Seeds of gramineous plants, method for alleviating germination inhibition of plant seeds caused by excess moisture stress, and use thereof

Abstract

To provide plant-derived compounds that alleviate the germination inhibition of plants caused by excess moisture stress, treatment methods using the same, and plant seeds treated by the methods.SOLUTION: A seed according to one embodiment of the present invention is a seed of a plant that comprises at least one compound selected from safranal and safranal analogs, or is treated with the compound, wherein the plant is a gramineous plant.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to seeds of grasses, a method for reducing germination inhibition of plant seeds caused by moisture damage, a method for producing seeds of grasses, a growth regulator for reducing germination inhibition of plant seeds caused by moisture damage, and a growth regulator kit for reducing germination inhibition of plant seeds caused by moisture damage. [Background technology]

[0002] Wheat is a crop that is sensitive to excessive moisture, but in Japan, where there is a lot of precipitation and it is often grown on fields converted from rice paddies that are prone to poor drainage, it is prone to moisture damage. When wheat suffers moisture damage, germination and growth are inhibited, resulting in reduced yields and quality. Techniques to solve this type of growth disorder caused by moisture damage in wheat include breeding and soil improvement.

[0003] In addition, physical or chemical treatment of crops is also effective in reducing growth disorders caused by moisture damage. For example, Non-Patent Document 1 describes that by performing a priming treatment by flooding before a flooding stress treatment, growth disorders in wheat under a flooding stress environment after flowering are alleviated, that the expression level of proteins involved in ethylene biosynthesis is high in wheat leaves after priming treatment, and that by treating wheat with 1-aminocyclopropanecarboxylic acid (ACC), an ethylene precursor, before flooding, the opening of stomata is promoted even under flooding stress, thereby promoting photosynthesis in the leaves. Non-Patent Document 2 describes that when ACC is treated before the roots of wheat are exposed to a low-oxygen environment, the accumulation of ethylene in the roots is promoted, and gene expression of enzymes involved in ethanol fermentation and generation of active oxygen is increased. Non-Patent Document 3 describes that the formation of aerenchyma in the root cortex, which is one of the response mechanisms of grasses to an overly humid environment, is promoted by the accumulation of ethylene and active oxygen in the body due to a decrease in the oxygen concentration in the soil. Non-patent literature 4 describes how treating wheat after sowing with an aqueous solution (smoke water) that has been passed through smoke produced when plants are burned regulates photosynthesis and glycolysis even under flooding stress, thereby reducing growth inhibition. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Wang et. al.,Physiological and proteomic mechanisms of waterlogging priming improves tolerance to waterlogging stress in wheat (Triticum aestivum L.), Environmental and Experimental Botany, 132,p.175-182,2016 [Non-Patent Document 2] Yamauchi et.al., Ethylene and reactive oxygen species are involved in root aerenchyma formation and adaptation of wheat seedlings to oxygen-deficient conditions, Journal of Experimental Botany, 65,p.261-273,2014 [Non-Patent Document 3] Yamauchi and Nakazono, Morphological responses and adaptation mechanisms of roots of grasses to excessive moisture, Root Research, 24(1), p.23-35, 2015 [Non-Patent Document 4] Komatsu et al., Morphological, biochemical, and proteomic analyzes to understand the promotive effects of plant-derived smoke solution on wheat growth under flooding stress, Plants, 11, 1508, 2022 Summary of the Invention [Problem to be solved by the invention]

[0005] It has been reported that some compounds produced by plants have the function of improving plant growth disorders caused by environmental stress. If plant-derived compounds with useful functions could be used in technologies to reduce growth disorders in crops that are susceptible to moisture damage, it could contribute to the development of new biostimulants and to improving productivity through inexpensive and labor-saving methods. However, there is still a lack of knowledge about plant-derived compounds that reduce crop growth disorders caused by moisture damage.

