JP5529224B2 - Cell differentiation promoting agent and use thereof - Google Patents

Description

  The present invention relates to a cell differentiation promoter and use thereof.

  The cutting method that inserts the cuttings into the floor or medium and roots, and the tissue culture method that cultivates plant tissues and collects adventitious buds and roots them for agricultural production, planting, breeding, and other fields. Is used as a means for mass production of homogeneous plants (clonal seedlings) having traits suitable for the purpose. In these methods, the rooting ability of plant tissues greatly affects the productivity of cloned seedlings, so it is important to improve rooting ability.

  Japanese Patent Application Laid-Open No. 2001-231355 (Patent Document 1) discloses that a plant selected from a Eucalyptus plant and an Acacia plant is treated with pacloputrazole before being collected as an insertion head, and a plant is developed. It is described that root ability is promoted.

  On the other hand, in Japanese Patent Application Laid-Open No. 2002-47108 (Patent Document 2), a triazole compound having a specific structure has an action of inhibiting the metabolism of brassinosteroid in plants, and the growth (growth) and development of plants It is described as being useful for regulation. Japanese Patent Application Laid-Open No. 2003-113008 (Patent Document 3) discloses that when the triazole compound described in Patent Document 2 is allowed to act on a plant together with a plant growth hormone such as benzyladenine, plant growth is promoted. Is described.

JP 2001-231355 A JP 2002-47108 A JP 2003-113008 A

  However, in the method described in Patent Document 1, it has been difficult to obtain cuttings after several months have passed since the harvesting mother tree was previously treated with pacloputrazole. For this reason, there has been a demand for an immediate effect in improving rooting ability.

  On the other hand, the methods of Patent Documents 2 and 3 are methods for controlling brassinosteroids related to plant growth. Therefore, it is different from a technique for promoting rooting of cuttings, such as cutting method, that is, a technique for promoting only differentiation of root tissue. In general, the conditions for promoting rooting of cuttings are different from the conditions for promoting plant growth. In many cases, the rooting of cuttings is promoted by conditions that stop plant growth.

  In addition, the method described in Patent Document 1 has insufficient rooting ability for plants. In particular, when this method was originally applied to plants with low rooting ability (for example, Eucalyptus plants), improvement of rooting ability could not be expected.

  An object of this invention is to provide a compound useful as an active ingredient of a cell differentiation promoter. Examples of the compound include a compound that can be an active ingredient of an adventitious root rooting promoter that promotes rooting from plants and improves the rooting rate. Further, the present invention belongs to a plant species having low rooting ability, in order to improve the productivity of cloned seedlings by a method such as cutting method or tissue culture method using a cell differentiation promoting agent containing the compound. An object of the present invention is to provide a rooting method and a rooting medium for improving the productivity of cloned seedlings. Furthermore, this invention aims at providing a novel compound.

The present invention provides the following [1] to [21].
[1] A compound represented by any one of General Formula (1-1), General Formula (1-2), General Formula (1-3), General Formula (2-1), and General Formula (2-2) Or the cell differentiation promoter containing the salt.
(In the general formula (1-1), R ¹¹¹ represents a hydrogen atom, a hydroxyl group or an alkyl group, R ¹¹² represents an alkyl group or an aromatic hydrocarbon group which may have a substituent, and R ¹¹³ represents a substituent. (Aromatic hydrocarbon group that may have a wavy line in a cis configuration or a trans configuration.)
(In the general formula (1-2), R ¹²¹ is a hydrogen atom, an alkyl group or an alkoxyalkyl group, R ¹²² is an aromatic hydrocarbon group which may have a substituent, and R ¹²³ and R ¹²⁴ are Each independently a hydrogen atom or an alkyl group.)
(In General Formula (1-3), R ¹³¹ is a hydrogen atom, an alkyl group or an alkenyl group, R ¹³² is an aromatic hydrocarbon group which may have an alkyl group or a substituent, and R ¹³³ is a substituent. An aromatic hydrocarbon group that may have
(In the general formula (2-1), R ²¹¹ is an aromatic hydrocarbon group which may have a substituent or a heterocyclic group which may have a substituent, m is 1 or 2, and n is 0 or 1 and A is a nitrogen atom or —CH—.)
(In the general formula (2-2), R ²²¹ is a hydrogen atom, an alkyl group or a halogenated alkyl group, R ²²² is a hydrogen atom, an alkyl group or a halogen atom, and p is an integer of 1 to 5. )
[2] The R ¹¹¹ is a hydroxyl group, the R ¹¹² is a 4-chlorophenyl group or a t-butyl group, and the R ¹¹³ is a 4-methylphenyl group or a 4-dimethylaminophenyl group. The cell differentiation promoter described in 1.
[3] R ¹²¹ is an ethyl group, methyl group, n-propyl group or methoxymethyl group, and R ¹²² is a 4-chlorophenyl group, 4-methylphenyl group, n-butoxyphenyl group or 2,4-dichlorophenyl. The cell differentiation promoter according to [1] above, wherein R ¹²³ and R ¹²⁴ are both hydrogen atoms.
[4] In the above [1], R ¹³¹ is a hydrogen atom, a methyl group or a 3-propenyl group, R ¹³² is a 4-chlorophenyl group or a phenyl group, and R ¹³³ is a 4-chlorophenyl group. The cell differentiation promoting agent described.
[5] The cell differentiation promoting agent according to [1], wherein R ²¹¹ is a naphthyl group, m is 2, and n is 0.
[6] The cell differentiation promoting agent according to [1], wherein R ²¹¹ is a 4-phenoxyphenyl group, m is 1, n is 1, and A is a nitrogen atom.
[7] The cell differentiation promoter according to [1] above, wherein R ²¹¹ is a 3-indole group, m is 1, n is 0, and A is a nitrogen atom.
[8] The cell differentiation promoting agent according to claim 1, wherein R ²²¹ is a methyl bromide group, R ²²² is a fluorine atom, and p is 2.
[9] The cell differentiation promoting agent according to any one of [1] to [8], wherein the cell is a plant cell.
[10] The cell differentiation promoter according to any one of [1] to [9], which is a plant adventitious root formation promoter.
[11] A culture medium for rooting of plant shoots, comprising the cell differentiation promoting agent according to any one of [1] to [10] above.
[12] A method for producing a cloned seedling, wherein a plant shoot is cultivated in the presence of the cell differentiation promoting agent according to any one of [1] to [10] and rooted from the shoot.
[13] A method for producing a cloned seedling, wherein a plant shoot is cultivated in the rooting medium described in [11] above and rooted from the shoot.
[14] Any of the general formula (1-1), the general formula (1-2), the general formula (1-3), the general formula (2-1), and the general formula (2-2) A method of promoting cell differentiation using a compound represented by the formula or a salt thereof.
[15] The method for promoting cell differentiation according to [14] above, wherein the cell is a plant cell.
[16] The method for promoting cell differentiation according to [14] or [15] above, wherein the cell differentiation is promotion of adventitious root formation in plants.
[17] A novel compound represented by the above general formula (2-1) or the above general formula (2-2) or a salt thereof.
[18] The compound according to [17] above, wherein R ²¹¹ is a naphthyl group, m is 2 and n is 0.
[19] The compound according to [17] above, wherein R ²¹¹ is a 4-phenoxyphenyl group, m is 1, n is 1, and A is a nitrogen atom.
[20] The compound according to [17] above, wherein R ²¹¹ is a 3-indole group, m is 1, n is 0, and A is a nitrogen atom.
[21] The compound according to [17], wherein R ²²¹ is a methyl bromide group, R ²²² is a fluorine atom, and p is 2.

