JP2016136904A - Method for evaluating light intensity suitable for rooting - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique capable of simply specifying an optimum rooting and culture condition corresponding to a condition such as a type or the like of plant, and improving a rooting rate of a seedling, the number and the length of roots that started to grow.SOLUTION: The present invention is a rooting method of a scion or a cultured product of a plant in which at least a part of a plant is irradiated with light, and quantum yield (1) of a photochemical system II when saturated light having light intensity 7,000 μmol/m/s or more is irradiated and/or quantum yield (2) of a photochemical system II when saturated light of light intensity 15,000 μmol/m/s is irradiated are measured, light intensity in which a measured value of the quantum yield (1) is 0.60 to 0.80 and/or a measured value of the quantum yield (2) is 0.20 to 0.42 is specified, and roots of a scion or a cultured product of a plant is started to grow at specified light intensity.SELECTED DRAWING: None

Description

  The present invention relates to a method for evaluating light intensity suitable for rooting of cuttings, cultures and the like.

  Conventionally, a method using photoautotrophic culture is known as a method for rooting cuttings. For example, in Patent Document 1, a rooting bed wetted with a liquid medium containing nitrogen, phosphorus, and potassium as essential elements and not containing a carbon source is prepared in a culture container, and then inserted into this to press the ears and cultured. In addition, a method is described in which rooting from the cutting head is performed while controlling the carbon dioxide gas concentration in the culture vessel.

JP 2001-186814 A

  In the technique of Patent Document 1, rooting culture is performed in a certain environment. However, optimal rooting culture conditions differ depending on conditions such as the type of plant and the like, and Patent Document 1 does not describe means for optimizing rooting culture conditions.

  The present invention provides a technique capable of easily specifying optimal rooting culture conditions according to conditions such as the type of plant and improving the rooting rate of seedlings, the number of roots and the length of roots. For the purpose.

  The present inventors have intensively studied to solve the above problems. As a result, it has been found that there is a relationship between the light intensity at which the photon yield of the photosystem II is in a certain range, the rooting rate, and the number and length of roots rooted. Reached.

The present invention provides the following [1] to [5].
[1] At least a part of the plant is irradiated with light, and saturated light having a light intensity of 7,000 μmol / m ² / s or more is irradiated with photosystem II photon yield (1) and / or light Measuring the photon yield (2) of photosystem II when irradiated with saturated light having an intensity of 15,000 μmol / m ² / s;
Specifying the light intensity where the measured value of the photon yield (1) is 0.60 to 0.80 and / or the measured value of the photon yield (2) is 0.20 to 0.42. including,
A method for evaluating light intensity suitable for rooting of a plant cutting or a culture.
[2] The method for evaluating light intensity according to [1], wherein the plant is a cherry genus plant, a eucalyptus plant, a genus plant, a porcupine genus plant, or a pine genus plant.
[3] The emergence of plant cuttings or culture, comprising irradiating light of the light intensity specified by the method according to [1] or [2] to root the plant cuttings or culture. Root method.
[4] A method for producing a cutting plant seedling of a plant, wherein the cutting of the plant or the culture is rooted by irradiating light having the light intensity specified by the method according to [1] or [2].
[5] A method for cultivating a plant, comprising irradiating light having a light intensity specified by the method according to [1] or [2] to root a cutting or a culture of the plant.

  According to the present invention, since the optimal rooting culture conditions according to conditions such as the type of plant can be easily and objectively specified in advance, the rooting rate in seedlings is increased, and the number of roots is large and the length is ensured. It is possible to improve the productivity and quality of seedlings and shorten the culture period.

1 is a graph showing the relationship between the photon yield (1) of Yoshino photosystem II and the light intensity in Example 1. FIG. FIG. 2 is a graph showing the relationship between the photon yield (1) and the light intensity of Yoshino photosystem II in Example 1. FIG. 3 is a graph showing the relationship between the light intensity and the rooting rate of Yoshino cherry cuttings in Example 1. FIG. 4 is a graph showing the relationship between the light intensity in Example 1 and the number of roots rooted from the insert of Yoshino cherry. FIG. 5 is a graph showing the relationship between the light intensity in Example 1 and the length of roots rooted from Yoshino cherry. 6 is a graph showing the relationship between the photon yield (2) of photosystem II of round leaf eucalyptus and the light intensity in Example 2. FIG. 7 is a graph showing the relationship between the photon yield (2) of photosystem II of round leaf eucalyptus and the light intensity in Example 2. FIG. FIG. 8 is a graph showing the relationship between the light intensity in Example 2 and the rooting rate of the culture of round leaf eucalyptus. FIG. 9 is a graph showing the relationship between the light intensity in Example 2 and the number of roots rooted from the culture of round leaf eucalyptus. FIG. 10 is a graph showing the relationship between the light intensity in Example 2 and the length of roots rooted from a culture of round leaf eucalyptus. FIG. 11 is a graph showing the relationship between the photon yield (2) of Mao's photosystem II in Example 3 and the light intensity. FIG. 12 is a graph showing the relationship between the photon yield (2) of Mao's photosystem II in Example 3 and the light intensity. FIG. 13 is a graph showing the relationship between the light intensity in Example 3 and the rooting rate of the mao culture. FIG. 14 is a graph showing the relationship between the light intensity in Example 3 and the number of roots rooted from the mao culture. FIG. 15 is a graph showing the relationship between the light intensity in Example 3 and the length of roots rooted from the mao culture. FIG. 16 is a graph showing the relationship between the photon yield (2) of the photosystem II of Porcupine in Example 4 and the light intensity. FIG. 17 is a graph showing the relationship between the light intensity and the rooting rate of a porcupine culture in Example 4. FIG. 18 is a graph showing the relationship between the light intensity in Example 4 and the number of roots rooted from the porcupine culture. FIG. 19 is a graph showing the relationship between the light intensity in Example 4 and the length of roots rooted from the porcupine culture. 20 is a graph showing the relationship between the photon yield (2) of the photosystem II of black pine and the light intensity in Example 5. FIG. 21 is a graph showing the relationship between the photon yield (2) of the photosystem II of black pine and the light intensity in Example 5. FIG. FIG. 22 is a graph showing the relationship between the light intensity and the rooting rate of pine cuttings in Example 5. FIG. 23 is a graph showing the relationship between the light intensity and the number of roots rooted from the pine cuttings in Example 5. FIG. 24 is a graph showing the relationship between the light intensity in Example 5 and the length of roots rooted from the pine cuttings.