[0006] An object of one aspect of the present invention is to provide a plant-derived compound that reduces germination inhibition in wheat caused by moisture damage, a treatment method thereof, and plant seeds treated by said method. [Means for solving the problem]

[0007] The present inventors have conducted extensive research to achieve the above object, and as a result have found that the inhibition of plant emergence caused by moisture damage can be reduced by contacting steam containing at least one compound selected from safranal and its analogues with unsown plant seeds.

[0008] That is, one aspect of the present invention is (1) A seed of a plant, which is treated with at least one compound selected from the group consisting of safranal and safranal analogues, and the plant is a grass family plant. (2) A method for reducing inhibition of germination of plant seeds caused by moisture damage, comprising a safranal treatment step of contacting the seeds with at least one compound selected from safranal and safranal analogues. (3) A method for producing a plant seed, comprising a safranal treatment step of contacting or applying at least one compound selected from safranal and safranal analogues to the seed, wherein the plant is a grass family plant. (4) A plant growth regulator for reducing inhibition of plant emergence caused by moisture damage, the growth regulator comprising at least one compound selected from safranal and its analogues. (5) A plant growth regulation kit, comprising at least one compound selected from safranal and safranal analogues, for reducing inhibition of plant emergence caused by moisture damage; It is. Effect of the Invention

[0009] According to one aspect of the present invention, an object is to provide a method for reducing germination inhibition in plants caused by moisture damage more simply than conventional techniques, and plant seeds treated by said method. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a graph showing the effect of safranal treatment on the emergence rate of wheat after flooding treatment in an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <Characteristics of the seeds according to one embodiment of the present invention> The seeds in one embodiment of the present invention are seeds of a plant that contains or has been treated with at least one compound selected from safranal and safranal analogues (hereinafter sometimes referred to as "safranal, etc."), and the plant is a grass family plant.

[0012] The seeds according to one embodiment of the present invention can be obtained by a method that is simpler than the conventional techniques, for example, by contacting the seeds with safranal, a volatile substance derived from a plant. Thus, it is possible to more easily provide plant seeds that have the effect of reducing germination inhibition caused by moisture damage. Another advantage of the seeds according to one embodiment of the present invention is that the desired effect can be obtained by contacting a compound such as safranal with the seeds or germinated seeds of the plant without the need for a large amount of spraying on the soil after sowing.

[0013] The following describes the problem of germination inhibition caused by moisture damage, which is solved by one embodiment of the present invention. Moisture damage generally refers to a phenomenon in which crops suffer growth disorders due to a lack of air in the soil caused by excess moisture in the soil. It is known that an excess moisture environment can cause crop germination inhibition, a decrease in the germination rate, growth suppression and growth retardation after germination, etc.

[0014] In this specification, "moisture damage" has the same meaning as it is generally used, and includes, for example, flooding damage, water damage caused by partial inundation of a plant body during the growth period after germination, etc. In this specification, "reduction of germination inhibition" means that the germination rate is improved compared to a plant exposed to an excessively watery environment in which no measures against moisture damage are taken.

[0015] As described above, according to one aspect of the present invention, it is possible to contribute to a stable supply of crops and increased yields by reducing germination inhibition caused by moisture damage, and therefore to ensure a sustainable food production system, thereby contributing to the achievement of Goal 2 "Zero Hunger" of the Sustainable Development Goals (SDGs) led by the United Nations.

[0016] <Plant seeds> The seed according to one embodiment of the present invention may be a pre-germination or pre-emergence seed. In this specification, "germination" refers to a mature seed or the like obtaining an appropriate temperature and moisture and sprouting. The seed according to one embodiment of the present invention may be in a dry state, and is preferably in a water-absorbed state or in a state in which the seed has been absorbed and then dried again (so-called "primed seeds"). Here, the water-absorbed state refers to a state in which the seed contains water from the outside in addition to the moisture contained in the seeds that are dry and dormant. Conversely, the dry state refers to the state of the seeds that are dormant. In a preferred example, the water-absorbed seeds refer to seeds in a state in which dormancy has been broken.