Examples of the present invention include the following [1-1] to [1-8].
[1-1] Plant adventitious root formation accelerator containing the compound represented by any one of the above general formula (1-1), the above general formula (1-2) and the above general formula (1-3) or a salt thereof .
[1-2] The R ¹¹¹ is a hydroxyl group, the R ¹¹² is a 4-chlorophenyl group or a t-butyl group, and the R ¹¹³ is a 4-methylphenyl group or a 4-dimethylaminophenyl group. 1-1] Adventitious root formation promoter.
[1-3] R ¹²¹ is an ethyl group, a methyl group, an n-propyl group, or a methoxymethyl group, and the R ¹²² is a 4-chlorophenyl group, a 4-methylphenyl group, an n-butoxyphenyl group, or 2, The adventitious root formation accelerator according to the above [1-1], which is a 4-dichlorophenyl group, and both R ¹²³ and R ¹²⁴ are hydrogen atoms.
[1-4] The R ¹³¹ is a hydrogen atom, a methyl group or a 3-propenyl group, the R ¹³² is a 4-chlorophenyl group or a phenyl group, and the R ¹³³ is a 4-chlorophenyl group. -1] adventitious root formation promoter.
[1-5] An auxin activity promoter comprising a compound represented by any one of the above general formula (1-1), general formula (1-2) and general formula (1-3) or a salt thereof.
[1-6] Plant shoots containing the adventitious root formation promoter according to any one of [1-1] to [1-4] or the auxin activity promoter according to [1-5] above Rooting medium.
[1-7] Plant shoots in the presence of the adventitious root formation promoter according to any one of [1-1] to [1-4] above or the auxin activity promoter according to [1-5] above. A method for producing a cloned seedling, which is cultivated and rooted from the shoot.
[1-8] A method for producing a cloned seedling, wherein a plant shoot is cultivated in the rooting medium described in [1-6] above and rooted from the shoot.

As another aspect of the present invention, the following [2-1] to [2-13] may be mentioned.
[2-1] A novel compound represented by the above general formula (2-1) or the above general formula (2-2) or a salt thereof.
[2-2] The compound according to [2-1], wherein R ²¹¹ is a naphthyl group, m is 2, n is 0, and A is a nitrogen atom.
[2-3] The compound according to [2-1], wherein R ²¹¹ is a 4-phenoxyphenyl group, m is 1, n is 1, and A is a nitrogen atom.
[2-4] The compound according to [1], wherein R ²¹¹ is a 3-indole group, m is 1, and n is 0.
[2-5] The compound according to [2-1] above, wherein R ²²¹ is a methyl bromide group, R ²²² is a fluorine atom, and p is 2.
[2-6] A cell differentiation promoter containing the compound according to any one of [2-1] to [2-5].
[2-7] The cell differentiation promoter according to [2-6] above, wherein the cells are plant cells.
[2-8] A plant adventitious root formation promoter containing the compound according to any one of [2-1] to [2-5].
[2-9] A plant hormone activity promoter containing the compound according to any one of [2-1] to [2-5] above.
[2-10] The plant hormone activity promoter according to [2-9] above, wherein the plant hormone is auxin.
[2-11] Rooting of plant shoots containing the adventitious root formation promoter according to [2-8] above or the plant hormone activity promoter according to [2-9] or [2-10] above Medium.
[2-12] Plant shoots are cultivated in the presence of the adventitious root formation promoter according to [2-8] above, or the plant hormone activity promoter according to [2-9] or [2-10] above, A method for producing a cloned seedling, which is rooted from the shoot.
[2-13] A method for producing a cloned seedling, wherein a plant shoot is cultivated in the rooting medium described in [2-11] above and rooted from the shoot.

