A kind of selenium-rich drop cadmium foliage silicon fertilizer and its preparation method and application
Technical field
The invention belongs to field of environment protection, are related to a kind of environmentally protective secondary nutrients and preparation method thereof, and in particular to
A kind of selenium-rich drop cadmium foliage silicon fertilizer and its preparation method and application.
Background technology
Stable soil fertility is the necessary condition of agricultural sustainable development, and soil nutrient supply balance is soil fertility
Important foundation.Silicon is the beneficial element of gramineous crop growth, it was reported that silicon can carry more than 30 kind crops in various degree
For reliable fertilizer efficiency, especially to the cereal crops such as rice, wheat class, it is of equal importance that siliceous fertilizer has been considered as N P and K by developed country
The fourth-largest main fertilizer point.In view of the chemical characteristic of silicon and its most compounds are insoluble, although there is a small amount of solubility
Object also receives a variety of factors limitation.Although silicon is the main component of soil, silicon is mostly very steady in soil
Fixed crystalline state and indefinite kenel, plant can not be absorbed and utilized.The intensivization development of agricultural, efficiently utilizing for soil have soil
The demand of effect silicon increasingly increases, and the micro element silicon of slow weathering has been unable to meet crops demand in soil.China is much
Has there are Available Silicon In Soils and has lacked symptom in area.China's siliceous fertilizer development is relatively slow, and the 1970s, mid-term just started siliceous fertilizer
Research, production and application to China's siliceous fertilizer nineties start to rapidly develop.According to incompletely statistics, existing siliceous fertilizer factory more than 40 of China
Family, more than annual production capacity 1000kt, yield 500kt or so, and calculated according to relevant expert, domestic siliceous fertilizer demand exists
More than 30000-40000kt, current country's annual output cannot meet for 1/10 the needs of.Therefore, siliceous fertilizer has in agricultural production
Wide application prospect.
In addition, China's heavy metal pollution of soil problem has been on the rise, very big prestige has been generated to the health of people
The side of body.According to statistics, contaminated nearly 1.5 hundred million mu of the cultivated area of China, sewage irrigation pollution are ploughed 32,500,000 mu at present, solid waste
2,000,000 mu of field is taken up an area and is ruined in object stockpiling, and total to account for about more than the 1/10 of total cultivated area, it is more flourishing to concentrate on economy for wherein majority
Area.The grain yield of reduction is up to 12,000,000 tons due to soil pollution every year, and direct economic loss is up to more than 200 hundred million yuan.Mesh
Before, substantially there are engineering control, biological treating, agricultural measures improvement, chemical harnessing etc. to the control measures of heavy metal pollution of soil.
Engineering control is mainly for the improvement of heavily contaminated soil;The methods of biological treating is then mainly used to slight pollution soil;These
Method carries out extensive remediation contaminated soil and often invests big but take effect small.
Document report applies silicon, selenium can reduce uptake and accumulation of the rice to elements such as heavy metal cadmium, arsenic, lead, chromium, improves
Rice preventing from heavy metal ability.Heavy metal pollution of soil problem be soil it is main be also most serious one of pollution problem, pass through
Plant itself is improved to heavy metal resistance, reduce to the absorption of heavy metal be heavy metal-polluted soil prevention new thinking, it is both economical
Safety again.And rice is improved to the resistance of heavy metal by increasing rice selemium nutrition, rice can be not only reduced to heavy metal
Uptake and accumulation, while the content of selenium in rice can be improved again, therefore, the research and development and application of selenium-enriched fertilizer receive extensive pass
Note, the mainly water-soluble blade face selenium-enriched fertilizer of domestic and international selenium-enriched fertilizer, the inorganic compound complex fertilizer of organic Se-rich, selenium-rich slow-release fertilizer
Material etc., although there are many patent of selenium-enriched fertilizer at present, most of is simply by inorganic selenite and fowl and animal excrement or agriculture
Industry waste is simply mixed or is prepared after microbial fermentation, the selenium-enriched fertilizer prepared using these methods, containing selenium
Measure relatively low, and selenite has bio-toxicity in itself, crop is damaged using conference was measured, using safety
It is poor, and using nano-silicon as carrier, activity height is prepared, the technique of safe and efficient selenium-rich foliage silicon fertilizer has not been reported.
