd.
  • the basic physical and chemical properties of the soil are See Table 6. According to the Soil Environmental Quality Agricultural Land Soil Pollution Risk Control Standard (GB 15618-2018), the Cd content is between the farmland soil Cd risk screening value (0.3mg/kg) and the control value (1.5mg/kg), which belongs to the soil Cd light Moderate pollution, more than 80% of domestic paddy field Cd pollution falls within this range.
  • the specific treatment is as follows: In this experiment, a single-factor differential repeated design was adopted, and two kinds of rice were selected, namely, Chuangliangyou 276, which was verified effective in pot experiments, and Wuyou Huazhan, a commonly used local variety. Adopt seed soaking and germination treatment similar to Example 1, the only difference is that the seed soaking agent is different, 10 treatments are established altogether, 3 repetitions, a total of 30 plots, each plot area is 20m 2 (4m * 5m), arranged in random blocks , Each cell is separated by PVC boards to prevent the test results from being affected by rainwater runoff.
  • the experimental treatment is as follows:
  • the seed soaking agent in Table 7 represents that the seed soaking agent used in different treatments is the seed soaking agent in the corresponding examples or comparative examples.
  • Seeds were soaked and germinated according to the method in Example 1, and sowed, based on the dry weight of seeds before soaking, the amount of seeds sown was 0.1667kg/ha.
  • Control water content and fertilizers Level the arable land before sowing, apply 200kg/ha of urea, 480kg/ha of dipotassium hydrogen phosphate, keep flooding 2-3cm throughout the growth period, and other management measures are basically consistent with large-scale production.
  • the grain samples of rice in each plot of each treatment were harvested by the five-point sampling method, washed with deionized water, dried at 105°C for 30 minutes, dried at 75°C to constant weight, and weighed. smash.
  • Pulverized grain samples were digested with HNO3 - HClO4 on a hot plate until a clear solution was obtained, and then determined using inductively coupled plasma mass spectrometry (ICP-MS).
  • the digestion process uses the analytical standard substance spinach (GBW10015), which is combined with the reagent blank analysis repetition to ensure the accuracy and precision of the digestion procedure.
  • the test results are shown in Table 8, Figure 17 and Figure 18.
  • the paddy rice of the present invention has a significant effect when the concentration of water-soluble Se is 1mg/L, Si concentration is 2mmol/L, Zn concentration is 0.5mol/L, and Fe concentration is 4mg/L, and the Cd content of rice grains is lower than that of food safety countries. Standard 0.2mg/kg. It is consistent with the results of the pot experiment, so it can be inferred that it can be widely used.
  • the seed soaking agent in Table 9 represents that the seed soaking agent used in different treatments is the seed soaking agent in the corresponding examples or comparative examples.
  • Example 1 and Comparative Example 1 used the seed soaking agents to soak the seeds of different rice varieties for the Se content in the grains, and the measurement results are shown in Figure 20 and Table 10.
  • the seed soaking agent in Table 9 represents that the seed soaking agent used in different treatments is the seed soaking agent in the corresponding examples or comparative examples.
  • the rice seed soaking agent in the embodiment of the present invention 1 has no significant effect on the Se element content in the mature grain (brown rice), which is different from that in the pot experiment. The results were consistent.
  • the method of the present invention can not only reduce the absorption of Cd by the root of the plant, but also reduce the transport of Cd to other parts in the root of the plant by mixing and soaking the seed with the seed soaking agent containing the trace elements required by the plant at an appropriate concentration.
  • the method of the present invention can obtain the rice with Cd content not exceeding the standard with the lowest cost and the most convenient method, so that the Cd content of brown rice in rice planted on Cd-contaminated soil is significantly lower than that of food safety countries
  • the standard is 0.2mg/kg, while saving a lot of manpower and material resources, it is completely suitable for large-scale promotion and use in the field of heavy metal pollution prevention and control technology for bulk agricultural products such as rice in China.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Environmental Sciences (AREA)
  • Soil Sciences (AREA)
  • Botany (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Pretreatment Of Seeds And Plants (AREA)

Abstract

本发明涉及重金属污染防治领域，特别是涉及一种降低稻米镉含量的轻简化方法和应用。本发明提供一种降低稻米镉含量的轻简化方法，包括：将种子与浸种剂混合浸种，播种浸种后的种子，收获后得到Cd含量低的稻米；所述浸种剂的有效成分包括植物所需的微量元素；所述微量元素包括硒元素、硅元素、锌元素或铁元素，或硒元素和铁元素的混合物、硒元素和硅元素的混合物或硒元素和锌元素的混合物。本发明通过浸种的方法，将种子与浸种剂混合浸种后，采用常规方式种植，即可用低成本、操作便捷的方法获得Cd含量不超标的稻米。

