JP2024044093A - Biostimulant composition, foliar spray agent, and plant cultivation method - Google Patents

Abstract

[Problem] To provide a biostimulant composition that induces disease resistance in plants and has high activity per unit mass. [Solution] The biostimulant composition contains cellotriose and is used to induce disease resistance in plants, and the cellotriose content is 30% by mass or more based on the total mass of glucose and cellooligosaccharides having a polymerization degree of 2 to 10. [Selected Figure] None

Description

The present invention relates to a biostimulant composition, a foliar spray, and a plant cultivation method.

Plant yields are reduced by abiotic stresses such as sunlight hours, temperature, and rainfall, as well as by biotic stresses such as pests and diseases. To date, various fertilizers and pesticides have been used to increase crop yields. Fertilizers are a source of nutrients necessary for plant growth, but do not have the function of alleviating stress. Pesticides directly eliminate pests that parasitize plants and eliminate biotic stress. However, when using pesticides, although their safety has been fully confirmed, there are concerns about the effects on the human body or the environment from overdosing. In particular, there is a concern that pesticides and other chemicals manufactured by chemical synthesis may remain in the soil for a long time once sprayed, so there has been a desire to deal with biotic stress by other methods. For this reason, in addition to these, the use of biostimulants has been attracting attention in recent years as substances that are safe for both the human body and the environment.

"Biostimulants", also called "biostimulants" or "plant revitalizers", contain a wide variety of substances or microorganisms that, when applied to a plant or its root system, stimulate a series of processes that also occur naturally in the plant body, thereby improving the quality of the crop by improving nutrient absorption, increasing fertilization efficiency, and imparting stress resistance. They do not have a direct effect on pests and diseases, and therefore are not classified as any insecticide or fungicide. In other words, biostimulants are naturally occurring components (including microorganisms) that are not plant hormones or nutrients, but that stimulate plant vitality and promote growth even in very small amounts. It is said that applying biostimulants to plants increases the plant's nutrient absorption and nutrient utilization rate, promotes growth, and improves the yield and quality of agricultural crops. Agricultural biostimulants include a variety of formulations such as compounds, substances, and other products that are applied to plants or soil to control and enhance the physiological processes of crops. Biostimulants act on plant physiology through pathways different from nutrients to improve crop vigor, yield, quality and post-harvest storability.

In this way, biostimulants can stimulate the natural abilities of plants to promote their growth without causing the problems associated with traditional pesticides or fertilizers.

Patent Document 1 (JP Patent Publication 63-215606) describes a method for cultivating plants using oligosaccharides, and Example 14 describes the results of investigating the plant growth-promoting effect of cellooligosaccharides with a degree of polymerization of 2 to 10 using radish sprouts.

Japanese Patent Application Laid-Open No. 63-215606

The cellooligosaccharide having a degree of polymerization of 2 to 10 described in Cited Document 1 is a mixture containing a plurality of cellooligosaccharides having different degrees of polymerization. Although Cited Document 1 discusses the amount of cellooligosaccharide added, the active ingredient that promotes plant growth has not been specifically elucidated, and the mechanism of action other than that promoting plant growth has not been disclosed.

An object of the present invention is to provide a biostimulant composition with high activity per unit mass that induces disease resistance in plants.

The present inventors have discovered that cellooligosaccharide with a degree of polymerization of 3, that is, cellotriose, is a compound that has an activity as a biostimulant that induces disease resistance in plants, and that the cellotriose moiety has this activity, The present invention has now been completed.

That is, the present invention includes the following [1] to [5].

[1]
A biostimulant composition containing cellotriose, which is used to induce disease resistance in plants, wherein the content of the cellotriose is 30% by mass or more based on the total mass of glucose and cellooligosaccharides having a polymerization degree of 2 to 10.
[2]
The biostimulant composition according to [1], wherein the total content of glucose and cellobiose is 30% by mass or less based on the total mass of glucose and cellooligosaccharides having a degree of polymerization of 2 to 10.
[3]
A foliar spray agent containing the biostimulant composition according to [1] or [2].
[4]
A plant cultivation method comprising foliar spraying of the biostimulant composition according to [1] or [2].
[5]
Use of cellotriose as a biostimulant to induce disease resistance in plants.

According to the present invention, a biostimulant composition is provided that has high activity per unit mass in inducing disease resistance in plants. This allows the amount (mass) of biostimulant used to be reduced.

