Plant environmental stress reliever, plant growth promoter, and method for using the same

Abstract

To provide novel plant environmental stress alleviator and plant growth promoter having an excellent effect of reducing environmental stress such as high temperatures.SOLUTION: Provided is a plant environmental stress alleviator or a plant growth promoter, which contains a plant extract containing acetylcholine or an acetylcholinesterase inhibitor and calcium ions. Also provided is a method for alleviating plant environmental stress or a method for promoting plant growth by applying the plant environmental stress alleviator or the plant growth promoter to a plant.SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to an environmental stress reliever for plants, a plant growth promoter, and a method for using the same.

Background Art

[0002] Due to climate change including global warming, abiotic stress on plants has increased, and there are concerns about its impact on yield and quality. In Japan, the temperature rises very high in summer, and plants are subjected to high-temperature stress. Under high-temperature stress, even though the moisture in the floor soil is sufficiently retained, a decrease in germination rate, inhibition of initial growth, excessive growth, and pests and diseases are caused. In addition, in protected cultivation, the night temperature is also difficult to drop, resulting in an environment where it is difficult to produce high-quality vegetables. As countermeasures against high-temperature stress, night cooling seedling raising, highland cold region seedling raising, shading cultivation, etc. can be mentioned, but sufficient methods have not been established.

[0003] In recent years, attention has been focused on the use of biostimulant materials as countermeasures against environmental stress on plants such as high-temperature stress. Currently, biostimulant materials available on the domestic and international markets are made from humus, seaweed, amino acids, minerals, microbial materials, etc. For example, it has been reported that L-arginine promotes the growth of plants under high-temperature conditions (see Non-Patent Document 1).

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the effects of the above biosimulant materials were not sufficient. Therefore, the development of more useful and powerful environmental stress relievers and plant growth promoters has been demanded.

[0006] An object of the present disclosure is to provide a new environmental stress reliever and plant growth promoter for plants that have an excellent alleviating effect against environmental stresses such as high temperature.

Means for Solving the Problems

[0007] As a result of various studies to solve the above problems, the inventors of the present application have found that by applying an extract of eggplant residue, which is one of the unutilized biomass, to plants together with calcium ions, the plants can be imparted with resistance to environmental stresses such as high temperature, and the effect is also greater than that of conventional biosimulant materials. In addition, the inventors of the present application have found that when extracts of unutilized biomass other than eggplant residue are used, effects equivalent to or greater than those of eggplant residue can be obtained, and that these new materials can simplify the manufacturing process and have a simpler usage method compared to conventional biosimulant materials. Based on these findings, the present disclosure has been completed.

[0008] That is, the present disclosure provides an environmental stress reliever for plants containing a plant extract and calcium ions. Further, the present disclosure provides a plant growth promoter containing a plant extract and calcium ions.

[0009] Furthermore, the present disclosure provides a method for alleviating environmental stress of plants by applying the above-described environmental stress reliever for plants to the plants. In addition, the present disclosure provides a method for promoting plant growth by applying the above-described plant growth promoter to the plants.

Effects of the Invention

[0010] In the present disclosure, by applying a plant extract such as eggplant together with calcium ions to a plant, it becomes possible to endow the plant with resistance to environmental stresses such as high temperature, and the effect is greater than that of conventional biostimulant materials. This effect is presumably due to the activation of the high-temperature stress resistance function inherent in the plant by neurotransmitters such as acetylcholine or acetylcholinesterase inhibitors contained in the plant extract and calcium ions, but the detailed mechanism has not yet been elucidated.

[0011] Thus, according to the present disclosure, it is possible to provide a new environmental stress reliever and plant growth promoter having an excellent effect of reducing environmental stresses such as high temperature.

Brief Description of the Drawings

[0012]

Figure 1A

Figure 1B

Figure 1C

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0013] Hereinafter, the environmental stress reliever for plants according to this embodiment will be described in detail. The environmental stress reliever according to this embodiment is characterized by containing a plant extract and calcium ions.

[0014] In this specification, "environmental stress" means abiotic stress that plants undergo, and examples include high-temperature stress, low-temperature stress, salt stress, oxidative stress, and the like. Also, the form of the environmental stress reliever is not particularly limited, but it is preferably in the form of an aqueous solution.