Description

一种降低稻米镉含量的轻简化方法及应用
本申请要求于2021年05月24日提交中国专利局、申请号为CN202110563467.7、发明名称为“一种降低稻米镉含量的轻简化方法及应用”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本发明涉及重金属污染防治领域，特别是涉及一种降低稻米镉含量的轻简化方法和应用。
背景技术
Cd是生物体非必需元素，由于其具有高迁移性、高毒害性、高积累性和难消除性，被视为生物毒性最强的重金属。重金属Cd进入土壤后，由于其具有较高的生物活性，易被植物体吸收富集，同时随着食物链的放大，对人体健康产生威胁，包括导致骨质疏松、动脉硬化、引起肾脏损伤等。
水稻作为我国主要的粮食产物之一，土壤Cd污染会造成稻米Cd含量超标，进而对人体健康造成危害。可见控制稻米中的Cd含量，显得尤为重要。阻控稻米Cd超标的措施有很多，针对已经污染的土壤主要通过对其进行修复以达到安全生产的目的。针对农田Cd污染修复与治理比较有效的方法是施入土壤钝化材料，包括石灰、粉煤灰、羟基磷灰石、有机肥料等，进而提高土壤pH值，增加土壤吸附位点，降低土壤中Cd的活性，阻控水稻根部吸收。但由于Cd的生物迁移性很强，仍然会有一部分Cd离子被水稻根部吸收，继而迁移到茎、叶、籽粒中。另外，钝化材料随着施入时间的延长，钝化稳定性下降，土壤中的重金属Cd有可能重新活化，进而迁移到作物可食部分，特别是酸性水稻土由于酸沉降等原因更易被再次活化。
针对大面积重金属污染的农田，如何用最低成本、最便捷的方法获得Cd含量不超标的稻米是目前亟需解决的问题。
发明内容
为了解决上述问题，本发明提供了一种降低稻米镉含量的轻简化方法和应用，本发明的方法能够用较低成本、轻便的操作获得Cd含量不超标的稻米。
为了实现上述目的，本发明提供如下技术方案：
本发明提供了用于降低稻米镉含量的浸种剂，所述浸种剂的有效成分包括植物所需的微量元素，所述微量元素包括硒元素、硅元素、锌元素和铁元素中的一种，或铁元素、硅元素和锌元素中的一种与硒元素的混合物；
当所述微量元素为硒元素时，所述浸种剂中硒元素的浓度为0.5～6mg/L；
当所述微量元素为硅元素时，所述浸种剂中硅元素的浓度为1.5～5mmol/L；
当所述微量元素为锌元素时，所述浸种剂中锌元素的浓度为0.25～0.75mol/L；
当所述微量元素为铁元素时，所述浸种剂中铁元素的浓度为3～5mg/L；
当所述微量元素为硒元素和铁元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，铁元素的浓度为3～5mg/L；
当所述微量元素为硒元素和硅元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，硅元素的浓度为1.5～5mmol/L；
当所述微量元素为硒元素和锌元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，锌元素的浓度为0.25～0.75mol/L。
优选的，当所述微量元素包括硒元素时，所述硒元素的来源包括Na 2SeO 3；
当所述微量元素包括硅元素时，所述硅元素的来源包括硅酸；
当所述微量元素包括锌元素时，所述锌元素的来源包括ZnSO 4·7H 2O；
当所述微量元素包括铁元素时，所述铁元素的来源包括FeSO 4·7H 2O。
本发明提供一种降低稻米Cd含量的轻简化方法，包括：将种子与浸种剂混合浸种，播种浸种后的种子，收获后得到Cd含量低的稻米；所述浸种剂的有效成分包括植物所需的微量元素；所述微量元素包括硒元素、硅元素、锌元素或铁元素，或硒元素和铁元素的混合物、硒元素和硅元素的混合物或硒元素和锌元素的混合物；
当所述微量元素为硒元素时，所述浸种剂中硒元素的浓度为0.5～6mg/L；
当所述微量元素为硅元素时，所述浸种剂中硅元素的浓度为1.5～5mmol/L；
当所述微量元素为锌元素时，所述浸种剂中锌元素的浓度为0.25～0.75mol/L；
当所述微量元素为铁元素时，所述浸种剂中铁元素的浓度为3～5mg/L；
当所述微量元素为硒元素和铁元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，铁元素的浓度为3～5mg/L；
当所述微量元素为硒元素和硅元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，硅元素的浓度为1.5～5mmol/L；
当所述微量元素为硒元素和锌元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，锌元素的浓度为0.25～0.75mol/L。
优选的，所述种子与浸种剂的质量体积比为1g:(4～7)mL；所述种子的含水率为12％～14％。
优选的，当所述微量元素包括硒元素时，所述硒元素的来源包括Na 2SeO 3；
当所述微量元素包括硅元素时，所述硅元素的来源包括硅酸；
当所述微量元素包括锌元素时，所述锌元素的来源包括ZnSO 4·7H 2O；
当所述微量元素包括铁元素时，所述铁元素的来源包括FeSO 4·7H 2O。
优选的，当所述微量元素为硅元素时，所述浸种剂的制备方法包括：将硅酸与水 混合超声处理，得到浸种剂；
当所述微量元素为硒元素和硅元素的混合物时，所述浸种剂的制备方法包括：将硅酸与水混合超声处理，得到硅酸混悬液；
将硅酸混悬液与Na 2SeO 3混合，得到浸种剂。
优选的，所述超声处理的温度为30℃；所述超声处理的时间为7～8h。
优选的，种子与浸种剂混合后还包括静置处理；所述静置在黑暗中进行，所述静置的时间为24～26h，温度为24～29℃。
优选的，所述播种前还包括对浸种后的种子进行催芽处理；所述催芽处理的时间为3～5d。
优选的，种子与浸种剂混合前还包括对种子进行消毒处理；所述消毒的方法包括：
将种子用乙醇水溶液消毒后，再用次氯酸钠水溶液消毒，最后用无菌水漂洗；所述乙醇水溶液中乙醇的体积浓度为65％～75％；所述次氯酸钠水溶液中有效氯含量为5％～7％。
优选的，所述乙醇水溶液消毒的时间为4～6min；所述次氯酸钠水溶液消毒的时间为25～35min。
本发明还提供了上述方法在降低Cd污染土壤上种植的稻米Cd含量中的应用。
本发明的有益效果：本发明提供一种降低稻米镉含量的轻简化方法，包括：将种子与浸种剂混合浸种，播种浸种后的种子，收获后得到Cd含量低的稻米；所述浸种剂的有效成分包括植物所需的微量元素；所述微量元素包括硒元素、硅元素、锌元素或铁元素，或硒元素和铁元素的混合物、硒元素和硅元素的混合物或硒元素和锌元素的混合物；当所述微量元素为硒元素时，所述浸种剂中硒元素的浓度为0.5～6mg/L；当所述微量元素为硅元素时，所述浸种剂中硅元素的浓度为1.5～5mmol/L；当所述微量元素为锌元素时，所述浸种剂中锌元素的浓度为0.25～0.75mol/L；当所述微量元素为铁元素时，所述浸种剂中铁元素的浓度为3～5mg/L；当所述微量元素为硒元素和铁元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，铁元素的浓度为3～5mg/L；当所述微量元素为硒元素和硅元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，硅元素的浓度为1.5～5mmol/L；当所述微量元素为硒元素和锌元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，锌元素的浓度为0.25～0.75mol/L。本发明通过浸种的方法，将种子与所述浸种剂混合浸种，能够用最低成本、最轻便方法获得Cd含量不超标的稻米。
附图说明
图1为应用例1中不同处理籽粒Cd含量分析结果图；
图2为应用例1中不同处理水稻根部Cd含量分析结果图；
