Plant growth promoting components

Abstract

To provide a plant growth promoting composition that can promote plant growth more safely and inexpensively compared to conventional materials. [Solution] A plant growth promoting composition containing one or more selected from the group consisting of onion extract and onion powder as an active ingredient.

Description

Technical Field

[0005] ,

[0001] The present invention relates to a plant growth promoting composition and a plant growth promoting method.

Background Art

[0002] Currently, due to the explosive increase in population, producing sufficient amounts of food plants has become a global issue. In addition, problems such as desertification of land due to the reduction of green spaces, and the rise in surface temperature based on the global warming phenomenon have also emerged, and the environmental problems in growing plants are increasing. That is, excessive stress based on global environmental factors in plants often becomes a problem in plant growth.

[0003] Therefore, there is a demand for a technology that promises more efficient harvesting. Biostimulants are attracting attention as a new technology that reduces damage to plants caused by climate and soil conditions by controlling environmental stress on plants and provides healthy plants.

[0004] Patent Document 1 discloses a plant stomatal opening promoter containing stevia, and it has been reported that artificial promotion of the opening of plant stomata by stevia improves heat stress tolerance. Patent Document 2 discloses a composition for activating genes that activate the ethylene and / or jasmonic acid signal transduction system, containing yeast cell wall degradation products. It has been reported that by applying yeast cell wall degradation products to plants, the expression of plant defensin genes involved in the antibacterial properties and disease prevention of plants is activated. Patent Document 3 discloses a method for increasing the yield of cereals by inoculating plant bodies for cultivating cereals with cell wall components of methanol-assimilating bacteria.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Patent No. 6741262 [Patent Document 2] Patent No. 4931388 [Patent Document 3] Japanese Patent Publication No. 2019-180361 [Overview of the project] [Problems that the invention aims to solve]

[0006] As mentioned above, various studies have been conducted to date using different materials to improve plant tolerance to environmental stress and increase yield, but there have been no reports of studies using onion extract or onion powder. [Means for solving the problem]

[0007] As a result of diligent research, the inventors discovered, using a uniquely developed high-precision screening method, that one or more materials selected from the group consisting of onion extract and onion powder can be effective ingredients for promoting plant growth, thus completing the present invention.

[0008] In other words, the present invention is as follows. [1] A plant growth promoting composition comprising one or more substances selected from the group consisting of onion extract and onion powder as an active ingredient. [2] A plant growth promoting composition as described in [1] above, which has a phosphorus absorption promoting effect. [3] The plant growth promoting composition described in [2] above, which increases the expression level of phosphate absorption-related genes. [4] The plant growth promoting composition according to [2] above, further having an effect of improving stress tolerance to one or more stresses selected from the group consisting of chemical stress, including nutrient deficiency stress or nutrient excess stress, pH stress, and salt stress. [5] The plant growth promoting composition described in [4] above, which increases the expression level of stress tolerance genes to one or more stresses selected from the group consisting of chemical stress, including nutrient deficiency stress or nutrient excess stress, pH stress, and salt stress. [6] A plant growth promoting composition according to any one of the above [1] to [5], having one or more plant growth promoting effects selected from the group consisting of elongation or increase in weight of stems, leaves or roots, increase in the number of leaves, promotion of flowering or fruiting, increase in the number of flowers or fruits, increase in plant weight or crop yield, greening, and promotion of tillering. [7] A method for promoting plant growth, comprising using a plant growth promoting composition containing one or more selected from the group consisting of onion extract and onion powder as an active ingredient, on a plant, or on the soil or culture medium in which the plant grows. [8] The plant growth promoting method according to [7] above, wherein the amount of the plant growth promoting composition used in the culture medium or diluent is 0.001 to 50% by mass or 0.001 to 50% by volume. [Effects of the Invention]

[0009] By applying a composition containing one or more selected from the group consisting of onion extract and onion powder of the present invention to plants, plant growth can be promoted more safely and inexpensively compared to conventional materials. [Brief explanation of the drawing]