[0015] The plant that is the extraction raw material of the "plant extract" is preferably an unused biomass such as organic waste discharged from a food processing factory or crop residues generated after harvesting in agriculture, from the viewpoints of reducing manufacturing costs and solving the food loss problem. Further, the plant preferably contains a neurotransmitter and / or an acetylcholinesterase inhibitor. The neurotransmitter can be one or more selected from acetylcholine, epinephrine, norepinephrine, serotonin, dopamine, amino acids (particularly glutamic acid, alanine, glycine, proline, leucine, threonine, phenylalanine, GABA, arginine, histidine, cysteine, and asparagine), preferably acetylcholine. The acetylcholinesterase inhibitor can be one or more selected from polyphenols, flavonoids, and organic acids, preferably one or more selected from malic acid, fumaric acid, and tocopherol.

[0016] Since the plant contains the neurotransmitter and / or the acetylcholinesterase inhibitor, for example, eggplant, broccoli, banana, coconut, orange, herbs (coriander, cumin, sage, lemongrass, mugwort, comfrey, sage, shiso, lemon balm, oregano, catnip, common thyme, thyme, dill, dark opal, basil, hyssop, peppermint, spearmint, lamb's ear), dokudami, lavender, marigold, grape, coffee (coffee tree), tea (tea tree), cacao, acacia, cedar, pine, sugarcane, mango, banana, papaya, avocado, apple, cherry, guava, olive, tubers (sweet potato, purple sweet potato (sweet potato rich in purple pigment), potato, yam, taro (such as colocasia, shrimp taro, etc.), konjac potato, etc.), persimmon (persimmon tree), mulberry, blueberry, poplar, ginkgo, chrysanthemum, sunflower, bamboo, citrus fruits (lemon, lime, orange, grapefruit, navel orange, yuzu, kumquat, kabosu, summer orange, hassaku, iyokan, lime, satsuma mandarin, clementine, etc.), strawberry, blackberry, cranberry, raspberry, bilberry, huckleberry, Japanese apricot, peach, plum, pear, European pear, loquat, kiwifruit, mangosteen, shishitou, prune, melon, dragon fruit, kukuo, blackcurrant, cashew, gamazumi, pomegranate, acai, aronia, tomato, soybean, black soybean, adzuki bean, green bean, peanut, black sesame, buckwheat, dattan soba, sesame, red cabbage, urushi, nurude, shungiku, spinach, komatsuna, mitsuba, okra, houttuynia, onion, moringa, garlic, purple onion, asparagus, parsley, eucalyptus, udo, Gymnema sylvestre, senna, dandelion, sugina, fern (such as bracken, horsetail, etc.), oak, kunugi, maple, sequoia, metasequoia, hinoki, akamegashiwa, takanotsume, amacha, akebi, yamukogi, ligustrum, tamshiba, kochia, sarunashi, shiromoji, kuro moji, koshiaura, kusagi, hoonoki, matatabi, banaba, rooibos, raffia, kukuo, kudzu, megusurinoki, urin, melbao, aogiri, suou, brazilian boke, merinjyo, cherry blossom, magnolia, yerba mate, mehirugi, ohirugi, yaeyamahirugi, hamazakuro, nippayashi, hirugidamashi,It can be mugwort, Castanopsis sieboldii, burdock, turmeric, lotus root, chickweed, pine, carrot, pepper, capsicum, bamboo, bamboo shoots, Setaria viridis, cassava, sasamorpha, clove, ginkgo, Lysimachia christinae, radish, mustard, etc., or processed products thereof. Among the above plants, particularly eggplant, tomato, rosemary, sasamorpha, mint, eucalyptus, thyme, lemon balm, pine, coconut, bamboo, plum, gourd, lettuce, soybean, cassava, asparagus, mango, hibiscus, dandelion, Stellaria media, morning glory, cocoa are preferably used. The above plants may be a part of the plant body such as stems, leaves, fruits, roots, seeds, outer skins, buds, flowers, and rhizomes. Two or more of these plants can also be used in combination.