Selenium is that one of necessary 14 kinds of trace elements of humans and animals that the World Health Organization generally acknowledges, achievement in research show generation
More than upper 40 million disease of boundary is all related with selenium deficiency.Selenium to anti-cancer, it is antitumor the effects that, China is there are about 72% regional selenium deficiency, people and dynamic
Selenium element in object is mostly derived from food, and the Se content insufficiency of intake of food source will influence the healthy growth of humans and animals, because
This, is by high-quality and efficient Se-rich farm products key technology research and integration and demonstration, to the crops selenium-rich such as grain, veterinary antibiotics,
Selenium-rich food is developed, the selenium element for supplementing needed by human body by food chain approach ensures people to a variety of diseases such as pre- anti-cancer
Health play an important roll.
But it is domestic or external, in addition to only a few research institution adding using Organic Selenium as Se-rich farm products
Add outside fertilizer, almost all of Se-rich farm products are derived from selenium-enriched area or use inorganic selenium as vegetable fertilizer, method
It applies, dress seed including root, pouring or the various ways such as foliage-spray.At present, also have it is more about the patent for preparing selenium-enriched foliage fertilizer,
But most selenium-enriched foliage fertilizer generally uses selenite on the market or selenite is fermented or complexing agent carries out later
Multiple foliage-spray.The fertilizer prepared using these technologies, first, selenium content is extremely low, and inorganic selenite is to have to dive in itself
Murder by poisoning risk, it is of high cost second is that the conversion ratio of agricultural product selenium is low;Third, the use process of foliar fertilizer has plant in itself
Burn seedlings risk, crop can be damaged by applying multi-dose, and safety is poor.
Inorganic selenium has better bioavailability and physiologic gain effect not as good as organic selenium compounds, in addition,
Compared with inorganic selenium, Organic Selenium is with the advantages that small toxicity, environmental pollution is small, and bioavailability is high.The gradual handle of people in recent years
Sight is turned on small toxicity and the high Organic Selenium of bioavailability.
Chitosan is one kind of polysaccharide, is woven with good biocompatibility, nontoxic, noresidue with animal groups, structure is easy
It is modified, moreover it is possible to improve or promote the absorption of trace element.Therefore, exploitation is used for the Organic Selenium chemical combination of high-quality and efficient Se-rich farm products
Object is the inexorable trend of selenium-rich industry development.
Invention content
To solve the disadvantage that the prior art and shortcoming, primary and foremost purpose of the invention is to provide a kind of selenium-rich drop cadmium leaf
The preparation method of face siliceous fertilizer.
Another object of the present invention is to provide one kind selenium-rich as made from above-mentioned preparation method to drop cadmium foliage silicon fertilizer, the fertilizer
Material can be used for reducing the crops heavy metal cadmium uptake and accumulations such as rice and production Se-rich farm products.
The object of the invention is achieved through the following technical solutions:
A kind of preparation method of selenium-rich drop cadmium foliage silicon fertilizer, includes the following steps:
(1) prepared by nanometer selenium:By the presoma selenous acid of nano particle or selenite in reducing agent, protective agent and solvent
It is reacted under the conditions of water is existing, wherein the molar ratio of the presoma of nano particle and reducing agent is 1:1~10, protective agent
1~5% for reaction solution volume;After reacting 1~3h, temperature rises to 50~60 DEG C of constant temperature and stirs 3~8h, with lye adjust pH to
4.0~6.0, obtain the nano selenium sol of good dispersion;
(2) prepared by chitosan selenium:Nano selenium sol made from step (1) is warming up to 50~60 DEG C, is rubbed by selenium/chitosan
Your ratio is 1:0.1~2 is added dropwise chitosan quaternary ammonium salting liquid, adjusts pH to 4.0~6.0 with lye, 30~60min of stirring to obtain the final product
Chitosan selenium product;
(3) it is 100 according to silicon/selenium molar ratio by chitosan selenium made from nano silicon dioxide sol and step (2):1~5
Ratio mixing, adjust pH to 7~8, selenium doping silicon dioxide colloidal sol be made, i.e., described selenium-rich drop cadmium foliage silicon fertilizer.
Step (1) described selenite is preferably sodium selenite, sodium hydrogen selenite or potassium selenite.