[0010] [Figure 1] These images show the improvement in root development of rice plants when no onion extract was added (left) and when 0.45 mL of a plant growth promoting composition containing onion extract was added (right) (Example 1). [Figure 2] These images show the improvement in root development of rice plants when no onion extract was added (left) and when 0.90 mL of a plant growth promoting composition containing onion extract was added (right) (Example 1). [Figure 3]The results of measuring the dry weight of rice roots when no onion extract was added and when 0.45 mL or 0.90 mL of a plant growth promoting composition containing onion extract was added are shown (Example 1). [Figure 4] The total amount of phosphorus contained in the roots of rice when no onion extract was added and when 0.45 mL or 0.90 mL of a plant growth promoting composition containing onion extract was added is shown (Example 2). [Figure 5] This is an image observing the improvement of rice root growth when no onion powder was added (left) and when 0.45 g of a plant growth promoting composition containing onion powder was added (right) (Example 3). [Figure 6] This is an image observing the improvement of rice root growth when no onion powder was added (left) and when 0.90 g of a plant growth promoting composition containing onion powder was added (right) (Example 3). [Figure 7] The results of measuring the dry weight of rice roots when no onion powder was added and when 0.45 g or 0.90 g of a plant growth promoting composition containing onion powder was added are shown (Example 3). [Figure 8] The total amount of phosphorus contained in the roots of rice when no onion powder was added and when 0.45 g or 0.90 g of a plant growth promoting composition containing onion powder was added is shown (Example 4). [Figure 9] The expression level of phosphate absorption related genes in the roots of rice when no onion extract was added and when 0.90 mL of a plant growth promoting composition containing onion extract was added is shown (Example 5).

Mode for Carrying Out the Invention

[0011] Hereinafter, the mode for carrying out the present invention (hereinafter, also referred to as "the present embodiment") will be described in detail. The present invention is not limited to the present embodiment, and can be variously modified and implemented within the scope of the gist thereof.

[0012] <Plant Growth Promoting Composition> The plant growth promoting composition in this embodiment contains one or more active ingredients selected from the group consisting of onion extract and onion powder. The plant growth promoting composition in this embodiment may contain one or two active ingredients selected from the group consisting of onion extract and onion powder; that is, it may contain only onion extract or onion powder as an active ingredient, or it may contain both onion extract and onion powder as active ingredients. Onions are plants of the genus Allium in the family Amaryllidaceae. Specifically, Allium cepa is an example. There are no particular restrictions on onion varieties, and examples include yellow onions, white onions, purple onions (red onions), salad onions, pearl onions, ruby ​​onions, leaf onions, and shallots. More specifically, Kitawase No. 3, SN-1, SN-3, SN-3A, Okhotsk 222, Okhotsk No. 1, Okhotsk 333, Kitamomiji 2000, Super Kitamomiji, H235, and Kitaha Yate No. 2, Bullet Bear, Arrow Bear, Power Wolf, Brown Bear, Kodiak, Ikor, Vegas, Hayajiro, Sarari, Karoe One, Ezomaru, Sarasa Gold, Kurenai, R-5, Red Eye Early, Red Eye II, Red Eye, Red One, Yukigeshiki 2, Yukigeshiki, White No. 1, Kita Hayase No. 1, Pecoros 22 Super, Pecoros F Okhotsk, Kitami Yellow, Sapporo Yellow, Sorachi Yellow, Quer Gold, OPP-5 OMP-3, OSP-3, CS3-12, Toyohira, Idol Momoe, Idol Masako, Idol Junko, Keeper 808, Keltama Ruby, Hero Z, Polestar 100, Shōjō Aka, Risshun no Kaori, Hokkai Tenshin, Kita no Rouge, Hōsan Kogane, Hōsan Kurenai, Hidaten, Hidamari, Bansei Kogane, Hakata Kogane EX, Hakata Kogane, Tokyo Red, Tenju Tamanegi, Chūzōyō Tsuritama, Chūsei Kogane, Chikyu Super Up, Chikyu A Up No. 2, Chikyu Up No. 1, Daihikyu, Wase Taka, Wase Maru Hidetama E-type, Wase Maru Hidetama, Wase Kogane, Senshu Nakataka Yellow, Senshu Nakataka, Aka Tama Salad, Shin Bansei Kogane, Shonan Red, Harukaze Maru, Haru Ichiban, Hidetama Maru, Takano Marugata Tamagi, Takano Ogon Tamagi, Beni Hidetama Maru, Kotaka Aka, Kotaka Rouge, Tsukiwa No. 2, Kei, Kinsho Senshu Ki No. 2 Tamagi, Kinsho Shunyo Ki Tamagi, Kinsho Tama no Haru Tamagi, Nishikimari, Kikin, Kairyo Unzen Maru, Oshu, Unzen Chogokuwase, Rose Tama, Red Relief,Roubaix, Levain, Lambda No. 2, Lambda Yellow, Lucky, Momiji No. 3, Marumi, Mach, Mercury No. 3, White Bear, Bolt, Hold, Fresh Red, Power, Happy 501, Hyper Linear (Test MO-75), Neo Earth, Top Gold 525, Top Gold 515, Top Gold 430, Top Gold 415, Top Gold 305, Turbo, Tarzan, Sonic, Century No. 2, Swallow, Spurt, Super Haru Ichiban, Super Linear, Super Moon, Super Kogane, Charm, Shinonome, Jet Bow Examples of onion varieties include Ru, Jetstar, Salad Red, Sakura Express II, Sakura Express I, Kohaku No. 2, Kohaku, Keltama, Kurenai, Aurora, A-One, Yellow Drop, Amagashi No. 2, Aton, Early Top, O·P Yellow, O·L Yellow, O·K Yellow, MT-1411, F1 Early-Grown Onion, F1 Extra Early-Grown FA Onion, F1 Kyoto-Grown Onion, AS-115, Kazusa No. 13, Tiger Jet, KA953, KAR-003, KA-957, KA-956, TPS-157, Risshun no Kaori, TG-320, Hama no Takara, Hamasho, and Noncooler. The origin of the onions is not particularly limited.

