JP2020129985A - Production method of cupressaceae tree seedlings and production method of cupressaceae tree - Google Patents

Abstract

To provide a method for producing Cupressaceae tree seedlings, which secures a sufficient amount for use in forestry and obtains cored seedlings.SOLUTION: There is provided a production method of Cupressaceae tree seedlings, including that a main axis of Cupressaceae tree 1 in the juvenile phase is made into a bridge shape, a sprout branch 11 is generated from the bridge-shaped main axis, and the sprout branch 11 generated from the main axis is harvested so as to obtain cuttings.SELECTED DRAWING: Figure 3

Description

The present invention relates to a method for producing a sapling of a Cupressaceae tree using cuttings and a method for producing a cypressaceae tree using the sapling.

Cupressaceae trees such as Japanese cedar and Japanese cypress are widely used as high-value-added building materials. Therefore, it has been used as a forestry even if it takes a long period of about 40 to 60 years from planting to felling. However, in recent years, forestry that requires long-term forestry has become difficult due to price declines due to imports of foreign materials. Therefore, a new forestry industry that enhances profitability by growing early trees and increasing the number of fellings is desired.

As such an early-maturing tree, Chinese fir, a tree of the Cupressaceae family, has been proposed. Chinese fir seedlings are produced from seedlings or cuttings. By the way, Chinese fir is a conifer that is distributed from central to southern China, and came to Japan in the latter half of the Edo period and is planted in shrines and temples. Therefore, in order to produce seedlings from the seedlings of Chinese fir that exist in Japan, it is not possible to secure a sufficient amount for use as a forestry industry. Therefore, it has been studied to produce Chinese fir seedlings from cuttings (see, for example, Non-Patent Document 1).

Non-Patent Document 1 discloses that when a cored branch of a canopy, a branching branch, or a sprout branch generated after cutting a branch of the canopy is used as a cutting, the seedling is easily bent. If the seedlings are bent, trees that can be used as building materials cannot be obtained, which is unsuitable for forestry used as building materials. On the other hand, it is disclosed that when sprout branches generated from the ground are used for cuttings, seedlings are centered, that is, seedlings with straightness can be obtained.

Oita Prefectural Agriculture, Forestry and Fisheries Research Guidance Center Forestry Research Department, "Guide for short-cutting forestry using early-maturing trees (Chinese fir, Chanmodoki edition)", published in April 2015

The reality is that even if seedlings are produced using only sprout branches generated from the ground, a sufficient amount cannot be secured for use in forestry.
Therefore, a new method for producing seedlings that can secure a sufficient amount for use in forestry is desired.

An object of the present invention is to provide a method for producing a sapling of a Cupressaceae tree, which secures a sufficient amount for use in forestry and obtains a sapling having an excellent rooting rate and centering rate.

As a result of diligent studies on the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by using sprout branches generated from a bridge-shaped main shaft for cuttings, and have completed the present invention.
That is, the present inventors provide the following [1] to [6].
[1] Making the main shaft of a young Cupressaceae tree into a bridge shape, generating sprout branches from the bridge-shaped main shaft, and collecting the sprout branches generated from the main shaft to produce cuttings. How to produce saplings of Cupressaceae trees that have.
[2] The method for producing a seedling of a Cupressaceae tree according to the above [1], wherein the cuttings are further inserted into a bed, rooted and cultured, and then seedlings are raised.
[3] The sapling of the Cupressaceae tree according to the above [1] or [2], wherein the upper end of the main shaft is fixed on the same horizontal plane as the ground or at a position below the ground to form a bridge. Production method.
[4] The method for producing a sapling of a Cupressaceae tree according to any one of the above [1] to [3], wherein the Cupressaceae tree is a plant belonging to the genus Cunninghamia.
[5] The method for producing a sapling of a cypress family tree according to any one of the above [1] to [4], wherein the cypress family tree of the juvenile phase is 3 years or less (third year old) after sowing.
[6] A method for producing a Cupressaceae tree, which comprises growing a forest using the seedlings produced by the method for producing a seedling of a Cupressaceae tree according to any one of the above [1] to [5].

According to the present invention, it is provided a method for producing a sapling of a Cupressaceae tree, which can secure a sufficient amount for use in forestry and can obtain a sapling having an excellent rooting rate and centering rate. Can be done.

FIG. 1 is a schematic diagram of a Cupressaceae tree that generates sprout branches. FIG. 2 is a schematic view showing a state in which a Cupressaceae tree is formed into a bridge shape. FIG. 3 is a schematic view showing a state in which sprouting branches are generated from a bridge-shaped Cupressaceae tree. FIG. 4 is a schematic diagram showing a state in which seedlings are produced by raising seedlings of sprouted branches that have been picked. FIG. 5 is a schematic view showing a state in which the main axis of a Cupressaceae tree is cut. FIG. 6 is a schematic view showing a state in which a sprout branch is generated from the ground with the main axis cut.

