Plant growth regulator and method for inhibiting plant growth

Abstract

One aspect of the present invention is a plant growth regulator comprising at least one member selected from the group consisting of a triester of a carboxylic acid and glycerin, glycerin, and sorbitol.

Description

[Technical field]

[0001] The present invention relates to a plant growth inhibitor, a resin molded product for inhibiting plant growth, a method for inhibiting plant growth, and soil. [Background technology]

[0002] In parks, plazas, farmland including unused farmland, coasts, reclaimed land, road slopes, road shoulders or median strips, vacant lots and other areas, manual, chemical or mechanical weeding is carried out by mowing by hand or with a harvester, spraying herbicides or pesticides, covering with weed control sheets and so on, in order to prevent weeds from impairing crop growth, stabilize crop yields and beautify the environment.

[0003] As herbicides, herbicides using glyphosate are generally known (e.g., Patent Document 1), but since such herbicides kill weeds by killing them, there are concerns about their adverse effects on the natural environment. Therefore, there is a strong demand for herbicides that not only reduce the time and cost required for weeding work, but also reduce the adverse effects of weeding work on the natural environment. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2005-521700 Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, an object of the present invention is to provide a plant growth regulator that can inhibit plant growth and is environmentally friendly, a resin molded product for inhibiting plant growth, and a method for inhibiting plant growth. [Means for solving the problem]

[0006] As a result of intensive research into solving the above problems, the present inventors have found that plant growth can be suitably inhibited by using a triester of carboxylic acid and glycerin, glycerin, or sorbitol. That is, one aspect of the present invention is a plant growth inhibitor containing at least one selected from the group consisting of a triester of carboxylic acid and glycerin, glycerin, and sorbitol. This growth inhibitor does not kill plants, but rather inhibits plant growth, and can reduce adverse effects on nature.

[0007] Another aspect of the present invention is a resin molded product for inhibiting plant growth, comprising the above-mentioned growth inhibitor and a resin. Another aspect of the present invention is a method for inhibiting plant growth, comprising applying the above-mentioned resin molded product to soil. Another aspect of the present invention is soil, comprising the above-mentioned resin molded product of a plant. Effect of the Invention

[0008] According to the present invention, it is possible to provide a plant growth regulator that can inhibit plant growth and is environmentally friendly, a resin molded product for inhibiting plant growth, and a method for inhibiting plant growth. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a perspective view showing a stake-shaped growth retarder in one embodiment. [Diagram 2] FIG. 2 is a perspective view showing a granular growth inhibitor in one embodiment. [Diagram 3] FIG. 2 is a perspective view showing a sheet-shaped growth inhibitor in one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. Note that the present invention is not limited to the following embodiment.

[0011] A plant growth inhibitor according to one embodiment (hereinafter also simply referred to as "growth inhibitor") contains at least one selected from the group consisting of a triester of carboxylic acid and glycerin (hereinafter also simply referred to as "triester"), glycerin, and sorbitol.

[0012] The carboxylic acid constituting the triester may be, for example, a fatty acid. The fatty acid may include a saturated fatty acid or an unsaturated fatty acid. The fatty acid includes one or more types selected from the group consisting of saturated fatty acids and unsaturated fatty acids. When the fatty acid includes two or more types of these fatty acids, the fatty acid may include both saturated fatty acids and unsaturated fatty acids.

[0013] The number of carbon atoms in the fatty acid may be, for example, 12 or more, 14 or more, or 16 or more. The number of carbon atoms in the fatty acid may be 30 or less, 25 or less, or 18 or less. The number of carbon atoms in the fatty acid may be 12 to 30, 12 to 25, 12 to 18, 14 to 30, 14 to 25, 14 to 18, 16 to 30, 16 to 25, or 16 to 18, preferably 12 to 30, more preferably 14 to 25, and particularly preferably 16 to 18.

[0014] The fatty acid having 16 to 18 carbon atoms may be linoleic acid, oleic acid, palmitic acid, linolenic acid (α-linolenic acid or γ-linolenic acid), stearic acid, etc. The fatty acid preferably contains at least one selected from the group consisting of linoleic acid, oleic acid, palmitic acid, linolenic acid, and stearic acid, and may contain all of linoleic acid, oleic acid, palmitic acid, linolenic acid, and stearic acid. Triesters composed of these fatty acids are contained in soybean oil, for example. Therefore, the growth inhibitor may contain soybean oil.