[0013] In this embodiment, onion extract is obtained by extracting specific components from onions, and the parts used for extraction are not particularly limited. Examples include leaf blades, leaf sheaths (petioles), bulbs (scale leaves, storage leaves, edible parts), peels (protective leaves), cores, stems (flower stalks, flower bulb peduncles), and roots, which may be used individually or in combination. Onion extract can be obtained, for example, by the method described in <Method for preparing plant growth promoting composition> below. Onion powder is obtained by drying and grinding onions or onion extract, and is not particularly limited.

[0014] The plant growth promoting composition in this embodiment is a composition having a plant growth promoting effect, where the plant growth promoting effect includes, for example, growth promoting effects such as elongation or increase in weight of stems, leaves, or roots, increase in the number of leaves, promotion of flowering or fruiting, increase in the number of flowers or fruits, increase in plant weight or crop yield, greening, or promotion of tillering.

[0015] More specifically, the observation of a plant growth-promoting effect means that the percentage increase in actual weight or dry weight increases when comparing the use of the plant growth-promoting composition of this embodiment with the case where it is not used. The actual weight or dry weight may be the actual weight or dry weight of the entire plant, or it may be the actual weight or dry weight of each part of the plant (preferably the roots). When the plant growth-promoting composition is used, the percentage increase in actual weight or dry weight should preferably increase by 10% or more, more preferably 20%, and even more preferably 30% or more compared to the case where the plant growth-promoting composition of this embodiment is not used. The observation of a plant growth-promoting effect includes cases where, in cases where no growth is observed at all without the use of the plant growth-promoting composition, growth becomes observed with the use of the plant growth-promoting composition. Note that the above values ​​are average values ​​for the entire plant to which the plant growth-promoting composition was applied.

[0016] In addition, the plant growth-promoting effect also includes the following effects that improve plant activity: 1) Improved root elongation and root survival rate 2) Increased nutrient absorption efficiency 3) Induction of flower buds, promotion of flowering, and increase of fruit set. 4) Accumulation of components such as sugars 5) Increased water-saving effect 6) Inducing effect of callus formation 7) Improvement of plant size, particularly elongation or thickening of above-ground and underground parts. 8) Wound repair In other words, the plant growth-promoting composition of this embodiment may have growth-promoting effects such as elongation of stems and leaves or roots, increase in the number of leaves, promotion of flowering or fruiting, increase in the number of flowers or fruits, increase in plant weight or crop yield, greening, or promotion of tillering, in addition to the effects described in 1) to 8) above. The effect described in 1) above may promote nutrient absorption by the roots, thereby promoting the growth of the entire plant.

[0017] The plant growth promoting composition in this embodiment may have a phosphate absorption promoting effect. In this embodiment, "phosphate absorption promoting" means promoting the absorption of phosphate by plants, preferably by the roots of plants. By promoting the absorption of phosphate by plants, the amount of phosphate present in the plant body may increase. Furthermore, the phosphate whose absorption is promoted may be phosphate in the soil or culture solution in which the plant grows, or phosphate in fertilizer applied to the soil or culture solution. The plant growth promoting composition in this embodiment may activate phosphate absorption-related molecules, thereby promoting phosphate absorption by plants. As one embodiment, this embodiment also provides a phosphate absorption promoting composition containing one or more selected from the group consisting of onion extract and onion powder as active ingredients.

[0018] The plant growth promoting composition in this embodiment may exhibit a plant growth promoting effect by having a phosphorus absorption promoting effect.

[0019] The phosphorus absorption-promoting effect of the plant growth-promoting composition in this embodiment can be confirmed, for example, by growing a plant to which the plant growth-promoting composition has been applied under conditions of suitable growth temperature and growth period for the plant, and comparing the amount of phosphorus in the plant (preferably in the roots) with the amount of phosphorus in a plant not to which the plant growth-promoting composition has been applied, and evaluating the result.

[0020] If the plant growth-promoting composition in this embodiment has a phosphorus absorption-promoting effect, it may further have an effect of conferring tolerance to environmental stresses such as chemical stress, pH stress, and salt stress. Chemical stress includes, for example, nutrient deficiency stress and nutrient excess stress.