图3为应用例1中不同处理水稻茎部Cd含量分析结果图；
图4为应用例1中不同处理水稻叶部Cd含量分析结果图；
图5为应用例2中不同处理籽粒Cd含量分析结果图；
图6为应用例2中不同处理水稻根部Cd含量分析结果图；
图7为应用例2中不同处理水稻茎部Cd含量分析结果图；
图8为应用例2中不同处理水稻叶部Cd含量分析结果图；
图9为应用例3中不同处理籽粒Cd含量分析结果图；
图10为应用例3中不同处理水稻根部Cd含量分析结果图；
图11为应用例3中不同处理水稻茎部Cd含量分析结果图；
图12为应用例3中不同处理水稻叶部Cd含量分析结果图；
图13为应用例4中不同处理籽粒Cd含量分析结果图；
图14为应用例4中不同处理水稻根部Cd含量分析结果图；
图15为应用例4中不同处理水稻茎部Cd含量分析结果图；
图16为应用例4中不同处理水稻叶部Cd含量分析结果图；
图17为应用例5中创两优276品种在不同Se浓度浸种处理后籽粒中Cd的含量测定结果图；
图18为应用例5中五优占华品种在不同Se浓度浸种处理后籽粒中Cd的含量测定结果图；
图19为应用例6中不同Se浓度浸种处理后籽粒中Se的含量测定结果图；
图20为应用例7中不同品种分别在不同Se浓度浸种处理后籽粒中Cd的含量测定结果图。
具体实施方式
本发明提供一种降低稻米镉含量的轻简化方法，包括：将种子与浸种剂混合浸种，播种浸种后的种子，收获后得到Cd含量低的稻米；所述浸种剂的有效成分包括植物所需的微量元素；所述微量元素包括硒元素、硅元素、锌元素或铁元素，或硒元素和铁元素的混合物、硒元素和硅元素的混合物或硒元素和锌元素的混合物；当所述微量元素为硒元素时，所述浸种剂中硒元素的浓度为0.5～6mg/L；当所述微量元素为硅元素时，所述浸种剂中硅元素的浓度为1.5～5mmol/L；当所述微量元素为锌元素时，所述浸种剂中锌元素的浓度为0.25～0.75mol/L；当所述微量元素为铁元素时，所述浸种剂中铁元素的浓度为3～5mg/L；当所述微量元素为硒元素和铁元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，铁元素的浓度为3～5mg/L；当所述微量元素为硒元素和硅元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，硅元素的浓度为1.5～5mmol/L；当所述微量元素为硒元素和锌元素的混合物时，所述浸种剂中硒元素的浓度为 4～6mg/L，锌元素的浓度为0.25～0.75mol/L。
如无特殊说明，本发明对所述浸种剂中的各组分来源没有限定，采用本领域技术人员所熟知的市售商品即可。
本发明将种子与浸种剂混合浸种，得到浸种后的种子。在本发明中，种子与浸种剂混合前优选还包括对种子进行消毒处理；所述消毒的方法优选包括：将种子用乙醇水溶液消毒后，再用次氯酸钠水溶液消毒，最后用无菌水漂洗；所述乙醇水溶液中乙醇的体积浓度优选为65％～75％，更优选为70％；乙醇水溶液消毒的时间优选为4～6min，更优选为5min；所述次氯酸钠水溶液中有效氯含量优选为5％～7％，更优选为6％；次氯酸钠水溶液消毒的时间优选为25～35min，更优选为30min；所述漂洗的次数优选为5～6次。
在本发明中，当所述微量元素为硒元素时，所述浸种剂中硒元素的浓度为0.5～6mg/L，优选为1～5.5mg/L，更优选为5mg/L；所述硒元素的来源优选包括Na 2SeO 3；所述Na 2SeO 3的纯度优选大于99％；所述浸种剂的制备方法优选包括：将Na 2SeO 3与水混合，得到浸种剂；本发明对混合的方式没有限定，采用本领域技术人员所熟知的混合方式即可。
本发明通过将适宜浓度的硒元素溶液对水稻种子进行浸种处理，可以提高生长后的水稻根部和叶片的抗氧化酶(超氧化物歧化酶SOD、过氧化氢酶CAT和谷胱甘肽过氧化物酶GSH-Px)活性和脯氨酸(Pro)含量，并降低过氧化氢(H 2O 2)和丙二醛(MDA)含量，且有利于水稻根中不溶性Cd硒络合物的形成，由此降低了土壤溶液中生物有效态Cd含量，抑制了水稻对Cd的吸收和运输；此外，还可以提高水稻细胞的活性氧ROS，并使得线粒体膜电位降低，增加水稻植株木质素的含量和细胞壁的厚度；另外，硒元素浸种处理还可以降低水稻中Cd摄取相关基因(OsNramp5)和转运相关基因(OsLCT1)的表达，并激活了木质素合成相关基因(OsPAL、OsCoMT和Os4CL3)的表达，由此通过调节木质素合成和Cd相关基因的表达来降低水稻植株对于Cd的吸收和转运能力，进而降低稻米的Cd含量。
在本发明中，当所述微量元素为硅元素时，所述浸种剂中硅元素的浓度为1.5～5mmol/L，优选为1.8～4mmol/L，更优选为2mmol/L；所述硅元素的来源优选包括硅酸；所述硅酸的纯度优选大于99％；所述浸种剂的制备方法优选包括：将硅酸与水混合超声处理，得到浸种剂；所述超声处理的温度优选为30℃；所述超声处理的时间优选为7～8h，更优选为7.5h；所述超声处理的设备优选包括超声清洗仪。本发明对所述超声清洗仪的来源没有限定，采用本领域技术人员所熟知的市售商品即可。本发明通过超声处理，可以将硅酸均匀分散于水中。
本发明通过将适宜浓度的硅元素对水稻种子进行浸种，可以通过下调Cd转运基因 导致生长后的水稻对Cd的吸收和转运减少，并通过增强抗氧化酶活性，改善Cd诱导的氧化应激，降低Cd诱导的超氧化物歧化酶(SOD)，谷胱甘肽过氧化物酶(GSH-Px)和抗坏血酸过氧化物酶(APX)活性的增加，降低生长后的受Cd胁迫水稻的丙二醛(MDA)、过氧化氢(H 2O 2)和氧气(O 2)含量，缓解Cd诱导的氧化应激，同时提高水稻叶片叶绿素含量，提高根系活力，提高对重金属的抵抗能力，从而减轻水稻植株Cd的积累和毒性；此外，硅元素可以改善水稻的生长参数，保护水稻免受Cd毒性引起的细胞死亡和电解质渗漏，其通过促进水稻悬浮细胞的果胶合成、果胶甲基酯酶和阳离子交换能力，在重金属胁迫下维持细胞壁完整性发挥重要作用，由此使得水稻在根部保留Cd并限制Cd的向地上部转运。
在本发明中，当所述微量元素为锌元素时，所述浸种剂中锌元素的浓度为0.25～0.75mol/L，优选为0.5mol/L；所述锌元素的来源优选包括ZnSO 4·7H 2O；所述ZnSO 4·7H 2O的纯度优选大于99％；所述浸种剂的制备方法优选包括：将ZnSO 4·7H 2O与水混合，得到浸种剂；本发明对混合的方式没有限定，采用本领域技术人员所熟知的混合方式即可。
本发明通过将适宜浓度的锌元素溶液对水稻种子进行浸种，通过锌对Cd的拮抗作用降低种子和水稻植株对Cd的吸收和转运能力，同时可以增加成长后的水稻叶片中叶绿素a、b、a+b的含量，并增强超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性，降低丙二醛(MDA)含量，增加可溶性蛋白和可溶性糖的含量，由此提高水稻生长过程中的抗氧化物酶活性，减缓脂质过氧化作用，增强物质代谢水平，进而降低稻米的Cd含量。
在本发明中，当所述微量元素为铁元素时，所述浸种剂中铁元素的浓度为3～5mg/L，优选为4mg/L；所述铁元素的来源优选包括FeSO 4·7H 2O；所述FeSO 4·7H 2O的纯度优选大于98％；所述浸种剂的制备方法优选包括：将FeSO 4·7H 2O与水混合，得到浸种剂；本发明对混合的方式没有限定，采用本领域技术人员所熟知的混合方式即可。
本发明通过将适宜浓度的铁元素溶液对水稻种子进行浸种，不仅可以增强成长后水稻的抗氧化酶活性，而且可以增加水稻的光合效率，提高Cd胁迫下水稻的株高、干重、叶绿素浓度和气体交换属性，通过增强水稻的生理指标来缓解Cd诱导的毒性效应；另外，在水稻的营养生长阶段，铁、Cd被特定的根系转运体吸收，通过木质部-韧皮部转运***转运到地上部分，适宜浓度的铁元素浸种则可以抑制Cd在木质部和韧皮部运输基因OsIRT1，OsNRAMP1和OsNRAMP5的表达；此外，适宜浓度的铁元素浸种可以增加成长后的水稻幼苗细胞中的植物螯合素(PC)，这有助于与细胞液泡内的Cd螯合，由此可以降低水稻植株对于Cd的吸收，进而降低稻米的Cd含量。