[0015] The growth inhibitor may contain at least two of glycerin, sorbitol and a triester, such combinations including glycerin and sorbitol, glycerin and a triester, sorbitol and a triester, and glycerin, sorbitol and a triester.

[0016] The growth inhibitor may consist of at least one active ingredient (growth inhibitor) selected from the group consisting of triester, glycerin, and sorbitol, or may contain other ingredients in addition to the active ingredient. When the growth inhibitor contains other ingredients, the content of the growth inhibitor may be, for example, 0.7% by mass or more, or 1.0% by mass or more, based on the total amount of the growth inhibitor.

[0017] The growth retarder may be a solid or a liquid at 23°C. When the growth retarder is a liquid, for example, the growth retarder may further contain water or a specified solvent. From the viewpoint of being able to prevent the growth retarder from flowing out from a specified place when the growth retarder is applied to the specified place, the growth retarder is preferably a solid. When the growth retarder is a solid, the shape of the growth retarder is not particularly limited.

[0018] Another embodiment of the present invention may be a resin molded product for inhibiting plant growth, comprising the above-mentioned growth regulator and a resin. The shape of the resin molded product is not particularly limited.

[0019] FIG. 1 is a perspective view showing a resin molded body according to one embodiment. As shown in FIG. 1(a), a resin molded body 1 according to one embodiment is molded into a pile shape. The resin molded body 1 includes, for example, a substantially disk-shaped pile head 2 and an elongated pile main body 3 extending from one surface of the pile head 2 in a direction substantially perpendicular to the surface. The cross-sectional shape of the pile main body 3 may be, for example, a cross-shape. The resin molded body 1 is molded into such a shape so that it can be inserted into soil 5 as shown in FIG. 1(b). The tip of the pile main body 3 (the end opposite to the pile head 2) may be pointed so as to facilitate insertion into soil 5.

[0020] The diameter d1 of the pile head 2 (the length in the short direction of the resin molded body 1) may be, for example, 2.0 to 4.0 cm. The length d2 of the resin molded body 1 in the long direction may be, for example, 5.0 to 15.0 cm.

[0021] The content of the growth inhibitor may be, for example, 0.7 mass % or more, or 1.0 mass % or more, based on the total amount of the resin molded article.

[0022] The resin may contain a thermoplastic resin, may contain a thermosetting resin, or may contain both of them. From the viewpoint of excellent moldability, the resin preferably contains a thermoplastic resin.

[0023] The thermoplastic resin may contain a biodegradable thermoplastic resin, may contain a non-biodegradable thermoplastic resin, or may contain both of these. From the viewpoint of exerting the plant growth inhibitory effect more sustainably (excellent sustained release property), the thermoplastic resin preferably contains a biodegradable thermoplastic resin.

[0024] Examples of the biodegradable thermoplastic resin include aliphatic polyester, polyvinyl alcohol, and polyalkylene glycol.

[0025] The resin content may be 10% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, or 98% by mass or more based on the total amount of the resin molded body. When the resin molded body contains a binder described later, the resin content may be, for example, 10% by mass or more, 60% by mass or more, or 70% by mass or more based on the total amount of the resin molded body. When the resin molded body does not contain a binder, the resin content may be, for example, 95% by mass or more, or 98% by mass or more based on the total amount of the resin molded body.

[0026] The content of the thermoplastic resin may be 10% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, or 98% by mass or more based on the total amount of the resin molded body. When the resin molded body contains a binder described later, the content of the thermoplastic resin may be, for example, 60% by mass or more, or 70% by mass or more based on the total amount of the resin molded body. When the resin molded body does not contain a binder, the content of the thermoplastic resin may be, for example, 95% by mass or more, or 98% by mass or more based on the total amount of the resin molded body.

[0027] Examples of aliphatic polyesters include polylactic acid, poly(3-hydroxybutyric acid), polybutylene succinate, polybutylene adipate, polyethylene succinate, polyethylene adipate, polypropylene succinate, polypropylene adipate, polyhexylene succinate, polyhexylene adipate, polyhydroxybutyrate, copolymers of polybutylene succinate and polybutylene adipate, copolymers of polybutylene succinate and polycarbonate, polycaprolactone, polyhydroxybutyric acid, polyhydroxyvaleric acid, polybutylene succinate, polybutylene adipate, polymalic acid, polyglycolic acid, polysuccinic acid esters, polyoxalic acid esters, polybutylene diglycolate, and polydioxanone.