  According to the present invention, cell differentiation can be promoted. Adventitious root formation from plants can be promoted and rooting rate can be improved. The promotion of adventitious root formation is brought about by promotion of the activity of plant hormones such as auxins (hereinafter sometimes simply referred to as “auxin”). Therefore, according to the present invention, the productivity of cloned seedlings can be improved. According to the present invention, the productivity of a cloned seedling of a plant species having low rooting ability can be particularly remarkably improved. Therefore, the present invention contributes to the large-scale and rapid production of cloned seedlings of a wide variety of plant species, and in particular, even a plant species with low rooting ability can produce a large amount of cloned seedlings quickly. And open the way to its industrial use.

FIG. 1 is a graph showing the rooting rate of each compound in Eucalyptus plants in Examples 1 to 12 and Comparative Examples 2 to 5. 2-1 is a figure which shows the mode of the rooting of the eucalyptus plant cultivated without the addition in the comparative example 1. FIG. FIG. 2-2 is a diagram showing the state of rooting of a eucalyptus plant cultivated in the presence of compound MA65 in Example 11. FIG. 3 is a graph showing the rooting rate of MA65 for round-leaf eucalyptus in Example 13. 4-1 is a figure which shows the GUS activity of Arabidopsis thaliana cultivated in the presence of compound MA65 in Example 14. FIG. 4-2 is a figure which shows the GUS activity of Arabidopsis thaliana cultivated in the presence of compound MA65 in Example 14. FIG. 4-3 is a figure which shows the GUS activity of Arabidopsis thaliana cultivated without addition in Comparative Example 7. FIG. 4-4 is a figure which shows the GUS activity of the Arabidopsis thaliana cultivated without the addition in the comparative example 7. FIG. FIG. 5 is a graph showing the rooting rate of each compound in Examples 15 to 19 and Comparative Examples 8 to 12 with respect to a eucalyptus plant. FIG. 6 is a graph showing rooting rates of KSR 221 with respect to round leaf eucalyptus in Example 20 and Comparative Example 13.

  The cell differentiation promoter of the present invention is any one of General Formula (1-1), General Formula (1-2), General Formula (1-3), General Formula (2-1), and General Formula (2-2). Or a salt thereof. In addition, the adventitious root formation accelerator of the present invention is represented by general formula (1-1), general formula (1-2), general formula (1-3), general formula (2-1), and general formula (2-2). Or a salt thereof, or a salt thereof. Substituents that can be contained in the compounds represented by formula (1-1), formula (1-2), formula (1-3), formula (2-1), and formula (2-2) The definition of will be described first.

  In the present invention, examples of the alkyl group include alkyl groups having about 1 to 6 carbon atoms. The alkyl group may be either a straight chain or a branched chain. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an iso-butyl group, and a tert-butyl group. Group, ethyl group, n-propyl group, n-butyl group and tert-butyl group are preferred.

  In the present invention, examples of the alkoxyalkyl group include alkoxyalkyl groups having about 1 to 15 carbon atoms. The alkyl chain portion of the alkoxyalkyl group may be either a straight chain or a branched chain, and is preferably a straight chain. The alkoxy part of the alkoxyalkyl group may be either a straight chain or a branched chain, and is preferably a straight chain. Examples of the alkoxyalkyl group include a methoxymethyl group and a methoxyethyl group, and a methoxymethyl group is preferable.

  In the present invention, examples of the alkenyl group include alkenyl groups having 2 to 6 carbon atoms. The alkenyl group may be either a straight chain or a branched chain, but is preferably a straight chain. As an example of an alkenyl group, a vinyl group, an allyl group, 1-propenyl group, 2-propenyl group, 2-butenyl group etc. are mentioned, 2-propenyl group is preferable.

In the present invention, the alkoxy group is exemplified by an alkoxy group having 1 to 6 carbon atoms. The alkoxy group may be either a straight chain or a branched chain, but is preferably a straight chain. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, an iso-butoxy group, and an n-butoxy group, and the n-butoxy group (1-butoxy group). Group) is preferred.
In the present invention, examples of the dialkylamino group include dialkylamino groups having about 1 to 6 carbon atoms. The alkyl chain portion of the dialkylamino group may be either a straight chain or a branched chain, and is preferably a straight chain. Examples of the dialkylamino group include a dimethylamino group and a diethylamino group, and among these, a dimethylamino group is preferable.

  In the present invention, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom and a chlorine atom are preferable.

  In the present invention, examples of the halogenated alkyl group include a halogenated alkyl group having 1 to 6 carbon atoms. The alkyl chain portion of the halogenated alkyl group may be either a straight chain or a branched chain, and is preferably a straight chain. The number of halogen atoms contained in the halogenated alkyl group may be one or two or more, but preferably one. Examples of the halogenated alkyl group include halogenated alkyl groups such as a fluorinated alkyl group, a chlorinated alkyl group, a brominated alkyl group, and an iodinated alkyl group having the alkyl groups listed as examples of the alkyl group. A methyl bromide group is preferred.

  In the present invention, the aromatic hydrocarbon group which may have a substituent means an aromatic hydrocarbon group having a substituent or an aromatic hydrocarbon group having no substituent. An aromatic hydrocarbon group means a monovalent substituent of an aromatic hydrocarbon. The number of carbon atoms in the aromatic hydrocarbon group is not particularly limited, but is preferably 3 or more and 15 or less, and more preferably 6 or more and 10 or less. The aromatic hydrocarbon group may be a group in which one and two or more aromatic rings (for example, an aromatic ring having 4 to 7 carbon atoms) are bonded (including condensation). Examples of the aromatic hydrocarbon group include a pentanyl group, a phenyl group, a heptyl group, a naphthyl group, an anthracyl group, and a phenanthryl group, and among these, a phenyl group and a naphthyl group are preferable.