[0017] The "plant extract" may be an extract, extract solution obtained by extracting the above plants with an appropriate extraction solvent, or dried products, purified products, etc. thereof. Also, since it contains components equivalent to the extract, the squeezed juice of the above plants, its concentrate, dried product, purified product, etc. are also regarded as being included in the "plant extract". The concentration of the above plant extract is not particularly limited, but as the solid content mass ratio when applied to plants, for example, in the case of hydroponics, it can be 1,000 ppm to 100,000 ppm, preferably 10,000 ppm to 80,000 ppm.

[0018] The "extraction solvent" is preferably water, hot water, alcohol (especially ethanol), hydrous alcohol (especially hydrous ethanol), petroleum ether, but is not limited thereto.

[0019] The "dried product" is preferably one that has been subjected to treatments such as crushing, pulverizing, and powdering, and a powder with a small particle size is particularly desirable.

[0020] "Calcium ions" can be water-soluble salts of calcium and are not particularly limited as long as they exhibit the environmental stress alleviation or growth promotion effect on the plants of the present disclosure. The calcium ions may be, for example, inorganic salts such as calcium sulfate and calcium chloride, organic acid salts such as calcium lactate, etc., and calcium chloride is particularly preferred. The concentration of the calcium ions is not particularly limited, but as the concentration when applied to plants, for example, in the case of hydroponics, it can be 0.001 mM to 100 mM, preferably 0.01 mM to 10 mM, more preferably 0.1 mM to 1.0 mM, and particularly preferably 0.2 mM to 0.7 mM.

[0021] The environmental stress alleviating agent according to the present embodiment may contain, in addition to the plant extract and the calcium ions, iron ions and other nutrients necessary for the growth of crops, other biostimulant materials, other plant growth promoters, fungicides, insecticides, plant hormone agents, etc., as long as they do not inhibit the environmental stress alleviation or growth promotion effect on the plants of the present disclosure.

[0022] "Iron ions" can be water-soluble salts of iron(II) or iron(III) and are not particularly limited as long as they do not inhibit the environmental stress alleviation or growth promotion effect on the plants of the present disclosure. The iron ions may be, for example, iron(II) chloride, iron(III) chloride, iron(II) sulfate, iron(III) sulfate, etc., and iron(II) chloride is particularly preferred. The concentration of the iron ions is not particularly limited, but as the concentration when applied to plants, for example, in the case of hydroponics, it can be 0.001 mM to 100 mM, preferably 0.01 mM to 10 mM, more preferably 0.1 mM to 1.0 mM, and particularly preferably 0.2 mM to 0.7 mM.

[0023] "Other nutrients necessary for the growth of crops" that can be included in the environmental stress alleviating agent may be, for example, trace elements other than iron (boron, manganese, zinc, copper, molybdenum, etc.) and macronutrients (nitrogen, phosphoric acid, potassium), and the trace elements are preferred, but not limited thereto.

[0024] The plants to which the environmental stress reliever of the present embodiment can be applied are not particularly limited, and examples thereof include vegetables such as leafy vegetables, fruit vegetables, root vegetables, and flower vegetables, grains such as rice and wheat, flowers, fruit trees, etc., and preferably lettuce, shungiku, cabbage, spinach, tomato, eggplant, paprika, etc.

[0025] Next, a method for producing an environmental stress reliever for plants according to the present embodiment will be described. The environmental stress reliever for plants according to the present embodiment can be produced by mixing a plant extract and the calcium ions in the presence of water.

[0026] The plant extract can be obtained by extracting the aforementioned plants using the aforementioned extraction solvent. The extraction conditions are not particularly limited. Also, operations such as purification, concentration, and drying can be performed after extraction.

[0027] The mixing operation of the plant extract and the calcium ions is carried out in the presence of water. Here, the presence of water means any condition under which the plant extract and the calcium ions can react with water as a medium. The amount of water may be at least an amount sufficient to mix and stir the plant extract and the calcium ions, or an amount such that the mixture of the plant extract and the calcium ions becomes wet. When using the squeezed juice or extract of a plant as the plant extract in a liquid state, or when using the calcium ions in the form of an aqueous solution, the two can be directly mixed without adding a new medium.