  The plant which this invention makes object is not specifically limited. Examples of the plant include woody plants and herbaceous plants, but woody plants and plants having the ability to produce secondary metabolites are preferred.

  Examples of woody plants include Eucalyptus plants, Pinus plants (such as Pinus thunbergii), Prunus plants (Prunus spp.), And Populus plants (Populus) ( Porcupine (Populus tremula var. Sieboldii), ume (Prunus mume), Prunus tomentosa, etc., Avocado plant, Mangiferan plant (manfia), Mangifera plant, etc. Acacia plants, genus Myrica plants, Quercus plants (Quercus acutisi, etc.) ma)), grape (Vitis) plant, apple (Malus) plant, rose (Rosa) plant, camellia (Camellia) plant, Jacaranda (Jacaranda mimosifolia, etc.), crocodile ( Persea plants (such as Avocado (Persea americana)), Pirus plants (such as Pyrus serotina Rehder and Pyrus pyrifolia), Sandalum plants (such as sandalum) It is done. Among these, a cherry genus plant, a eucalyptus plant, a porcupine genus plant, and a pine genus plant are preferable.

  The secondary metabolite (secondary metabolite) means a substance synthesized by metabolizing the primary metabolite. While primary metabolites are directly involved in plant cell growth, development, reproduction, and other life, secondary metabolites are not directly involved in life. It has functions such as protecting itself from external enemies (pathogenic bacteria, etc.). Examples of secondary metabolites include alkaloids (such as ephedrine), terpenoids, flavonoids, terpene glycosides (such as glycyrrhizin), glycosides, phenols, or derivatives thereof. Secondary metabolites are known to contain components useful for medicines, health aids, anesthetics, dyes and the like, and among these, components useful for medicines, health aids and the like are preferable.

  Medicinal plants are preferred as the plants that accumulate secondary metabolites. The medicinal plant means a plant in which at least a part of the plant is used for medicinal purposes. Medicines include herbal medicines (unrefined medicines, medicinal herbs), traditional Chinese medicines, folk medicines, etc., and include foods that are not classified as pharmaceuticals by the Pharmaceutical Affairs Law. Examples of medicinal plants used for medicinal purposes include whole plants, foliage, flowers, persimmons, seeds, fruits, pericarps, roots, rhizomes, rhizomes, xylem, bark, and plant parts containing two or more of these. Illustrated.

  Medicinal plants include citrus, apricot, irresen, nintendo, fennel, engosaku, ogi, ougon, oak, auren, onji, gayyo, kashi, kankon, casseki, carocon, caroten, licorice, kyouka, kikuka, pheasant , Kyonin, Kujin, Keigai, Keihi, Kouka, Koujin, Kouushi, Koubay, Kokuboku, Goshitsu, Goshuyu, Goboushi, Sesame, Garbage, Psycho, Saishin, Hawthorn, Sanshishi, Sanshuyu, Salamander, Sansonin, Sanyaku, Ganko, Zikoppi, Shikon, Shitsuri, Cinnamon, Peonies, Shazenshi, Zukujiou, Shukusha, Shokyo, Shobakaku, Shouma, Shinyi, Gypsum, Senkyu, Zenko, Senkotsu, Centai Senna, Sojutsu, Sakuhakuhi, Soboku, Soyo, Daio, Taiso, Takusha, Chikujo, Chikusetinjinjin, Chimo, Chaoyou, Clove, Butterflyfish, Chorei, Chinpi, Tennansho, Tenma, Tenmondo, Pepper, Toki, Tonin, Spruce , Tokon, Tochu, Dokatsu, Carrot, Nindo, Baimo, Bakuga, Bakumondo, Hakka, Hakubofuu, Hange, Byakugo, Byakushi, Byakujutsu, Biwayou, Binrouji, Bukkyou, Bushi, Fungatsuame, Bowie, Bofufu, Ukubo , Machinin, mokutsu, mokko, yokoinin, ryuganiku, ryukotsu, ryutan, ryokyou, forsythia, rennik, kyoko katsu, preferably kankyo, licorice Keihi, Goboushi, Sanshi, Chimpi, Biwayo, Carrot, Tonin, Chorei, Soyo, Daio, Taiso, Senna, Peonies, Salamander, Sunshu, Kojijin, Buttonpi, Onji, Ogi Ryutan. Even more preferred is the genus Ephedra. Examples of the genus Maou include E. distachya, E. sinica, and E. equistina Bunge.