[0028] Examples of polyalkylene glycols include methylene glycol, ethylene glycol, propylene glycol, and diethylene glycol.

[0029] Examples of non-biodegradable thermoplastic resins include polyolefins, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, etc. Examples of polyolefins include polyethylene, polypropylene, polymethylpentene, polybutene, polybutadiene, polystyrene, etc. The polyolefin may be a homopolymer or copolymer of an α-olefin such as polyethylene or polypropylene, or a copolymer of an α-olefin and another comonomer.

[0030] Even if the thermoplastic resin does not have biodegradability, it can be given biodegradability by using it together with an additive that promotes the depolymerization of the thermoplastic resin. Specifically, for example, a polyolefin containing a homopolymer or copolymer of an α-olefin such as polyethylene or polypropylene, or a copolymer of an α-olefin and another comonomer, is given biodegradability by using it together with a metal compound containing at least one selected from the group consisting of a metal salt, a metal oxide, and a metal hydroxide. In this specification, even if the thermoplastic resin does not have biodegradability alone, a resin that has been given biodegradability by an additive that promotes the depolymerization is defined as a thermoplastic resin having biodegradability. In one embodiment, a resin molded product containing a thermoplastic resin having biodegradability contains a thermoplastic resin that does not have biodegradability alone and an additive that promotes the depolymerization of the thermoplastic resin, and in another embodiment, it contains the polyolefin and a metal compound containing at least one selected from the group consisting of a metal salt, a metal oxide, and a metal hydroxide.

[0031] The resin molded body 1 may further contain a natural polymer compound. Examples of the natural polymer compound include polysaccharides. The natural polymer compounds may be used alone or in combination of two or more. Examples of the polysaccharides include cellulose, starch, chitosan, dextran, cellulose acetate, starch-modified resins, and cellulose-modified resins.

[0032] The resin molded body 1 may further contain a binder. The binder may be, for example, a processed food residue. Examples of processed food residue include compost made by fermenting and decomposing food residues discharged from households, or organic waste such as food processing waste, fish iliac bones, leftover food, and expired food discharged from food processing plants, supermarkets, restaurants, convenience stores, hotels, etc., with the action of microorganisms, and adjusting the salt concentration.

[0033] The resin molded body 1 described above contains a plant growth inhibitor and is therefore suitable for use as a resin molded body for plant growth inhibition. The resin molded body 1 is applied to soil 5 by inserting the pile body 3 into the soil 5 so that a part or the whole of the pile body 3 is buried in the soil 5, as shown in FIG. 1(b), for example. This allows the resin molded body 1 to be suitably held in a desired location in the soil 5, even if rain falls on the soil 5.

[0034] The pile-shaped resin molded body 1 is molded, for example, by injection molding. In injection molding, for example, a raw material containing a growth inhibitor and a resin is heated to a temperature at which the resin softens, the heated raw material is poured into a mold, and the resin is hardened by cooling for a certain period of time.

[0035] The resin molded body may have other embodiments. FIG. 2 is a perspective view showing a resin molded body according to another embodiment. As shown in FIG. 2, a resin molded body 11 according to another embodiment is molded into a granular shape. The resin molded body 11 may be, for example, an elliptical sphere as shown in FIG. 2, or may be another fixed shape such as a sphere, a cylinder, or an elliptical cylinder, or may be an irregular shape. By being molded into such a shape, the resin molded body 11 can be spread on soil 15 as shown in FIG. 2. The maximum length d3 of the resin molded body 11 may be, for example, 0.5 to 5.0 mm.

[0036] This resin molded body 11 is also preferably used as a resin molded body for inhibiting plant growth, and is applied to soil 15 by being sprayed on soil 15 as shown in Fig. 2. This resin molded body 11 can also be preferably retained in a desired location in soil 15, for example, even if rain falls on soil 15.

[0037] The granular resin molded body 11 is molded, for example, by resin pellet granulation. In the resin pellet granulation, for example, a raw material containing a growth inhibitor and a resin extruded from an extruder is granulated into pellets while being cooled with cooling water or after being cooled.