1 is an HPLC analysis result of the cellooligosaccharide powder produced in Example 1. 1 shows the results of HPLC analysis of the cellotriose-containing aqueous solution of Example 1. 1 shows the results of HPLC analysis of the cellobiose-containing aqueous solution of Comparative Example 1. 3 shows the results of HPLC analysis of cellotetraose-containing aqueous solution of Comparative Example 2. 1 shows the results of HPLC analysis of the cellopentaose-containing aqueous solution of Comparative Example 3. This is an HPLC analysis result of the cellohexaose-containing aqueous solution of Comparative Example 4. This is an HPLC analysis result of a cellooligosaccharide-containing aqueous solution with a degree of polymerization of 7 to 9 in Comparative Example 5. 1 shows the results of measuring the elicitor activity of aqueous cellooligosaccharide solutions of Example 1 and Comparative Examples 1 to 5. 1 is a graph showing the elicitor activity (mass concentration basis) per 15 ppm of aqueous cellooligosaccharide solutions of Example 1 and Comparative Examples 1 to 5.

The following describes embodiments of the present invention. Note that the embodiments described below are representative examples of the present invention and are not intended to be limiting.

[Use of cellotriose as a biostimulant]
One embodiment is the use of cellotriose as a biostimulant to induce disease resistance in plants.

A biostimulant is a material that has elicitor activity and has the effect of enhancing the immune activity of plants. By applying biostimulants to plants, their defenses against biological stresses such as pests, fungi, molds, and viruses are activated. It can also be used to promote plant growth as an effect associated with activation of plant defenses. Biostimulants may also provide a moderating effect on abiotic stresses such as temperature, light, water, and salt that are related to plant growth.

An elicitor is a general term for a substance that induces a biological defense response in the tissues or cultured cells of higher plants, and induces disease resistance in the plant's immune system. Plants sense elicitors with receptors present on the leaf surface, etc., and initiate a pathogen resistance response. This results in a biological defense action (immunity) in which various compounds are secreted against pathogens, etc. When an elicitor acts on a plant, defense responses such as the synthesis and accumulation of phytoalexins or infection-specific proteins, the production of reactive oxygen species (ROS), the production of reactive nitrogen, callose deposition, MAPK phosphorylation, hypersensitive reactive cell death, and changes in gene expression are induced, and it is believed that these defense responses enable plants to protect themselves from biological stress caused by pathogens and the like, and increase disease resistance.

Phytoalexins are antibacterial compounds that are synthesized and accumulated in plants through the action of elicitors, and different plant species produce different antibacterial compounds. Representative phytoalexins include, for example, flavonoids, terpenoids, and fatty acid derivatives. Reactive oxygen has the ability to kill pathogenic microorganisms. Reactive oxygen and nitrogen function as signals that initiate various defense reactions, either alone or in concert.

Oligosaccharides derived from plant cell walls are a source of damage-associated molecular patterns (DAMPs) that are recognized by pattern recognition receptors leading to the induction of biological defense responses. The present inventors evaluated the elicitor activity of cellooligosaccharides with different degrees of polymerization by using an Arabidopsis transformant containing a luciferase marker gene under the control of the promoter of the transcriptional regulator AtWRKY33 gene as a fluorescent biosensor. As a result, they found that cellotriose is the essential compound and site involved in elicitor activity. The WRKY gene is a regulator of systemic acquired resistance in plants. WRKY genes are a family of transcription factors unique to plants, and are thought to have regulatory functions in response to biological stresses such as pests, pathogens, and other stresses. It is known that most of Arabidopsis' disease defense systems are shared with other plants. Therefore, elicitor activity evaluation using a transformant containing the Arabidopsis WRKY33 gene promoter can be applied to disease resistance in a wide variety of plants. Therefore, based on the above findings of the present inventors, cellotriose can be used as a biostimulant to induce disease resistance in various plants.

[Biostimulant composition]
In one embodiment, the biostimulant composition is used for inducing disease resistance in plants and includes cellotriose. The biostimulant composition contains cellotriose in an amount of 30% by mass or more based on the total mass of glucose and cellooligosaccharide having a degree of polymerization of 2 to 10. The biostimulant composition preferably contains cellotriose in an amount of 40% by mass or more, more preferably 50% by mass, based on the total mass of glucose and cellooligosaccharide having a degree of polymerization of 2 to 10. In one embodiment, the biostimulant composition comprises from 30% to 100% by weight, preferably from 40% to 100% by weight of cellotriose, based on the total weight of glucose and cellooligosaccharides with a degree of polymerization of 2 to 10. Preferably it is contained in an amount of 50% to 100% by mass.

