KR20190023189A - Use of graphene as an active ingredient for plant growth promotion - Google Patents

Abstract

Provided is a novel use of graphene as an active ingredient to promote eco-friendly plant growth, wherein graphene promotes the growth of trees while minimizing adverse effects due to overuse of conventional chemical fertilizers and also increases the production of crops. The inventors of the present invention have confirmed that the germination and growth of plants are significantly improved by applying graphene to herbaceous plants and woody plants in a manner of spraying the same to a side surface or soil. In addition, a graphene component, either mixed in soil or absorbed in plants, can help promote the metabolism of plants by making the germination and growth of plants proper even in barren soil where plants do not grow well such as soil in which salt is accumulated or in soil imbalanced in nutrients.

Description

USE OF GRAPHENE AS AN ACTIVE INGREDIENT FOR PLANT GROWTH PROMOTION AS ACTIVE INGREDIENT FOR INCREASING PLANT GROWTH [0002]

This invention relates to a novel use of graphene for promoting plant growth. The graphene according to the present invention can be provided in the form of being incorporated into the soil or absorbed by the plant, acting as an active ingredient for promoting the germination and growth of the plant, and further improving the soil in the long term.

In recent years, demand for agricultural products has increased rapidly due to the increase in global population and the preference for high quality food. However, due to the spread of environmental pollution and global warming, the cultivation environment of crops is getting worse. As a result, the use of chemical fertilizers and pesticides is gradually increasing, and it is also known that acidification of farmland and excessive accumulation of salt in soil cause devastation of agricultural land.

To overcome this problem, improvement of crop seed, organic farming using compost, application of fertilizer containing a component emitting far-infrared rays, application of fertilizer containing a minor component of minerals, application of soil microorganisms, and the like have been proposed .

Despite these efforts, however, the use of such materials, which are used as an alternative to the use of chemical fertilizers, also has problems similar to the side effects of chemical fertilizer fertilization.

As another alternative, a method of using a composition containing nano-sized particles has recently been proposed (Patent Publication No. 10-2017-0067440). Specifically, the use of nanoparticles containing a metal component such as iron, calcium, or magnesium or a metal oxide component.

Also, the use of a fertilizer composition containing nanoparticles containing carbon as a main component has been reported. One example is the use of graphene, a nanoparticle based on carbon, according to WO 2015/066691. According to this method, the use of a fertilizer composition in the form of graphening the surface of a conventional chemical fertilizer such as potassium nitrate is used to slowly release the components of the chemical fertilizer from the surface, thereby improving the effect of fertilizer use. In this report, however, there is no mention of the effect that graphene itself acts as an active ingredient to promote plant germination and growth. In this report, graphene only describes the effect of controlling the rate of release of chemical fertilizer components into the soil.

KR 10-2017-0067440 A (June 16, 2017) WO 2015/066691 A (2015/05/07)

In view of the above-mentioned problems, the present invention provides a novel use of graphene as an active ingredient of an eco-friendly plant growth promoter, which can promote the growth of trees and increase the production of crops while minimizing adverse effects due to overuse of chemical fertilizers The purpose is to provide.

To accomplish this task, we have observed grape growth and the growth and germination of crops as a result of incorporating graphene into the soil around the plant or as a solution diluted in water on the side of the plant. Respectively. As a result, it has been confirmed that graphene acts as a main active ingredient for accelerating the germination and growth of plants in a state of being incorporated into the soil or absorbed by the plant. Thus, the present invention has been completed.

Therefore, the present invention is characterized by a composition containing graphene as an active ingredient for promoting plant growth.

The graphene preferably has an average thickness of 1 to 20 atomic layers and an average plane size of 0.02 to 20 탆.

The graphene produced according to the present invention is adsorbed in a water-diluted aqueous solution or in a talc powder to be sprayed on the sides of various plants including herbaceous plants and woody plants or sprayed on soil, And the growth of leaves and stems was significantly enhanced. According to the present invention, the inventive graphene grafted to a plant and its surrounding soil can be used to prevent germination and growth of a plant even in an unfavorable soil environment in which plants do not grow well, such as a soil with salt accumulation or an imbalance of nutrients It is expected that it will act as a major active ingredient for long-term soil improvement by promoting the metabolism of plants to be done normally.

Fig. 1 is an image taken on Aug. 24, 2017 of a goat farm where the Example 2 was carried out.
FIG. 2 is an image taken on Aug. 24, 2017 of the goat farm where the Comparative Example 1 was carried out.