Step (1) described reducing agent is preferably at least one of sodium borohydride, ascorbic acid and hydroxylamine hydrochloride;The guarantor
It is preferably at least one of monohydric alcohol, dihydric alcohol and trihydroxylic alcohol, more preferably methanol or ethyl alcohol to protect agent.
The particle size range of step (3) described nano silicon dioxide sol is 5~20nm.
Step (3) described nano silicon dioxide sol is prepared by following steps:Using waterglass as raw material, handed over through ion
Change removal sodium ion, direct acidification reaction, prepare glue core, grain growth and etc. be made Ludox, then it is concentrated, remove heavy metal
Nano silicon dioxide sol is made.
Specifically, the nano silicon dioxide sol is prepared by the following method:
(A) using cation exchange resin, directly silicate solutions by multistage resin-column are filtered, are removed
Metal ion in silicate, while add in acid solution and be acidified, obtain active silicic acid solution of the pH value between 1~4;
(B) aqueous slkali is added drop-wise to active silicic acid solution under conditions of stirring, until pH stops drop when reaching 9~11
Add, silicic acid is made gradually to aggregate into silicon dioxide granule under alkaline condition, as the reaction time extends in growth course, silicon is molten
The grain size of glue is gradually increasing;After 2h is reacted, 10~40% alcohol of silica molal weight is incorporated as polymerization inhibitor,
Then 30 DEG C~90 DEG C are heated under the conditions of being stirred continuously, is maintained 5~12 hours, you can obtain a kind of low concentration of stable transparent
Alkaline silicon dioxide colloidal sol, is cooled to room temperature, and by low concentration alkaline silica sol by storng-acid cation exchange resin, repeats to add
Enter 10~40% alcohol of silica molal weight as polymerization inhibitor, be concentrated by ultrafiltration, obtain Ludox finished product;
(C) the chitosan quaternary ammonium salting liquid of Ludox finished-product volume percentage 0.5~2% is added in as chelating agent, 30
30~60min is stirred under~90 DEG C of controlled temperature conditions, then stands a period of time at this temperature, centrifugation, dialysis, adjustment colloidal sol pH
For 7 to get to the nano silicon dioxide sol of the high-purity neutrality of silica quality a concentration of 20~30%.
Its salt content of the impurity contents such as nano silicon dioxide sol heavy metal prepared by the present invention is far smaller than existing city
Ludox is sold, and product is stablized, 2 years are preserved without gel under room temperature.
Step (A) described acid solution is inorganic acid or organic acid, can be inorganic acid:Mainly sulfuric acid, nitric acid, hydrochloric acid,
Phosphoric acid etc. or organic acid:Such as formic acid, acetic acid, propionic acid, n-butyric acie.
Step (B) described aqueous slkali is sodium hydroxide solution, potassium hydroxide solution or sodium silicate solution etc..
Step (B) described polymerization inhibitor is monohydric alcohol, the one or more of dihydric alcohol, polyalcohol.
Active silicic acid preferably is added dropwise in aqueous slkali under the strong stirring state of 800~1200rpm rotating speeds in step (B)
Solution.
Step (C) described time of repose is 1~2h;The centrifugation refers to centrifuge 10min in 4000~6000 rotating speeds, can go
Except most of heavy metal ion;The dialysis refers to that by the silicon dioxide gel after centrifugation be 8KD~14KD with molecular cut off
Semi-permeable membrane carry out dialysis.
Heretofore described chitosan quaternary ammonium salting liquid is made by following steps:
The Chitosan powder of 1~10 mass parts deacetylation degree >=85% is dissolved in 50~500 parts by volume deionized waters,
Add in the acid such as formic acid, acetic acid, propionic acid, n-butyric acie, citric acid, lactic acid, hydrochloric acid, nitric acid of percent by volume 1~5% one kind or
Several to be dissolved into chitosan solution, it is 5.0 to adjust pH, and 1h is stirred in 30~80 DEG C, and it is 0.5~2% to be configured to mass concentration
Chitosan aqueous solution;ETA (2,3- glycidyl ammonium chloride) is added in into chitosan aqueous solution, it is chitosan to make its molar concentration
10~50%, 30~80 DEG C of reactions 8 of middle amino molar concentration~for 24 hours to get modified chitosan quaternary ammonium salting liquid.The shell gathers
Sugared modified material maintains antibiotic property and the moisture absorbability and moisture retentivity that chitosan has, and maintains the original good film forming of chitosan
Property.