  The heteroheterocyclic group which may have a substituent means a heteroheterocyclic group having a substituent or a heteroheterocyclic group having no substituent. The heterocyclic group means a heterocyclic group containing a hetero atom (for example, an oxygen atom, a nitrogen atom, a sulfur atom, etc.). In the case of a heteroheterocyclic group in which two or more rings are bonded (including fused), any group may contain a heteroatom. As the heterocyclic group, a heterocyclic group containing a nitrogen atom is preferable. The number of carbon atoms in the heterocyclic group is not particularly limited, but is preferably 3 or more and 15 or less, and more preferably 6 or more and 10 or less. Examples of heteroheterocyclic groups include pyrrolyl, imidazole, pyrazolyl, furyl, oxazolyl, thiophenyl, thiazolyl, isothiazolyl, etc. 5-membered ring groups; pyridyl, pyridazyl, pyrimidyl, pyrazyl , Piperidyl group, piperazyl group, morpholyl group, 6-membered ring group such as 2H-pyral group, 4H-pyral group; heteroatom-containing condensed ring groups such as pyrrolidyl group, pyridyl group, phthalimide group, and indole group. Of these, a heteroatom-containing fused ring group is preferred, and an indole group is preferred.

  Examples of the substituent that can be included in the aromatic hydrocarbon group and the hetero heterocyclic group include a halogen atom, an alkyl group, a cycloalkyl group, a halogenated alkyl group, an alkoxy group, a cycloalkyl group (such as a cyclopropyl group), an amino group, Mono or dialkylamino group, carboxyl group, alkoxycarbonyl group (such as ethoxycarbonyl group), alkanoyl group (such as acetyl group), aroyl group (such as benzoyl group), aralkyl group (such as benzyl group), aryl group (such as phenyl group) And aryloxy groups (such as phenoxy groups), heteroaryl groups (such as pyridyl groups), heteroaryloxy groups (such as pyridyloxy groups), heterocyclic groups (such as pyrrolidinyl groups), hydroxyl groups, nitro groups, and cyano groups. The Of these, alkyl groups, halogen atoms, and alkoxy groups are preferred.

  In the aromatic hydrocarbon group and heteroheterocyclic group which may have a substituent, the number of substituents may be 0 or more and 5 or less, but usually 0 or more and 3 or less, preferably 0 or more. 2 or less. In the case of having two or more substituents, each substituent may be the same substituent or different substituents.

  The bonding site of the aromatic hydrocarbon group and heteroheterocyclic group which may have a substituent to the skeleton of each general formula is not particularly limited.

  The substitution site on the aromatic hydrocarbon group and the heterocyclic group having a substituent is not particularly limited. For example, the substitution site of the phenyl group is preferably the 2-position and / or the 4-position.

  Examples of the aromatic hydrocarbon group which may have a substituent include 2-chlorophenyl group, 4-chlorophenyl group, 3,4-dichlorophenyl group, 2,4-dichlorophenyl group, 3,4-difluorophenyl group, 2 , 4-difluorophenyl group, 4-bromophenyl group, 4-trifluoromethoxyphenyl group, 4-toluyl group, 4-trifluoromethylphenyl group, 3-trifluoromethylphenyl group, 4-hydroxyphenyl group, 4- Methoxyphenyl group, 2-chloro-4-trifluoromethylphenyl group, 3-chloro-4-trifluoromethylphenyl group, 4-bromo-2-chlorophenyl group, biphenyl-4-yl group, (4-chlorophenyl) oxy 2-chlorophenyl group, 4- (1-butoxy) phenyl group, 4-phenoxyphenyl group, - and the like naphthyl groups. Among these, 4-chlorophenyl group, 2,4-dichlorophenyl group, 4- (1-butoxy) phenyl group, 4-dimethylaminophenyl group, 4-methylphenyl group, 2,4-difluorophenyl group, 4-phenoxy A phenyl group and a 1-naphthyl group are more preferable.

In the present invention, the 4-chlorophenyl group means a group represented by the following formula (a).

In the present invention, the 2,4-dichlorophenyl group means a group represented by the following formula (b).

In the present invention, 4- (1-butoxy) phenyl group means a group represented by the following formula (c).

In the present invention, the 2,4-difluorophenyl group means a group represented by the following formula (d).

In the present invention, the 4-phenoxyphenyl group means a group represented by the following formula (e).

In the present invention, the 4-dimethylamino group means a group represented by the following formula (f).

In the present invention, the 1-naphthyl group means a group represented by the following formula (g).

As an example of the heterocyclic group which may have a substituent, a 3-indole group represented by the following (h) is preferable.

In the present invention, the 4-methylphenyl group means a group represented by the following formula (i).

In the general formula (1-1), R ¹¹¹ is a hydrogen atom, a hydroxyl group or an alkyl group, R ¹¹² is an aromatic hydrocarbon group which may have an alkyl group or a substituent, and R ¹¹³ is a substituent. It is an aromatic hydrocarbon group that may have.

In general formula (1-1), ^R111 is a hydrogen atom, a hydroxyl group or an alkyl group, and preferably a hydroxyl group.

In General Formula (1-1), R ¹¹² is an aromatic hydrocarbon group which may have an alkyl group or a substituent, and is preferably an alkyl group or an aromatic hydrocarbon group having a substituent. Or it is more preferable that it is a phenyl group which has a substituent.

The alkyl group as R ¹¹² is preferably an alkyl group having 1 to 4 carbon atoms, and is preferably an alkyl group having a branched chain.

Examples of the substituent that the aromatic hydrocarbon group as R ¹¹² may have include a halogen atom, and a chlorine atom is preferable. The substitution site on the aromatic hydrocarbon group of R ¹¹² is preferably the 4-position. In the aromatic hydrocarbon group which may have a substituent as R ¹¹² , the number of substituents is not particularly limited, but is preferably one.

Preferred examples of R ¹¹² include a t-butyl group and a 4-chlorophenyl group.