This invention provides the use of graphene as an active ingredient for promoting plant growth.

The graphene includes graphene produced by a CVD method or a physical stripping method, graphene oxide (GO) produced by a chemical stripping method, and reduced graphene oxide (rGO) produced by reducing the graphene oxide can do.

According to the present invention, graphene may be provided in the form of an aqueous solution diluted with water in a dispersed state, and may also be provided in a form adsorbed to an inorganic mineral powder such as talc.

Hereinafter, the present invention will be described in detail.

Examples of graphenes that can be used in the present invention include graphene and graphene oxide which are produced mechanically or chemically by peeling graphite in a top-down manner, or reduced graphene obtained by reducing the graphene oxide Oxide. In addition, as another example of graphene that can be used in the present invention, a carbon-containing material such as graphite or a hydrocarbon compound is used as a raw material and is produced in a bottom-up manner by chemical vapor deposition Graphene can be heard.

Generally, the graphene or graphene oxide obtained in a top-down manner has a chemical structure with mainly a multi-layered carbon layer, and the graphene obtained in a bottom-up manner has a chemical structure close to that of a carbon single layer. When a special synthesis process of a large area graphene is excluded, the lateral size of the graphene obtained by the above two methods can be widely distributed from several tens nm to several tens of microns.

In order to reduce the average thickness (represented by the number of carbon layers) of the graphene synthesized by the above method and the average plane size, the graphene raw material is dispersed in a dispersion solvent and then subjected to ultrasonic treatment or ball mill treatment, And the subsequent classification process can be used.

The preferred size of graphene as an active ingredient for promoting plant growth is an average thickness of 1 to 20 carbon layers, and the average plane size may be 0.02 to 20 탆. When the average thickness is 20 carbon layers or more, or when the average plane size is 20 占 퐉 or more, absorption into plants may become difficult. Further, when graphene having an average plane size of 0.02 탆 or less is produced, economical efficiency may be a problem due to an additional process such as a classification process.

In addition, it is also well known that the surface of the graphene can be chemically treated to functionally function as a graphene surface. Examples of such techniques include oxidation of graphene surface using nitric acid and sulfuric acid, reduction of graphene surface through reaction with reducing agent, alkylamidation of graphene surface by reaction with alkylamine, and reaction with alkyl alcohol And the like.

In this invention, graphene may be provided in admixture with the soil before planting. In this case, the concentration of graphene in the graphene mixed soil is preferably adjusted within the range of 0.01 to 100 wt / wt ppm. If the concentration of graphene in the soil is 0.01 wt / wt / ppm or less, the effect of promoting growth by graphene may be insignificant. If the concentration of graphene is 100 wt / wt / wt or more, the economical burden of graphene may increase.

It is also possible to spray an aqueous solution of graphene on the soil after the plant has been planted, or to spray the soil with graphene adsorbed on silicate mineral particles such as talc. In this case, it is preferable to adjust the amount of graphene supplied to the soil of 1 ary (100 square meters) within the range of 0.01 to 100 g based on one application. After one application, it is natural that fertilization can be applied at intervals of 10 ~ 30 days depending on the growth condition of the plant.

Alternatively, if graphene is applied to expensive plants such as rare shrubs or arbors, it may be applied to the soil around the main stem following the root of the individual tree, have. In this case, the amount of graphene to be supplied per 100 parts by weight of the tree is preferably adjusted to 0.001 to 1.0 part by weight based on the weight of the tree. However, the economical burden due to graphene fertilization is relatively small in the case of specially expensive trees, and it is natural that the supply amount of graphene per 100 weight parts of trees can be adjusted to 1.0 weight part or more.

Graphene can also be provided to crops or trees through side-by-side fertilization, diluted in water. In this case, it is preferable to adjust the concentration of the diluted solution of graphene to 0.1 to 1000 weight / volume ppm, and the amount of graphene to be applied based on the area of the soil in which the plant is planted is within the range of 0.01 to 100 g . After one application, it is natural that fertilization can be applied at intervals of 10 ~ 30 days depending on the growth condition of the plant.

In this invention, graphene can contribute as an active ingredient either directly or indirectly to the promotion of plant growth in soil or in two different environments, such as within a plant, as follows.

First, graphene is adsorbed on the soil surface and can contribute to the growth of the plant, which can increase the emission of far-infrared rays from the soil due to graphene, and furthermore, By acting on the nanoparticle effect of graphene in the migration process of nutrients (for example, by allowing organic or inorganic nutrients to be adsorbed on the graphene surface and being easily transferred to the roots) Because.