Above-mentioned ETA refers to active cation etherifying agent EPTAC, is a kind of Multifunctional fine chemical products, its chemical name
Title is 2,3- epoxypropyltrimethylchloride chlorides【Referred to as ETA】, it is white solid under room temperature, soluble easily in water, meeting air can
Water suction is dissolved, molecular weight 151.5,140 DEG C of fusing point.
Cadmium foliage silicon fertilizer drops in selenium-rich made from above-mentioned preparation method, is made of nano silicon dioxide sol and chitosan selenium,
The weight content of chitosan selenium is 0.01%~1%.
Selenium-rich drop cadmium foliage silicon fertilizer can be used for reducing the absorption of the crops heavy metal cadmiums such as rice made from above-mentioned preparation method
Accumulation.
The present invention is using chitin modified material and chitosan selenium made from nanometer selenium selenizing effect, using nano-silicon as load
Body prepares activity height, safe and efficient selenium-rich foliage silicon fertilizer.Gained selenium-rich drop cadmium foliage silicon fertilizer appearance is clarified, is transparent or semi-transparent
Bright, Chinese red, sol system pH value is 7 or so;Grain size is generally in 20nm hereinafter, SiO in colloid2Mass concentration 20%~
30%, chitosan selenium mass concentration is below 1%.
Chitosan selenium in selenium-rich foliage silicon fertilizer of the present invention is Organic Selenium, and nano silicon dioxide sol is inorganic nano dioxy
SiClx colloidal sol.Silicon is special beneficial element, and the silicon nutrition of adjusting and controlling rice can improve the heavy metal resistance of crops, inhibit agriculture
Crop absorbs heavy metal.Since selenium has special physiological function again, resistance of the crops to heavy metal can be improved, therefore,
Selenium doping foliage silicon fertilizer is prepared, siliceous fertilizer product will be necessarily improved and inhibit crop heavy metal absorbent properties, while can produce again
The agricultural product of selenium-rich are obtained, that is, meet the production requirement of Se-rich farm products, and can be that China's heavy metals in farmland pollution control carries
For new thinking.
Compared with prior art, the present invention has the following advantages and beneficial effects:
(1) present invention is using chitin modified material and chitosan selenium made from nanometer selenium selenizing effect, with nano-silicon
For carrier, activity height, safe and efficient selenium-rich blade face silicon are prepared.Chitosan have good adsorptivity, film forming, permeability,
Hygroscopicity and moisture retention.Chitosan is the raw material of natural plant nutrient growth promoter-foliar fertilizer, the leaf formed by chitosan compounding
Leaven, necessarily will the moisturizing on blade face, film forming, nutrient is made more fully to be absorbed.Suitable selenium contributes to animal machine
Body health, it is excessive then be easy to cause person poultry poisoning.Selenium-rich drop cadmium foliage silicon fertilizer provided by the invention is safe and efficient, can both inhibit
Crop uptake and accumulation heavy metal, and crop edible part Se accumulation level can be improved.
(2) selenium doping silicon dioxide aerosol product performance produced by the present invention is stablized, and product is saturating for orange red (Chinese red)
Bright or translucent colloidal sol, pH can be widely applied to inhibit crop uptake and accumulation heavy metal, while improve edible portion close to neutrality
Position Se accumulation is horizontal, preferably guards the health of people, obtains better social and economic benefit.Nothing can be realized on a large scale
Public hazards industrialized production, in use, after above-mentioned selenium-rich siliceous fertilizer dilutes 100~200 times, available for soilless culture, also can directly by
It is suitable for farmland, Gen Shi or spray.
(3) in technical scheme of the present invention, inorganic states selenium is switched to have Organic Selenium, eliminates murder by poisoning risk;By nanometer
Selenium has carried out organic combination with chitin modified material, has been effectively promoted absorption and transfer of the rice to selenium element, improves
To the sorption enhanced utilization rate of its selenium.
(4) the obtained selenium-enriched foliage fertilizer (selenium doping silicon dioxide colloidal sol) of the present invention is not simple fermentation or complex liquid,
It is a kind of chelating Organic Selenium of stabilization, while in the case where the collaboration of nano active silicon promotes, improves the heavy metal resistance of crops.