Cellotriose is a cellooligosaccharide with a degree of polymerization of 3, that is, an oligosaccharide in which three glucose units are polymerized through β-glycosidic bonds. Cellotriose preferably has a β-1,4-glycosidic bond, and more preferably has the following chemical structure:

Cellotriose can be obtained by isolating cellotriose from a mixture of cellooligosaccharides. The isolation method is not particularly limited, but HPLC separation is preferred.

Cellooligosaccharides can be obtained by oligomerizing cellulose using enzymatic or chemical methods. There are no particular limitations on the cellulose raw material, but when cellooligosaccharides are obtained by the hydrolysis reaction of cellulose, crystalline fine cellulose such as Avicel (manufactured by Merck) or cotton linter pulp is preferred. Plant biomass can also be used as the cellulose raw material.

The biostimulant composition contains, as cellooligosaccharides other than cellotriose (degree of polymerization: 3), cellobiose (degree of polymerization: 2), cellotetraose (degree of polymerization: 4), cellopentaose (degree of polymerization: 5), cello May contain hexaose (degree of polymerization: 6), celloheptaose (degree of polymerization: 7), cellooctaose (degree of polymerization: 8), cellononaose (degree of polymerization: 9), cellodecaose (degree of polymerization: 10), or a combination thereof. .

In one embodiment, the total content of glucose and cellobiose is 30% by mass or less, preferably 20% by mass or less, and more preferably 10% by mass or less, based on the total mass of glucose and cellooligosaccharides with a degree of polymerization of 2 to 10. Since glucose and cellobiose do not have elicitor activity, by setting the total content of glucose and cellobiose to 30% by mass or less, the elicitor activity per unit mass of the sugar components contained in the biostimulant composition can be increased.

In one embodiment, based on the total mass of glucose and cellooligosaccharides with a degree of polymerization of 2 to 10, the total content of cellooligosaccharides with a degree of polymerization of 4 to 10 is 70% by weight or less, preferably 50% by weight or less, more preferably is 30% by mass or less. Cellooligosaccharides with a polymerization degree of 4 to 10 have cellotriose moieties and therefore have elicitor activity, but compared to these cellooligosaccharides, cellotriose has the highest elicitor activity per unit mass. Therefore, by controlling the total content of cellooligosaccharides with a degree of polymerization of 4 to 10 to 70% by mass or less, the elicitor activity per unit mass of the sugar component contained in the biostimulant composition can be increased.

The biostimulant composition may further include additives. Additives include other plant growth promoters, pesticides, spreading agents, preservatives, suspending agents, thickeners, excipients, solvents, and combinations thereof.

A spreading agent is a viscous liquid whose main component is a surfactant. Examples of the spreading agent include polyoxyethylene nonylphenyl ether, sorbitan fatty acid ester, and polyoxyethylene hexitane fatty acid ester.

Preservatives include, for example, potassium sorbate, paraoxybenzoic acid esters, sodium dehydroacetate, hinokitiol, phenoxyethanol, polyaminopropyl biguanide, and polylysine.

Solvents can be used to facilitate application of the biostimulant composition to plants or to render the biostimulant composition into a liquid composition containing the elicitor active ingredient at a suitable concentration. The solvent is preferably water.

The form of the biostimulant composition is not particularly limited, and examples of the form include liquid, powder, and granule. The biostimulant composition is preferably in liquid form, since it can be easily sprayed as is or diluted to prepare a spray solution.

The biostimulant composition can be produced by mixing cellotriose with other cellooligosaccharides and/or additives as necessary. The cellotriose used in the production of the biostimulant composition may be purified or may be in the form of a mixture with other cellooligosaccharides.

The biostimulant composition may be supplied as a high-concentration stock solution that is diluted at the time of use, or may be supplied as a composition that has been adjusted in advance to the concentration to be used. The stock solution is diluted, for example, 1000 times with water at the time of use and applied to plants. The cellotriose content of the stock solution is preferably 0.05% to 10% by mass, more preferably 0.1% to 8% by mass, and even more preferably 0.5% to 6% by mass.