  In the present invention, at least a part of the plant is irradiated with light, and the photon yield (1) of the photosystem II on the measurement surface with a diameter of about 2 cm and / or the photosystem II on the measurement surface with a diameter of about 1 mm. The photon yield (2) is measured.

  The types of plants are as described above. The age of the plant is not particularly limited. At least a part of the plant preferably contains leaves, and is preferably leaves. The leaf may be a leaf collected from a plant or a part not collected from a plant. The number of leaves may be one or two or more. The leaves of the plant can be selected randomly from the whole plant body, but are preferably leaves near the top bud and / or leaves taken from external branches. The leaves may or may not be expanded, but are preferably expanded.

The light intensity applied to at least a part of the plant is preferably ²⁰ μmol / m ² / s or more, and preferably 40 μmol / m ² / s or more. The upper limit is preferably not more than 400μmol / m ² / s, preferably not more than 300μmol / m ² / s.

  The light to be irradiated is preferably two or more types of light having different light intensities, and more preferably three or more types of light.

  The light to be irradiated may be red light, blue light, white light, or a combination of two or more selected from these, but is preferably a combination of red light and blue light. The ratio of blue to red is preferably 1: 9 to 5: 5, and more preferably 1: 9 to 3: 7.

Irradiated Examples of a combination of light, the following can be cited; 40,80,160,240 and combinations 280μmol / m ² / s; the combination of 40,80,160 and 240μmol / m ² / s; and 40, A combination of 80 and 160 μmol / m ² / s.

The photon yield (1) is the photon yield of photosystem II when irradiated with saturated light having a light intensity of 7,000 μmol / m ² / s or more, and the photon yield (2) is a light intensity of 15,000 μmol. It is the photon yield of photosystem II when irradiated with saturated light of / m ² / s. The saturated light is an amount of light in which photosynthesis is saturated (quinone A is completely reduced), and may be flash light (flash light) or intermittent light (pulse).

The area of the measurement surface of the photon yield (1) is usually about 314 mm ² . The area of the measurement surface of the photon yield (2) is usually about 0.785 mm ² . The diameter of the measurement surface of the photon yield (1) is usually about 2 cm. The diameter of the measurement surface of the photon yield (2) is usually about 1 mm.

  The shape of each measurement surface of the photon yields (1) and (2) is not particularly limited, and may be a substantially circular shape, a substantially elliptical shape, or a polygonal shape such as a quadrangle. When irradiating light to a leaf, the position of the measurement surface in the leaf is not particularly limited as long as it is a part or all of the leaf. If the measurement surface cannot be ensured because the shape of each leaf is elongated or small, a plurality of leaves may be used as the measurement surface so as to reach the area of the measurement surface by bundling the leaves.

  Both the photon yields (1) and (2) can be measured by a device such as a chlorophyll fluorescence measuring device, an imaging chlorophyll fluorescence measuring device, or a pulse modulation chlorophyll fluorescence measuring device. The photon yield (1) may be measured with a measuring device such as LI-6400 (Li-Cor). The photon yield (2) may be measured by a measuring device such as Mini-PAM (Walz). Examples of the imaging chlorophyll fluorescence measuring apparatus include cfImager (Technology), Fluorcam (PSI), and ImagingPAM (Walz). OS5p + (Opti-Sciences) is illustrated as a pulse modulation chlorophyll fluorescence measuring apparatus.

  In the present invention, both the photon yields (1) and (2) may be measured, or only one of them may be measured. In addition, in both of the photon yields (1) and (2), the measurement may be performed twice or more, and the average value may be used as each measurement value. When measuring twice or more, the measurement surface of each time may be the same, and may differ.

  The carbon dioxide concentration at the time of measuring the photon yield varies depending on the type of plant and the like, but is generally preferably 200 ppm or more, and more preferably 390 ppm or more. The upper limit is preferably 3500 ppm or less, and more preferably 5000 ppm or less. Control of the carbon dioxide concentration may be performed for each culture container by using a sealed container, but may be performed by controlling the carbon dioxide concentration of the environment itself in which the container is placed.

  When measuring in a container, the shape of a container is not specifically limited, What opened the opening part as it is, The thing which covered the opening part with the membrane | film | coat of a carbon dioxide permeability, a sealed type etc. are illustrated.

  The temperature and humidity conditions for the photon yield measurement are not particularly limited, but the temperature is usually 20 to 30 ° C. and the humidity is 30 to 100%.

  In the present invention, the measured value of the photon yield (1) is 0.60 to 0.80 and / or the measured value of the photon yield (2) is 0.20 to 0.42. Specify strength. Depending on the measurement results, the light intensity at which the measured value of the photon yield (1) is 0.60 to 0.80 and the light intensity at which the measured value of the photon yield (2) is 0.20 to 0.42 may be used. In this case, the photon yield (1) and / or (2) is measured again at a light intensity different from the light intensity set at the time of the first measurement. What is necessary is just to measure the light intensity which satisfies the said numerical value.

  In the present invention, a plant cutting or culture is then rooted at the specified light intensity.