The grain size of selenium doping silicon dioxide colloidal sol is small, generally less than 20nm, and grain size is single, sees Fig. 1;Selenium doping silicon dioxide colloidal sol
Concentration is high, and stability is good, places for a long time or is not in flocculent deposit after being diluted with water.
(5) technical method of the invention by increasing silicon, Se content in rice body, reaches the heavy metals such as barrier cadmium, arsenic
Entrance and migration, inhibit the heavy metals such as cadmium/arsenic from the distribution of regulation and control cauline leaf, transport protein activity, competition transport channel etc.
Absorption.Preparation method of the present invention is carried out in normal pressure, simple for process, easy to operation, thus is easy to be mass produced;It prepares
Raw material sources it is extensive, it is cheap, pollution it is small.
(6) the technology of the present invention method reduces cost of labor, the rice Se content that technical solution kind using the present invention goes out
Stablize in 0.2-0.4mg/kg, rice cadmium can reach safety standard 0.2mg/kg hereinafter, more healthy and safe.
Description of the drawings
Fig. 1 is the selenium doping silicon dioxide aerosol particle size distribution map that Se content is 1g/L.
Fig. 2 is the selenium doping silicon dioxide colloidal sol ultraviolet-visible spectrum absorption figure that Se content is 1g/L.
Fig. 3 is the selenium doping silicon dioxide colloidal sol infrared spectrum that Se content is 1g/L.
Fig. 4 is that various concentration selenium adulterates influence of the Ludox to Cd concentration of brown rice.
Fig. 5 is the influence for spraying different selenium doping colloidal sols to rice Se content.
Fig. 6 is root Si/Cd absorption and transport gene expression analysis patterns.
Specific embodiment
With reference to embodiment and attached drawing, the present invention is described in further detail, but embodiments of the present invention are unlimited
In this.
The materials, reagents and the like used in the following examples is commercially available unless otherwise specified.
Chitosan quaternary ammonium salting liquid described in following embodiments is made by following steps:
The Chitosan powder that 2g deacetylations degree is 95% is dissolved in 200ml deionized waters, adds in percent by volume 3%
N-butyric acie be dissolved into chitosan solution, it is 5.0 to adjust pH, and 1h are stirred in 50 DEG C, is configured to the chitosan that mass concentration is 1%
Aqueous solution;ETA (2,3- glycidyl ammonium chloride) is added in into chitosan aqueous solution, makes its molar concentration for amino in chitosan
The 30% of molar concentration, 50 DEG C of reaction 12h are to get modified chitosan quaternary ammonium salting liquid.It is anti-to maintain that chitosan has for it
Bacterium property and moisture absorbability and moisture retentivity, and maintain the original good film forming of chitosan.
Embodiment 1:Prepare nano silicon dioxide sol
(1) SiO is chosen2/Na2The sodium metasilicate of O molar ratios 3.2 is configured to the sodium silicate solution that mass concentration is 10%
500ml, magnetic agitation 1h under room temperature;Directly silicate solutions by multistage resin-column are filtered, remove silicate
In metal ion, while add in mass concentration be 5% hydrochloric acid solution 150ml be acidified, control column mouth collect filtrate i.e.
It can obtain active silicic acid aqueous solution of the pH value between 1~4.
(2) 0.5M sodium hydroxide solutions are prepared, are added dropwise to step (1) dropwise under the strong stirring state of 1000rpm rotating speeds
In the active silicic acid aqueous solution obtained, until pH reaches 10, stop being added dropwise, silicic acid is made gradually to aggregate into two under alkaline condition
Silicon oxide particle, as the reaction time extends in growth course, the grain size of Ludox is gradually increasing, and after 2h is reacted, adds
Enter amount be silica molal weight 20% ethyl alcohol as polymerization inhibitor, arrived under the conditions of being then stirred continuously using heating water bath
It 60 DEG C, maintains 8 hours, you can obtain a kind of low concentration alkalinity silicon dioxide gel of stable transparent;Low concentration alkalinity silicon is molten
Glue is by storng-acid cation exchange resin, and using concentration, 20% ethyl alcohol for repeating to add in silica molal weight is made
It is concentrated 2 times for polymerization inhibitor, ultrafiltration concentration process, is prepared into the acidic silicasol finished product that silica quality score is 25%;
(3) chitosan quaternary ammonium salting liquid of the acidic silicasol finished-product volume than 1% is added in as chelating agent, in 60 DEG C of temperature controls
Under the conditions of stir 60min, then static 2h at this temperature, 5000 rotating speed of centrifuge centrifugation 10min can remove a most of huge sum of money
Belong to ion, then silicon dioxide gel is subjected to dialysis with the semi-permeable membrane that molecular cut off is 8KD~14KD, remove remaining huge sum of money
The foreign ions such as category, adjustment colloidal sol pH are 7 to get the nano-silica of high-purity neutrality for being 25% to silica quality score
SiClx colloidal sol.