In general formula (1-1), ^R113 is an aromatic hydrocarbon group that may have a substituent, preferably an aromatic hydrocarbon group having a substituent, and more preferably a phenyl group having a substituent. As the substituent that the aromatic hydrocarbon group for R ¹¹³ may have, an alkyl group or a dialkylamino group is preferable. The alkyl group and dialkylamino group preferably have 1 to 3 carbon atoms, and preferably has a linear structure. Preferable examples of the substituent that the aromatic hydrocarbon group for R ¹¹³ may have include a methyl group and a dialkylamino group. The substitution site on the aromatic hydrocarbon group for R ¹¹³ is preferably the 4-position. The number of substituents on the aromatic hydrocarbon group for R ¹¹³ is not particularly limited, but is preferably 1 to 2.

Preferred examples of R ¹¹³ include a 4-methylphenyl group and a 4-dimethylaminophenyl group.

In General Formula (1-2), R ¹²¹ is a hydrogen atom, an alkyl group, or an alkoxyalkyl group, R ¹²² is a phenyl group that may have a substituent, and R ¹²³ and R ¹²⁴ are each independently hydrogen. An atom or an alkyl group.

In general formula (1-2), R ¹²¹ is a hydrogen atom, an alkyl group or an alkoxyalkyl group, and is preferably an alkyl group or an alkoxyalkyl group. The alkyl group as R ¹²¹ is preferably an alkyl group having 1 to 4 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Preferable examples of the alkyl group as R ¹²¹ include an ethyl group, a methyl group, an n-propyl group, an n-butyl group, and a tert-butyl group. The alkoxyalkyl group as R ¹²¹ is preferably an alkoxyalkyl group having 1 to 4 carbon atoms, preferably an alkoxyalkyl group having 1 to 3 carbon atoms, A linear alkoxyalkyl group is preferred. Preferable examples of the alkoxyalkyl group as R ¹²¹ include a methoxymethyl group.

In General Formula (1-2), ^R122 is an aromatic hydrocarbon group that may have a substituent, preferably an aromatic hydrocarbon group having a substituent, and more preferably a phenyl group having a substituent. The substituent that the aromatic hydrocarbon group for R ¹²² may have is preferably an alkyl group, a halogen atom, or an alkoxy group. The alkyl group and alkoxy group preferably have 1 to 4 carbon atoms, and preferably has a linear structure. Preferable examples of the substituent that the aromatic hydrocarbon group for R ¹²² may have include a methyl group, a chlorine atom, and an n-butoxy group. The substitution site on the aromatic hydrocarbon group of R ¹²² is preferably the 2-position and / or the 4-position. The number of substituents on the aromatic hydrocarbon group for R ¹²² is not particularly limited, but is preferably 1 to 2.

Preferred examples of R ¹²² include a 4-chlorophenyl group, a 4-methylphenyl group, a 4-butoxyphenyl group (4-n-butoxyphenyl group), and a 2,4-dichlorophenyl group.

In general formula (1-2), ^R123 and ^R124 each independently represent a hydrogen atom or an alkyl group, and preferably both are hydrogen atoms.

In General Formula (1-3), R ¹³¹ is a hydrogen atom, an alkyl group, or an alkenyl group, R ¹³² is an alkyl group or an aromatic hydrocarbon group that may have a substituent, and R ¹³³ is a substituent. It is an aromatic hydrocarbon group that may have.

In General Formula (1-3), R ¹³¹ represents a hydrogen atom, an alkyl group, or an alkenyl group. The alkyl group or alkenyl group as R ¹²¹ is preferably an alkyl group having 1 to 3 carbon atoms, and is preferably linear. The alkyl group as R ¹³¹ is preferably a methyl group. The alkenyl group as R ¹³¹ is preferably a 3-propenyl group.

In General Formula (1-3), R ¹³² is an alkyl group or an aromatic hydrocarbon group that may have a substituent, preferably an aromatic hydrocarbon group that may have a substituent, and phenyl having a substituent. A phenyl group having no group or substituent is preferred. The substituent that the aromatic hydrocarbon group represented by R ¹³² may have is preferably a halogen atom, and more preferably a chlorine atom. The substitution site on the aromatic hydrocarbon group of R ¹³² is preferably at the 4-position. The number of substituents on the aromatic hydrocarbon group for R ¹³² is not particularly limited, but is preferably 0 to 1. Preferable examples of R ¹³² include 4-chlorophenyl group and phenyl group.

In general formula (1-3), ^R133 is an aromatic hydrocarbon group that may have a substituent, preferably an aromatic hydrocarbon group having a substituent, and more preferably a phenyl group having a substituent. The substituent that the aromatic hydrocarbon group for R ¹³³ may have is preferably a halogen atom, and more preferably a chlorine atom. The substitution site on the aromatic hydrocarbon group of R ¹³³ is preferably at the 4-position. The number of substituents on the aromatic hydrocarbon group for R ¹³³ is not particularly limited, but is preferably one. A preferred example of R ¹³³ includes a 4-chlorophenyl group.

In General Formula (2-1), ^R211 is an aromatic hydrocarbon group that may have a substituent or a heteroheterocyclic group that may have a substituent, m is 1 or 2, and n is 0 Or 1, and A is a nitrogen atom or —CH—.

^R211 is an aromatic hydrocarbon group which may have a substituent or a heterocyclic group which may have a substituent.

Examples of the substituent that the aromatic hydrocarbon group as R ²¹¹ and the hetero heterocyclic ring may have include a phenyloxy group. The aromatic hydrocarbon group or heteroheterocycle may be an aromatic hydrocarbon group or heteroheterocycle containing two or more aromatic rings (two or more aromatic rings may be condensed with each other). preferable. As the aromatic hydrocarbon group and ^{heteroheterocycle} as R ²¹¹ , a phenyl group, a naphthyl group and an indole group are preferable, and each may or may not have a substituent.

Preferred examples of R ²¹¹ is 4-phenoxyphenyl group, a naphthyl group, and indole group.