Second, graphene can contribute to the promotion of plant growth under the environment in which it exists in the plant. For promoting plant growth, fertilized graphene can be absorbed into the plant from roots or sides in a nano-sized dispersion in water. The planar graphene is a three-dimensionally crumbled shape due to the Brownian motion in solution and has an average size in the dynamic equilibrium state, and its three-dimensional average diameter is much smaller than the plane size of the graphene originally, Roots, stems, or leaves. Of course, the smaller the lateral dimension of the provided graphene provided for the fertilization of the soil or plant, the smaller the dynamic three-dimensional size of the three-dimensional particle that it folds out of, It is obvious that the absorption rate and the absorption rate of the water-absorbing agent will increase.

Apart from the action of graphene present in the soil environment, there has been little disclosure until now of the specific functional groups in which graphene present in the plant functions as an active ingredient for promoting plant growth. The present inventors intend to analyze the mechanism of action of graphene as a plant growth promoting active ingredient in various theoretical perspectives as follows.

First, the far infrared effect can be mentioned. Since graphene forms strong absorption bands in the ultraviolet and far-infrared regions, graphenes present in plants, ie, leaves, stems and roots, exhibit vibrational relaxation after ultraviolet absorption and resonant light scattering ) Can increase the energy density of the far-infrared rays in the plant. That is, when the density of far infrared rays is increased by graphene in the plant, it can be expected that it will help the plant growth by increasing the activity of the body fluid and the activity of the enzyme action.

Second, the nanofluid effect of graphene solution and the adsorption effect of graphene. When graphene is dispersed in the body fluid of a plant at a nanoscale size, movement of the water and nutrients through the intercellular movement channels in the water tube, stem or other plant is activated due to the nanofluid effect and the adsorption ability of graphene, Can contribute to the growth of the plant.

Third, the ultraviolet absorption effect of graphene can be cited. Specifically, the compound constituting the chlorophyll of a plant can be deactivated by active oxygen, and graphene in the plant effectively blocks ultraviolet rays, thereby reducing the production of reactive oxygen species generated by ultraviolet rays, thereby lowering the chlorophyll activity And as a result, the photosynthesis of plants can be promoted.

Fourth, in the metabolic process of plants, graphene can contribute through a sort of co-enzymatic role. For example, the electric and electronic behavior of graphene in vivo has not yet been sufficiently studied. However, graphene in a plant is an electron transfer process that is essential for photosynthesis of plant photosynthesis and dark reaction, and cell respiration, or It will not be possible to exclude the possibility of promoting plant growth in a manner involving the proton transfer process.

Finally, it can contribute to promoting the metabolism of symbiotic microorganisms present in and around roots, stems, and leaves of plants through mechanisms of action of biochemical reactions such as far-infrared effect of graphene as described above have. As a direct or indirect result of the active metabolism of microorganisms that are symbiotic with plants, it is estimated that the application of graphene according to the present invention may be another cause of promoting the growth of plants.

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited by these examples.

Preparation Example 1 Preparation of 'graphene aqueous solution 1'

300 g of the graphene powder purchased from Nano Reader Co., Ltd. was placed in 2700 g of purified water, and ultrasonic waves were applied for 6 hours while mechanically stirring to prepare a 'graphene aqueous solution 1' having a solid content of 10.0 wt%.

The graphene aqueous solution 1 was sufficiently diluted with purified water to reach a nano-dispersed state, and a sample was prepared. The sample was analyzed with a transmission electron microscope (TEM) at a resolution of 2 nm, 5 ㎛ range. As a result of analyzing the sample with atomic force microscope (AFM), it was confirmed that the plane thickness of graphene was distributed in the range of 3 to 15 atom layers.

Preparation Example 2 Preparation of 'graphene aqueous solution 2'

200 g of the graphene aqueous solution 1 obtained in Preparation Example 1 was put into a ball mill together with zirconia beads having a size of about 10 탆 and the ball mill was operated for 24 hours and filtered to obtain graphene having a solid content of 10.0% Aqueous solution 2 'was prepared.

After diluting the graphene aqueous solution 2 to a nano-dispersed state, a measurement sample was prepared and analyzed by a high-resolution transmission electron microscope (HRTEM) having a resolution of 0.1 nm. As a result, a unique diffraction I was able to get an image that showed a pattern. Separately, the sample was analyzed with a transmission electron microscope (TEM) at a resolution of 2 nm, and it was confirmed that the plane size of graphene was distributed in the range of 20 to 500 nm. As a result of analyzing the sample with an atomic force microscope (AFM), it was confirmed that the plane thickness of graphene was distributed in the range of 1 to 5 atom layers.