[0028] As the mixing operation, simple stirring and mixing can be performed with a stirrer or the like, but it can also be carried out using a mixer, a large stirring tank, a vortex, a shaker, etc. The temperature conditions during mixing are not particularly limited, and can be, for example, around room temperature (e.g., 10 to 35 °C). The mixing time can be until the plant extract and the calcium ions are sufficiently in contact, and is not particularly limited.

[0029] The plant environmental stress reliever obtained in this way is considered to have the function of turning on the switches of various stress tolerance mechanisms of plants, such as high temperature tolerance, low temperature tolerance, salt stress tolerance, and oxidative stress tolerance that plants originally have. Therefore, it is expected that the plant environmental stress reliever according to this embodiment can artificially control the environmental stress tolerance mechanism of plants by applying this to plants. For example, when plant cells are exposed to environmental stress such as high temperature, the influx of calcium ions from outside the cell through ion channels is caused. The plant environmental stress reliever of this embodiment is considered to activate calcium signal transduction in the cell by opening this ion channel and endow plants with environmental stress tolerance. There is no particular limitation on the plants to which the environmental stress reliever of this embodiment can be applied.

[0030] In addition, the environmental stress reliever of this embodiment can promote the growth of plants under environmental stress by endowing plants with environmental stress tolerance. Therefore, the environmental stress reliever of this embodiment can also be called a plant growth promoter.

[0031] Next, the usage method of the environmental stress reliever of this embodiment will be described. The environmental stress reliever of this embodiment can be used by applying an effective amount to plants in the same way as conventional fertilizers, plant growth promoters, and biostimulant materials. The effective amount may be an amount that exhibits an environmental stress alleviating or plant growth promoting effect on plants.

[0032] For example, in the case of hydroponic cultivation, a usage method of adding an appropriate amount of the environmental stress reliever of this embodiment to the hydroponic solution is simple and preferable. Also, for example, the environmental stress reliever of this embodiment may be sprayed or applied in an appropriate amount on the leaves of plants. Also, for example, it can be irrigated into the soil where plants are growing, treated on seeds, or mixed with other agricultural materials such as liquid fertilizers, plant growth promoters, and biostimulant materials for use.

[0033] When adding the environmental stress reliever of the present embodiment to a hydroponic solution or other agricultural materials, etc., the addition amount and concentration may be appropriately adjusted so that the concentration of the plant extract or calcium ions contained in the environmental stress reliever is within the above-mentioned range, or so that the environmental stress relief or plant growth promotion effect on the plant is achieved. Also, the timing and frequency of use of the environmental stress reliever can be appropriately set according to the time when the crop is susceptible to environmental stress, etc., and is not particularly limited.

[0034] In addition, the method of use when using the environmental stress reliever of the present embodiment as a plant growth promoter is the same as above.

Examples

[0035] Hereinafter, the present embodiment will be described in detail with reference to examples.

[0036] (Test Example 1) High-temperature tolerance test using young lettuce plants (Part 1) Many vegetables cultivated in Japan have low high-temperature tolerance. Lettuce is also adapted to relatively cool weather conditions, and the optimum growth temperature is 18 - 23°C. In the cultivation of head lettuce at high temperatures, abnormal heads such as oversized heads, small heads, bamboo shoot heads, and midrib protruding heads are likely to occur, and the occurrence of physiological disorders (tip burn) due to Ca deficiency becomes a problem. Conventionally, tests for confirming the high-temperature tolerance of crops based on these symptoms have required about several months. Therefore, the inventor of the present application developed a model experimental system for examining the acquisition of high-temperature tolerance of lettuce through a two-week high-temperature cultivation test by utilizing the fact that in young lettuce plants, the differentiation of flower buds and bolting is induced by high-temperature and long-day conditions, and the stem elongates.