[How to use biostimulant composition]
The biostimulant composition can be applied to induce disease resistance in various plants. The target plants to which the biostimulant composition is applied are not particularly limited, but are typically agricultural crops, such as Brassicaceae, Solanaceae, Asteraceae, Cucurbitaceae, Chenopodiaceae, Apiaceae, Fabaceae, and Convolvulaceae. Examples include plants of the family Liliaceae, Rosaceae, Malvaceae, Zingiberaceae, Lotus family, and Poaceae.

Specifically, cruciferous plants such as Chinese cabbage, cabbage, broccoli, Japanese radish, komatsuna, mizuna, radish, and turnip, solanaceous plants such as potatoes, tomatoes, eggplants, green peppers, chili peppers, shishito peppers, and tobacco, Chinese chrysanthemum, lettuce, Asteraceae plants such as leaf lettuce, burdock, and butterbur; Cucurbitaceae plants such as watermelon, melon, pumpkin, cucumber, bitter melon, loofah, and gourd; Chenopodiaceae plants such as spinach, common grass, Swiss chard, hijiki seaweed, and beets; carrots , Apiaceae such as celery, parsley, and honeysuckle; Legumes such as soybeans (edamame), adzuki beans, kidney beans, fava beans, peas, deer beans, and peanuts; Convolvulaceae such as sweet potatoes and cabbage; chives, alliums, and onions. , garlic, asparagus and other plants in the lily family, strawberries, apples, pears, loquats and other plants in the rose family, okra and cotton and other plants in the mallow family, ginger and other plants in the ginger family, lotus and other plants in the lotus family, corn, and rice. , barley, wheat, sugarcane, and other grasses. Among these, Cruciferae plants such as cabbage and Komatsuna, Solanaceae plants such as tomatoes and eggplants, Asteraceae plants such as lettuce and leaf lettuce, and Rosaceae plants such as strawberries and apples are preferred, and Komatsuna and tomatoes are more preferred. preferable.

The biostimulant composition is generally diluted to the desired concentration by adding water or the like to the original solution (e.g., diluted 1000 times) and applied to plants at a concentration such that the total content of the elicitor active ingredient in the biostimulant composition is preferably 0.1 mass ppm to 500 mass ppm. The concentration of the elicitor active ingredient in the biostimulant composition is more preferably 0.5 mass ppm to 200 mass ppm, and even more preferably 1 mass ppm to 100 mass ppm. In this disclosure, the "concentration of the elicitor active ingredient" refers to the total concentration of cellotriose and cellooligosaccharides having a cellotriose moiety, for example, cellooligosaccharides having a degree of polymerization of 4 to 10, and when calculating the concentration of the elicitor active ingredient, the mass of the cellooligosaccharide having a cellotriose moiety is a value converted to cellotriose on a substance mass basis. For example, in terms of the concentration of the elicitor active ingredient, 1.00 g of cellotetraose is converted to 0.76 g of cellotriose (= 1.00/666.58 (molecular weight of cellotetraose) x 504.44 (molecular weight of cellotriose)).

The method of applying the biostimulant composition is not particularly limited, and examples thereof include foliar spraying, soil spraying, culture medium spraying, irrigation, and seed application. For soil application, medium application and irrigation, biostimulant compositions may be incorporated into fertilizers. Examples of fertilizers include chemical fertilizers containing nitrogen, phosphoric acid, and potassium; and organic fertilizers such as oil cake, fish cake, bone meal, seaweed powder, amino acids, sugars, and vitamins.

By spraying the biostimulant composition on the leaves, the elicitor activity can be effectively expressed while increasing application efficiency. The method of foliar spraying is not particularly limited, and can be performed using, for example, a power sprayer, a shoulder sprayer, a broadcaster, a sprayer, a manned or unmanned helicopter, a drone, a smoker, a hand sprayer, or the like.

In one embodiment, a method of growing plants is provided that includes foliar spraying a biostimulant composition.