  In general formula (2-1), m is 1 or 2, and n is 0 or 1. When m is 2, n is preferably 0. When m is 1, n may be 0 or 1.

In general formula (2-1), A is a nitrogen atom or -CH-. That is, the compound represented by the general formula (1) is a compound having a triazole ring in its structure when A is a nitrogen atom, and a compound having an imidazole ring in its structure when A is —CH ₂ —. It is.

As a preferable combination of the substituents in the general formula (2-1), R ²¹¹ is a naphthyl group, m is 2, n is 0, and A is a nitrogen atom; R ²¹¹ is a naphthyl group. A combination in which m is 2, n is 0, and A is —CH—; R ²¹¹ is a 4-phenoxyphenyl group, m is 1, n is 1, and A is preferably the combination is a nitrogen atom; R ²¹¹ is a 3-indole group, m is 1, n is 0, a is preferably a combination of a nitrogen atom, and the like.

In General Formula (2-2), R ²²¹ is a hydrogen atom, an alkyl group, or a halogenated alkyl group, R ²²² is a hydrogen atom, an alkyl group, or a halogen atom, and p is an integer of 1 to 5.

R ²²¹ is a hydrogen atom, an alkyl group or a halogenated alkyl group, preferably a halogenated alkyl group. The number of carbon atoms in the alkyl portion of the halogenated alkyl group is preferably one. The alkyl part of the halogenated alkyl group is preferably linear. The number of halogen atoms contained in the halogenated alkyl group may be one or more. In a halogenated alkyl group containing two or more halogen atoms, two or more halogen atoms may contain different halogen atoms or two or more of the same halogen atoms, but preferably one. . A preferred example of R ²²¹ is a methyl bromide group.

In General Formula (2-2), R ²²² is a hydrogen atom, an alkyl group, or a halogen atom, and is preferably a halogen atom. P is an integer of 1 to 5, preferably 2, which is the number of the substituent R ²²² . When p is 2 or more, two or more R ²²² may be different types of substituents or the same substituent, but is preferably the same substituent. Of these, both are preferably fluorine atoms. The bonding site of R ²²² to the skeleton of the general formula (2-2) is not particularly limited, but when p is 2, the binding of R ²²² is represented by the following general formula (2-20). it is coupled (.2 one R ²²² defined are as defined above medium equation (2-20) R ²²² may be the same or different.) are preferred.

  The compounds represented by the general formulas (1-1) to (1-3), the general formula (2-1), and the general formula (2-2) may have one or more asymmetric carbons. is there. That is, the compounds represented by the general formulas (1-1) to (1-3), the general formula (2-1), and the general formula (2-2) are purely optically active substances based on an asymmetric carbon, Any of a diastereoisomer, a mixture of arbitrary isomers (for example, a mixture of two or more diastereoisomers), a racemate, and the like may be used.

  The form of the salt of the compound represented by General Formulas (1-1) to (1-3), General Formula (2-1), and General Formula (2-2) is not particularly limited, and depends on the type of substituent. Examples thereof include acid addition salts. The type of salt is not particularly limited, and salts with mineral acids such as hydrochloric acid and sulfuric acid, salts with organic acids such as p-toluenesulfonic acid, methanesulfonic acid and tartaric acid, metals such as sodium salt, potassium salt and calcium salt Examples thereof include a salt, an ammonium salt, a salt with an organic amine such as triethylamine, and a salt with an amino acid such as glycine.

  Examples of the compound represented by the general formula (1-1) or a salt thereof include the following.

1-chlorophenyl-3- (4-methylphenyl) -2- (1,2,4-triazoyl) -2-propen-1-ol (hereinafter referred to as MA73; structure represented by formula (1-11) Have

1- (2,2-dimethylethyl) -3- (4-dimethylaminophenyl) -2- (1,2,4-triazoyl) -2-propen-1-ol (hereinafter referred to as MA65. Formula ( 1-12).

  Examples of the compound represented by the general formula (1-2) or a salt thereof include the following.

1-[[2- (4-Chlorophenyl) -4-propyl-1,3-dioxolan-2-yl] methyl] -1H-1,2,4-triazole (hereinafter referred to as SEA10. Formula (1- 21).

1-[[2- (4-Chlorophenyl) -4-ethyl-1,3-dioxolan-2-yl] methyl] -1H-1,2,4-triazole (hereinafter referred to as SEA13. Formula (1- 22).

1-[[2- (4-Methylphenyl) -4-propyl-1,3-dioxolan-2-yl] methyl] -1H-1,2,4-triazole (hereinafter referred to as SAR33. Formula (1) -23).)

4RS-1-[[4-methyl-2- (4- (1-butoxy) phenyl) -1,3-dioxolan-2-yl] methyl] -1H-1,2,4-triazole (hereinafter referred to as KSR179) (It has a structure represented by Formula (1-24).)

1-[[4-methoxymethyl-2- (2,4-dichlorophenyl) -1,3-dioxolan-2-yl] methyl] -1H-1,2,4-triazole (hereinafter referred to as KSR90. Formula) (It has a structure represented by (1-25).)

  Examples of the compound represented by the general formula (1-3) or a salt thereof include the following.

-3- (4-Chlorophenyl) -1-phenyl-2- (1,2,4-triazoyl) -propan-1-ol (hereinafter referred to as MA31. It has a structure represented by Formula (1-31). )

4- (4-Chlorophenyl) -2-phenyl-3- (1,2,4-triazoyl) -butan-2-ol (hereinafter referred to as MA87. It has a structure represented by Formula (1-32). )

2,4-di (4-chlorophenyl) -3- (1,2,4-triazoyl) -butan-2-ol (hereinafter referred to as MA88, having a structure represented by the formula (1-33))

6- (4-chlorophenyl) -4-phenyl-5- (1,2,4-triazoyl) -1-hexen-4-ol (hereinafter referred to as SEA22. The structure represented by the formula (1-34) Have)

  Examples of the compound represented by the general formula (2-1) or a salt thereof include the following.