在本发明中，当所述微量元素为硒元素和铁元素时，所述浸种剂中硒元素的浓度 为4～6mg/L，优选为5mg/L；所述浸种剂中铁元素的浓度为3～5mg/L，优选为4mg/L；所述硒元素的来源优选包括Na 2SeO 3，铁元素的来源优选包括FeSO 4·7H 2O；所述Na 2SeO 3的纯度优选大于99％；所述FeSO 4·7H 2O的纯度优选大于98％；所述浸种剂的制备方法优选包括：将Na 2SeO 3和FeSO 4·7H 2O与水混合，得到浸种剂；本发明对混合的方式没有限定，采用本领域技术人员所熟知的混合方式即可。
本发明通过将适宜浓度的硒元素和铁元素溶液对水稻种子进行浸种，不仅可以增强生长后水稻的抗氧化酶活性，提高对重金属的抵抗能力，而且硒元素可以通过清除超氧阴离子和H 2O 2，刺激SOD和CAT活性，提高水稻根系泌氧水平，铁元素可以促进水稻根系根表铁膜的形成；两种元素的复配可以通过增加水稻根中的根系泌氧，促进根表铁膜的形成，从而降低水稻植株对于Cd的吸收，进而降低稻米的Cd含量。
在本发明中，当所述微量元素为硒元素和硅元素时，所述浸种剂中硒元素的浓度为4～6mg/L，优选为5mg/L；所述浸种剂中硅元素的浓度为1.5～5mmol/L，优选为1.8～4mmol/L，更优选为2mmol/L；所述硒元素的来源优选包括Na 2SeO 3，硅元素的来源优选包括硅酸；所述Na 2SeO 3的纯度优选大于99％；所述硅酸的纯度优选大于99％；所述浸种剂的制备方法优选包括：将硅酸与水混合超声处理，得到硅酸混悬液；将硅酸混悬液与Na 2SeO 3混合，得到浸种剂；本发明对混合的方式没有限定，采用本领域技术人员所熟知的混合方式即可。本发明所述硅元素和硒元素均能有效缓解Cd的毒性，且硅和硒具有较强的协同效应。本发明通过将适宜浓度的硒元素和硅元素溶液对水稻种子进行浸种，可以促进水稻植株生长，降低根部和地上部丙二醛(MDA)含量，降低Cd转运因子；此外，硅硒复配可以增加根细胞壁和细胞器中谷胱甘肽(GSH)含量、植物螯合素(PC)含量，导致PC-Cd分隔成液泡，并调节水稻中OsNramp1和OsHMA3的相对表达，促进Cd在细胞壁和液泡中的隔离，下调OsHMA2的相对表达量，抑制Cd的运输，减少Cd在水稻幼苗中的积累，由此将Cd封存在水稻根细胞壁和细胞器中，减少Cd向水稻植株地上部的转移。
在本发明中，当所述微量元素为硒元素和锌元素时，所述浸种剂中硒元素的浓度为4～6mg/L，优选为5mg/L；所述浸种剂中锌元素的浓度为0.25～0.75mol/L，优选为0.5mol/L；所述硒元素的来源优选包括Na 2SeO 3，锌元素的来源优选包括ZnSO 4·7H 2O；所述Na 2SeO 3的纯度优选大于99％；所述ZnSO 4·7H 2O的纯度优选大于99％；所述浸种剂的制备方法优选包括：将Na 2SeO 3和ZnSO 4·7H 2O与水混合，得到浸种剂；本发明对混合的方式没有限定，采用本领域技术人员所熟知的混合方式即可。本发明通过将适宜浓度的硒元素和锌元素溶液对水稻种子进行浸种，不仅通过锌对Cd的拮抗作用降低种子和水稻植株对Cd的吸收和转运能力，而且可以增加水稻植株的抗氧化能力，同时通过最小活性氧的产生和抑制细胞的氧化损伤，提高对重金属的抵抗能力，从而降 低水稻植株对于Cd的吸收和转运能力，进而降低稻米中的Cd含量。
在本发明中，所述种子与浸种剂的质量体积比优选为1g:(4～7)mL，更优选为1g:5mL；所述种子浸种前的含水率优选为12％～14％。
在本发明中，种子与浸种剂混合后优选还包括静置处理，得到浸种后的种子；所述静置优选在黑暗中进行，所述静置的时间优选为24～26h，更优选为25h；所述静置的温度优选为24～29℃，更优选为25～27℃，最优选为26℃。
得到浸种后的种子后，本发明播种浸种后的种子，培育后得到耐Cd能力强的植株。在本发明中，所述播种前优选还包括对种子进行催芽处理；所述催芽处理的时间优选为3～5d，更优选为4d。本发明对所述催芽的方式没有限定，采用本领域技术人员所熟知的催芽方式即可。
在本发明中，所述播种的方式优选包括机械直播、手工直播、旱直播、水中直播或育秧后移栽。
本发明通过将水稻种子与含有适宜浓度的植物所需微量元素的浸种剂混合浸种，不仅可以减少植物根部对Cd的吸收，而且可以降低Cd在植物根部向其他部位的转运，从而提高植物的耐Cd能力；另外，本发明的方法能够用最低成本、最轻便的操作方法获得Cd含量不超标的稻米，使得在Cd污染土壤上种植的水稻中糙米Cd含量显著低于食品安全国家标准/食品中污染物限量标准0.2mg/kg，同时节省大量人力和物力，完全适合在我国水稻等大宗农产品重金属污染防治技术领域推广使用。
本发明还提供了上述方案所述的方法在降低Cd污染土壤上种植的稻米Cd含量中的应用。
为了进一步说明本发明，下面结合实施例对本发明提供的一种降低稻米镉含量的轻简化方法及应用进行详细地描述，但不能将它们理解为对本发明保护范围的限定。
实施例1
一种降低稻米镉含量的轻简化方法，该方法的盆栽试验具体如下：
盆栽试验设置在江苏省中国科学院植物研究所的大棚内。供试土壤为Cd超标的潴育型水稻土，土壤基本理化性质见表1。根据土壤环境质量农用地土壤污染风险管控标准(GB 15618-2018)，土壤Cd含量介于农田土壤Cd风险筛选值和管控值之间，属于土壤Cd轻度污染，国内80％以上的稻田Cd污染属于此范围内。供试水稻品种创两优276，是江苏省主推品种，属于籼型两系杂交水稻品种。将水稻种子先用70％乙醇表面灭菌5min，5％次氯酸钠表面灭菌30min，再用无菌蒸馏水漂洗种子5～6次；消毒后，将种子分别转移至含有浸种剂(浸种剂为Na 2SeO 3溶液，其中硒元素浓度为1mg/L；种子与浸种剂的质量体积比为1g:5mL)的烧杯中，烧杯顶部用干净的纸覆盖，然后在没有光(25±1℃)的情况下保持24h，24h后，取出种子，用蒸馏水清洗水稻种子2～5 遍，并通过保持在两层滤纸之间然后在明亮的阳光下干燥直至其变得完全干燥即初始重量的±10％来干燥；然后将干燥的种子置于覆盖有湿润滤纸的培养皿中催芽3d，待种子的芽大于2mm后进行播种。将发芽的种子播种至装有5kg供试土壤的塑料盆中(底径20cm×口径30cm×高20cm)，每盆种植三兜，每兜一株。控制水分含量和肥料：播种前每盆一次性施尿素2.5g，磷酸氢二钾1.0g，分别相对于大田1200kg/公顷和480kg/公顷，整个生育期保持淹水2～3cm，其它管理措施与大面积生产基本一致。
表1供试土壤基本理化性质
Figure PCTCN2021097651-appb-000001
实施例2
一种与实施例1相似的方法，唯一区别在于，浸种剂为Na 2SeO 3溶液，其中硒元素浓度为5mg/L。
实施例3
一种与实施例1相似的方法，唯一区别在于，浸种剂为硅酸混悬液，其中硅元素浓度为2mmol/L；所述浸种剂的制备方法包括：将硅酸与水混合加入超声清洗仪中，水浴温度30℃，超声处理7.5h，得到浸种剂。
实施例4
一种与实施例3相似的方法，唯一区别在于，浸种剂中硅元素浓度为4mmol/L。
实施例5
一种与实施例1相似的方法，唯一区别在于，浸种剂为ZnSO 4·7H 2O溶液，其中锌元素浓度为0.5mol/L。
实施例6
一种与实施例1相似的方法，唯一区别在于，浸种剂为FeSO 4·7H 2O和Na 2SeO 3的混合物溶液，其中硒元素浓度为5mg/L，铁元素的浓度为4mg/L。
实施例7
一种与实施例1相似的方法，唯一区别在于，浸种剂为Na 2SeO 3溶液和硅酸混悬液的混合液，其中硒元素浓度为5mg/L，硅元素的浓度为2mmol/L。
实施例8
一种与实施例1相似的方法，唯一区别在于，浸种剂为Na 2SeO 3和ZnSO 4·7H 2O的混合物溶液，其中硒元素浓度为5mg/L，锌元素的浓度为0.5mol/L。