[0017] (plant) The seed according to one embodiment of the present invention is a seed of a grass family plant, and preferably a seed of a grass family crop or green manure plant. Examples of the grass family plant include wheat, barley, rice, rye, oats, corn, foxtail millet, barnyard millet, etc. Preferred are wheat, barley, and rice, more preferably wheat and barley, and particularly preferably wheat.

[0018] (Compounds such as safranal) The seeds according to one embodiment of the present invention contain or are treated with a compound such as safranal, which is represented by the following general formula (I) or (II): [ka] In the general formula (I), R 1 is an aldehyde group or a carboxyl group, and R 2 , R 3 and R 4 are each independently an alkyl group having 1 to 5 carbon atoms, and among these, a methyl group or an ethyl group is preferable. In addition, in the alkyl group having 1 to 5 carbon atoms, some of the hydrogen atoms may be substituted with halogen atoms. In addition, in the general formula (II), R 1 is an aldehyde group or a carboxyl group, and R 2 , R 3 and R 4are each independently an alkyl group having 1 to 5 carbon atoms, and among these, a methyl group or an ethyl group is preferred. In addition, in the alkyl group having 1 to 5 carbon atoms, a part of the hydrogen atoms may be substituted with a halogen atom. Specific examples of the compound such as safranal represented by the general formula (I) include safranal (2,6,6-trimethylcyclohexa-1,3-diene-1-carbaldehyde) and 2,6,6-trimethylcyclohexa-1,3-diene-1-carboxylic acid. Specific examples of the compound such as safranal represented by the general formula (II) include β-cyclocitral (2,6,6-trimethylcyclohexene-1-carbaldehyde) and β-cyclocitric acid. Compounds such as safranal are known compounds and are available as commercial products.

[0019] In this specification, "containing a compound such as safranal" means that a compound such as safranal is contained in the seed. The location where the compound is contained is not particularly limited, and the compound may be attached to the surface of the seed. Furthermore, "treated with the compound" means that the seed has come into contact with a compound such as safranal. For example, it is sufficient that the seed has come into contact with safranal, and it is not necessary that the compound such as safranal remains in the seed.

[0020] <Methods to reduce germination inhibition caused by moisture damage> The method for reducing germination inhibition in plants caused by moisture damage according to one embodiment of the present invention (hereinafter, may be referred to as the "reduction method") includes a safranal treatment step of contacting the seeds or the plant itself with safranal. With this configuration, it is possible to provide a method for reducing germination inhibition in plants caused by moisture damage more simply than before.

[0021] (Safranal processing process) The safranal treatment step is a step of contacting the seeds of the plant with safranal.

[0022] The form of the compound such as safranal that is brought into contact with the plant seeds is not particularly limited, and may be, for example, a solid or gas containing the compound such as safranal. From the viewpoint of a simpler treatment method, it is preferably vapor obtained by volatilizing the compound such as safranal.

[0023] When the concentration of the compound such as safranal that is brought into contact with the seeds is vapor obtained by volatilizing the compound such as safranal, the concentration contained in the air is preferably 10.0 μmol / L or less, more preferably 8.0 μmol / L or less, and is preferably 1.0 μmol / L or more, more preferably 6.0 μmol / L or more, and even more preferably 7.5 μmol / L or more. By being in this range, the inhibition of plant germination caused by moisture damage can be more suitably reduced.

[0024] Compounds such as safranal may be mixed with other components. The other components may be any components that do not affect the effects of compounds such as safranal and do not adversely affect plants. Examples of such components include fertilizers such as nitrogen, phosphoric acid, and potassium, soil conditioners such as perlite, vermiculite, and polyethyleneimine-based materials, organic solvents such as hexane, dimethyl sulfoxide, and ethanol, polymer solutions, inorganic minerals, and water.