[0038] Fig. 3 is a perspective view showing a resin molded body according to another embodiment. As shown in Fig. 3(a), a resin molded body 21 according to another embodiment is molded into a sheet shape. Since the resin molded body 21 is molded into such a shape, it can be laid in soil 25 as shown in Fig. 3(b).

[0039] The resin molded body 21 has, for example, a substantially rectangular planar shape. The lengths d4 and d5 of each side of the rectangle (the maximum length in the main surface direction of the resin molded body 21) may be, for example, 0.5 to 50 m. The thickness d6 of the resin molded body 21 may be, for example, 7 to 100 μm.

[0040] This resin molded body 21 is also preferably used as a resin molded body for inhibiting plant growth, and is applied to soil 25 by being laid so that one main surface is in contact with soil 25, as shown in Fig. 3(b). Resin molded body 21 may be partially or entirely buried in soil 25. This resin molded body 21 can also be preferably retained in a desired location in soil 25, for example, even if rain falls on soil 25.

[0041] The sheet-like resin molded product may have voids (holes) penetrating through the sheet in the thickness direction, unevenness in the thickness direction of the sheet, etc. The sheet-like resin molded product may be, for example, in the form of a net having a mesh structure.

[0042] The sheet-like resin molded body 21 is molded, for example, by extrusion molding. In extrusion molding, for example, a raw material containing a growth inhibitor and a resin is melted and plasticized in an extruder, extruded from a die, cooled and solidified, and given a predetermined shape and dimensions.

[0043] One embodiment of the present invention may be a method for inhibiting plant growth. This method includes a step of applying the above-mentioned growth inhibitor or the above-mentioned resin molded body to soil. This makes it possible to inhibit the growth of plants present in the soil. The method of applying the growth inhibitor or the resin molded body in this step is appropriately selected depending on, for example, the state and shape of the growth inhibitor or the resin molded body. In this step, the growth inhibitor or the resin molded body may be inserted, spread, or laid in the soil.

[0044] In one embodiment, the application amount of the growth inhibitor or resin molded product is preferably 500 g or more, more preferably 1000 g or more per square meter of soil, from the viewpoint of more suitably inhibiting plant growth. The application amount of the growth inhibitor or resin molded product may be, for example, 2500 g or less per square meter of soil.

[0045] In another embodiment, the application amount of the growth inhibitor or resin molded product is such that the application amount of the above-mentioned active ingredient is preferably 0.01 g or more, more preferably 0.1 g or more, even more preferably 2.6 g or more, and particularly preferably 5.2 g or more per square meter of soil, from the viewpoint of more suitably suppressing plant growth. The application amount of the growth inhibitor or resin molded product may be, for example, such that the application amount of the above-mentioned active ingredient is 400 g or less, preferably 200 g or less, and more preferably 10.4 g or less per square meter of soil.

[0046] The plant to which the growth inhibitor or resin molded product is applied (to inhibit its growth) may be an annual plant or a perennial plant, preferably an annual plant. The plant may be a grass family or a non-grass family, preferably a grass family. The plant is particularly preferably an annual grass family plant.

[0047] The plants to which the growth inhibitor or resin molding is applied may be, for example, annual bluegrass, chickweed, polygonum, lamb's paw, dandelion, dayflower, crabgrass, Japanese knives, goosegrass, paspalum, purslane, amplexicaule, cornflower, mugwort, ragweed, nutsedge, green foxtail, wood sorrel, sedge, clover, rice bran, daisy, annual bluegrass, annual foxtail, rump, fleabane, clover, earwort, phillyraeoides, mugwort, common mugwort, sowberry, persimmon, barnyard millet, solidago altissima, komatsuna, shepherd's purse, or dog mustard. The above-mentioned resin molded article and the above-mentioned method are suitably used when the plants are weeds (annual plants and perennial plants).