实施例9
一种与实施例1相似的方法，唯一区别在于，浸种剂为FeSO 4·7H 2O溶液，其中铁元素的浓度为4mg/L。
对比例1
一种与实施例1相似的方法，唯一区别在于，浸种剂为清水。
对比例2
一种与实施例1相似的方法，唯一区别在于，浸种中硒元素浓度为20mg/L。
应用例1
将实施例1和2和对比例1和2四个浸种浓度分别进行三个重复(3盆)。于水稻成熟期，收获各处理的每盆水稻的根、茎、叶和籽粒，用去离子水冲洗后样品在105℃下杀青30min，然后在75℃下烘干至恒重，称重，粉碎。对于稻米Cd的分析，将粉碎的糙米样品用HNO 3-HClO 4在电热板中消解，直到得到澄清的溶液，然后使用电感耦合等离子体质谱ICP-MS进行测定。消解过程使用分析标准物质菠菜(GBW10015)，与试剂空白分析重复相结合，以保证消解程序的准确性和精确度。测试结果如表2和图1～4所示。
表2不同浸种浓度处理后水稻成熟期各部位Cd含量
Figure PCTCN2021097651-appb-000002
由表2和图1可以看出，在Cd污染(0.8mg/kg)土壤中，与不对水稻种子进行浸种处理的空白对照相比，处理后水稻籽粒Cd含量显著降低，降幅达49％～45％，另外对比不同的Se浸种浓度可得，本发明水稻浸种剂在水溶性Se浓度为1～5mg/L时，效果较佳，水稻籽粒Cd含量降低到0.06～0.1mg/kg，显著低于食品安全国家标准/食品中污染物限量标准0.2mg/kg；而对比例2中的水稻籽粒Cd含量虽然也低于食品安全国家标准，但是浸种剂中Se元素浓度过高，不仅会增加生产成本，而且也会对水稻的生长产生毒害作用。
由表2和图2可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻根部Cd含量明显降低，降幅达10％～76％，另外对比不同的Se浸种浓度可得，本发明水稻浸种剂在水溶性Se浓度为5mg/L时，效果最佳，水稻根部Cd含量显著低于空白对照的水稻根部Cd含量，可见经过含Se溶液浸泡后的种子生长的水稻可以减少其从根部对Cd的吸收。
由表2和图3可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻茎部Cd含量显著降低，降幅达53％～76％，另外对比不同的Se浸种浓度可得，本发明水稻浸种剂在水溶性Se浓度为1～5mg/L时，效果最佳，水稻茎部Cd含量显著低于空白对照的水稻茎部Cd含量，可见经过含Se溶液浸泡后的种子生长的水稻可以 降低Cd在其体内从根部向茎部的转移。
由表2和图4可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻叶部Cd含量显著降低，降幅达59％～78％，另外对比不同的Se浸种浓度可得，本发明水稻浸种剂在水溶性Se浓度为5mg/L时，效果最佳，水稻叶部Cd含量显著低于空白对照的水稻叶部Cd含量，可见经过含Se溶液浸泡后的种子生长的水稻可以降低Cd在其体内向地上部分的转运。
应用例2
与应用例相同的测试方法对实施例3、4和7和对比例1中的水稻及糙米进行分析，测试结果见表3和图5～8。
表3不同浸种浓度和方式处理后水稻成熟期各部位Cd含量
Figure PCTCN2021097651-appb-000003
由表3和图5可以看出，在Cd污染(0.8mg/kg)土壤中，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻籽粒Cd含量显著降低，降幅达46％～84％，另外对比不同的Si浸种浓度和复配方式可得，本发明水稻浸种剂在水溶性Si浓度为2mmol/L时，效果较佳，水稻籽粒Cd含量降低到0.04mg/kg，显著低于食品安全国家标准0.2mg/kg。
由表3和图6可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻根部Cd含量部分降低，降幅达1％～50％。
由表3和图7可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻茎部Cd含量显著降低，降幅达43％～80％，另外对比不同的Si浸种浓度和复配方式可得，本发明水稻浸种剂在水溶性Si浓度为2mmol/L时，效果最佳，水稻茎部Cd含量显著低于空白对照的水稻茎部Cd含量，结合各处理水稻中根部Cd含量，可见经过含Si溶液浸泡后的种子生长的水稻可以降低Cd在其体内从根部向茎部的转移。
由表3和图8可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻叶部Cd含量显著降低，降幅达59％～89％，另外对比不同的Si浸种浓度和复配方式可得，本发明水稻浸种剂在水溶性Si浓度为2mmol/L时，效果最佳，水稻叶部Cd含量显著低于空白对照的水稻叶部Cd含量，可见经过含Si溶液浸泡后的种子生长的水稻可以降低Cd在其体内向地上部分的转运。
应用例3
与应用例相同的测试方法对实施例5和8和对比例1中的水稻及糙米进行分析， 测试结果见表4和图9～12。
表4不同浸种方式处理后水稻成熟期各部位Cd含量
Figure PCTCN2021097651-appb-000004
由表4和图9可以看出，在Cd污染(0.8mg/kg)土壤中，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻籽粒Cd含量显著降低，降幅达61％～93％，另外对比不同的Zn浸种方式可得，本发明水稻浸种剂在水溶性Zn浓度为0.5mol/L时，效果较佳，水稻籽粒Cd含量降低到0.018mg/kg，显著低于食品安全国家标准0.2mg/kg。
由表4和图10可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻根部Cd含量显著降低，降幅达43％～55％。另外对比不同的Zn浸种方式可得，本发明水稻浸种剂在水溶性Zn浓度为0.5mol/L时，效果最佳，水稻根部Cd含量显著低于空白对照的水稻根部Cd含量，可见经过含Zn溶液浸泡后的种子生长的水稻可以减少其从根部对Cd的吸收。
由表4和图11可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻茎部Cd含量显著降低，降幅达72％～91％，另外对比不同的Zn浸种浓度方式可得，本发明水稻浸种剂在水溶性Zn浓度为0.5mol/L时，效果最佳，水稻茎部Cd含量显著低于空白对照的水稻茎部Cd含量，可见经含Zn溶液浸泡后生长的水稻可以降低Cd在其体内从根部向茎部的转移。
由表4和图12可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻叶部Cd含量显著降低，降幅达62％～96％，另外对比不同的Zn浸种方式可得，本发明水稻浸种剂在水溶性Zn浓度为0.5mol/L时，效果最佳，水稻叶部Cd含量显著低于空白对照的水稻叶部Cd含量，可见经过含Zn溶液浸泡后的种子生长的水稻可以降低Cd在其体内向地上部分的转运。
应用例4
与应用例相同的测试方法对实施例6和对比例1中的水稻及糙米进行分析，测试结果见表5和图13～16。
表5不同浸种方式处理后水稻成熟期各部位Cd含量
Figure PCTCN2021097651-appb-000005
由表5和图13可以看出，在Cd污染(0.8mg/kg)土壤中，与对水稻种子进行清水浸种处理的空白对照相比，本发明水稻浸种剂在水溶性Fe浓度为4mg/L、Se浓度为 5mg/L时，效果最佳，水稻籽粒Cd含量降低到0.061mg/kg，显著低于食品安全国家标准0.2mg/kg。