[0037] (1) Preparation of environmental stress reliever using eggplant residue As the eggplant residues, (a) 50 g of the pulp from which the pericarp had been removed after eggplant harvesting, (b) 20 g of the buds removed during eggplant cultivation management, (c) 20 g of the pericarp after eggplant harvesting, and (d) 20 g of the roots after eggplant harvesting were used. Each of these eggplant residues was placed in a 1-L beaker, 700 mL of distilled water was added thereto, and the mixture was heated at 120 °C for 20 minutes. Thereafter, the supernatant was filtered through filter paper, and boric acid (3 g), manganese sulfate (2 g), zinc sulfate (0.22 g), copper sulfate (0.05 g), sodium molybdate (0.01 g), iron sulfate (15 g), and calcium chloride (55 g) were added to the filtrate (eggplant residue extract), and further distilled water was added to obtain 1-L eggplant residue mixtures (a to d) each. In addition, an eggplant residue mixture (a' to d') without addition of calcium ions was prepared in the same manner as above except that calcium chloride was not added, and this was used as a comparative example.

[0038] (2) Hydroponic cultivation test of lettuce seedlings 1 mL each of the following nutrient solutions A to D and 1 mL of any one of the eggplant residue mixtures (a to d, a' to d') prepared above were combined, and further distilled water was added to prepare 1-L hydroponic solutions. The amounts of the nutrient solutions used for the preparation of each hydroponic solution (1 L) are shown in Table 1. The concentrations of calcium and trace elements in each hydroponic solution are 0.05 mM of boric acid, 0.01 mM of manganese sulfate, 0.001 mM of zinc sulfate, 0.0003 mM of copper sulfate, 0.0005 mM of sodium molybdate, 0.1 mM of iron sulfate, and 0.5 mM of calcium chloride. The solid content concentrations of the eggplant residue extracts in each hydroponic solution are 50.000 mg / L for the pulp (a, a'), 20.000 mg / L for the buds (b, b'), 20.000 mg / L for the pericarp (c, c'), and 20.000 mg / L for the roots (d, d').

[0039] Nutrient solution A: 700 mL of distilled water and KNO 3 202 g were placed in a 1-L beaker, stirred until dissolved, and further distilled water was added to make 1 L. Nutrient solution B: 700 mL of distilled water and KH 2 PO 4 178 g were placed in a 1-L beaker, stirred until dissolved, and further distilled water was added to make 1 L. Nutrient solution C: 700 mL of distilled water and NH 4NO 3 Put 44 g, stir until dissolved, and further add distilled water to make 1 L. Nutrient solution D: In a 1 L beaker, put 700 mL of distilled water and MgSO 4 ·7H 2 O 489 g, stir until dissolved, and further add distilled water to make 1 L.

[0040] The prepared hydroponic solutions were each put into a 1.2 L simple hydroponic cultivator, and lettuce seedlings (10 days after sowing) were planted and cultivated for 14 days under the cultivation conditions of 12 h light period / 35 °C, 12 h dark period / 25 °C, and humidity 60%. Note that as a control group, a hydroponic solution prepared without adding the eggplant residue mixture (a~d, a’~d’) was used. After 14 days of cultivation, the lettuce was harvested and the yield was measured.

[0041]

Table 1

[0042] (3) Results and Discussion The results are shown in Table 2. The numerical values in Table 2 represent the relative yields (% of fresh weight ratio) in each treatment group when the yields of each control group (nutrient solutions A~D only) are set to 100%. From Table 2, it was shown that the treatment groups using the hydroponic solutions added with the eggplant residue extract and calcium ions (calcium chloride) had a significantly increased yield of 4 to 10.5 times compared to the treatment groups of the comparative examples using the hydroponic solutions without adding calcium ions. From this result, it was found that by adding the environmental stress reliever of this embodiment to the hydroponic solution for cultivation, the growth of lettuce seedlings was greatly promoted under high temperature conditions (25 °C~35 °C), and high temperature stress tolerance was imparted.

[0043]

Table 2

[0044] (Test Example 2) High Temperature Tolerance Test Using Lettuce Seedlings (Part 2) Next, the influence of the change in calcium concentration on the high temperature stress relief effect was examined.