[1. How to produce saplings of Cupressaceae trees]
The method for producing saplings of Cupressaceae trees of the present invention is to make the main shaft of a juvenile Cupressaceae tree into a bridge shape, to generate sprout branches from the bridge-shaped main shaft, and to generate sprout branches from the main shaft. It has to collect ears and obtain cuttings. Further, the method for producing seedlings of Cupressaceae trees of the present invention preferably further includes cuttings of cuttings, inserting them into a bed, rooting and culturing them, and then raising seedlings.
The juvenile Cupressaceae tree is a head-picking mother tree (hereinafter, the juvenile Cupressaceae tree is also simply referred to as "head-picking mother tree"). Examples of Cupressaceae trees include the genus Hinoki (Hinoki, Sawara, etc.), the genus Cedar (Cedar), and the genus Cunninghamia (Chinese fir). Of these, the genus Cunninghamia, which is an exotic tree, is preferable.
Hereinafter, the method for producing a sapling of a Cupressaceae tree of the present invention will be described in detail with reference to the drawings according to a preferred embodiment thereof.

FIG. 1 is a schematic diagram of a Cupressaceae tree that generates sprout branches. As shown in FIG. 1, a juvenile Cupressaceae tree 1 is prepared in order to obtain cuttings for producing seedlings by utilizing cutting growth. The juvenile Cupressaceae tree 1 is prepared in a container 3 such as a pot or pot containing soil. In addition, a plurality of leaves 2 are present on the main axis of the juvenile Cupressaceae tree 1. Then, buds are present at the roots of the plurality of leaves 2. When grown in a normal state as shown in FIG. 1, the growth of the buds existing at the roots of the plurality of leaves 2 is suppressed by the apical dominance, and sprouting branches are unlikely to occur.

The immature Cupressaceae tree 1 may be grown from seedlings or may be grown from cuttings. However, if the tree species does not allow multiple growth of cuttings, it must be grown from seedlings.
The Cupressaceae tree 1 has a bridge shape. Therefore, it is important that the Cupressaceae tree 1 is bent without being broken by human hands or the like before the main shaft (main stem) becomes woody. Therefore, it needs to be childish. The definition of immaturity depends on the tree species. For example, when the Cupressaceae tree 1 belongs to the genus Cunninghamia, it means 5 years or less after sowing (5 years old) or less, and preferably 3 years or less after sowing (3 years old) or less.

The conditions for growing a head-picking mother tree from seedlings differ depending on the tree species. The case where the Cupressaceae tree 1 belongs to the genus Cunninghamia is illustrated below. Fertilization is usually applied when growing a mother tree from seedlings. When fertilizer is applied, the fertilizer is not particularly limited, and a fast-acting fertilizer or a slow-acting fertilizer may be used. The fertilizer is preferably an inorganic fertilizer or an organic fertilizer, and more preferably a chemical fertilizer.

The components contained in the fertilizer are not particularly limited, and examples thereof include components that can be a source of plant nutrients such as inorganic components, silver ions, antioxidants, carbon sources, vitamins, amino acids, and plant hormones.
The form of fertilizer is also not particularly limited. For example, it may be either a solid substance (powder, granule, etc.) or a liquid (liquid fertilizer, etc.).

Examples of the inorganic component include elements such as nitrogen, phosphorus, potassium, sulfur, calcium, magnesium, iron, manganese, zinc, boron, molybdenum, chlorine, iodine and cobalt, and inorganic salts containing these elements. Examples of the inorganic salt include potassium nitrate, ammonium nitrate, ammonium chloride, sodium nitrate, potassium monohydrogen phosphate, sodium dihydrogen phosphate, potassium chloride, potassium sulfate, ammonium sulfate, magnesium sulfate, ferrous sulfate, and ferric sulfate. , Manganese sulfate, zinc sulfate, copper sulfate, sodium sulfate, calcium chloride, magnesium chloride, boric acid, molybdenum trioxide, sodium molybdate, potassium nitrate, cobalt chloride and the like, and hydrates thereof.

Examples of the antioxidant include ascorbic acid and sulfites. Since ascorbic acid has low persistence in the medium, environmental pollution can be suppressed. Therefore, ascorbic acid is preferable as the antioxidant.

Examples of the carbon source include carbohydrates such as sucrose and derivatives thereof; organic acids such as fatty acids; and compounds such as primary alcohols such as ethanol.