1- (1-naphthyl) -2- (1H-1,2,4-triazol-1-yl) -ethane (hereinafter referred to as KSR236, having a structure represented by formula (2-11))

1- (1-naphthyl) -2- (1H-imidazol-1-yl) -ethane (hereinafter referred to as KSR233, having a structure represented by formula (2-12))

1- (3-Indolyl) -2- (1H-1,2,4-triazol-1-yl) -ethane (hereinafter referred to as KSR221, having a structure represented by Formula (2-13))

1- (4-phenoxyphenyl)-(1H-1,2,4-triazol-1-yl) -methyl ketone (hereinafter referred to as KSR122, having a structure represented by formula (2-14))

  Examples of the compound represented by the general formula (2-2) or a salt thereof include the following.

2,4-difluorophenyl-bromomethyl ketone (hereinafter referred to as KSR51, having a structure represented by formula (2-21))

  The origin of the compound represented by the general formulas (1-1) to (1-3), the general formula (2-1), and the general formula (2-2) or a salt thereof is not particularly limited. For example, those synthesized by a chemical reaction can be used. Examples of the synthesis method include Japanese Patent Application Laid-Open No. 2000-53657, Japanese Patent No. 3762949, Zeitschifffur Natureforsung, 44c, pp. The method described in literatures, such as 85-96, 1989, is illustrated.

  The cell differentiation promoting agent of the present invention contains a compound represented by the general formulas (1-1) to (1-3), the general formula (2-1), and the general formula (2-2) or a salt thereof. That is, the cell differentiation promoting agent includes a compound represented by the general formula (1-1), a salt of the compound represented by the general formula (1-1), a compound represented by the general formula (1-2), and a general formula. A salt of the compound represented by (1-2), a compound represented by the general formula (1-3), a salt of a compound represented by the general formula (1-3), and a salt represented by the general formula (2-1) Selected from the compounds represented by formula (2-1), the compound represented by formula (2-2), and the salt of the compound represented by formula (2-2). 1 type is contained individually or contains 2 or more types.

  Examples of cells include plant cells. The cell differentiation promoting agent of the present invention has the effect of significantly promoting the differentiation of plant cells into root cells. Therefore, the cell differentiation promoting agent of the present invention is useful as an adventitious root formation promoting agent.

  The plant adventitious root formation promoter of the present invention comprises a compound represented by the general formulas (1-1) to (1-3), the general formula (2-1), and the general formula (2-2) or a salt thereof. As long as it does not contradict the purpose of the present invention, it may contain other components (for example, other adventitious root formation accelerators) as necessary.

  The adventitious root formation promoter of the present invention exhibits an adventitious root formation promoting effect by being present when cultivating plants.

  The kind of plant is not particularly limited. The plant can be classified into a woody plant and a herbaceous plant, but in the present invention, it can be applied to any of these, preferably applied to a woody plant, and has a lower rooting ability than a herbaceous plant. More preferably, it is applied to a woody plant. Examples of woody plants include Eucalyptus plants, Pinus plants, Cryptomeria plants (such as Cryptomeria japonica), Prunus plants (Prunus spp.), And Ume. (Prunus mume), Prunus tomentosa, etc., Avocado plant, Mangofera plant (Mangofera indica, etc.), Acacia plant, Prunus genus, Ms. Quercus plants (such as Quercus actissima), grapes (Vitis) plants, apples (Malus) plants, roses (Ros) ) Plants, Camellia plants (such as Camellia sinensis), Jacaranda plants (such as Jacaranda mimosifolia), crocodiles (Persea) plants (such as Persera america) (Pyrus) plants (such as pear (Pyrus serotina Rehder, Pyrus pyrifolia)), sandalwood genus (Santalum) plant (sandalwood, etc.) are exemplified. Of these, when applied to plants such as eucalyptus, pine, cedar, cherry, mango, avocado, acacia, bayberry, squirrel, grapes, apples, roses, camellia, tea, ume, eusloume, jacaranta, and the like, It can be effective. Among them, Eucalyptus plants, Pinus plants, Sugi plants, Camellia plants, Mango plants, Vanilla plants, and Eucalyptus, pine, Sugi, Cha, mango and avocado, which are known to be difficult to root, are more preferable, and Eucalyptus is more preferable. Further preferred.

As the eucalyptus, eucalyptus known to be difficult to root is preferable, and eucalyptus globulus, round leaf eucalyptus and the like are more preferable.
Examples of herbaceous plants that can be applied in the present invention include plants belonging to families such as Brassicaceae, Eggplant, Gramineae, and Leguminosae, but are not limited to these plants. Thus, in the present invention, it can be generally applied to vegetables such as solanaceous plants as well as food-producing plants such as cereals such as rice and wheat, beans, and corn. I have great expectations. Among plants belonging to families such as Brassicaceae, Eggplant Family, Gramineae, and Leguminosae, Arabidopsis thaliana, tobacco (Nicotiana tabacum), rice (Oryza sativa), Miyakogusa (Lotus cornicula sp. Model). Since it is widely used as a plant, it can be expected to contribute to the development of research and development.

  The plant may be a part or the whole of the plant body, but is usually a part of the plant body, preferably a shoot, in that it is expected to form adventitious roots.

  Shoots refer to all tissues that have rooting ability. Examples of the tissue include tissues that are part of organs such as branches, stems, apical buds, buds, adventitious buds, leaves, cotyledons, hypocotyls, adventitious embryos, and shoot primordia. The origin of the shoot is not particularly limited, and it may be obtained from a plant individual growing in a greenhouse or outdoors, may be a cultured tissue obtained by a tissue culture method, or may be a natural plant body. It may be a departmental 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.