[0045] (1) Preparation of environmental stress reliever using eggplant residues As eggplant residues, 20 g of buds removed during the cultivation management of eggplant and 50 g of fruits (with peel) after eggplant harvest were used. These eggplant residues were each placed in a 1 L beaker, 1000 mL of distilled water was added thereto, and heated at 120 °C for 20 minutes. Then, the supernatant was filtered through filter paper, and boric acid (3 g), manganese sulfate (2 g), zinc sulfate (0.22 g), copper sulfate (0.05 g), sodium molybdate (0.01 g), iron sulfate (15 g), calcium chloride (55 g or 110 g) were added to the filtrate (eggplant residue extract), and further distilled water was added to obtain 1 L of each of the eggplant bud mixture and the eggplant fruit mixture. In addition, an eggplant bud mixture and an eggplant fruit mixture without addition of calcium ions were prepared in the same manner as above except that calcium chloride was not added, and used as comparative examples.

[0046] (2) Hydroponic cultivation test of lettuce seedlings 1 mL each of nutrient solutions A to D of Test Example 1 and 1 mL of either the eggplant bud mixture or the eggplant fruit mixture prepared above were combined, and further distilled water was added to prepare 1 L of a hydroponic solution. The amounts of nutrient solutions used for the preparation of each hydroponic solution (1 L) are shown in Table 3. The concentrations of calcium and trace elements in each hydroponic solution are 0.05 mM of boric acid, 0.01 mM of manganese sulfate, 0.001 mM of zinc sulfate, 0.0003 mM of copper sulfate, 0.0005 mM of sodium molybdate, 0.1 mM of iron sulfate, and 0.5 mM or 1.0 mM of calcium chloride. The solid content concentration of the eggplant residue extract in each hydroponic solution is 20,000 mg / L for buds and 50,000 mg / L for fruits.

[0047] The prepared hydroponic solutions were each placed in a 1.2 L simple hydroponic cultivator, lettuce seedlings (10 days after sowing) were planted, and cultivated for 14 days under cultivation conditions of 12 h light period / 35 °C, 12 h dark period / 25 °C, and humidity 60%. As a control group, a hydroponic solution added with a predetermined amount of calcium chloride aqueous solution was used instead of the eggplant bud mixture and the eggplant fruit mixture. After 14 days of cultivation, the lettuce was harvested and the yield was measured, and the Ca concentration in the plant was measured using an ICP emission spectrometer.

[0048]

Table 3

[0049] (3) Results and Discussion The results are shown in Table 4 and Figures 1A, B, C, 2, and 3. Figures 1A, B, and C are photographic diagrams showing the state of the high-temperature resistance test. Figure 1A shows the treatment group without calcium addition, Figure 1B shows the treatment group with 0.5 mM calcium, and Figure 1C shows the treatment group with 1.0 mM calcium. Figure 2 is a graph showing the measured values of lettuce yield, and Figure 3 is a graph showing the relationship between lettuce yield and calcium concentration. The numerical values in Table 4 and Figure 2 represent the relative yields (%, fresh weight ratio) in each treatment group when the yield of each control group is set to 100%.

[0050] In Figure 1A (without calcium addition), the leaves of all treatment groups turned yellow, and symptoms of calcium deficiency due to high-temperature damage appeared. However, in Figure 1B (0.5 mM calcium), compared with the control group (untreated) without the addition of eggplant residue extract, no high-temperature damage to the leaves was observed in the treatment group with the addition of eggplant residue extract, and the growth was clearly promoted. In Figure 1C (1.0 mM calcium), no leaf damage was observed in the control group (untreated), but a clear growth-promoting effect was observed in the treatment group with the addition of eggplant residue extract.

[0051] From Table 4 and Figure 2, it was shown that in the treatment groups using the hydroponic solution added with eggplant residue extract and calcium ions (calcium chloride), the yields were significantly increased by 2 to 6.5 times compared with each control group using the hydroponic solution without the addition of eggplant residue extract at any calcium ion concentration. On the other hand, in the treatment group without calcium ions, no significant difference was observed compared with the control group (nutrient solutions A to D only). From these results, it was shown that by adding the environmental stress reliever of the present embodiment to the hydroponic solution for cultivation, the growth of lettuce seedlings was greatly promoted under high-temperature conditions (25°C to 35°C), and high-temperature stress tolerance was imparted.