Examples of vitamins include biotin, thiamine (vitamin B1), pyridoxine (vitamin B4), pyridoxal, pyridoxamine, calcium pantothenate, inositol, nicotinic acid, nicotinic acid amide, and riboflavin (vitamin B2).

Examples of amino acids include glycine, alanine, glutamic acid, cysteine, phenylalanine, and lysine.

The fertilizer application method is not particularly limited, and the fertilizer application conditions may be suitable for the fertilizer to be used. For example, a method of spraying, applying, or spraying an appropriate amount of fertilizer on the support of the earing mother tree and / or the earing mother tree can be mentioned. Fertilization should be performed at least once and twice or more during the year prior to the scheduled ear collection date (when ear collection was performed in the previous year, usually between the previous year's ear collection and the scheduled ear collection date). Is preferable. The fertilization method may be different or the same depending on the number of fertilizations.

The support for the growth of the head-picking mother tree may be one that is usually used for the growth of plants. For example, natural soil such as sand and soil (eg, Akadama soil, Kanuma soil) can be mentioned. Other examples of supports include artificial soils such as paddy husk charcoal, coconut fiber, vermiculite, perlite, peat moss, glass beads; porous moldings such as foamed phenolic resin, rock wool; solidifying agents (eg, agar or gellan gum). ). At least one selected from another example of the support may be replaced with or used with natural soil. The support may be stored in a container. As the container, a conventional container may be used.

Other conditions for the growth of the head-picking mother tree (eg, temperature, humidity, light) can be appropriately set depending on the tree species. For example, it may be in natural conditions or may be artificially controlled. Examples of the temperature control condition include a daytime temperature of 15 to 35 ° C. (preferably 20 to 35 ° C.) and a nighttime temperature of 5 to 25 ° C. (preferably 10 to 25 ° C.). The habitat is not particularly limited, and may be either a closed space (eg, in a vinyl house, an artificial solar room, a greenhouse, indoors) or an open space (eg, outdoors). If necessary, a treatment for promoting growth (for example, root cutting) may be performed.

FIG. 2 is a schematic view showing a state in which a Cupressaceae tree is formed into a bridge shape. The prepared juvenile Cupressaceae tree 1 is formed into a bridge shape as shown in FIG. The upper end of the main shaft of the Cupressaceae tree 1 is preferably fixed on the same horizontal plane as the ground or at a position below the ground. When the Cupressaceae tree 1 grows in a bridge shape, the apical dominance is broken and sprout branches are generated from the buds existing at the roots of a plurality of leaves. It is preferable to cut off about 1 cm at the tip of the spindle.

The fixing member 5 for fixing the upper end of the main shaft of the Cupressaceae tree 1 is not particularly limited, and examples thereof include a pole and the like. Further, the fixing tool 4 for fixing the upper end portion of the main shaft of the Cupressaceae tree 1 to the fixing member 5 is not particularly limited, and examples thereof include a clip, a string, rubber, and a binding band.

FIG. 3 is a schematic view showing a state in which a sprout branch 11 is generated from a bridge-shaped cypress family tree 1. When grown in the state of FIG. 2, as shown in FIG. 3, sprouting branches 11 are generated from the buds at the roots of a plurality of leaves 2 existing on the main axis of the Cupressaceae tree 1. Here, a plurality of sprout branches occur as shown in FIG.
The conditions for generating the sprout branch 11 from the bridge-shaped Cupressaceae tree 1 differ depending on the tree species. For example, there are conditions for the growth of the ear-picking mother tree. The conditions for generating the sprout branch 11 from the bridge-shaped Cupressaceae tree 1 may be the same as the conditions for the growth of the ear-picking mother tree, or may be partially changed.

After the sprout branch 11 generated from the main axis of the Cupressaceae tree 1 grows, the head is collected to obtain cuttings. As described above, since there are a plurality of sprout branches, a plurality of cuttings can be obtained. At this time, a plurality of cuttings can be obtained from one sprout branch according to the size of the ear to be collected. Therefore, since a large number of cuttings can be obtained according to the number of sprout branches and the size of the cuttings, a sufficient amount can be secured for use in forestry.
The size of the cuttings to be collected is preferably 20 cm or less, more preferably 15 cm or less, and even more preferably 10 cm or less. The lower limit is not particularly limited, but is usually 1 cm or more, preferably 2 cm or more, more preferably 3 cm or more, still more preferably 4 cm or more, still more preferably 5 cm or more.
In the present invention, even a small-sized cutting can exhibit a good rooting rate. The leaves at the base of the cuttings (the side to be inserted into the support, for example, about 3 cm from the tip of the base) may be cut with a cutting tool such as scissors.