[0021] In this embodiment, "environmental stress" tolerance refers to the ability to grow normally or in a near-normal state even under growth conditions that subject to environmental stress, without substantially suffering undesirable effects such as inability to grow (death), poor growth (e.g., whitening or yellowing of the plant body, reduction in root length or number of leaves), reduced growth rate, or reduction in plant weight or crop yield. By improving the environmental stress tolerance of plants with the plant growth promoting composition of this embodiment, plants can grow normally even in external environments that would normally have undesirable effects on plant growth.

[0022] The plant growth promoting composition in this embodiment may have a phosphorus absorption promoting effect, as well as an effect of improving stress tolerance to one or more stresses selected from the group consisting of chemical stress, including nutrient deficiency stress or nutrient excess stress, pH stress, and salt stress.

[0023] In this embodiment, the environmental stress tolerance of a plant can be confirmed by growing the target plant under various environmental stress conditions and evaluating its phenotype. For example, the presence or absence of salt stress tolerance can be confirmed by growing the target plant in a culture medium or soil to which salt has been added at an appropriate concentration, under conditions of optimal growth temperature and growth period for the plant, and evaluating its phenotype.

[0024] If the plant growth-promoting composition in this embodiment has a phosphate absorption-promoting effect, it may increase the expression level of phosphate absorption-related genes. The phosphate absorption-related genes are not particularly limited and include generally known genes that are thought to be related to phosphate absorption, such as genes disclosed in public databases such as the National Center for Biotechnology Information (NCBI), Ensembl Plants, The Arabidopsis Information Resource (TAIR), and The Rice Annotation Project (RAP).

[0025] If the plant growth-promoting composition in this embodiment has an effect of improving environmental stress tolerance, it may activate genes in the stress response system. The genes in the stress response system are not particularly limited and include genes that are generally known as response indicators to chemical stress, pH stress, and salt stress. Genes that are generally known as response indicators to chemical stress may also be genes that are generally known as response indicators to nutrient deficiency stress and nutrient excess stress. Genes that are generally known as response indicators to chemical stress, pH stress, and salt stress are, for example, genes disclosed in known databases such as the National Center for Biotechnology Information (NCBI), Ensembl Plants, The Arabidopsis Information Resource (TAIR), and The Rice Annotation Project (RAP).

[0026] The plant growth promoting composition in this embodiment may contain one or more selected from the group consisting of onion extract and onion powder, either alone or in combination with one or more agriculturally acceptable components. Agriculturally acceptable components are not particularly limited, but examples include solvents, carriers, excipients, binders, solubilizers, stabilizers, thickeners, leavening agents, lubricants, surfactants, oily liquids, buffers, bactericides, antifreezes, defoamers, colorants, antioxidants, preservatives, and further active ingredients. Agriculturally acceptable carriers include agriculturally acceptable liquid carriers such as water, mineral oil fractions like kerosene or diesel oil, plant or animal-derived oils, cyclic or aromatic hydrocarbons (e.g., paraffin, tetrahydronaphthalene, alkylated naphthalenes or their derivatives, or alkylated benzenes or their derivatives), alcohols (e.g., methanol, ethanol, propanol, butanol, or cyclohexanol), ketones (e.g., cyclohexanone), or amines (e.g., N-methylpyrrolidone), or mixtures thereof.

[0027] If the plant growth promoting composition in this embodiment contains one or more additional active ingredients, various compounds known in the art that have phosphate absorption promoting effects and environmental stress tolerance improving effects can be applied as the additional active ingredients. The inclusion of such one or more additional active ingredients in the plant growth promoting composition tends to further improve the phosphate absorption promoting effect and environmental stress tolerance of plants.

[0028] The plant growth promoting composition in this embodiment can be used in combination with conventionally known agricultural materials such as pesticides and fertilizers. Examples of agricultural materials include pesticides, fertilizers, soil conditioners, and growing media (potting soil). Specifically, pesticides may include fungicides, insecticides, insecticide-fungicides, acaricides, nematicides, rodenticides, insecticides / repellents, attractants, spreading agents, hormones (growth regulators), herbicides, etc. Fertilizers may include organic fertilizers, chemical fertilizers, liquid fertilizers, solid fertilizers, compound fertilizers, compost, growth promoters, vitality boosters, calcium supplements, etc. Soil conditioners may be intended for physical, chemical, or biological soil improvement, and may also include oxygen supply agents, etc. Furthermore, pesticides, fertilizers, soil conditioners, and growing media may contain components derived from plants, animals, lime, minerals, or microorganisms.

[0029] In a plant growth promoting composition, the content of one or more substances selected from the group consisting of onion extract and onion powder relative to the entire plant growth promoting composition may be any value as long as one or more substances selected from the group consisting of onion extract and onion powder function as an active ingredient for promoting plant growth. For example, it may be 5, 10, 20, 30, 40, 50, 60, 70, 80, or 90% by mass (volume) or more, and 99, 95, 90, 80, 70, 60, 50, 40, 30, 20, or 10% by mass (volume) or less.