Foliar spraying is preferably performed such that the amount of the elicitor active ingredient sprayed per ^{1 cm2} of the leaf surface is 0.1 ng to 100 ng, and the amount of the elicitor active ingredient sprayed per ^{1 cm2} of the leaf surface is 1 ng to 100 ng. More preferably, the amount is 20 ng. In actual fields, it is difficult to selectively spray only the leaf surface and to make all the sprayed material adhere to the leaf surface, so the concentration of the elicitor active ingredient in the biostimulant composition is The active ingredient of the elicitor is adjusted by dilution to a concentration of 0.01 g to 20 g, preferably 0.1 g to 10 g per ¹⁰⁰ m2 of cultivated area, to a concentration of 0.01 g to 20 g per 100 m2 of cultivated area. It is preferable to spread it evenly over the body. For example, a typical foliar application involves diluting the stock solution of the biostimulant composition 1000 times and applying the resulting diluted solution at 100 L (in some cases 30 L to 200 L) per 10 are (1000 m ² ) of cultivated area. Including spraying. In the case of drone spraying, the stock solution of the biostimulant composition may be diluted 10 times, and 10 L of the resulting diluted solution may be sprayed per 10 are (1000 m ² ) of cultivated area.

In one embodiment, the biostimulant composition is provided in the form of a foliar spray containing the composition.

The timing and number of applications of the biostimulant composition are not particularly limited. For example, the biostimulant composition can be applied before a plant develops a disease, or it can be applied to a plant that has a disease.

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited thereto.

[Example 1]
1. Production of cellooligosaccharides 271 g (moisture content 1.8%, dry mass 266 g) of cotton linter pulp (Toko Kosen Co., Ltd., cellulose content 97%) was mixed with 38 g of 85% by mass phosphoric acid (special grade reagent, Fujifilm Wako Pure Chemical Industries, Ltd.) using a food blender (model number: HBF500S, Hamilton Beach Chemical Industries, Ltd.) to obtain 309 g of reaction raw material (moisture content 3.4%, phosphoric acid content 10.4%).

Subsequently, 30.9 g of the reaction raw material was put into a vibration mill (equipment name: MB-1 type, manufactured by Chuo Kakoki Co., Ltd., pot size 5L) together with 13 kg of φ 3/4 inch carbon steel balls, and the total amplitude was 8 mm. After carrying out a hydrolysis reaction by dry pulverization for 24 hours at a vibration frequency of 16.2 Hz and a jacket water temperature of 75° C., the reaction powder was collected.

10 g of this reaction powder and 90 g of ion-exchanged water were placed in a 200 mL beaker and stirred at 25°C for 1 hour using a magnetic stirrer to obtain a cellulose hydrolysate extract.

Next, 1.3 g of 40% by weight calcium hydroxide aqueous solution was added to the extract, and the mixture was stirred for 1 hour at 25°C using a magnetic stirrer to prepare a neutralized solution. The supernatant was then collected using a centrifuge and freeze-dried to obtain cellooligosaccharide powder.

0.2 g of the obtained cellooligosaccharide powder was dissolved in 10 mL of pure water and analyzed by high performance liquid chromatography (HPLC). The HPLC analysis results are shown in FIG. In FIG. 1, the numbers placed above the peaks indicate the degree of polymerization of cellooligosaccharides (the number 1 refers to glucose).

The detailed analysis conditions were as follows.
HPLC device: Shimadzu Corporation Column: Shodex (registered trademark) OHpak (registered trademark) SB-802.5 HQ (inner diameter 8.0 mm x 300 mm, manufactured by Showa Denko Corporation) x 3, connected in series Eluent: H ₂ O
Flow rate: 0.5mL/min
Detector: Shodex (registered trademark) RI (manufactured by Showa Denko K.K.)
Column temperature: 55℃

2. Production of cellotriose-containing aqueous solution 0.2 g of the obtained cellooligosaccharide powder was dissolved in 10 mL of pure water to obtain a cellotriose-containing solution. The cellooligosaccharide solution was set in an HPLC fractionation device and injected in 50 μL increments. A fraction from 51 to 53 minutes was collected from the eluate from the column. The fractions obtained by 120 injections were combined and concentrated, and the volume was adjusted to 5 mL with pure water. The concentration of the obtained solution was quantified by HPLC analysis under the same analytical conditions as for the cellooligosaccharide powder, and the concentration was adjusted to 50 ppm by mass with pure water to obtain a cellotriose-containing aqueous solution. The HPLC analysis results are shown in FIG. 2.