The scheduled ear collection date is not particularly limited. When the Cupressaceae tree belongs to the genus Cunninghamia, February-October is preferable, and March-September is more preferable. When the head-picking mother tree is produced as seedlings, it is more preferable to set the head-picking date within the above range. The actual head-picking date may be any day between 10 days before and after the scheduled head-picking date, and the day of the scheduled head-picking date is preferable.

In the method for producing a sapling of a Cupressaceae tree of the present invention, it is preferable to grow by changing the direction of the bridge of the heading mother tree after obtaining cuttings. When the bridge was grown in a different direction, the apical dominance of the newly upward bud was broken among the buds that did not have buds that existed at the bases of multiple leaves, and buds were generated. obtain. Therefore, it is possible to generate sprout branches multiple times from one heading mother tree to further secure cuttings that can be used as forestry.

FIG. 4 is a schematic diagram showing a state in which seedlings are produced by raising seedlings of sprouted branches that have been picked. As shown in FIG. 4, the seedlings of the Cupressaceae tree 1 can be produced by cutting the sprouted branches 11 as cuttings, inserting them into the bed 13 for rooting culture, and then raising seedlings. Although only one seedling is shown in FIG. 4, it goes without saying that in the method for producing a seedling of a Cupressaceae tree of the present invention, as many seedlings as the number of obtained cuttings can be produced. ..

Rooting from cuttings may be performed by a conventional method. For example, there is a method of rooting by inserting cuttings into a support. The support may contain additives that are used as needed. It may also be stored in a culture vessel. The cutting time may be at the same time as the ear collection, or at an appropriate time after the ear collection (for example, within 6 months, 5 months, 4 months, 3 months, or 2 from the ear collection). It may be within a month). Above all, it is preferable to collect the ears at the same time.
When the cutting is performed at an appropriate time after the ear collection, it is preferable to refrigerate the cutting (for example, 4 ° C. or lower) until the cutting. As a result, the rooting ability of the cuttings can be maintained.

The support may support (retain) the cuttings and the medium. Among them, a conventional support that has water absorption and breathability and can efficiently absorb the additive into the cutting can be used. The example of the support is the same as the example of the support that can be used when growing the heading mother tree, and is preferably a combination of natural soil and artificial soil. As the natural soil, Akadama soil or Kanuma soil is preferable. As the artificial soil, peat moss, coconut fiber, perlite or vermiculite are preferable.

Examples of the medium include known media for culturing plant tissues and aqueous solvents (eg, water). Among them, an aqueous solvent is preferable, and water is more preferable. Examples of the medium for culturing plant tissues include MS medium, Rinsemeyer skoog medium, white medium, Gambog B-5 medium, and niche niche medium. Of these, MS medium and Ganborg's B-5 medium are preferable. These media can be appropriately diluted and used as needed.
The medium may be either a liquid medium or a solid medium. However, the liquid medium is preferable in terms of work efficiency and less damage to the roots during transplantation. The liquid medium can be used as it is by mixing and preparing the medium composition. The solid medium can be used by mixing and preparing the medium composition in the same manner as the liquid medium, or after the preparation, solidifying with a solidifying agent (eg, agar, gellan gum).
The amount of the solidifying agent added can be appropriately set depending on conditions such as the type of solidifying agent and the composition of the medium. The amount of agar added to the medium is preferably 0.5 to 1% by weight. The amount of gellan gum added to the medium is preferably 0.2 to 0.3% by weight.

The additive may be any additive used at the time of rooting of cuttings. For example, fertilizers (eg, inorganic components, silver ions, antioxidants, carbon sources, vitamins, amino acids, plant hormones), rooting promoters other than the above (eg, International Publication No. 2011/136285, JP. Agents described in documents such as 2012-232907, 2013-95664, etc.) and the like.
The form of each component is not particularly limited, and may be either a solid (eg, powder, granule) or a liquid (eg, liquid fertilizer). In addition, the components constituting the additive may be mixed, absorbed or sprayed on the support, or may be directly sprayed, applied or sprayed on at least a part of the cuttings.

The additives may be mixed or at least partly separately contained in the support, or added to a known medium or aqueous solvent (eg, water) for plant tissue culture to the support. It may be included or applied directly to the cuttings (preferably the base).

The inorganic component may be one kind alone or a combination of two or more kinds. The example of the inorganic component is the same as the example of the inorganic component of the fertilizer of the ear-picking mother tree. Among them, the inorganic component preferably contains at least one selected from nitrogen, phosphorus, potassium, an inorganic salt containing nitrogen, an inorganic salt containing phosphorus, and an inorganic salt containing potassium.
When one kind of inorganic component is contained in the above-mentioned known medium, the amount in the medium is preferably 0.1 μM to 100 mM, more preferably 1 μM to 100 mM. In the case of a combination of two or more, the amount in each medium is preferably 0.1 μM to 100 mM, more preferably 1 μM to 100 mM.