[0030] The plant growth promoting composition in this embodiment can be used as an agricultural chemical agent or pesticide to promote plant growth. The plant growth promoting composition may be in any form, such as a solid (e.g., powder or granules) or a liquid (e.g., solution or suspension), and is preferably used in the form of a liquid such as a solution or suspension. When used as a solution, it may be in liquid form, or it may be used as a liquid prepared at the time of application.

[0031] The dosage form of the plant growth promoting composition of this embodiment is not particularly limited and can be formulated in dosage forms commonly used in the art, such as emulsions, wettable powders, liquids, aqueous solutions, powders, pastes, or granules.

[0032] In this embodiment, the plants to which the plant growth promoting composition can be applied are not particularly limited, and examples include angiosperms and gymnosperms. Examples of target plants include Asteraceae plants such as chrysanthemums and gerberas, Solanaceae plants such as potatoes, tomatoes and eggplants, Brassicaceae plants such as rapeseed and rapeseed, Poaceae plants such as rice, maize, wheat, sugarcane and barley, Fabaceae plants such as soybeans, Apiaceae plants such as carrots, Lamiaceae plants such as basil, mint and rosemary, Convolvulaceae plants such as morning glories, Salicaceae plants such as poplars, and Euphorbiaceae plants such as castor bean, cassava and jatropha. Examples include plants of the Convolvulaceae family such as sweet potatoes, plants of the Rutaceae family such as oranges and lemons, plants of the Rosaceae family such as cherry blossoms and roses, plants of the Orchidaceae family such as phalaenopsis orchids, plants of the Gentianaceae family such as lisianthus, plants of the Primulaceae family such as cyclamen, plants of the Violaceae family such as pansies, plants of the Liliaceae family such as lilies, plants of the Amaranthaceae family such as sugar beets, plants of the Vitaceae family such as grapes, plants of the Cupressaceae family such as cedar and cypress, plants of the Oleaceae family such as olives and osmanthus, and plants of the Pinaceae family such as Japanese red pine.

[0033] The plants targeted may include not only the whole plant (i.e., a complete plant), but also plant tissues or organs (for example, cut flowers, or vegetative reproductive organs such as rhizomes, tubers, corms, or runners), cultured cells, and / or parts of the plant such as callus.

[0034] The plant growth promoting composition in this embodiment can be applied to the whole or a part of a plant at any growth stage, including before or after germination (for example, a seed, seedling, or the whole or a part of a mature plant).

[0035] <Method for preparing a plant growth promoting composition> As a method for preparing a plant growth promoting composition, for example, one or more components selected from the group consisting of onion extract and onion powder can be obtained, and then mixed with the above-mentioned agriculturally acceptable components as needed. The method for obtaining onion extract is not particularly limited, and general methods for extracting plant extracts can be used. Specifically, for example, it can be obtained by a method that includes the steps of: obtaining raw onion extract material by heating or crushing one or more selected from the group consisting of onion leaf blades, leaf sheaths (petioles), bulbs (scale leaves, storage leaves, edible parts), peels (protective leaves), cores, stems (flower stalks / flower bulb peduncles), and roots, and then removing impurities; concentrating the raw onion extract material obtained in the first step to obtain an onion concentrate; and fractionating the onion concentrate obtained in the first step to obtain an onion extract containing specific components. Alternatively, the raw onion extract material or onion concentrate may be used as is as onion extract. At each step, or after each step, the raw onion extract material, onion concentrate, or onion extract may be heated or pressurized. When performing the heat treatment or pressurization treatment, a solvent may be added as appropriate. Furthermore, the conditions for obtaining onion extract can be appropriately determined depending on the variety, part, and condition of the onion used. The method for obtaining onion powder is not particularly limited. It can be obtained by drying fresh or frozen onion products such as onion extract raw materials, onion concentrate, or onion residue such as impurities generated when obtaining onion extract, or onion extract raw materials, onion concentrate, onion extract, or onion (one or more selected from the group consisting of onion leaf blades, leaf sheaths (petioles), bulbs (scale leaves, storage leaves, edible parts), peels (protective leaves), cores, stems (flower stalks / flower bulb peduncles), and roots) using methods such as hot air drying, air drying, dry heat drying, or reduced pressure drying, and then crushing them into a powder.

[0036] (Crushing process) Onions can be crushed using fresh or dried onions, for example, by using a blender. When crushing onions, an appropriate amount of water may be added to facilitate processing with a blender or other device. The crushed onions are filtered using a filter cloth or filter paper to obtain onion extract raw material from which impurities have been removed. When filtration, an extraction solvent such as an organic solvent may be added beforehand. Alternatively, impurities may be removed by obtaining the supernatant using a centrifuge instead of filtration.