[0052] In FIGS. 3(B) and 3(C), it was shown that the calcium ion concentration increased in the treatment section to which the environmental stress reliever of the present embodiment was applied. Further, since the yield tends to increase as the calcium ion concentration in the plant increases, it was suggested that the increase in the calcium ion concentration is related to the acquisition of high temperature tolerance. As described above, it is considered that an increase in the calcium ion concentration in the cell turns on the switches of various stress tolerance mechanisms in plants. Therefore, it was speculated that the environmental stress reliever of the present embodiment has an effect of alleviating various environmental stresses other than high temperature stress.

[0053]

Table 4

[0054] (Test Example 3) Comparison with unused biomass other than eggplant residue The environmental stress reliever of the present embodiment was prepared using unused biomass other than eggplant residue, and the effects were compared.

[0055] (1) Preparation of environmental stress reliever The following various crop residues shown in Table 5 were used. Each crop residue in the amount shown in Table 5 was placed in a 1 L beaker, 700 mL of distilled water was added thereto, and the mixture was heated at 120°C for 20 minutes. Then, the supernatant was filtered through filter paper to obtain a filtrate (crop residue extract). To this filtrate, boric acid (3 g), manganese sulfate (2 g), zinc sulfate (0.22 g), copper sulfate (0.05 g), sodium molybdate (0.01 g), iron sulfate (15 g), and calcium chloride (55 g) were added, and further distilled water was added to obtain 1 L of each crop residue mixture.

[0056]

Table 5

[0057] (2) Hydroponic cultivation test of lettuce seedlings 1 mL each of nutrient solutions A to D of Test Example 1 and 1 mL of any one of the various crop residue mixtures prepared above were combined, and further distilled water was added to prepare 1 L of a hydroponic solution. The solid content concentration of the crop residue extract in each hydroponic solution was 10,000 mg / L.

[0058] The prepared hydroponic solutions were each placed in a 1.2 L simple hydroponic cultivator, and lettuce seedlings (10 days after sowing) were planted and cultivated for 14 days under cultivation conditions of 12 h light period / 35 °C, 12 h dark period / 25 °C, and humidity 60%. As a control, a hydroponic solution to which 1 mL of a 0.5 M calcium chloride aqueous solution was added instead of the crop residue mixture was used. Also, as a comparative example, a hydroponic solution to which humic substances (humic acid 0.3 g / L) and amino acids (glutamic acid 0.1 mM), which have been reported to have a conventional high-temperature stress-relieving effect, were added instead of the crop residue mixture was used. After 14 days of cultivation, the lettuce was harvested and the yield was measured.

[0059] (3) Results and Discussion The results are shown in Table 6 and Figure 4. The numerical values in Table 6 and Figure 4 represent the relative yields (% of fresh weight ratio) in each treatment group when the yield of the control group is set to 100%. From Table 6 and Figure 4, it was shown that the treatment groups using the hydroponic solution added with the crop residue extract and calcium ions (calcium chloride) had a significantly increased yield of 2 to 11 times compared to the control group using the hydroponic solution without the addition of the crop residue extract. In particular, the environmental stress relievers using eggplant, tomato, rosemary, sasakusa, mint, eucalyptus, thyme, lemon balm, pine, coconut, bamboo, plum, cucurbit, lettuce, soybean, cassava, asparagus, mango, hibiscus, dandelion, shepherd's purse, morning glory, cacao showed remarkable effects compared to the humic substances and amino acids of the prior art. From this result, it was found that the environmental stress reliever of the present embodiment can confer high-temperature stress tolerance to plants even when plant extracts other than eggplant are used.

[0060]

Table 6

[0061] (Test Example 4) High-temperature stress reduction effect by standard substances The plant environmental stress reliever of the present embodiment is considered to activate intracellular Ca signal transduction and endow plants with environmental stress tolerance. Also, in Test Example 2, it was suggested that there is a correlation between the improvement of high-temperature tolerance and the increase in Ca concentration in plants. Therefore, in this test example, the purpose is to contribute to the elucidation of the mechanism of the present disclosure by examining the environmental stress reduction effect when using a standard substance known as a neurotransmitter or acetylcholinesterase inhibitor that causes an influx of Ca ions into cells together with calcium ions.