The silver ion may be one kind alone or a combination of two or more kinds. Examples of silver ions include silver compounds (silver ion source) such as silver thiosulfate (STS, AgS ₄ O ₆ ) and silver nitrate. Among them, STS is preferable as the silver ion. It is presumed that STS takes the form of silver thiosulfate ion in the medium and is negatively charged. Therefore, it can contribute to the promotion of rooting and elongation of healthy roots. When silver ions are contained in the above-mentioned medium, the amount of the silver ion source in the medium is preferably 0.5 μM to 6 μM, more preferably 2 μM to 6 μM.

The antioxidant may be used alone or in combination of two or more. Examples of antioxidants are similar to those of fertilizers in the earstock mother tree. When the antioxidant is contained in the medium, the amount thereof is preferably 5 mg / l to 200 mg / l, more preferably 20 mg / l to 100 mg / l.

The carbon source may be one type alone or a combination of two or more types. The example of carbon source is similar to the example of carbon source of fertilizer of heading mother tree. When the carbon source is contained in the medium, the amount thereof is preferably 1 g / l to 100 g / l, more preferably 10 g / l to 100 g / l.
When the rooting culture is performed by supplying carbon dioxide gas, the rooting medium does not have to contain a carbon source, and preferably does not contain it. Since organic compounds that can be a carbon source such as sucrose also serve as a carbon source for microorganisms, it is necessary to cultivate them in a sterile environment when using a rooting medium to which these are added. However, by supplying carbon dioxide gas and performing rooting culture, the addition of a carbon source to the rooting medium can be omitted, and cultivation in a non-sterile environment becomes possible.

The vitamins may be used alone or in combination of two or more. Examples of vitamins are similar to those of vitamins in fertilizers of heading mother trees.
When one vitamin is added to the above-mentioned medium, the amount thereof is preferably 0.01 mg / l to 200 mg / l, more preferably 0.02 mg / l to 100 mg / l. When two or more combinations are added, the respective amounts are preferably 0.01 mg / l to 150 mg / l, more preferably 0.02 mg / l to 100 mg / l.

Amino acids may be used alone or in combination of two or more. Examples of amino acids are similar to those of amino acids in fertilizers of ear-picking mother trees.
When one kind of amino acid is added to the above-mentioned medium, the amount thereof is preferably 0.1 mg / l to 1000 mg / l. When two or more combinations are added, the amount in each medium is preferably 0.2 mg / l to 1000 mg / l.

Examples of plant hormones include rooting promoters such as auxin and cytokinin. The plant hormone may be one kind alone or a combination of two or more kinds. Of these, it is preferable to include auxin or a combination of auxin and cytokinin.
Examples of the auxin include naphthalene acetic acid (NAA), indoleacetic acid (IAA), p-chlorophenoxyacetic acid, 2,4-dichlorophenoxyacetic acid (2,4D), indolebutyric acid (IBA) and derivatives thereof. .. The auxin may be one of these or a combination of two or more.
Examples of cytokinins include benzyladenine (BA), kinetin, zeatin and derivatives thereof. Cytokinin may be one of these or a combination of two or more.
When one type of plant hormone is added to a medium, the amount thereof is preferably 0.001 mg / l to 10 mg / l, more preferably 0.01 mg / l to 10 mg / l. When two or more combinations are added, the respective amounts are preferably 0.001 mg / l to 10 mg / l, more preferably 0.01 mg / l to 10 mg / l.

The method of adding the plant hormone may follow the instruction manual of a commercially available product. For example, a method of directly applying a plant hormone powder (for example, auxin) to the base of the cutting (preferably a base to which a physical stimulus is applied) before insertion, or a method of adding to the support can be mentioned.

The timing of addition of the rooting medium is not particularly limited. For example, at the start of rooting culture, during the culture. The method of addition depends on the mode of the component, and examples thereof include spraying, wetting, and spraying.
The number of additions is not particularly limited, and may be added only once (at the start of culturing) or twice or more (at the start and in the middle of culturing). In addition, the components constituting the rooting medium may be added together, may be added separately, or may be replaced or replenished as appropriate during the process.

By storing the support in the culture container, it is possible to smoothly raise seedlings of cuttings after rooting. The culture vessel preferably has a water passage (net, pores). As a result, it can be used for bottom irrigation. For example, containers (eg, containers described in JP-A-2017-079706, multi-cavity containers (JFA-150, JFA-300), etc.), cell trays, nursery pots, planters, and bats (net-like on the bottom or side). A box-shaped container having an opening). It may be a type of culture container in which one plant of cuttings is planted in one container, or a type of culture container in which two or more plants of cuttings are planted in one container. The material of the culture container is not particularly limited, and examples thereof include resin, glass, and wood.