[0025] The contact of the compound such as safranal with the plant seeds is preferably carried out in a sealed space, from the viewpoint of facilitating contact of the compound such as safranal with the seeds. The safranal treatment can be carried out, for example, as follows. That is, the seeds that have been absorbed with water and filter paper onto which a safranal solution has been dropped are placed in a sealed container, the inside of the sealed container is filled with a predetermined concentration of safranal vapor, and the safranal treatment is carried out for a predetermined period of time (for example, one day).

[0026] The environment in which the safranal treatment is carried out is not particularly limited, and may be, for example, at a temperature of 15° C. to 25° C., preferably at a temperature of 20° C., under atmospheric pressure.

[0027] (Other processes) The method for reducing a pesticide poisoning according to one aspect of the present invention may include a step of imbibing water onto the seeds prior to the safranal treatment step.

[0028] The alleviation method according to one embodiment of the present invention may include a growing step of growing the seeds or plants after the safranal treatment step. The growing method may be performed by a conventional method. In one example, the growing step is performed in a land converted from a paddy field (former paddy field) or a dry paddy field (as a second crop of a paddy field, etc.). In a land converted from a paddy field or a dry paddy field, generally, germination inhibition of plants such as wheat due to moisture damage is likely to occur.

[0029] <Production method of plant seeds> A method for producing seeds according to one embodiment of the present invention includes a safranal treatment step of contacting the seeds with a compound such as safranal, and the plant is a grass family plant. This reduces the inhibition of plant emergence caused by moisture damage. Thus, according to the method for producing seeds according to one embodiment of the present invention, it is possible to obtain plant seeds that have been treated in a simpler manner than the conventional techniques and have the effect of reducing the inhibition of plant emergence caused by moisture damage. The seeds, plants, and safranal treatment step are as described above, and therefore will not be described again. When the seeds are coated seeds having multiple coating layers, safranal may be contained in the coating layers that are not in contact with the seed coat.

[0030] <Growth regulator to reduce plant emergence inhibition caused by moisture damage> A growth regulator for reducing plant emergence inhibition caused by moisture damage according to one embodiment of the present invention (hereinafter simply referred to as "growth regulator") contains a compound such as safranal. By containing a compound such as safranal, it is possible to easily reduce plant emergence inhibition caused by moisture damage. By obtaining such an effect, the growth regulator according to one embodiment of the present invention can also be used as a biostimulant.

[0031] The method of applying the growth regulator according to one embodiment of the present invention is not particularly limited, but examples thereof include seed treatment agents, seed coating agents, and fertilizer compositions.

[0032] The safranal etc. contained in the growth regulator may be one type, or may be two or more types selected arbitrarily from safranal etc. The concentration of the compound such as safranal contained in the growth regulator may be sufficient as long as it can exert its effect, and when it is steamed, the concentration contained in the air is preferably 10.0 μmol / L or less, more preferably 8.0 μmol / L or less, preferably 1.0 μmol / L or more, more preferably 6.0 μmol / L or more, and even more preferably 7.5 μmol / L or more. In addition, the growth regulator may be one in which the concentration of safranal etc. is higher than the concentrations exemplified here, and is diluted when used.

[0033] The growth regulator may contain other components in addition to the compound such as safranal. The other components may be any components that do not affect the effect of the compound such as safranal and do not adversely affect plants, and examples of such components include surfactants, spreading agents, formulation aids, fertilizers, soil conditioners, etc. In addition, the growth regulator may be used in combination with various other drugs in order to enhance the plant growth effect.

[0034] The growth regulator may be in the form of a solid or gas depending on the type of other components to be mixed, such as a powder, tablet, or solution.

[0035] The application time of the growth regulator can be before sowing or after sowing the seeds. The growth regulator can be sprinkled directly on the seeds, applied in the soil, or released into the air where the seeds are present.