The detailed preparative conditions were as follows.
HPLC device: Shimadzu Corporation Fractionation device: Fraction collector FRC-10A (Shimadzu Corporation)
Column: Shodex (registered trademark) OHpak (registered trademark) SB-802.5 HQ (inner diameter 8.0 mm x 300 mm, manufactured by Showa Denko K.K.) x 3, connected in series Eluent: H ₂ O
Flow rate: 0.5 mL/min
Detector: Differential refractive index detector RID-10A (manufactured by Shimadzu Corporation)
Column temperature: 55°C

[Comparative Examples 1 to 5]
Using the same method as in Example 1, a cellobiose-containing aqueous solution was obtained from the 53-55 minute fraction (Comparative Example 1), a cellotetraose-containing aqueous solution was obtained from the 49-51 minute fraction (Comparative Example 2), a cellopentaose-containing aqueous solution was obtained from the 47-49 minute fraction (Comparative Example 3), a cellohexaose-containing aqueous solution was obtained from the 46-47 minute fraction (Comparative Example 4), and a cellooligosaccharide-containing aqueous solution having a degree of polymerization of 7 to 9 (containing a mixture of celloheptaose, cellooctanoose, and cellononaose) (Comparative Example 5) was obtained from the 43-46 minute fraction.

HPLC analysis results of cellooligosaccharide-containing aqueous solutions of Comparative Examples 1 to 5 are shown in FIGS. 3 to 7, respectively. For Comparative Example 5, a small amount of cellotriose was mixed for reference of retention time. Therefore, in FIG. 7, a cellotriose peak was observed.

The solid composition of the cellooligosaccharide-containing aqueous solutions of Example 1 and Comparative Examples 1 to 5 is shown in Table 1.

[Elicitor activity measurement]
The elicitor activity of cellooligosaccharides was measured by the following procedure.

The AtWRKY33 gene (AT2G38470) is a gene encoding a transcriptional regulatory factor that plays a central role in the disease resistance response of Arabidopsis. Seeds of an Arabidopsis transformant containing a luciferase marker gene under the control of the AtWRKY33 gene promoter (H. Kato et al., Recognition of pathogen-derived sphingolipids in Arabidopsis, Science, 376(6595), 857-860 (2022)) were surface sterilized for 1 minute with gentle shaking in a sterilizing solution (3% hydrogen peroxide, 50% ethanol), and then washed with sterile water. Thereafter, the sterilized seeds were added to 150 μL of Murashige-Skoog (MS) liquid medium supplemented with luciferin (1/2 mixed salts for Murashige-Skoog medium, 0.05% [w/v] MES, 0.5% [w/v ] sucrose, adjusted to pH 5.8 with NaOH, 50 μM D-luciferin) and sealed with a transparent plastic cover. This plate was left standing in a growth chamber for about 12 days at 23°C with the light on for 24 hours to grow Arabidopsis. After spraying cellooligosaccharide (concentration 15 mass ppm) on grown seedlings, the time-dependent change in chemiluminescence intensity derived from the expressed luciferase was measured eight times using a multiplate reader Mithras LB940 (manufactured by Berthold), and the average I found the value.

Figure 8 shows the results of measuring the elicitor activity of the aqueous cellooligosaccharide solutions of Example 1 and Comparative Examples 1 to 5. Figure 9 and Table 2 show the elicitor activity (mass concentration basis) per 15 ppm of the aqueous cellooligosaccharide solutions of Example 1 and Comparative Examples 1 to 5. Figure 9 and Table 2 also show the results of a control experiment (control) conducted in the same manner as in Example 1 using an aqueous glucose solution. The values in Figure 9 and Table 2 are fluorescence intensity (a.u.).

From FIG. 9 and Table 2, it can be seen that cellotriose has the highest elicitor activity per unit mass. In addition, elicitor activity is observed in cellotriose, cellotetraose, cellopentase, cellohexaose, and cellooligosaccharides with a degree of polymerization of 7 to 9, while no elicitor activity is observed in glucose and cellobiose. It is suggested that this is an elicitor active site.

The biostimulant composition of the present invention can be advantageously used to induce disease resistance in plants.

Claims (5)

A biostimulant composition containing cellotriose, used to induce disease resistance in plants, in which the cellotriose content is 30% by mass or more based on the total mass of glucose and cellooligosaccharides having a degree of polymerization of 2 to 10. The biostimulant composition according to claim 1, wherein the total content of glucose and cellobiose is 30% by mass or less based on the total mass of glucose and cellooligosaccharides with a degree of polymerization of 2 to 10. A foliar spray containing the biostimulant composition according to claim 1 or 2. A method for cultivating plants comprising foliar spraying of the biostimulant composition according to claim 1 or 2. Use of cellotriose as a biostimulant to induce disease resistance in plants.

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