  The light applied to the cutting head may be red light, blue light, white light, and a combination of two or more selected from these, but is preferably white light.

  The repetition period of the light period and dark period of irradiation is not particularly limited, but it is preferably 14 to 18 hours of light period per 24 hours / 6 to 10 hours of dark period.

  The cuttings may be part or all of the plant. The cuttings may be at least part of the plant, branches such as green branches (current year branches), mature branches (branches extending before the previous year); buds such as top buds and buds; leaves, cotyledons; hypocotyls Etc. are exemplified. The cuttings in the case of woody plants are usually green branches or mature branches, and the cuttings in the case of herbaceous plants are usually leaves or buds, but the cuttings preferably include at least leaves. The culture may be a part or all of the plant, but preferably contains at least leaves.

  Shoots may be used as cuttings and cultures. Shoots refer to all tissues that have rooting ability. Examples of the tissue include branches, stems, apical buds, buds, adventitious buds, leaves, cotyledons, hypocotyls, adventitious embryos, shoot primordia, and the like. The origin of the shoot is not particularly limited, and may be a tissue obtained from an individual plant growing in a greenhouse or outdoors, or may be a cultured tissue obtained by a tissue culture method, or a part of a natural plant body It may be an organization. The shoot can be efficiently obtained from the main plant or multi-bud of the cutting ear. Among them, cuttings (cutting ears obtained from the mother plant), polyblasts obtained by aseptically culturing organs collected from the mother plant, or foliage obtained by aseptically growing the organs Preferably there is.

  A multi-bud can be derived by cutting out tissues such as apical buds and axillary buds from a plant to which a clone seedling is to be produced by applying the present invention, and culturing the tissue. In order to form and cultivate an organ collected from a mother plant aseptically, the polyblast can be formed according to the method and conditions described in JP-A-8-228621. The method and conditions are as follows. First, tissues such as apical buds and axillary buds are collected from a plant as a material, and about the collected tissues, an aqueous sodium hypochlorite solution having an effective chlorine content of about 0.5% to about 4% or an effective chlorine content of about 5% to Surface sterilization is performed by immersing in an aqueous solution of about 15% hydrogen peroxide for about 10 minutes to about 20 minutes. Next, this is washed with sterilized water, inserted into a solid medium, the buds are opened, and the elongated foliage is subcultured in a medium having the same composition to form a multi-bud. When using Eucalyptus or Acacia tissues (for example, buds), the solid medium is 1 to 5% by weight of sucrose and benzyladenine (hereinafter abbreviated as BA) as a plant hormone is about 0.02 mg / l or more. Murashige Sukug (hereinafter abbreviated as MS) medium containing 1 mg / l or less, gellan gum of about 0.2 wt% to about 0.3 wt% or agar of about 0.5 wt% to about 1 wt%, or MS It is preferable to use a modified MS medium in which the ammonium nitrate component and potassium nitrate component of the medium are halved. The shoots are actively extended from the multi-buds thus formed. The multiblasts themselves can be maintained and proliferated by appropriately dividing them and culturing them in a medium having the same composition as the medium used for the formation of the multibuds.

  The humidity of the cultivation environment in the step of rooting from the cuttings is not particularly limited as long as it is appropriately adjusted depending on the target plant, but is preferably 60% Rh or more, more preferably 80% Rh or more, More preferably, it is 90% Rh or more. Thereby, rooting from a plant can be promoted. There is no restriction | limiting in particular about the upper limit of humidity, What is necessary is just 100% Rh or less. In the case of plants where mold tends to grow, it is more preferably 80% Rh or less, and even more preferably 70% Rh or more.

  The carbon dioxide gas concentration in the cultivation environment in the step of rooting from the cuttings is usually 300 ppm or more, preferably 350 ppm or more, more preferably 400 ppm or more. The upper limit is usually 2000 ppm or less, preferably 1500 ppm or less, 1250 ppm or less, more preferably 1000 ppm. Control of the supply amount of carbon dioxide gas can be performed using equipment such as an artificial weather device, a culture vessel having a carbon dioxide permeable membrane in the opening, and the like.

  The temperature of the cultivation environment in the step of rooting from the cuttings is preferably about 23 ° C. or higher and about 28 ° C. or lower.

  In the process of rooting from the cuttings, the distribution of the light period and dark period is usually 1: 1 to 3: 1 and preferably 3: 2 to 5: 2.

  In the step of rooting from the cutting head, it is preferable to perform light shielding. The light shielding rate is preferably 30% or more and 70% or less, and more preferably 40% or more and 60% or less.

  The period of rooting from the cuttings varies depending on the cultivation conditions such as the type of plant, but is usually 2 weeks to 3 months, and preferably 4 weeks to 2 months. Continue until rooting is observed from the cuttings.

  In the step of rooting from cuttings, a rooting medium is usually used. In the present invention, the rooting medium means a medium used for rooting from cuttings.

The rooting medium preferably contains silver ions and / or antioxidants, and more preferably contains both silver ions and antioxidants. Silver ions may be added to the medium as a silver compound (silver ion source) such as silver thiosulfate (STS, AgS ₄ O ₆ ) or silver nitrate. Among them, STS is preferable as a silver ion source used in the present invention, since healthy roots and / or elongation is promoted when added to a medium and cultured for shoots. This is presumably because silver ions derived from STS take the form of silver thiosulfate ions in the medium and are negatively charged. The concentration of silver ions in the rooting medium depends on the type of silver ion source and other culture conditions, but the concentration of the silver ion source is preferably about 0.5 μM or more and about 6 μM or less, and about 2 μM or more and about 6 μM or less. Is more preferable.