[0036] <Growth regulation kit to reduce plant emergence inhibition caused by moisture damage> A growth regulation kit for reducing plant emergence inhibition caused by moisture damage according to one embodiment of the present invention (hereinafter simply referred to as the "growth regulation kit") includes a compound such as safranal. With this configuration, it is possible to reduce plant emergence inhibition caused by moisture damage more easily than with conventional techniques. The compound such as safranal has been described above, and therefore the same description will not be repeated.

[0037] The growth regulation kit according to one embodiment of the present invention may include a compound such as safranal, and may include other components as necessary. For example, the growth regulation kit according to one embodiment of the present invention may include plant seeds, a container for safranal treatment, a cultivation container, and instructions for use of the growth regulation kit. The plant seeds that may be included in the growth regulation kit according to one embodiment of the present invention are not particularly limited. In addition, the instructions for use of the growth regulation kit may include, for example, an example of a specific procedure for carrying out the reduction method according to one embodiment of the present invention.

[0038] 〔summary〕 The seeds according to this embodiment are seeds of a plant that contains at least one compound selected from safranal and safranal analogues or that has been treated with said compound, and the plant is a grass family plant.

[0039] The seeds according to this embodiment may be in a state where the seeds have absorbed water.

[0040] The method for reducing germination inhibition in plants caused by moisture damage in this embodiment includes a safranal treatment step of contacting plant seeds or the plant itself with at least one compound selected from safranal and safranal analogues.

[0041] In the alleviation method according to this embodiment, in the safranal treatment step, the concentration of at least one compound selected from safranal and safranal analogues brought into contact with the seeds or plants is 10.0 μmol / L or less.

[0042] The reduction method according to this embodiment may include a step of allowing the seeds to absorb water prior to the safranal treatment step.

[0043] The alleviation method according to this embodiment may include a growing step of growing the seeds after the safranal treatment step.

[0044] In the reduction method according to this embodiment, the safranal treatment step may include contacting the seeds with steam containing at least one compound selected from the group consisting of safranal and safranal analogues.

[0045] The seed production method according to this embodiment includes a safranal treatment step of contacting seeds with at least one compound selected from safranal and safranal analogues, and the plant is a Gramineae plant.

[0046] The growth regulator for reducing plant emergence inhibition caused by moisture damage according to this embodiment contains at least one compound selected from safranal and safranal analogues.

[0047] The growth regulation kit for reducing plant germination inhibition caused by moisture damage according to this embodiment includes at least one compound selected from safranal and safranal analogues.

[0048] The following examples are provided to further explain the embodiments of the present invention. Of course, the present invention is not limited to the following examples, and various modifications are possible in detail. Furthermore, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. The embodiments obtained by appropriately combining the technical means disclosed herein are also included in the technical scope of the present invention. In addition, all of the documents described in this specification are incorporated by reference. EXAMPLES

[0049] [Evaluation example 1] Examination of the effect of safranal treatment on reducing germination inhibition caused by flooding in wheat Wheat seeds (Triticum aestivum L., variety: Norin 61) were placed in a beaker containing purified water and allowed to absorb water for 24 hours at 25°C under dark conditions. The wheat seeds after absorption were placed in a 6L sealed container (29cm wide x 20cm deep x 14cm high) containing a paper towel moistened with purified water. Next, a glass petri dish containing filter paper was placed in the center of the sealed container, and safranal (manufactured by Toronto Research Chemicals, Inc.) was dripped onto the filter paper (1cm x 3cm), sealed, and left to stand for 24 hours at 25°C under dark conditions. The amount of safranal dripped at this time was such that the safranal concentration in the sealed container (the concentration when all the safranal dripped onto the filter paper volatilized into the container) was 0μmol / L (no dripping), 6.0μmol / L, 7.0μmol / L, or 8.0μmol / L, respectively. The concentration of safranal in the closed container was calculated assuming that the droplets of safranal had completely evaporated from the filter paper.