[0037] (concentration process) The obtained onion extract raw material can be concentrated to obtain an onion concentrate using methods such as vacuum concentration, freeze concentration, or membrane concentration. The concentration ratio is preferably 3 to 30 times, and more preferably 4 to 20 times. When the concentration ratio is 5 times or more, the amount of plant growth promoting composition added to the plant is reduced, which improves handling and tends to reduce transportation costs. When the concentration ratio is 30 times or less, there is less precipitate in the plant growth promoting composition, which tends to make it easier to handle. Furthermore, in the preparation of the plant growth promoting composition, concentration of the onion extract raw material is not essential, and the obtained onion extract raw material may be subjected directly to the following fractionation steps.

[0038] (Fractional process) The obtained onion concentrate can be fractionated by solvent extraction or other methods to obtain onion extract containing specific components. In the fractionation process, for example, hydrophilic and hydrophobic fractions can be obtained by liquid-liquid partitioning. Further purification can be obtained by passing the fraction through a column.

[0039] The onion extract obtained in the fractionation process may be further purified or separated into high-activity fractions as needed. Purification methods include, for example, filtration and adsorption (ion exchange resin column, activated carbon column, etc.). Separation methods for high-activity fractions include gel filtration, adsorption, silica gel column chromatography, and HPLC.

[0040] <Plant growth promotion method> The plant growth promotion method in this embodiment is a method of promoting plant growth by using a composition containing one or more selected from the group consisting of onion extract and onion powder as an active ingredient on a plant, or on the soil or culture solution in which the plant grows. In this method, the plant growth promotion composition can be applied to a plant or a part thereof (e.g., a seed, seedling, or mature plant) at any growth stage, including before or after germination. Furthermore, it can be applied not only to the plant itself, but also to the soil, culture medium, or culture solution in which the plant grows. By applying the plant growth promotion composition to a plant in a growth stage or to the soil, culture medium, or culture solution in which the plant grows, plant growth can be promoted.

[0041] The absorption of phosphorus by plants can also be promoted by using a composition containing one or more selected from the group consisting of onion extract and onion powder as an active ingredient in plants, the soil in which the plants grow, or the culture solution. This embodiment also provides a method for promoting the absorption of phosphorus by plants.

[0042] The plant growth promoting composition may be applied to plants once or multiple times. Similarly, if there are multiple application periods, the number of applications at each period may also be once or multiple times.

[0043] Methods for applying the plant growth-promoting composition to plants include, for example, addition, spraying, coating, and immersion. These methods may be used individually or in combination of two or more. The application of the plant growth-promoting composition to plants may be done manually or using machinery. When using machinery, there are no particular limitations, but for example, application (spraying) may be done using a drone.

[0044] The amount of plant growth promoting composition to be applied to plants is preferably 0.001 to 50% by mass or 0.001 to 50% by volume, more preferably 0.01 to 30% by mass or 0.01 to 30% by volume, and even more preferably 0.01 to 10% by mass or 0.01 to 10% by volume, when applied to the culture solution in which the plants are growing, or when diluted with a diluent and applied to the field or other area where the plants are growing. While sufficient plant growth promoting effects tend to be obtained when the amount of plant growth promoting composition is within the above range, the amount used may be appropriately adjusted depending on the content of one or more selected from the group consisting of onion extract and onion powder in the plant growth promoting composition, the type and growth stage of the plant to which the plant growth promoting composition is applied, and the plant growth environment such as temperature, humidity, and light. The amount used may also be determined by investigating the concentration range in which the effect is obtained using known cultivation test methods. When applying a plant growth-promoting composition diluted with a diluting solvent to plants using a drone, the amount of solution that can be carried on the drone is limited by the drone's payload capacity, etc. Therefore, the amount of plant growth-promoting composition used relative to the diluting solvent is preferably 1 to 50% by mass or 1 to 50% by volume.

[0045] The components of the culture solution and diluent described above are not particularly limited as long as they do not adversely affect plant growth, and may include water, pesticides, etc.

[0046] The above usage amounts will vary depending on the concentration ratio of the onion extract raw material mentioned above, but the above usage amounts represent the preferred range when the concentration ratio is between 3 and 30 times. [Examples]

[0047] The present invention will be described in more detail using examples and comparative examples, but the present invention is not limited in any way by these examples.

[0048] (Method for measuring root weight) The roots were identified based on the color and shape of the rice plants, and their weight was measured in a bottle using a microbalance.

[0049] (Preparation of onion extract) Onion extract raw material was obtained from 100g of onion bulbs cut at 1-10mm intervals, and then the onion extract obtained by concentrating the raw material by approximately 5 times was used in Examples 1-3.

[0050] [Example 1] We evaluated whether onion extract increases root weight, which is important for fertilizer absorption, using rice plants.