  On the other hand, as the antioxidant, for example, known antioxidants such as oxidized glutathione (GSSG), ascorbic acid, sulfite and the like can be used, and oxidized glutathione is preferable. The concentration of oxidized glutathione in the rooting medium is preferably 1 mg / l to 100 mg / l, more preferably 5 mg / l to about 75 mg / l.

  The rooting medium may further contain components such as an inorganic component, a carbon source, vitamins, amino acids, and plant hormones.

  Inorganic components include elements such as nitrogen, phosphorus, potassium, sulfur, calcium, magnesium, iron, manganese, zinc, boron, molybdenum, chlorine, iodine, cobalt, and one or more elements selected from these elements Inorganic salts are exemplified. Examples of inorganic salts include potassium nitrate, ammonium nitrate, ammonium chloride, sodium nitrate, potassium monohydrogen phosphate, sodium dihydrogen phosphate, potassium chloride, magnesium sulfate, ferrous sulfate, ferric sulfate, manganese sulfate, zinc sulfate, These hydrates include copper sulfate, sodium sulfate, calcium chloride, magnesium chloride, boric acid, molybdenum trioxide, sodium molybdate, potassium iodide, cobalt chloride and the like. 1 type may be sufficient as an inorganic component, and the combination of 2 or more types may be sufficient as it.

  The rooting medium preferably contains nitrogen, phosphorus and potassium as essential elements. Therefore, among the specific examples of the above-described inorganic components, nitrogen, phosphorus, potassium, an inorganic salt containing nitrogen, an inorganic salt containing phosphorus, and an inorganic salt containing potassium are preferable, and include nitrogen, phosphorus, potassium, and nitrogen. Inorganic salts are more preferred. The concentration of the inorganic component in the rooting medium is preferably 0.1 μM to 100 mM, and more preferably 1 μM to 100 mM, when there is only one inorganic component. When the inorganic component is a combination of two or more, it is preferably 0.1 μM to 100 mM, and more preferably 1 μM to 100 mM.

  Examples of the carbon source include carbohydrates such as sucrose and derivatives thereof; organic acids such as fatty acids; primary alcohols such as ethanol. 1 type may be sufficient as a carbon source, and 2 or more types may be sufficient as it. The concentration of the carbon source in the rooting medium is preferably 1 g / l to 100 g / l, and more preferably 10 g / l to 100 g / l. However, when culture is performed while supplying carbon dioxide gas, the culture medium does not need to contain a carbon source, and preferably does not contain it. Organic compounds that can serve as a carbon source such as sucrose can also serve as a carbon source for microorganisms. Therefore, when using a medium supplemented with these, it is necessary to culture in a sterile environment, but use a medium that does not contain a carbon source. This makes it possible to culture in a non-sterile environment.

  Examples of vitamins include biotin, thiamine (vitamin B1), pyridoxine (vitamin B4), pyridoxal, pyridoxamine, calcium pantothenate, inositol, nicotinic acid, nicotinamide and riboflavin (vitamin B2). 1 type of vitamin may be sufficient and the combination of 2 or more types may be sufficient. The concentration of vitamins in the rooting medium is preferably 0.01 mg / l to 200 mg / l, more preferably 0.02 mg / l to 100 mg / l when the number of vitamins is one. When the vitamin is a combination of two or more, it is preferably 0.01 mg / l to 150 mg / l, more preferably 0.02 mg / l to 100 mg / l.

  Examples of amino acids include glycine, alanine, glutamic acid, cysteine, phenylalanine and lysine. 1 type may be sufficient as an amino acid and 2 or more types may be sufficient as it. The concentration of the amino acid in the rooting medium is preferably about 0.1 mg / l or more and about 1000 mg / l or less when one amino acid is used, and is 0. It is preferable that it is 2 mg / l-1000 mg / l.

  Examples of plant hormones include auxin and cytokinin. Examples of auxins include naphthalene acetic acid (NAA), indole acetic acid (IAA), p-chlorophenoxyacetic acid, 2,4-dichlorophenoxyacetic acid (2,4D), indolebutyric acid (IBA), and derivatives thereof. . One auxin may be used or a combination of two or more auxins may be used. Examples of cytokinins include benzyladenine (BA), kinetin, zeatin, 6-benzylaminopurine (BAP), and derivatives thereof. Cytokinin may be one kind or a combination of two or more kinds. The plant hormone may be auxin alone, cytokinin alone, or a combination of auxin and cytokinin. In general, auxin acts on rooting, and cytokinin acts on growth. Therefore, after culturing the ear by adding only cytokinin, it can be rooted by adding auxin. The concentration of the plant hormone in the rooting medium is preferably 0.01 mg / l to 10 mg / l, more preferably 0.02 mg / l to 10 mg / l when one kind of plant hormone is used. preferable. When there are two or more kinds of plant hormones, it is preferably 0.01 mg / l to 10 mg / l, and more preferably 0.02 mg / l to 10 mg / l.