The cuttings to be inserted into the support may be appropriately selected depending on the conditions such as the type of the support, the environment, and the type of the cuttings. For example, a method of inserting a part including the base of the cutting (for example, 1 cm to 5 cm from the base) into the support can be mentioned.
The base of the cutting means the region at one end of the cutting where the root is formed (opposite to the end where the leaf is formed). The base of the polyblast is the region having the cut surface when the polyblast is divided.
At the time of insertion, physical stimulation to the cuttings may be applied (eg, the base is scratched). Thereby, the rooting rate can be improved. The size (eg, size, shape) of the scratch on the base is not particularly limited. For example, a cross-shaped wound can be made on the base of the multi-bud (the cut surface described above), which is a cutting. Examples of the tool for scratching include scissors and a knife. It is preferable that the leaves of the base of the cuttings to be inserted into the support are excised.

As the irrigation method at the time of rooting, for example, either overhead irrigation or bottom irrigation may be used. Above all, bottom irrigation is preferable. Examples of the bottom irrigation method include a method of immersing a culture container (providing a water passage) containing a support into which cuttings are inserted in water.
The amount of irrigation is not particularly limited as long as the cuttings are substantially moistened. In the rooting culture step, the cuttings may be irrigated via a water-absorbing member. That is, water is supplied to the water-absorbent member, and water is supplied to the cuttings through the portion where the medium and the water-absorbent member are in contact with each other. It is preferable that water is supplied to the water-absorbent member so that the medium is moistened and / or the water-absorbent member is in a state of uniformly absorbing water. As a result, the water environment of the medium can be maintained appropriately, constantly and uniformly. The irrigation operation may be performed by either manual irrigation or an automatic irrigation system.

The rooting culture period for rooting the cuttings also differs depending on the tree species. However, it may be continued until at least rooting is observed, and it is preferable to continue until the roots are full. It is usually 2 weeks to 10 months, preferably 4 weeks to 8 months, more preferably 1 to 6 months.

Conditions for rooting other than the above (eg, temperature, light, carbon dioxide concentration, humidity) can be appropriately determined depending on the tree species, site, size, type of additive, etc. of the cuttings. For example, in the case of the genus Cunninghamia, it is as follows.
The temperature is more preferably 23 to 28 ° C.
The light radiated to the cuttings may be natural light or light whose light intensity is artificially adjusted. Examples of the artificial adjustment method include adjustment of light intensity, adjustment of wavelength component, and shading.
Light intensity (photosynthetic photon flux density) is preferably ^{10μmol / m 2 / s~1000μmol / m} 2 / s, 50μmol / m 2 / s~500μmol / m 2 / s is more preferable.
The light to be irradiated is preferably light containing a wavelength component of 650 nm to 670 nm and a wavelength component of 450 nm to 470 nm, and the ratio of the two is preferably 9: 1 to 7: 3, and more preferably 9: 1 to 8: 2. Is.
When shading, the shading rate is preferably 30 to 70%, more preferably 40 to 60%.

The carbon dioxide concentration at the time of rooting is usually 300 to 2000 ppm, preferably 800 to 1500 ppm. The carbon dioxide concentration can be adjusted to the above range by using a culture vessel equipped with a carbon dioxide permeable membrane (for example, placed in equipment such as an artificial meteorological instrument). Be done.

The humidity is preferably 60% or more, more preferably 80% or more. This can promote rooting from plants. There is no particular upper limit.
The culture vessel is preferably installed in a plastic greenhouse. This can facilitate control of conditions such as humidity and temperature.

In the present invention, seedlings are raised after rooting the cuttings. Seedlings may be raised by transplanting from the culture container to a seedling raising container, a nursery field (soil: for example, the above-mentioned natural soil), or as it is in the culture container.

The fertilizer application method is not particularly limited, and the fertilizer application conditions (fertilizer application interval, fertilizer application amount, fertilizer application method) suitable for the fertilizer to be used may be used. The example of fertilizer component is the same as the example of fertilizer given to the heading mother tree.

Conditions for raising seedlings (eg, temperature, humidity, light irradiation, irradiation conditions) can be appropriately determined. The conditions may be the same as those for rooting culture, or may be different. When the seedlings grow to a certain extent (for example, 30 cm or more or 35 cm or more), seedlings used for afforestation or the like can be obtained.

The advantages of the method for producing saplings of Cupressaceae trees of the present invention are as follows. As shown in FIG. 3, a plurality of sprout branches 11 can be generated from the main axis of one Cupressaceae tree 1. Then, all of the generated plurality of sprout branches 11 can be used as cuttings. Therefore, a plurality of cuttings can be prepared from the main shaft of one Cupressaceae tree 1, and a sufficient amount of seedlings to be used for forestry can be secured.