Preparation Example 3: Preparation of 'graphene-adsorbed talc powder'

80 g of the graphene solution 2 obtained in Preparation Example 2 was taken and put into a high-speed mixer together with 2 kg of talc powder having an average particle size of about 10 탆, and the mixer was operated for 10 minutes. The resulting mixture was spread on a wide tray, After drying for one day, the mixture was pulverized in a barrel so that a graphene-adsorbed talc powder was prepared. The content of graphene in the 'graphene adsorbed talc powder' composition is 0.4% by weight.

Example 1: Application of 'graphene aqueous solution 1' to ginseng field

The 'graphene solution 1' was diluted with agricultural water and sprayed on a 6-year-old cane field with a graphene content of 20 weight / volume ppm in a side-seeded manner. (Gangwon-do, Hongcheon, May 15, 2017) With respect to the amount of grapefruit, the area of the goat's field was 1 gallon of the diluted solution, 20 liters of which was used. Respectively.

As a second fertilization, about 30 days after the first fertilization, a dilute solution of 'graphene solution 1' was sprayed on the farm in the same way (fertilization on June 16).

As a third fertilization, after about 25 days after the second fertilization, a dilute solution of 'graphene solution 1' was sprayed on the farm in the same way (fertilization on July 10).

Example 2: Application of 'graphene aqueous solution 2' to ginseng field

In the same manner as in Example 1, 'graphene aqueous solution 2' was fertilized in a canola field. Agricultural land area 1 The amount of grains used per grain was the same as in Example 1. All the fertilization of the first to third treatments were carried out on the same date as in Example 1.

Example 3: Fertilization of 'graphene-adsorbed talc powder' in a field of goat ginseng

The 6-year-old ginseng field that grew on the leaves sprinkled evenly the 'talc powder adsorbed on graphene'. (Fertilization date of May 15) Area of goat farms 1 kg of talc powder (graphene content 0.4 wt%) was used, and the amount of graphene used per grain area was 4 g.

Comparative Example 1: Control experiment for Examples 1 and 2

As a control experiment on the fertilization of the graphene aqueous solution, agricultural water not containing graphene was sprinkled in an amount of 20 liters per 1 area of the arbor in the same amount of surrounding soils. For accurate comparison, 20 liters of the agricultural water was sprayed on each of the first, second and third sides on the same day as in Examples 1 and 2.

Comparative Example 2: Control experiment for Example 3

As a control experiment for Example 3, a talc powder in which graphene was not adsorbed was sprayed on the surrounding soil of the same conditions under the same conditions.

Analysis of the results of graphene fertilization on goat gardens

1. Analysis of short-term effects of graphene fertilization

With respect to the first fertilization of Examples 1 to 3 and Comparative Examples 1 and 2 conducted on May 15, changes in the state of the leaves of goat's ginseng over time were visually evaluated.

The colors of the goat ginseng leaves of the agricultural land which were the objects of Examples 1 to 3 and Comparative Examples 1 and 2 were all pale green before the fertilization and about 20% of the leaves were yellow.

The state of goat ginseng leaves at 1 day after fertilization was as follows. During this period, rain did not come down and normal irrigation for the cultivation of goats was maintained.

(1) Example 1: The number of yellow leaves was reduced to about 10%, and about 50% of the leaves changed to green.

(2) Example 2: Almost no yellow leaves were observed, and about 80% of the leaves changed color to green.

(3) Example 3: The number of yellow leaves was reduced to about 10%, and about 50% of the leaves changed to green.

(4) Comparative Examples 1 and 2: The color of the leaves was almost the same as that before fertilization.

The state of goat ginseng leaves at 5 days after fertilization was as follows. During this period, rain did not come down and normal irrigation for the cultivation of goats was maintained.

(1) Example 1: The number of yellow leaves decreased to less than 5%, and about 70% of the leaves changed to green.

(2) Example 2: Yellow leaves were almost invisible, and about 90% of leaves changed color to green or dark green.

(3) Example 3: Yellow leaves were almost invisible, and about 90% of the leaves turned green.

(4) Comparative Examples 1 and 2: The color of the leaves was almost the same as that before fertilization.

From the above results, it was found that the effect of the seedling ginseng on the growth of the goat ginseng was evident through the change of the color of the goat ginseng leaf. In addition, when Example 1 and Example 2 were compared, it was found that as the average thickness and the average plane size of the graphene were decreased, the effect of fertilization appeared faster and the effect was also excellent.