  As the rooting medium, a medium in which silver ions and / or an antioxidant, a carbon source, or plant hormones are appropriately added to a medium known as a plant tissue culture medium as necessary may be used. Examples of media known as plant tissue culture media include MS media, Rinsmeier Skoog media, white media, Gamborg B5 media, niche niche media, and the like. Of these, MS medium and Gamborg B5 medium are preferred. These media can be used by appropriately diluting them as necessary.

  The rooting medium may be either a liquid medium or a solid medium, but the liquid medium is preferable in terms of work efficiency and less damage to the roots during transplantation. In the case of a liquid medium, the medium composition may be mixed and prepared and used as it is. In the case of a solid medium, the medium composition can be mixed and prepared in the same manner as the liquid medium, or can be used after being adjusted and solidified with a solidifying agent such as agar or gellan gum. The amount of the solidifying agent added to the medium varies depending on the kind of the solidifying agent and the composition of the medium. When the solidifying agent is agar, it is preferably 0.5% by weight or more and 1% by weight or less. When the solidifying agent is gellan gum, the content is preferably 0.2% by weight or more and 0.3% by weight or less.

  What is necessary is just to select suitably the insertion method of the cutting head to the culture medium for rooting according to the kind of culture medium, culture conditions, etc. When the rooting medium is a solid medium, the rooting medium may be directly inserted into the rooting medium and cultured. On the other hand, when the rooting medium is a liquid medium, for example, the support described later may be wetted with the rooting medium, and then the base of the cutting ear may be inserted and cultured. In order to improve the rooting rate, it is also preferable to apply a physical stimulus such as damaging the base of the cutting head when inserted into the rooting medium. The base of the cutting head means a region (one side opposite to the end where the leaf is formed) which is one end of the cutting head and a root is formed. The base in the case of using a multi-bud as an insertion ear is a region having a cut surface when dividing the multi-bud. The size (size, shape, etc.) of the damage to the base of the cutting head is not particularly limited. For example, in the case where a multi-bud is used as the cutting head, it is preferable to scratch the base of the cutting head (the above-mentioned cut surface) so as to form a cross when viewed from the front. When scratching, instruments such as scissors and knives can be used.

  In the present invention, the support is a support for supporting the cutting head. When using a rooting medium (especially a solid medium), a support may be unnecessary. In other cases, a support is usually used.

  The support is preferably a support that can be held in a state where the cutting head is pointed during the cultivation period. When a liquid rooting medium is used for cultivation, it is usually used by infiltrating a support. Accordingly, the support is preferably a support that can be infiltrated with a liquid, and among them, a support that can be substantially uniformly wetted by a liquid medium is preferable. A conventional support may be used as the support, and is not particularly limited. Examples of the support include natural soils such as sand and red bean clay; artificial soils such as rice husk charcoal, coconut fiber, vermiculite, perlite, peat moss, and glass beads; and porous molded articles such as foamed phenol resin and rock wool. be able to. The root bed can be prepared by placing the support in a culture vessel. When the rooting medium is a solid medium, the rooting bed can be prepared by placing the solid medium directly into the culture vessel.

  In the present invention, it is preferable to use a culture vessel for storing a rooting medium or a support. As the culture vessel, a conventional culture vessel can be used, and is not particularly limited. For example, a seedling pot, a plug tray, etc. are illustrated. The culture vessel may be a closed type or an open type, but a closed type culture vessel is preferable because it facilitates maintaining the humidity of the environment surrounding the cuttings and cuttings and seedlings formed therefrom.

  When a branch is used as the cutting head, it is preferable to use a closed culture vessel as the culture vessel. This makes it easy to place the cutting head under high humidity, so that the transpiration action of the leaves on the branches is suppressed, and the conventional partial excision processing of the leaves can be omitted.

  The culture container is more preferably a container capable of supplying carbon dioxide gas into the container. As such a culture container, a container having an opening covered with a carbon dioxide permeable membrane is exemplified. By using a container having an opening covered with a carbon dioxide permeable membrane, the humidity of the culture environment can be easily adjusted. The shape of the opening is not particularly limited. The material for the carbon dioxide permeable membrane is not particularly limited, and examples thereof include polytetrafluoroethylene. The pore diameter of the membrane is not particularly limited, and examples thereof include membranes having a pore diameter of about 0.1 μm or more and about 1 μm or less.

  In the present invention, the temperature of the support and / or rooting medium is usually 20 ° C to 30 ° C, preferably 22 ° C to 26 ° C.

  In the present invention, plants may be cultivated, for example, by raising cuttings after rooting and cutting seedlings obtained from the culture. For example, the obtained cuttings can be transplanted and grown in a seedling container or a nursery. When the cutting or culture is a shoot derived from a cultured tissue such as adventitious buds, shoot primordia, etc., it usually undergoes an acclimatization step before transplantation to a seedling container or the like. Conditions suitable for cutting seedlings may be set as appropriate for conditions such as temperature, light intensity during cultivation, and the type and amount of soil to be stored in the seedling container. A plant and its secondary metabolite can be obtained through the process of growing a cutting seedling.

Example 1
1) Target plant Yoshino cherry was used.