On the other hand, it will be explained with reference to the drawings that the conventionally known method has a problem that it is difficult to secure a sufficient amount of seedlings for use in forestry.
As described above, it is known that seedlings are easily bent when the cored branches of the canopy, the branching branches, and the sprout branches generated after cutting the branches of the canopy are used for cuttings. Therefore, it is necessary to use sprout branches generated from the ground for cuttings.

Even in the conventional method of using sprout branches generated from the ground for cuttings, a juvenile Cupressaceae tree 1 is first prepared. Regarding the preparation of the Cupressaceae tree 1, the same can be said as described above in the method for producing the seedlings of the Cupressaceae tree of the present invention.

FIG. 5 is a schematic view showing a state in which the main axis of the Cupressaceae tree 1 is cut. When saplings are produced by using sprout branches generated from the ground as cuttings, the main shaft is cut to an appropriate length m instead of bridging the stems. Cutting can be performed using known tools such as debranching scissors and nippers.
The appropriate length m differs depending on the tree species. When the Cupressaceae tree 1 belongs to the genus Cunninghamia, it means that its size is 10 to 30 cm.

FIG. 6 is a schematic view showing a state in which a plurality of sprout branches 21 are generated from the ground with the main axis cut. When grown in the state of FIG. 5, as shown in FIG. 6, a plurality of sprout branches 21 are generated from the ground. At this time, a plurality of sprout branches 31 are also generated from the buds at the roots of the plurality of leaves 2 existing on the main axis of the Cupressaceae tree 1.
The conditions for growing the Cupressaceae tree 1 with the main axis cut can be appropriately set. For example, it may be in natural conditions or may be artificially restricted. Examples of the temperature control condition include a daytime temperature of 15 to 35 ° C. (preferably 20 to 35 ° C.) and a nighttime temperature of 5 to 20 ° C. (preferably 10 to 20 ° C.). The habitat is not particularly limited, and may be either a closed space (eg, in a vinyl house, an artificial solar room, a greenhouse, indoors) or an open space (eg, outdoors).

According to the conventional method, the sprout branch 21 generated from the ground and the sprout branch 31 generated from the root buds of the plurality of leaves 2 of the stem can be obtained. However, when sprout branches 31 generated from the root buds of a plurality of leaves 2 of the stem are used for cuttings, the seedlings may bend.
Therefore, it is necessary to utilize the sprout branch 21 generated from the ground. However, the number of sprout branches 21 generated from the ground is limited, and it is difficult to secure a sufficient amount of seedlings for use in forestry.

[2. Production method of Cupressaceae trees]
The method for producing a Cupressaceae tree of the present invention includes a step of growing a forest using the seedlings produced by the method for producing a seedling of a Cupressaceae tree of the present invention.
As described above, according to the method for producing saplings of Cupressaceae trees of the present invention, a plurality of cuttings (sprouting branches) can be obtained from one main shaft, so that a large amount of saplings can be produced. That is, a sufficient amount of seedlings can be secured for use in forestry. In addition, the seedlings produced by the method for producing seedlings of Cupressaceae trees of the present invention tend to be centered in the process of raising seedlings. Therefore, when a Cupressaceae tree is produced using the seedling, a large amount of a Cupressaceae tree suitable for a building material can be produced.
Therefore, the method for producing Cupressaceae trees of the present invention can be expected as a new forestry industry that enhances profitability by growing early-maturing trees and increasing the number of ears.

The process of growing seedlings is not particularly limited. For example, saplings that have grown to some extent are carried to a forest area and planted. The forest area can be changed as appropriate depending on the tree species. When planting seedlings, a tree shelter or the like may be used from the viewpoint of preventing feeding damage to wild rabbits and the like.

Hereinafter, the present invention will be described in detail with reference to Examples. The following examples are for the purpose of preferably explaining the present invention, and do not limit the present invention.

[Rooting rate]: The cuttings were inserted into the prepared cutting bed, grown in a normal glass greenhouse for 2 months, then dug up from the cell tray, and the number of rooted cuttings was inserted into the cutting bed. Calculated by dividing by the number of ears.

[Centering rate]: After transplanting the rooted and cultured cuttings into a container, seedlings were raised in a normal glass greenhouse. It was calculated by dividing the number confirmed to be cored after one month by the number of seedlings raised.