[0048] One embodiment of the present invention may be soil 5, 15, 25 containing the resin molded body 1, 11, 21 of the plant as shown in Fig. 1(b), Fig. 2, and Fig. 3(b). The resin molded body may be present in the soil 5 as shown in Fig. 1(b), or may be present on the surface of the soil 15, 25 as shown in Fig. 2 and Fig. 3(b). By containing the resin molded body 1, 11, 21, the soil 5, 15, 25 becomes soil capable of suppressing plant growth. Therefore, the resin molded body 1, 11, 21 can also be said to be a resin molded body for soil modification capable of modifying soil to suppress plant growth. EXAMPLES

[0049] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0050] (Examples 1 to 3) The plant growth inhibitors shown in Table 1 were evaluated for their plant growth inhibitory effects by the Plant Regulator Research Association, a public interest incorporated foundation, using the evaluation method described below. That is, first, the diameter is 8 cm, the height is 9 cm, and the area is 0.005 m. 2Three pots (with five holes on the bottom) were prepared, and volcanic ash clay loam (pH: 5.8, humus content: 13.02%, maximum water capacity: 115%) was spread in the pots to a height of 6.5 cm from the bottom. Next, separately from the spread soil, the volcanic ash clay loam was disinfected with chloropicrin and dried, and then sieved with a mesh size of 2 to 4 mm to obtain disinfected and dried volcanic ash clay loam. The obtained disinfected and dried volcanic ash clay loam was spread on top of the volcanic ash clay loam spread in the pots to a height of 1.5 cm, and then about 3 cc of barnyard grass seeds were sown. The barnyard grass seeds were then covered with disinfected and dried volcanic ash clay loam, and a growth inhibitor was applied on top of that at 150 g / m. 2 The amount of the solution was applied to each pot. After 15 and 22 days, the number of germinated barnyard grass plants and their plant height were measured. After 30 days, the above-ground parts of the germinated barnyard grass plants were cut and the mass of the above-ground parts of the barnyard grass was measured. The average values ​​of the measurement results for the three pots are shown in Table 1.

[0051] Soybean oil containing a triester of a fatty acid and glycerin was used as the triester in Example 1. The fatty acids constituting the triester included palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid.

[0052] Comparative Example 3 The plant growth inhibitory effect was evaluated in the same manner as in Examples 1 to 3, except that no growth inhibitor was applied.

[0053] [Table 1]

[0054] From the evaluation results, comparing Example 1, in which a triester was used as a growth retarder, with Comparative Example 1, in which no growth retarder or comparative component was applied, in Example 1, the number of germinated plants after 15 days was 11, about one sixth of the number of germinated plants, and the number of germinated plants after 22 days was about the same, but the plant height was low both after 15 days and 22 days, and the mass after aboveground cutting was also low. Therefore, it can be said that the triester used in Example 1 can inhibit plant growth.

[0055] Comparing Example 2, in which glycerin was used as a growth retarder, with Comparative Example 1, in which no growth retarder or comparative component was applied, Example 2 showed smaller values ​​in all respects, including the number of sprouted plants and plant height after 15 and 22 days, and the mass of the aboveground part after cutting after 30 days. Therefore, it can be said that the glycerin used in Example 2 can inhibit plant growth.

[0056] Comparing Example 3, in which sorbitol was used as a growth retarder, with Comparative Example 1, in which no growth retarder or comparative component was applied, the plant height after 15 days was similar in Example 3, but the number of sprouted plants after 15 days, the plant height and number of sprouted plants after 22 days, and the mass of the aboveground part after cutting were smaller. Therefore, it can be said that sorbitol used in Example 3 can suppress plant growth.

[0057] In Examples 1 to 3, no withering of plants was observed, and it is clear that the growth inhibitor merely inhibits growth and is environmentally friendly. [Explanation of symbols]

[0058] 1, 11, 21...resin molding, 2...pile head, 3...pile body, 5, 15, 25...soil.

Claims

1. It consists only of triesters of carboxylic acids and glycerin, A plant growth inhibitor wherein said triester is derived from soybean oil, except where said triester is cottonseed oil.

2. A plant growth inhibitor which inhibits the growth of plants of the Gramineae family, comprising only glycerin, only sorbitol, or only glycerin and sorbitol.

3. 3. The plant growth inhibitor according to claim 2, which consists solely of said glycerin.

4. 3. The plant growth regulator according to claim 2, which consists essentially of sorbitol.

5. 3. The plant growth inhibitor according to claim 2, which consists essentially of said glycerin and said sorbitol.

6. A method for inhibiting plant growth, comprising applying the plant growth inhibitor according to any one of claims 1 to 5 to soil.

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