2) Measurement of quantum yield of photosystem II The CO ₂ concentration in the measurement chamber was adjusted to 400 or 1000 ppm, the temperature was adjusted to 24 to 26 ° C., and the humidity was adjusted to 50 to 70%. A branch with leaves of Yoshino cherry was introduced into the chamber, and light was randomly applied to the selected leaves to measure the quantum yield (chlorophyll fluorescence) of Photosystem II. The light intensity was adjusted to 40, 80, 160, 240, 320, 640, and 960 μmol / m ² / s. The chlorophyll fluorometer was LI-6400 (Li-Cor), the measurement area was 314 mm ² (diameter approximately 20 mm), and the light intensity of saturated light was 7,000 μmol / m ² / s (flash light). The light to irradiate was a photosynthetic wavelength with a blue to red ratio of 2: 8. The results are shown in Table 1 and FIGS. In addition, the quantum yield in Table 1 and a figure is an average value of the measured value about five or more leaves or five or more parts.

3) Rooting culture Five roots of Yoshino cherry (collected in June 2014) were inserted into the rooting medium for each light irradiation condition, and rooted. The light irradiation conditions were light intensity of 40, 80, 160, and 240 μmol / m ² / s. The rooting medium was a 1/5 diluted B5 medium (manufactured by Wako Pure Chemical Industries, Ltd.), and the IBA concentration was adjusted to 2 mg / L and 5 μM silver thiosulfate was added. The culture conditions were a CO ₂ concentration of 1000 ppm, a temperature of 25 ° C., a humidity of 60%, and a culture period of 18 days. The light to irradiate was made into the wavelength of blue and red ratio 2: 8.

4) Confirmation of rooting situation After completion of the rooting culture period, the rooting rate of the cuttings, the number of roots, and the length of the roots were measured, and the average value for each light irradiation condition was measured. The results are shown in Table 1 and FIGS.

Example 2
1) Target plant Round leaf eucalyptus was used.

2) Measurement of quantum yield of photosystem II The CO ₂ concentration in the measurement chamber was adjusted to 1000 ppm, the temperature was adjusted to 25 ° C, and the humidity was adjusted to 60 ° C. After placing the leaf eucalyptus leaves in the respective light environment for 5 minutes or more in advance, the quantum yield (chlorophyll fluorescence) of photosystem II was measured. The measurement was performed by placing the sample on the slide glass and grounding the optical fiber to the slide glass so that the longitudinal direction of the optical fiber of the measuring apparatus was 90 ° with respect to the sample. The measuring device was Mini-PAM (manufactured by WALZ), the measurement area was 0.785 mm ² (diameter: about 1 mm), and the light intensity of saturated light was 15,000 μmol / m ² / s (flash light). The light environment was light irradiation with light intensities of 40, 80, 160, 240, and 280 μmol / m ² / s. The results are shown in Table 3 and Figs. In addition, the quantum yield in Table 2 and a figure is an average value of the measured value about five or more leaves or five or more parts.

3) Rooting culture The sample was a round-leaf eucalyptus culture, the number of samples for each light irradiation condition was 25, the culture period was 3 weeks, and the irradiated light was white (blue and red) Example 1 except that the light was from a cold cathode tube having a wavelength of 5: 3) and the light irradiation conditions were light intensity of 40, 80, 160, 240 and 280 μmol / m ² / s. Same as item 3. The culture was prepared under the following conditions: MS medium, BAP 0.2 mg / L, MS vitamins, 2.5 g / L, sucrose 20 g / L, gellan gum 2.5 g / L to pH 5.5. The ears were cut out from the tissue culture that had been extended with the conditioned medium. Thereafter, a rooting medium obtained by adding 5 mg / L of IBA to a 5-fold diluted B5 medium was immersed in an oasis as a rooting support, and the cuttings were inserted into the oasis and cultured in a container for 4 weeks.

4) Confirmation of rooting situation It carried out like the item 4 of Example 1. The results are shown in Table 4 and FIGS.

Example 3
1) Target plant Maoh (Ephedra sinica) was used.

2) Measurement of quantum yield of photosystem II It was carried out in the same manner as in item 2 of Example 2 except that the light irradiation conditions were light intensity of 40, 80, 160 and 240 μmol / m ² / s. The results are shown in Table 4 and FIGS. In addition, the quantum yield in a table | surface and a figure is an average value of the measured value about five or more leaves or five or more parts.

3) Rooting culture The sample was a mao culture, the number of samples per light irradiation condition was 12, the culture period was 4 weeks, and the light irradiation conditions were light intensity 40, 80, 160. And 240 μmol / m ² / s, and the same procedure as in item 3 of Example 1 except that the IBA concentration was 5 mg / L. The culture was prepared under the following conditions: MS medium, BAP 2 mg / L, MS vitamin, sucrose 20 g / L, gellan gum 2.5 g / L, and tissue elongated with medium adjusted to pH 5.5 The cuttings were cut out from the culture. A rooting medium obtained by adding 5 mg / L of IBA to a 5-fold diluted B5 medium was immersed in an oasis as a rooting support. The cuttings were inserted into an oasis and cultured in a container for 6 weeks.

4) Confirmation of rooting situation It carried out like the item 4 of Example 1. The results are shown in FIGS.

Example 4
1) Target plant Porcupine (poplar) was used as a sample.

2) Measurement of quantum yield of photosystem II Example 3 except that the light irradiation conditions were light intensity of 40, 80, 160 and 240 μmol / m ² / s, and the CO ₂ concentration was 400 or 1000 ppm. This was performed in the same manner as item 2. The results are shown in Table 5 and FIG. In addition, the quantum yield in Table 5 and a figure is an average value of the measured value about five or more leaves or five or more parts.