由表5和图14可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻根部Cd含量显著降低，降幅达57％～74％。另外，本发明水稻浸种剂在水溶性Fe浓度为4mgl/L、Se浓度为5mg/L时，效果最佳，水稻根部Cd含量显著低于空白对照的水稻根部Cd含量，可见经过含Fe与Se溶液浸泡后的种子生长的水稻可以减少其从根部对Cd的吸收。
由表5和图15可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻茎部Cd含量显著降低，降幅达36％～74％，另外，本发明水稻浸种剂在水溶性Fe浓度为4mgl/L、Se浓度为5mg/L时，效果最佳，水稻茎部Cd含量显著低于空白对照的水稻茎部Cd含量，可见经含Fe和Se溶液浸泡后的种子生长的水稻可以降低Cd在其体内从根部向茎部的转移。
由表5和图16可以看出，与对水稻种子进行清水浸种处理的空白对照相比，处理后水稻叶部Cd含量显著降低，降幅达31％～79％，另外，本发明水稻浸种剂在水溶性Fe浓度为4mgl/L、Se浓度为5mg/L时，效果最佳，水稻叶部Cd含量显著低于空白对照的水稻叶部Cd含量，可见经过含Zn溶液浸泡后的种子生长的水稻可以降低Cd在其体内向地上部分的转运。
应用例5
一种降低稻米镉含量的轻简化方法，该方法的大田试验具体如下：
试验区位于江西省贵溪市某污染的农田(土壤全Cd含量0.85mg/kg)，该区域主要土壤类型为河流冲积物母质发育的水稻土，其主要污染物是重金属Cd，土壤基本理化性质见表6。根据土壤环境质量农用地土壤污染风险管控标准(GB 15618-2018)，Cd含量介于农田土壤Cd风险筛选值(0.3mg/kg)和管控值(1.5mg/kg)之间，属于土壤Cd轻中度污染，国内80％以上的稻田Cd污染属于此范围内。
表6供试土壤基本理化性质
Figure PCTCN2021097651-appb-000006
具体处理如下：本试验采用单因子差异重复设计，选择两种水稻，分别为盆栽实验验证有效的创两优276以及当地常用品种五优华占。采用与实施例1相似的浸种和催芽处理，唯一区别在于浸种剂不同，共设10个处理，3次重复，共计30个小区，每小区面积为20m 2(4m×5m)，随机区组排列，各小区间PVC板隔开，防止因雨水径流 影响试验结果。实验处理如下：
表7试验处理示意表
组别 浸种剂 水稻品种
1 对比例1 创两优276
2 实施例1 创两优276
3 实施例3 创两优276
4 实施例5 创两优276
5 实施例9 创两优276
6 对比例1 五优华占
7 实施例1 五优华占
8 实施例3 五优华占
9 实施例5 五优华占
10 实施例9 五优华占
注：表7中浸种剂表示不同处理所用浸种剂为对应实施例或对比例中的浸种剂。
按实施例1中的方法浸种、催芽后进行播种，以浸种前的种子干重计，所述播种的种子用量为0.1667kg/公顷。控制水分含量和肥料：播种前对耕地进行平整，并施尿素200kg/公顷，磷酸氢二钾480kg/公顷，整个生育期保持淹水2～3cm，其它管理措施与大面积生产基本一致。
于水稻成熟期，采用五点采样法收获各处理的每个小区水稻的籽粒样品，用去离子水冲洗后样品在105℃下杀青30min，然后在75℃下烘干至恒重，称重，粉碎。将粉碎的籽粒样品用HNO 3-HClO 4在电热板中消解，直到得到澄清的溶液，然后使用电感耦合等离子体质谱ICP-MS进行测定。消解过程使用分析标准物质菠菜(GBW10015)，与试剂空白分析重复相结合，以保证消解程序的准确性和精确度。测试结果如表8、图17和图18所示。
表8不同浸种浓度处理后不同品种的水稻中籽粒Cd含量
Figure PCTCN2021097651-appb-000007
由表8图17和图18可以看出，在Cd污染(0.85mg/kg)大田土壤中，针对两个不同品种的水稻，与对水稻种子进行清水浸种处理的空白对照相比，本发明水稻浸种剂在水溶性Se浓度为1mg/L、Si浓度为2mmol/L、Zn浓度为0.5mol/L、Fe浓度为4mg/L时均有显著效果，并且使得水稻籽粒Cd含量低于食品安全国家标准0.2mg/kg。与盆栽实验结果一致，由此推断可推广使用。
应用例6
于水稻成熟期，分别收获实施例1、2、6、7、8和对比例1和2中不同浸种处理的每盆水稻的籽粒，采用GB5009.268-2016中的电感耦合等离子体质谱法(ICP-MS)，测定不同处理收获后籽粒中Se的含量，测定结果见图19和表9。
表9不同Se浓度浸种处理后籽粒中Se的含量
浸种剂 Se含量(μg/kg)
实施例1 33.89
实施例2 29.87
实施例6 31.25
实施例7 27.81
实施例8 33.31
对比例1 33.74
对比例2 74.82
注：表9中浸种剂表示不同处理所用浸种剂为对应实施例或对比例中的浸种剂。
由图19和表9可以看出，不同浓度的Se元素浸种后，只有在水溶性Se浓度为20mg/L(对比例2组)浸种时，才显著提高了籽粒中的Se元素含量；而且用适宜浓度的Se元素的溶液浸种处理后，收获的水稻籽粒(糙米)中Se元素的含量与对比例1中清水浸种方法的结果差异不显著。这是由于浸种后的水稻种子吸收Se元素后，将Se元素转化为内源性的有机Se，导致水稻吸收外源性的硒元素能力降低，因此对于低浓度的Se元素浸种处理来说，成熟后籽粒中的硒含量变化不显著；另外，浸种处理后的种子中的Se以有机Se的形态存在，无毒无害。
由盆栽试验可知，用适宜浓度的Se元素的溶液浸种处理后，收获得到的稻米对人体无健康风险。
应用例7
于水稻成熟期，采用五点采样法收获各处理的每个小区水稻的籽粒样品，采用GB5009.268-2016中的电感耦合等离子体质谱法(ICP-MS)，分别测定应用例5中采用实施例1和对比例1浸种剂分别浸种不同水稻品种处理后籽粒中Se的含量，测定结果见图20和表10。
表10 Se浸种后不同品种水稻籽粒中的Se含量
浸种剂 水稻品种 Se含量(μg/kg)
实施例1 创两优276 142.24
对比例1 创两优276 129.97
实施例1 五优华占 87.89
对比例1 五优华占 82.96
注：表9中浸种剂表示不同处理所用浸种剂为对应实施例或对比例中的浸种剂。
由图20和表10可以看出，在大田试验时，针对不同品种的水稻，本发明实施例1中的水稻浸种剂对于成熟后籽粒中(糙米)的Se元素含量影响不显著，与盆栽实验结果一致。而在2011年，根据《食品安全法》和《食品安全国家标准管理办法》的规定，经食品安全国家标准审评委员会审查通过，现决定取消《食品中污染物限量》(GB2762-2005)中硒指标(Se限量标准0.3mg/kg)；同时，作为人体和动物必需的Se，大部分稻米中Se含量在40μg/kg左右，低于我国食品卫生标准，根据我国平均食物消费结构，人均每年消费稻麦等谷类粮食作物206kg，设谷类全部为大米，则成人每天消费稻米0.564kg，通过计算可知，创两优276水稻品种浸种Se处理的稻米，成人每天的硒摄入量为80μg，远高于国家营养协会推荐的成人最低日摄入量40μg，更具有市场需求；另外，浸种处理后的种子中的Se以有机Se的形态存在，对人体无健康风险。
由大田试验可知，用适宜浓度的Se元素的溶液浸种处理后，收获得到的稻米对人体无健康风险，且营养价值更高。
综上所述，本发明的方法通过将种子与含有适宜浓度的植物所需微量元素的浸种剂混合浸种，不仅可以减少植物根部对Cd的吸收，而且可以降低Cd在植物根部向其他部位的转运，从而提高植物的耐Cd能力；另外，本发明的方法能够最低成本、最轻便的方法获得Cd含量不超标的稻米，使得在Cd污染土壤上种植的水稻中糙米Cd含量显著低于食品安全国家标准0.2mg/kg，同时节省大量人力和物力，完全适合在我国水稻等大宗农产品重金属污染防治技术领域大面积推广使用。
虽然本发明已以较佳的实施例公开如上，但其并非用以限定本发明，任何熟悉此技术的人，在不脱离本发明的精神和范围内，都可以做各种改动和修饰，因此本发明的保护范围应该以权利要求书所界定的为准。