[0062] (1) Test method Take 20 g each of the standard substances shown in Fig. 5, add boric acid (3 g), manganese sulfate (2 g), zinc sulfate (0.22 g), copper sulfate (0.05 g), sodium molybdate (0.01 g), iron sulfate (15 g), and calcium chloride (55 g) thereto, and further add distilled water to obtain 1 L of each standard substance mixture solution. Next, combine 1 mL each of nutrient solutions A to D in Test Example 1 and 1 mL of any one of the standard substance mixture solutions prepared above, and further add distilled water to prepare 1 L of hydroponic solution. The prepared hydroponic solutions were each placed in a 1.2 L simple hydroponic cultivator, and lettuce seedlings (10 days after sowing) were planted and cultivated for 14 days under cultivation conditions of 12 h light period / 35 °C, 12 h dark period / 25 °C, and humidity 60%. Note that as a control group (untreated), a hydroponic solution added with 1 mL of 0.5 M calcium chloride aqueous solution was used instead of the standard substance mixture solution. Also, as a comparative example, a hydroponic solution added with GABA (final concentration 0.516 g / L), humic acid (final concentration 0.3 g / L), and alanine (final concentration 0.5 g / L), which have been reported to have a conventional high-temperature stress reduction effect, instead of the standard substance, was used. After 14 days of cultivation, the lettuce was harvested and the yield was measured.

[0063] (2) Results and discussion The results are shown in Fig. 5. The numerical values in Fig. 5 represent the relative yields (%, fresh weight ratio) in each treatment plot when the yield of the control plot (untreated) is set to 100%. From Fig. 5, it was shown that the treatment plots using malic acid, fumaric acid, acetylcholine, tocopherol, and succinic acid had significantly increased yields compared to the control plot and the treatment plots of the comparative examples. Acetylcholine is a neurotransmitter known to be contained in many plants, and malic acid, fumaric acid, and tocopherol are all acetylcholinesterase inhibitors contained in plants. From this result, it was suggested that the environmental stress reliever of the present embodiment is highly likely that these acetylcholine and acetylcholinesterase inhibitors act as active ingredients.

Industrial Applicability

[0064] As shown in the above examples, by applying an environmental stress reliever containing a plant extract and calcium ions according to the present disclosure to a plant, it is possible to impart resistance to environmental stress to the plant while maintaining a sufficient growth promoting effect. In addition, the environmental stress reliever of the present disclosure can utilize unused biomass such as crop residues generated in agriculture and waste from food processing factories as raw materials. Therefore, the present disclosure is applicable in the agricultural and food processing industries.

Claims

1. Containing a plant extract and calcium ions, wherein the plant extract contains acetylcholine or one or more acetylcholinesterase inhibitors selected from polyphenols, flavonoids and organic acids, and is an extract of one or more plants selected from the group consisting of eggplant, tomato, rosemary, sasa, mint, eucalyptus, thyme, lemon balm, pine, coconut, bamboo, plum, bitter gourd, lettuce, soybean, cassava, asparagus, mango, hibiscus, dandelion, shepherd's purse, cudweed, morning glory, cacao, an environmental stress reliever for plants.

2. The environmental stress reliever for plants according to claim 1, further containing iron ions and trace elements.

3. The environmental stress reliever for plants according to claim 1, containing the calcium ions at a concentration of 0.001 mM to 100 mM when applied to plants.

4. The environmental stress reliever for plants according to claim 1, which is used by adding it to a hydroponic solution.

5. The environmental stress reliever for plants according to claim 1, which is applied to one or more plants selected from lettuce, shungiku, cabbage, spinach, tomato, and eggplant.

6. Containing a plant extract and calcium ions, wherein the plant extract contains acetylcholine or one or more acetylcholinesterase inhibitors selected from polyphenols, flavonoids and organic acids, and is an extract of one or more plants selected from the group consisting of eggplant, tomato, rosemary, sasa, mint, eucalyptus, thyme, lemon balm, pine, coconut, bamboo, plum, bitter gourd, lettuce, soybean, cassava, asparagus, mango, hibiscus, dandelion, shepherd's purse, cudweed, morning glory, cacao, a plant growth promoter.

7. A method for relieving environmental stress of plants by applying the environmental stress reliever for plants according to any one of claims 1 to 5 to the plants.

8. A method for promoting plant growth by applying the plant growth promoter according to claim 6 to the plants.

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