3) Rooting culture The sample was a porcupine culture, the number of specimens per light irradiation condition was 10, the culture period was 10 days, and the CO ₂ concentration was 400 or 1000 ppm. Except for this, the same procedure as in item 3 of Example 1 was performed. The culture was prepared under the following conditions: MS medium, BAP 2 mg / L, MS vitamin, sucrose 20 g / L, gellan gum 2.5 g / L, and tissue elongated with medium adjusted to pH 5.5 The cuttings were cut out from the culture. A rooting medium in which IBA 2 mg / L was added to a 5-fold diluted B5 medium was immersed in an oasis as a rooting support. The cuttings were inserted into an oasis and cultured in a container for 4 weeks.

4) Confirmation of rooting situation It carried out like the item 4 of Example 1. The results are shown in Table 5 and FIGS.

Example 5
1) Target plant Black pine was used.

2-1) Measurement of photosystem II quantum yield with LI-6400 The black pine leaves are long and thin, so the leaves are arranged horizontally and both ends are taped to create a planar bundle, and the bundle is put into the chamber. Photosystem II quantum yield (chlorophyll fluorescence) was measured by illuminating the leaf bundle. The CO ₂ concentration was adjusted to 1000 ppm. Others were the same as item 2 in Example 1. The results are shown in Table 2. The culture was prepared under the following conditions: V-shaped cuttings were collected from seedlings planted in pots. A rooting medium obtained by adding 10 mg / L of IBA to a 5-fold diluted B5 medium was immersed in an oasis as a rooting support. The cuttings were inserted into an oasis and cultured in a container for 8 weeks.

2-2) Measurement of quantum yield of photosystem II by Mini-PAM The same procedure as in item 2 of Example 2 was performed, except that the light irradiation conditions were light intensity of 40, 80 and 160 μmol / m ² / s. . The results are shown in Table 6 and Figs. In addition, the quantum yield in a table | surface and a figure is an average value of each measured value of 3 bundles.

3) Rooting culture Samples were pine cuttings (collected in June 2014), the number of samples per light irradiation condition was 50, the culture period was 8 weeks, light irradiation conditions Was carried out in the same manner as in item 3 of Example 1 except that the light intensity was 40, 80 and 160 μmol / m ² / s and the IBA concentration was 10 mg / L.

4) Confirmation of rooting situation It carried out like the item 4 of Example 1. The results are shown in FIGS.

In Yoshino cherry, the light intensity when the quantum yield of Photosystem II is 0.66 is 160 μmol / m ² / s, and when the cuttings of Yoshino cherry are cultured at a light intensity of 160 μmol / m ² / s, the rooting rate and root The number and the length of the roots were both favorable (Example 1). In round leaf eucalyptus, when the quantum efficiency of photosystem II is 0.18, the light intensity is 240 μmol / m ² / s. Both the root length and the root length were favorable (Example 2). In Maou, when the quantum yield of Photosystem II is 0.24, the light intensity is 160 μmol / m ² / s, and when the Mao culture is cultured at a light intensity of 160 μmol / m ² / s, the rooting rate and root The number and the length of the roots were both good (Example 3). In aspen, the light intensity when the quantum efficiency of photosystem II 0.34 is 80μmol / m ² / s, when cultured aspen cultures intensity 80μmol / m ² / s rooting ratio, the number of roots And the length of the roots was good (Example 4). In black pine, when the quantum efficiency of photosystem II is 0.70 (LI-6400: Table 2) and 0.24 (Mini-PAM: Table 6), the light intensity is 80 μmol / m ² / s. When the cuttings of round leaf eucalyptus were cultured at 80 μmol / m ² / s, the rooting rate, the number of roots and the length of the roots were all good (Example 5). In Examples 1 and 4, it was found that the same light intensity was preferable regardless of the CO ₂ concentration of 400 and 1000 ppm.

  These results show that according to the method of the present invention, the optimal rooting culture conditions according to the conditions such as the type of plant can be easily identified, and the rooting rate of seedlings, the number of roots and the length of roots are determined. It shows that it can be improved.

Claims (5)

Photosystem II photon yield (1) and / or light intensity 15, when irradiating at least part of the plant with light and irradiating saturated light with a light intensity of 7,000 μmol / m ² / s or higher, Measuring photon yield (2) of photosystem II when irradiated with saturated light of 000 μmol / m ² / s,
Specifying the light intensity where the measured value of the photon yield (1) is 0.60 to 0.80 and / or the measured value of the photon yield (2) is 0.20 to 0.42. including,
A method for evaluating light intensity suitable for rooting of a plant cutting or a culture.   The method for evaluating light intensity according to claim 1, wherein the plant is a cherry genus plant, a eucalyptus genus plant, a genus genus plant, a porcupine genus plant or a pine genus plant.   A method for rooting a plant cutting or culture, comprising irradiating light of the light intensity specified by the method according to claim 1 or 2 to root the plant cutting or culture.   A method for producing a plant cutting seedling for planting, wherein the plant cuttings or culture is rooted by irradiating light having the light intensity specified by the method according to claim 1 or 2.   A method for cultivating a plant, comprising irradiating light having a light intensity specified by the method according to claim 1 or 2 and rooting a cutting or a culture of the plant.