Claims (12)

  1. 用于降低稻米镉含量的浸种剂，所述浸种剂的有效成分包括植物所需的微量元素，所述微量元素包括硒元素、硅元素、锌元素和铁元素中的一种，或铁元素、硅元素和锌元素中的一种与硒元素的混合物；
    当所述微量元素为硒元素时，所述浸种剂中硒元素的浓度为0.5～6mg/L；
    当所述微量元素为硅元素时，所述浸种剂中硅元素的浓度为1.5～5mmol/L；
    当所述微量元素为锌元素时，所述浸种剂中锌元素的浓度为0.25～0.75mol/L；
    当所述微量元素为铁元素时，所述浸种剂中铁元素的浓度为3～5mg/L；
    当所述微量元素为硒元素和铁元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，铁元素的浓度为3～5mg/L；
    当所述微量元素为硒元素和硅元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，硅元素的浓度为1.5～5mmol/L；
    当所述微量元素为硒元素和锌元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，锌元素的浓度为0.25～0.75mol/L。
  2. 根据权利要求1所述的浸种剂，其特征在于，当所述微量元素包括硒元素时，所述硒元素的来源包括Na 2SeO 3；
    当所述微量元素包括硅元素时，所述硅元素的来源包括硅酸；
    当所述微量元素包括锌元素时，所述锌元素的来源包括ZnSO 4·7H 2O；
    当所述微量元素包括铁元素时，所述铁元素的来源包括FeSO 4·7H 2O。
  3. 一种降低稻米镉含量的轻简化方法，其特征在于，包括：将种子与浸种剂混合浸种，播种浸种后的种子，收获后得到Cd含量低的稻米；所述浸种剂的有效成分包括植物所需的微量元素；所述微量元素包括硒元素、硅元素、锌元素或铁元素，或硒元素和铁元素的混合物、硒元素和硅元素的混合物或硒元素和锌元素的混合物；
    当所述微量元素为硒元素时，所述浸种剂中硒元素的浓度为0.5～6mg/L；
    当所述微量元素为硅元素时，所述浸种剂中硅元素的浓度为1.5～5mmol/L；
    当所述微量元素为锌元素时，所述浸种剂中锌元素的浓度为0.25～0.75mol/L；
    当所述微量元素为铁元素时，所述浸种剂中铁元素的浓度为3～5mg/L；
    当所述微量元素为硒元素和铁元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，铁元素的浓度为3～5mg/L；
    当所述微量元素为硒元素和硅元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，硅元素的浓度为1.5～5mmol/L；
    当所述微量元素为硒元素和锌元素的混合物时，所述浸种剂中硒元素的浓度为4～6mg/L，锌元素的浓度为0.25～0.75mol/L。
  4. 根据权利要求3所述的方法，其特征在于，所述种子与浸种剂的质量体积比为1g:(4～7)mL；所述种子的含水率为12％～14％。
  5. 根据权利要求3或4所述的方法，其特征在于，当所述微量元素包括硒元素时，所述硒元素的来源包括Na 2SeO 3；
    当所述微量元素包括硅元素时，所述硅元素的来源包括硅酸；
    当所述微量元素包括锌元素时，所述锌元素的来源包括ZnSO 4·7H 2O；
    当所述微量元素包括铁元素时，所述铁元素的来源包括FeSO 4·7H 2O。
  6. 根据权利要求5所述的方法，其特征在于，当所述微量元素为硅元素时，所述浸种剂的制备方法包括：将硅酸与水混合超声处理，得到浸种剂；
    当所述微量元素为硒元素和硅元素的混合物时，所述浸种剂的制备方法包括：将硅酸与水混合超声处理，得到硅酸混悬液；
    将硅酸混悬液与Na 2SeO 3混合，得到浸种剂。
  7. 根据权利要求6所述的方法，其特征在于，所述超声处理的温度为30℃；所述超声处理的时间为7～8h。
  8. 根据权利要求3所述的方法，其特征在于，种子与浸种剂混合后还包括静置处理；所述静置在黑暗中进行，所述静置的时间为24～26h，温度为24～29℃。
  9. 根据权利要求8所述的方法，其特征在于，所述播种前还包括对浸种后的种子进行催芽处理；所述催芽处理的时间为3～5d。
  10. 根据权利要求3所述的方法，其特征在于，所述种子与浸种剂混合前还包括对种子进行消毒处理；所述消毒的方法包括：
    将种子用乙醇水溶液消毒后，再用次氯酸钠水溶液消毒，最后用无菌水漂洗；所述乙醇水溶液中乙醇的体积浓度为65％～75％；所述次氯酸钠水溶液中有效氯含量为5％～7％。
  11. 根据权利要求10所述的方法，其特征在于，所述乙醇水溶液消毒的时间为4～6min；所述次氯酸钠水溶液消毒的时间为25～35min。
  12. 权利要求3～11任一项所述的方法在降低Cd污染土壤上种植的稻米Cd含量中的应用。
PCT/CN2021/097651 2021-01-15 2021-06-01 一种降低稻米镉含量的轻简化方法及应用 WO2022246880A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US17/617,334 US20240074439A1 (en) 2021-05-24 2021-06-01 LOW-LABOR INTENSITY AND SIMPLE METHOD FOR REDUCING Cd CONTENT OF RICE AND USE THEREOF
GB2204002.6A GB2610456A (en) 2021-01-15 2021-06-01 Simplified method for reducing cadmium of rice and use thereof