[0051] (seedling raising period) Rice seedlings germinated by soaking in distilled water were transferred to hydroponic solutions at the concentrations shown in Table 1 for the seedling stage. The seedlings were then transferred to an artificial climate chamber, where they were grown while the hydroponic solution was changed. (Exam period) Three experimental plots were designed: one plot containing 900 mL of hydroponic solution at the concentrations shown in Table 1, into which the rice plants grown as described above were transferred; another plot containing 0.45 mL or 0.9 mL of onion extract to achieve a final concentration of 0.05 vol% or 0.1 vol%; and a control plot without onion extract. After cultivating the three plots in an artificial climate chamber, the rice plants were removed, dried, and the roots were harvested and weighed. As a result, the plot with 0.05 vol% onion extract showed a 29.1% weight increase compared to the control plot (Figures 1 and 3). Furthermore, the plot with 0.1 vol% onion extract showed a 38.5% weight increase compared to the control plot (Figures 2 and 3). These results indicate that onion extract has the effect of increasing root weight.

[0052] [Table 1]

[0053] [Example 2] The effect of adding onion extract on phosphate absorption was also evaluated using the rice from Example 1.

[0054] (Pretreatment for phosphate determination) In Example 1, the dried rice roots were transferred one by one into tubes. 5 mL of sulfuric acid and 1 mL of hydrogen peroxide were added to decompose the roots. After reacting overnight, 3 mL of the decomposed material was transferred to a new tube. An additional 1 mL of sulfuric acid and 2 mL of hydrogen peroxide were added to this solution. The plant material was completely decomposed by heating this solution at 200°C for 30 minutes. (Quantitative determination of phosphate) The above decomposition product was diluted 200 times with ultrapure water. Acidic molybdenum solution and acidic ascorbic acid solution were added to induce color development. This was transferred to a 96-well plate, and the absorbance was measured using a plate reader to calculate the concentration. A comparison of the total amount of phosphorus contained in the roots revealed that the group with 0.05% by volume of onion extract showed a 23.1% weight increase compared to the control group, while the group with 0.1% by volume of onion extract showed a 10.7% weight increase (Figure 4). Therefore, it was demonstrated that onion extract has the effect of promoting phosphorus absorption from the roots.

[0055] [Example 3] We evaluated whether onion powder increases root weight, which is important for fertilizer absorption, using rice plants.

[0056] (Preparation of onion powder) Onion powder was obtained by drying 100g of onion bulbs cut into 1-10mm intervals and then grinding them.

[0057] (seedling raising period) Seedlings were grown in the same manner as in Example 1. (Exam period) Rice plants grown as described above were transferred to a container containing 900 mL of hydroponic solution prepared in the same manner as in Example 1. Three test groups were designed: one with 0.45 g or 0.9 g of onion powder added to achieve a final concentration of 0.05% by mass or 0.1% by mass, and one without onion powder (control group). After cultivating the three test groups in an artificial climate chamber, the rice plants were removed, dried, and the roots were collected and weighed. As a result, the test group with 0.05% by mass of onion powder showed a weight increase of 31.4% compared to the control group (Figures 5 and 7). Furthermore, the test group with 0.1% by mass of onion powder showed a weight increase of 26.6% compared to the control group (Figures 6 and 7). From the above, it was shown that onion powder has the effect of increasing root weight.

[0058] [Example 4] The effect of adding onion extract on phosphate absorption was also evaluated using the rice from Example 3.

[0059] (Pretreatment for phosphate determination) Pretreatment was performed in the same manner as in Example 2. (Quantitative determination of phosphate) Similar to Example 2, phosphate was quantified, and compared to the control group, a 23.5% weight increase was observed in the test group with 0.05% by mass of onion powder, and a 7.4% weight increase was observed in the test group with 0.1% by mass of onion powder (Figure 8). These results indicate that onion extract has the effect of promoting phosphate absorption from the roots.

[0060] [Example 5] The changes in gene expression in rice caused by onion extract were also evaluated using the rice from Example 1.

[0061] (Sample preparation) Total RNA was extracted from the roots of rice plants in the control group of Example 1 and the group treated with 0.1 volume% onion extract.