In addition, a comparison between Example 2 and Example 3 shows that although the amount of graphene used in Example 3 is 10 times that of Example 2, the effects after 1 day and 5 days after fertilization are all rather low , And that the absorption of graphene into the plant through the leaf surface was superior to the absorption of graphene through the soil.

2. Analysis of long-term effects of graphene fertilization

Three applications according to Examples 1 and 2 and Comparative Example 1 conducted on May 12, June 16, and July 10, and Example 3 and Comparative Example conducted on May 12 With regard to one fertilization of 2, the timing of the leaves of goat's ginseng was visually evaluated.

The evaluation of the timing of the leaves of the goat ginsengs in the agricultural fields subject to the examples 1 to 3 and the comparative examples 1 and 2 was carried out on July 12, July 21, July 31, August 10, It was done by the naked eye on August 22. Table 1 shows the number of leaves that still remain in a green state on each date among all the goat ginseng leaves based on when the leaves were the most active, by each farmland.

<Percentage of goat germ leaves remaining in green leaves> Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 July 11 90% 100% 100% 80% 80% July 21 80% 90% 80% 40% 50% July 31 60% 80% 70% 20% 20% August 10 30% 50% 40% 5% 10% August 22 10% 30% 20% 0% 5%

Based on the data in Table 1, it is estimated that the percentage of leaves remaining in blue leaves among the goat ginseng leaves is 30%.

Example 3 (Aug. 16), Comparative Example 1 (Jul. 31), Comparative Example 2 (Jul. 31), Example 2 (Aug. 22), Example 3 (Aug. Based on these data, fertilization of graphene yielded a number of days of delaying the leaf-cutting time of goat's ginseng; Example 1 (extended 10 days), Example 2 (extended 22 days), Example 3 (extended 16 days).

This long-term result shows almost the same pattern as the analysis of the short-term effect according to the graphene fertilization derived from the visual observation of the color of the above-mentioned goat ginseng leaf.

Figs. 1 and 2 are photographs taken on Aug. 24 of the goat farm in Example 2 and the goat farm in Comparative Example 1, respectively. In the farmland of Example 2, , It can be confirmed that the goat ginseng leaves have been completely removed.

Example 4: Application of 'graphene aqueous solution 2' to implanted bamboo

The present inventors tested the promoting effect of grapnin on plant growth of two bamboo trees planted in a park located in Suwon City. These bamboos are each about 10 meters in length, and survived without suffering among the ten bamboo trees transplanted in June 2016. The two bamboo trees that began to grow in the middle of April, 2017, had already begun to bloom in early July with poor growth of the leaves.

The inventor diluted the graphene aqueous solution 2 prepared in Example 2 into agricultural water to prepare a solution having a graphene concentration of 1 wt / vol%, and applied only to one of the above two grains, (July 5, 2017). On the basis of the weight of solids, the amount of graphene grafted to the bamboo was 20 g. With subsequent passage of time, the number of bamboo leaves remaining as green leaves on the stems extending from the large stems was visually analyzed and recorded as a percentage of the total number of bamboo leaves before starting to bloom (Table 2 ).

<Percentage of bamboo leaves remaining in green leaves> Bamboo with graphene Unclaimed bamboo July 5 90% 95% July 18 90% 80% August 1 90% 50% August 12 90% 20% August 23 80% Less than 5%

As shown in Table 2, bamboo that did not have graphene foliage continued to be leafed due to heavy rain and wind during the experiment, and most of the leaves were lost after 44 days. However, graphene- , It can be seen that most of the leaves, which are located at 2 to 10 meters above the ground, remain on the stem with green leaves, except for some leaves that have fallen by strong winds. The graphene remaining in the soil will have little effect on the growth of the bamboo leaves above 2 m above the ground. The results of Example 4 show that graphene, which has a positive effect on bamboo growth, Suggesting that there is a unique action.

Graphene grafted in the soil was absorbed into the bamboo body through the roots. Graphene, which is present in the bamboo plant in this way, has a far infrared ray emission, promotion of movement of nutrients, prevention of chlorophyll degradation, function as coenzyme, It is interpreted as promoting the growth of bamboo before the action of microorganisms.

Claims (2)

A composition comprising graphene as an active ingredient for promoting plant growth.
The composition according to claim 1, wherein the graphene has an average thickness of 1 to 20 atomic layers and an average plane size of 0.02 to 20 탆. The composition contains graphene as an active ingredient for promoting plant growth.

Images