Its salt content of the impurity contents such as nano silicon dioxide sol heavy metal prepared by the present invention is far smaller than existing city
Ludox is sold, and product is stablized, preserve 2 years without gel under room temperature, pH value is substantially unchanged, and detection data is as shown in table 1.
1 nano silicon dioxide sol of the present invention of table and the impurity ion content of commercially available nano silicon dioxide sol compare
Embodiment 2:Prepare chitosan selenium solution
(1) prepared by precursor liquid
0.5g sodium selenites is taken to be dissolved in 250ml distilled water, 2.5g ethyl alcohol is added in as protective agent, stirs 20min, then
The direct insertion processor of ultrasonic wave is inserted into the solution of uniform stirring, ultrasonic intensity 800KHZ, ultrasonic wave, which starts, prepares drop
Add reducing agent solution;
(2) reducing agent adds in
Weigh 0.2g sodium borohydrides add water 200ml dissolve after, precursor liquid made from step (1) is added dropwise under ultrasound condition
In prepare crystal seed, then be added dropwise ascorbic acid, hydroxylamine hydrochloride mixed liquor 50ml (ascorbic acid in mixed liquor, hydroxylamine hydrochloride it is dense
Degree is all 0.04mol/L) as the reducing agent in production process, after reacting 2h, temperature rises to 55 DEG C of constant temperature stirring 5h, adjusts pH
It is 5.0, obtains good dispersion nano selenium sol product at this time;
(3) prepared by chitosan selenium
It is 1 by selenium/chitosan molar ratio:2 rapid dropwise addition chitosans, adjust pH to 5.0 with lye, stir 60min, treat
Color becomes orange red and no longer changes colour to get chitosan selenium solution.
Embodiment 3:Prepare selenium doping silicon dioxide colloidal sol
Chitosan selenium solution prepared by nano silicon dioxide sol and embodiment 2 prepared by embodiment 1, respectively with selenium/
Silicon mol ratio is 1:100、2:100、3:100、4:100、5:100 ratio is mutually dissolved, and is mixed, absorption, and pH is adjusted with lye
The Organic Selenium doping silicon dioxide colloidal sol of different levels of doping is formed to 7.Selenium/silicon mol ratio is 1:100、2:100、3:100、
4:100、5:Organic Selenium doping silicon dioxide colloidal sol Se content made from 100 respectively be 0.5g/L, 1.0g/L, 1.5g/L,
2.0g/L、2.5g/L.Wherein, the selenium doping silicon dioxide aerosol particle size distribution that Se content is 1g/L is as shown in Figure 1, selenium doping is multiple
The grain size for closing Nano silica sol is small, generally less than 20nm, and grain size is single.The colloidal sol infrared spectrum and purple synthesized using this method
Outside-visible spectrogram is as shown in the figure.Fig. 2 is the selenium doping silicon dioxide colloidal sol ultraviolet-visible spectrum absorption figure that Se content is 1g/L,
Fig. 3 Se contents are the selenium doping silicon dioxide colloidal sol infrared spectrum of 1g/L.
Embodiment 4:Foliage-spray selenium doping Ludox reduces heavy metal uptake by rice field experiment effect
Enforcement place:The contracted fields such as one directorial area Cheng Xiu treasure of Zhaoqing City of Guangdong Province Dinghu District Sha Pu towns peach carry out, experimental field
For rice soil, soil property is sandy loam, and middle fertility, preceding crop is rice, and experiment test plant is rice, and kind is Guangdong show
It accounts for.