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202110563467.7 2021-05-24
CN202110563467.7A CN113261485A (zh) 2021-05-24 2021-05-24 一种降低稻米镉含量的轻简化方法及应用

Publications (1)

Publication Number Publication Date
WO2022246880A1 true WO2022246880A1 (zh) 2022-12-01

Family

ID=77232427

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/097651 WO2022246880A1 (zh) 2021-01-15 2021-06-01 一种降低稻米镉含量的轻简化方法及应用

Country Status (2)

Country Link
CN (1) CN113261485A (zh)
WO (1) WO2022246880A1 (zh)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114698644A (zh) * 2022-02-10 2022-07-05 湖南农业大学 含硅调节剂在农作物浸种中的应用以及浸种组合物和浸种方法

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103088089A (zh) * 2013-01-10 2013-05-08 伊犁川宁生物技术有限公司 一种阿卡波糖的发酵方法
CN103130325A (zh) * 2013-03-21 2013-06-05 哈尔滨工业大学 生物滤池的培养方法及地下水的水处理方法
CN103641118A (zh) * 2013-12-26 2014-03-19 南京林业大学 一种复合活化剂生产高比表面活性炭的生产方法
CN104904451A (zh) * 2015-05-12 2015-09-16 安徽太海粮油集团有限公司 富有机硒大米标准化种植方法
US20160289129A1 (en) * 2013-12-26 2016-10-06 Guangdong Institute Of Eco-Environmental And Soil Sciences (Guangdong Museum Of Soil Sciences) Selenium-doped nano silica sol used for producing selenium-enriched rice and capable of suppressing absorption and accumulation of heavy metals in paddy rice and preparation method therefor
CN106665222A (zh) * 2016-11-28 2017-05-17 全椒凤巢植保专业合作社 一种高产富硒水稻的种植方法
CN109863855A (zh) * 2019-03-15 2019-06-11 中国计量大学 提高镉胁迫下水稻种子发芽率的方法
CN110934152A (zh) * 2019-12-11 2020-03-31 浙江大学 一种降低水稻籽粒中镉砷含量的浸种剂及浸种方法
CN112624807A (zh) * 2021-01-14 2021-04-09 江西省农业科学院土壤肥料与资源环境研究所 一种水稻降镉药剂、浸种液及制备方法和浸种方法
CN112794768A (zh) * 2021-02-26 2021-05-14 中国科学院南京土壤研究所 一种降低水稻糙米镉含量的复合育秧剂及其应用

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105724428B (zh) * 2016-03-02 2017-02-22 广东省生态环境与土壤研究所（广东省土壤科学博物馆） 一种精准调控水稻镉吸收转运相关基因表达的叶面阻隔剂与应用
CN109349032A (zh) * 2018-09-28 2019-02-19 湖南金源种业有限公司 一种水稻育秧方法

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103088089A (zh) * 2013-01-10 2013-05-08 伊犁川宁生物技术有限公司 一种阿卡波糖的发酵方法
CN103130325A (zh) * 2013-03-21 2013-06-05 哈尔滨工业大学 生物滤池的培养方法及地下水的水处理方法
CN103641118A (zh) * 2013-12-26 2014-03-19 南京林业大学 一种复合活化剂生产高比表面活性炭的生产方法
US20160289129A1 (en) * 2013-12-26 2016-10-06 Guangdong Institute Of Eco-Environmental And Soil Sciences (Guangdong Museum Of Soil Sciences) Selenium-doped nano silica sol used for producing selenium-enriched rice and capable of suppressing absorption and accumulation of heavy metals in paddy rice and preparation method therefor
CN104904451A (zh) * 2015-05-12 2015-09-16 安徽太海粮油集团有限公司 富有机硒大米标准化种植方法
CN106665222A (zh) * 2016-11-28 2017-05-17 全椒凤巢植保专业合作社 一种高产富硒水稻的种植方法
CN109863855A (zh) * 2019-03-15 2019-06-11 中国计量大学 提高镉胁迫下水稻种子发芽率的方法
CN110934152A (zh) * 2019-12-11 2020-03-31 浙江大学 一种降低水稻籽粒中镉砷含量的浸种剂及浸种方法
CN112624807A (zh) * 2021-01-14 2021-04-09 江西省农业科学院土壤肥料与资源环境研究所 一种水稻降镉药剂、浸种液及制备方法和浸种方法
CN112794768A (zh) * 2021-02-26 2021-05-14 中国科学院南京土壤研究所 一种降低水稻糙米镉含量的复合育秧剂及其应用

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ZHANG QINGHUA, LIU ZHEN;ZHAO YUE-FENG: "Effects of Silicon on Mineral Element Accumulation and Physiological Characteristics of Watermelon Leaves", ANHUI NONGYE KEXUE (JOURNAL OF ANHUI AGRICULTURAL SCIENCES), ANHUI SHENG NONGYE KEXUEYUAN, CN, vol. 48, no. 1, 13 March 2020 (2020-03-13), CN , XP093006720, ISSN: 0517-6611, DOI: 10.3969/j.issn.0517-6611.2020.01.048 *

Also Published As

Publication number Publication date
CN113261485A (zh) 2021-08-17

Similar Documents

Publication Publication Date Title
Rezakhani et al. Phosphate–solubilizing bacteria and silicon synergistically augment phosphorus (P) uptake by wheat (Triticum aestivum L.) plant fertilized with soluble or insoluble P source
Clark et al. Differential Phosphorus Uptake by Phosphorus‐Stressed Corn Inbreds 1
CN105961104B (zh) 一种高sod含量水稻的种植方法、种植用肥料
CN104844313B (zh) 一种富硒樱桃番茄专用生物有机肥的制备方法
Rezakhani et al. Effect of silicon and phosphate-solubilizing bacteria on improved phosphorus (P) uptake is not specific to insoluble P-fertilized sorghum (Sorghum bicolor L.) plants
CN102206494B (zh) 一种能钝化菜地土壤重金属的改良剂及其制备方法和施用方法
CN108739253A (zh) 缓释型富硒园艺栽培基质及其制备方法和应用
CN110639946B (zh) 降低植株中重金属镉的方法
CN116478870A (zh) 一株嗜麦芽寡养单孢菌olr3-17菌株及其应用
CN110218678B (zh) 抗重茬土壤修复剂及其制备方法
WO2022246880A1 (zh) 一种降低稻米镉含量的轻简化方法及应用
CN114773113A (zh) 一种蘑菇菌棒有机硒生物肥料及其制备方法
Al-Omairi et al. Effect of soaking maize seeds with selenium and chitosan on improving germination, vigour and viability of seed and seedling
CN107027620B (zh) 一种同时富含硒和γ-氨基丁酸的植物的选育方法
Grewal et al. Zinc‐boron interaction effects in oilseed rape
Younes et al. Rice-husks synthesized-silica nanoparticles modulate silicon content, ionic homeostasis, and antioxidants defense under limited irrigation regime in eggplants
CN112974505A (zh) 一种活化剂协同固氮蓝藻修复稻田土壤镉污染的方法
CN107673916A (zh) 氧源超效全能生态负离子肥制取技术及使用方法
CN114766118B (zh) 肠杆菌m5在抑制水稻吸收积累镉砷的应用
CN113366945B (zh) 一种在中轻度镉污染农田边修复边安全种植玉米的间套作方法
US20240074439A1 (en) LOW-LABOR INTENSITY AND SIMPLE METHOD FOR REDUCING Cd CONTENT OF RICE AND USE THEREOF
CN114698644A (zh) 含硅调节剂在农作物浸种中的应用以及浸种组合物和浸种方法
CN115886002A (zh) 一种浸种液在缓解香稻幼苗砷胁迫和提高稻香方面的应用
CN108476956B (zh) 一种应用外源铁盐缓解镉对番茄毒害作用的水培方法及外源铁盐的应用
GB2610456A (en) Simplified method for reducing cadmium of rice and use thereof

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 17617334

Country of ref document: US

ENP Entry into the national phase

Ref document number: 202204002

Country of ref document: GB

Kind code of ref document: A

Free format text: PCT FILING DATE = 20210601

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21942451

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21942451

Country of ref document: EP

Kind code of ref document: A1