(Example 1: Main shaft prone)
About 1 cm of the tip of the main shaft was cut off on June 18, 2018 for potted seedlings of seedlings 2 years after sowing of Chinese fir (2nd year of age), and the main shaft was turned down to make a heading mother tree. Here, "turning down the main shaft" means bending the main shaft of Chinese fir in a bridge shape in a horizontal direction with the ground and fixing it so that the tip of the main shaft is below the soil surface of the potted plant. When two months had passed since the main shaft was laid down, 62 sprout branches generated from the main shaft were collected, and leaves in a range of about 2 to 3 cm below were removed to obtain 62 cuttings.

A cell tray was used as the culture container. Akatama small grain soil (manufactured by Yasushima Shoji Co., Ltd.) and peat moss (manufactured by Toho Co., Ltd.) were mixed 1: 1 and filled in a cell tray to prepare a bed. After applying 5 to 10 mg of Luton (registered trademark) powder (manufactured by Ishihara Bioscience, white powder containing plant hormone NAA, concentration of NAA is 0.4%) to the bases of the 62 cuttings obtained above. , The cuttings were inserted from the base to a position of 1.5 to 2.5 cm and inserted into the bed to perform rooting culture. Rooting culture was carried out from August to October in a normal glass greenhouse. Two months later, it was dug up from the cell tray and the rooting rate was evaluated. The rooted and cultured cuttings (59) were transplanted into a container having a capacity of 300 cc. After transplanting to a container, seedlings were raised in a normal glass greenhouse, and the number of seedlings that had cored was 53.
Table 1 shows the evaluation results of the number of sprouted branches, rooting rate, number of seedlings with core, and cored rate.

(Comparative example 1: Head shaft switching back)
Regarding the potted planting of seedlings 2 years after sowing of Chinese fir (2nd year of age), on June 18, 2018, the main axis was cut back about 5 cm from the ground to make a heading mother tree. When two months had passed since the main shaft was cut back at about 5 cm from the ground, 33 sprout branches generated from the ground were collected and 33 cuttings were obtained.
The obtained 33 cuttings were inserted into a cutting bed prepared in the same manner as in Example 1 for rooting culture. Rooting culture was carried out from August to October in a normal glass greenhouse. Two months later, it was dug up from the cell tray and the rooting rate was evaluated. The rooted and cultured cuttings (31) were transplanted into a container having a capacity of 300 cc. After transplanting to a container, seedlings were raised in a normal glass greenhouse, and the number of seedlings that had cored was 30.
Table 1 shows the evaluation results of the number of sprouted branches, rooting rate, number of seedlings with core, and cored rate.

(Comparative example 2: No processing)
For potted plants of Chinese fir seedlings, 10 cuttings naturally generated from the ground were obtained.
The obtained 10 cuttings were inserted into a cutting bed prepared in the same manner as in Example 1 for rooting culture. Rooting culture was carried out from August to October in a normal glass greenhouse. Two months later, it was dug up from the cell tray and the rooting rate was evaluated. The rooted and cultured cuttings (9) were transplanted into a container having a capacity of 300 cc. After transplanting to a container, seedlings were raised in a normal glass greenhouse, and the number of seedlings that had cored was eight.
Table 1 shows the evaluation results of the number of sprouted branches, rooting rate, number of seedlings with core, and cored rate.

Table 1 shows the treatment methods of Example 1 and Comparative Examples 1 and 2, the number of sprouted branches, the rooting rate, the number of seedlings centered, and the centering rate.

As can be seen from Table 1, according to the method for producing saplings of Cupressaceae trees of the present invention, the amount of saplings produced is improved as compared with the conventional method, and the saplings having excellent rooting rate and centering rate are produced. Obtainable.

1, 11, 21, 31: Cupressaceae trees 2, 12, 22, 32: Leaves 3, 13: Containers 4: Fixtures 5, Fixing members, l: Horizontal plane, m: Length.

Claims (6)

Making the main axis of the cypress family tree of the juvenile phase bridge-shaped,
A method for producing a sapling of a Cupressaceae tree, which comprises generating sprout branches from the bridge-shaped main shaft and collecting the sprout branches generated from the main shaft to obtain cuttings. The method for producing a seedling of a Cupressaceae tree according to claim 1, wherein the cuttings are inserted into a bed, rooted and cultured, and then seedlings are raised. The method for producing a sapling of a Cupressaceae tree according to claim 1 or 2, wherein the upper end of the main shaft is fixed on the same horizontal plane as the ground or at a position below the ground to form a bridge. The method for producing a sapling of a Cupressaceae tree according to any one of claims 1 to 3, wherein the Cupressaceae tree is a plant belonging to the genus Cunninghamia. The method for producing a sapling of a cypress family tree according to any one of claims 1 to 4, wherein the cypress family tree of the juvenile phase is 3 years or less after sowing. A method for producing a Cupressaceae tree, which comprises growing a forest using the seedlings produced by the method for producing a sapling of a Cupressaceae tree according to any one of claims 1 to 5.

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