Physiochemical properties of soil is as shown in table 2:
2 physiochemical properties of soil of table
Organic matter g/kg |
Full nitrogen g/kg |
Alkali-hydrolyzable nitrogen mg/kg |
Available phosphorus mg/kg |
Available potassium mg/kg |
pH |
Total cadmium mg/kg |
20.0 |
1.1 |
97.0 |
80.5 |
88.0 |
6.6 |
125.2 |
The method of field rice foliage-spray selenium doping silicon dioxide colloidal sol:
Spraying time:During which rice tillering peak period continuously sprays twice, every minor tick 7-10 days or so is dilute to the jointing stage
Release 100 times of progress foliage-sprays, it is desirable that sprayed after at 4 points in fine day afternoon, spraying in 24 hours needs to fill spray if rainy one
It is secondary;It is required that thinned water cannot have heavy metal pollution, preferably with drinking water, if with irrigation water, water quality has to reach filling
Irrigate water water quality requirement standard.
Spray metering:(selenium mixed with nano-silicon dioxide is molten for series concentration gradient secondary nutrients prepared by embodiment 3
Glue) processing, silicone content >=100g/L, Se content is respectively 0.5g/L, 1.0g/L, 1.5g/L, 2.0g/L, 2.5g/L, in water
Rice tillering regularity carries out the foliage-spray of 1 secondary nutrients to the jointing stage.1 moderate-element fertilizer is carried out in the grouting middle and later periods
Spraying for material, sprays altogether 2 times;First time sprayed dose is 1L/ mus, and second of sprayed dose is 1.2L/ mus;It is watered dilution
Foliar spray is carried out after 100 times, to spray equivalent clear water as control, experiment using field plot is designed, set altogether at 6 CK
Reason each handles 3 repetitions, random district's groups arrangement;
Field management:Conventional field management after rice maturation harvests, analyzes each cell brown rice cadmium and Se content, as a result
As shown in Figures 4 to 6.
Show that foliage-spray various concentration selenium is mixed as shown in figure 4, being tested in Zhaoqing Dinghu District Sha Pu towns peach with directorial area
After miscellaneous nano silicon dioxide sol, absorption and accumulation of the rice to cadmium can be significantly inhibited, and increase rice Se content;With selenium
The increase of doping, rice Se content dramatically increases, and Cd concentration of brown rice is then remarkably decreased.Compared with the control, blade face is sprayed respectively
Se content is applied as 0.5g/L, 1.0g/L, 1.5g/L, 2.0g/L, 2.5g/L (number respectively is 1#, 2#, 3#, 4#, 5#) selenium
After dopen Nano Ludox, Cd concentration of brown rice has dropped 49.2%, 67.8%, 70.4%, 70.8%, 71.2% respectively.
As shown in figure 5, wherein when selenium doping concentration reaches 1.0g/L, 1.5g/L, 2g/L, the content of selenium is not in rice
0.12mg·kg-1、0.18mg·kg-1、0.26mg·kg-1, meet selenium-rich rice standard (GB/T22499-2008).But selenium
When doping concentration is 0.5g/L, Se content is only 0.08mgkg in rice-1, when selenium doping is 2.5g/L, selenium in rice
Content be 0.38mgkg-1, it has been more than selenium-rich rice Se content standard (GB/T22499-2008).Therefore, in Zhaoqing ancient cooking vessel
Lake region Sha Pu towns peach passes through foliage-spray selenium dopen Nano Ludox containing 1.0g/L, 1.5g/L, 2.0g/L, Ke Yi with directorial area
Cadmium content selenium-rich rice up to standard is produced on Cd-polluted farmland.
Our patents early period:A kind of blade face barrier of control accurate rice Cd uptake transhipment related gene expression and application
Research【CN 105724428 A】, analysis obtain key gene from rice leaf to seed that transport from of control cadmium including OsLsi1,
OsLsi2, OsHMA3, OsNramp5 and OsLCT1, as shown in fig. 6, in addition to 1#, foliage-spray is to the table of Cd absorption and transport genes
Up to nearly all there is apparent inhibiting effect.And it sprays 2#, 3#, 4# and can also significantly lower the expression of OsLsi1 and OsLsi2.
Above-described embodiment is the preferable embodiment of the present invention, but embodiments of the present invention are not by above-described embodiment
Limitation, other any Spirit Essences without departing from the present invention with made under principle change, modification, replacement, combine, simplification,
Equivalent substitute mode is should be, is included within protection scope of the present invention.