[0050] 150 mL of No. 4 silica sand (grain size: 0-1.5 mm) was placed in a cultivation container (width 65 mm × depth 65 mm × height 81 mm) and the wheat seeds treated with safranal were placed in it. The seeds were then covered with 100 mL of No. 4 silica sand. The cultivation container with the wheat seeds sown was then placed in a 4 L plastic container (width 285 mm × depth 165 mm × height 85 mm) and purified water was added up to the top of the plastic container for flooding treatment. During the flooding treatment, the temperature was kept at 22-25°C on the cultivation shelf and the light period was kept at 12 hours (90-110 μmol m -2 s -1 The plants were left to stand for 88 hours under conditions of a 48-hour light-dark cycle with a 12-hour dark period (48 hours dark, 40 hours light). Purified water was added to the top of the plastic container as needed during this period. After the submersion treatment, all of the purified water in the plastic container was drained, and the plants were cultivated for 10 days under the same temperature and light-dark cycle conditions as those used for the submersion treatment.

[0051] The cultivated groups are shown below. 0μmol / L Safranal treatment + submersion treatment 6μmol / L Safranal treatment + flooding treatment 7μmol / L Safranal treatment + flooding treatment 8μmol / L Safranal treatment + flooding treatment

[0052] <Measurement> After cultivation, the wheat emergence rate was measured. The emergence rate is the ratio of the number of germinated wheat seeds to the total number of seeds sown. The seeds that sprouted from the soil were counted as germinated wheat seeds.

[0053] <Statistical analysis> The experiment under the above conditions was repeated twice in total, and the relationship between safranal concentration and germination rate was analyzed using a generalized linear mixed model (Poisson distribution, log link, and the number representing the order of the repeated experiments as a random variable). The analysis results are shown in Figure 1. The statistical significance probability was P = 0.000246, which is significant.

[0054] [Summary of evaluation examples] Evaluation example 1 demonstrated that by contacting plant seeds with safranal, wheat having the effect of reducing inhibition of plant emergence caused by moisture damage can be obtained more simply than before. [Industrial Applicability]

[0055] According to one aspect of the present invention, a technology for reducing germination inhibition in plants caused by moisture damage can be provided by treating plants with safranal, which is a plant-derived compound, or its analogs, or by treating plants to volatilize these compounds, which can be used as a biostimulant for reducing germination inhibition in plants caused by moisture damage.

Claims

1. A seed of a plant, which is treated with at least one compound selected from the group consisting of safranal and safranal analogues, said plant being a grass family plant.

2. The seed of claim 1 , wherein the seed is in an imbibed state.

3. The seed according to claim 1 or 2, wherein the plant is wheat.

4. A method for reducing inhibition of germination of a seed of a plant, comprising: A safranal treatment step of contacting the seeds with at least one compound selected from safranal and safranal analogues, A method for reducing inhibition of germination of plant seeds caused by moisture damage.

5. The method according to claim 4, wherein in the safranal treatment step, the concentration of at least one compound selected from safranal and safranal analogues contacted with the seeds is 10.0 μmol / L or less.

6. 6. The method according to claim 4 or 5, further comprising imbibing the seeds with water prior to the safranal treatment step.

7. 6. The method of claim 4 or 5, further comprising a growing step of growing said seeds after said safranal treatment step.

8. 6. The method of claim 4 or 5, wherein the safranal treatment step comprises contacting the seeds with steam containing at least one compound selected from the group consisting of safranal and safranal analogues.

9. A method for producing plant seeds, comprising: The method includes a safranal treatment step of contacting or applying at least one compound selected from safranal and safranal analogues to the seeds, The method for producing said plant, wherein said plant is a grass family plant.

10. It is a plant growth regulator, Contains at least one compound selected from safranal and safranal analogues, A growth regulator for reducing inhibition of germination of plant seeds caused by moisture damage.

11. It is a plant growth adjustment kit, The composition comprises at least one compound selected from the group consisting of safranal and safranal analogues, A growth regulation kit for reducing inhibition of germination of plant seeds caused by moisture damage.

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