[0062] (RNA extraction) RNA samples were obtained using the Maxwell RSC Plant RNA Kit (Promega) and Maxwell RSC Instrument (Promega) according to the instructions. (RNA quality check) Measuring equipment: Agilent 2100 Bioanalyzer <g2939a>(Agilent Technologies), reagent kit: Agilent RNA6000 Nano kit <5067 - 1511> (Agilent Technologies) and analysis software: 2100 expert software <version B.02.07> (Agilent Technologies) were used. After confirming that there were no problems with the quality of the RNA samples, they were used for library preparation. (Library preparation) A library for the NextSeq next-generation sequencer was prepared using the QuantSeq 3'mRNA-Seq Library Prep Kit according to the following steps. 1 Use 100 ng of total RNA 2 Synthesize cDNA using oligo(dT) primers 3 Remove template mRNA 4 Synthesize double-stranded cDNA using random primers 5 Perform 14-cycle PCR using indexed adapters 6 Purify using beads

[0063] (Analysis by next-generation sequencer) · Sequence analysis Equipment: NextSeq500 (Illumina) Reagent: NextSeq 500 / 550 High Output Kit v2.5 (75 Cycles) <2002490>6> (Illumina) · Sequence (outline) <00-00312>Sequencing was performed using NextSeq500 according to the following steps. 1 Add sequencing reagent 2 Perform single-base extension reaction 3 Remove unreacted bases 4 Capture fluorescence signal 5 Remove protecting group and fluorescence 6 Repeat cycles of 2Cycle…3Cycle… and perform up to 75 cycles

[0064] (Data analysis) • Primary data analysis Analysis program: bcl2fastq ver2.20 (Illumina Corporation) A fastq file was created from the obtained reads using the program bcl2fastq (Illumina). • Secondary data analysis Operating System of the analysis computer: Ubuntu Desktop 22.04.4 LTS Analysis software: FastQC, hisat2, samtools, HTSeq, DESeq2 The analysis was performed using the software described above. 1. Checking the quality of the reeds We used FastQC to verify the quality of the bases contained in the obtained fastq file. 2. Mapping and Sorting The data was mapped to the Oryza sativa reference genome, Oryza sativa Japonica Group (assembly IRGSP-1.0), using hisat2. Subsequently, the files were sorted and converted to binary data using samtools. 3 Lead Count The number of mapped reads was counted using the htseq-count within the HTSeq. 4 Statistical analysis Using the DESeq2 package on the statistical package R, we compared gene expression levels in the control group and the group treated with onion extract. • Third-level data analysis We searched the Rice Annotation Project (https: / / rapdb.dna.affrc.go.jp / ) for genes reported to be involved in phosphate absorption in previous studies. We then searched for these genes in the gene expression list created for this experiment.

[0065] Gene expression analysis revealed that in the onion extract-added group, the expression level of phosphate absorption-related genes in the roots increased 3.27 times (Figure 9). The enzyme associated with this phosphate absorption-related gene has been reported to date, and is therefore thought to contribute to the increased phosphate absorption mentioned above. It is located on the surface of the root and directly interacts with phosphorus present in the environment (Reference 1). Increased expression of this gene under phosphorus-deficient conditions leads to increased phosphate absorption (Reference 1). This gene and similar genes have been reported to be widely present not only in Arabidopsis thaliana and rice, but also in wheat, chili peppers, lettuce, tomatoes, cocoa, etc. (References 2 and 3). Based on the above, it is thought that onion extract has the effect of promoting phosphate absorption in many plants other than rice by stimulating phosphate absorption-related genes or similar molecules.

[0066] Reference 1: https: / / bmcplantbiol.biomedcentral.com / articles / 10.1186 / s12870-020-2316-7 Reference 2: https: / / onlinelibrary.wiley.com / doi / 10.1111 / plb.12668 Reference 3: https: / / www.arabidopsis.org / locus?key=27574

Claims

1. A plant growth promoting composition comprising one or more substances selected from the group consisting of onion extract and onion powder as an active ingredient.

2. The plant growth promoting composition according to claim 1, which has a phosphoric acid absorption promoting effect.

3. The plant growth promoting composition according to claim 2, which increases the expression level of phosphate absorption-related genes.

4. The plant growth promoting composition according to claim 2, further having an effect of improving stress tolerance to one or more stresses selected from the group consisting of chemical stress, including nutrient deficiency stress or nutrient excess stress, pH stress, and salt stress.

5. The plant growth promoting composition according to claim 4, which increases the expression level of stress tolerance genes to one or more stresses selected from the group consisting of chemical stress, including nutrient deficiency stress or nutrient excess stress, pH stress, and salt stress.

6. A plant growth promoting composition according to any one of claims 1 to 5, having one or more plant growth promoting effects selected from the group consisting of elongation or increase in weight of stems, leaves or roots, increase in the number of leaves, promotion of flowering or fruiting, increase in the number of flowers or fruits, increase in plant weight or crop yield, greening, and promotion of tillering.

7. A method for promoting plant growth, comprising using a plant growth promoting composition containing one or more selected from the group consisting of onion extract and onion powder as an active ingredient, on a plant, or on the soil or culture medium in which the plant grows.

8. The plant growth promoting method according to claim 7, wherein the amount of the plant growth promoting composition used in the culture medium or diluent is 0.001 to 50% by mass or 0.001 to 50% by volume.

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