  The multi-bud can be derived by cutting shoots such as apical buds and buds from a plant to which the present invention is applied to produce a clonal seedling, and tissue-cultivating them. In order to form a multi-bud by aseptically culturing an organ collected from a mother plant, it can be formed according to the method and conditions described in JP-A-8-228621. The method and conditions are generally as follows. First, bud tissues such as apical buds and acupuncture buds are collected from a plant as a material, and the collected tissues are sodium hypochlorite aqueous solution having an effective chlorine content of about 0.5% to about 4% or an effective chlorine content of about 5%. Surface sterilization is performed by dipping in a 10% to about 15% aqueous hydrogen peroxide solution 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, sprouts), the medium is sucrose 1 to 5% by weight, and the plant hormone is benzyladenine (hereinafter abbreviated as BA) of about 0.02 mg / l to about 1 mg. / L or less, Murashigesukuog (hereinafter abbreviated as MS) medium containing about 0.2% to about 0.3% by weight of gellan gum or about 0.5% to about 1% by weight of agar or ammonium nitrate of MS medium It is preferable to use a modified MS medium in which the components and the potassium nitrate component 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.

  On the other hand, cutting ears may be used as shoots. Usually, the effect is exhibited by administering an adventitious root formation promoter to the cuttings. 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 usually use branches such as green branches and mature branches, and the cuttings in the case of herbaceous plants usually use leaves and buds, but are not limited thereto.

  The method for cultivating a plant in the presence of the adventitious root formation promoter of the present invention is not particularly limited, and can be appropriately selected from the type, site, state, etc. of the plant. Specifically, a method of cultivating a plant (preferably shoot) in a rooting medium containing an adventitious root formation promoter; a method of bringing a solution containing an adventitious root formation promoter into contact with a plant (preferably shoot) is exemplified. . When the cultured tissue obtained by the tissue culture method is used as the shoot, the former is preferable, and when the cutting head is used as the shoot, both the former and the latter are preferable. Of course, it is possible to employ a combination of the above-described two methods, that is, a method of contacting a plant with a solution containing an adventitious root formation promoter while cultivating the plant in a rooting medium containing an adventitious root formation promoter. It is.

  When a plant is cultured in a rooting medium containing an adventitious root formation promoter, the concentration of the adventitious root formation accelerator in the rooting medium is preferably about 0.01 μM or more and about 2000 μM or less, more preferably about 0.01 μM or more. It is about 500 μM or less, particularly preferably about 0.1 μM or more and about 150 μM or less.

  When culturing in the rooting medium, a support can be used as described later. When using a support with low adsorption of active ingredients such as a porous molded article as the support, the amount of adventitious root formation promoter added in the rooting medium is preferably about 0.01 μM or more and about 100 μM or less, more preferably It is about 0.05 μM or more and about 50 μM or less, particularly preferably about 0.1 μM or more and about 10 μM or less.

  The method of bringing a solution containing an adventitious root formation promoter (adventitious root formation accelerator solution) into contact with a plant (preferably shoot) is not particularly limited, and may be appropriately selected based on the type, site, state, cultivation method, and the like of the plant. Examples of the method include a method of directly spraying an adventitious root formation accelerator solution onto a shoot and a method of infiltrating a support with an adventitious root formation accelerator solution.

  The adventitious root formation accelerator solution can be prepared by dissolving an adventitious root formation accelerator in an appropriate solvent (for example, water). Examples of water include deionized water, distilled water, reverse osmosis water, and tap water, and any of them can be used. The concentration of the adventitious root formation accelerator in the adventitious root formation accelerator solution is preferably about 0.01 μM or more and about 2000 μM or less, more preferably about 0.05 μM or more and about 500 μM or less, and about 0.1 μM or more and about 150 μM. Even more preferably:

  When the adventitious root formation promoter solution is sprayed directly on plants (preferably shoots), the adventitious root formation promoter solution may be sprayed on a part or the whole of the plant in the form of a mist using a spray or the like. The application amount of the adventitious root formation accelerator solution cannot be defined unconditionally depending on the concentration of the adventitious root formation accelerator in the adventitious root formation accelerator solution, but generally about 0.5 ml or more and about 5.0 ml per shoot. The following is preferable, and about 1.0 ml or more and about 3.0 ml or less is more preferable. The number of spraying may be one time or two or more times, but is preferably sprayed at least at the start of cultivation. Furthermore, according to cultivation conditions, you may spray by addition suitably (for example, every several days (2 days-3 days)) during a cultivation period.

  As a method of wetting the support with the adventitious root formation accelerator solution, a method of spraying the adventitious root formation accelerator solution from the upper part of the support, a method of placing the support in a container filled with the adventitious root formation accelerator solution and irrigating from the bottom surface Etc. are exemplified. When watering from the upper part of the support, the amount of water sprayed from the upper part is preferably about 1.0 ml or more and about 30 ml or less, more preferably about 5.0 ml or more and about 10 ml or less per one plant (preferably shoot). When irrigating from the bottom, the adventitious root formation promoter solution may be wetted substantially uniformly on the support. When the support is wetted with the adventitious root formation accelerator solution, a rooting medium may be separately prepared in addition to the adventitious root formation accelerator solution, and the support may be wetted with both.

In the present invention, the rooting medium means a medium used for rooting from plants (preferably shoots). 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, because when roots and elongation of healthy roots are promoted when added to a medium and shoots are cultured. This is presumably because the silver ions derived from STS take the form of silver thiosulfate ions in the medium and are negatively charged. The concentration of silver ions added to the rooting medium depends on the type of the 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. More preferred is about 6 μM or less.

  On the other hand, known antioxidants such as ascorbic acid and sulfite can be used as the antioxidant. Among them, ascorbic acid is preferable as an antioxidant used in the present invention because of its low persistence in the medium. The concentration of the antioxidant added to the rooting medium is preferably about 5 mg / l or more and about 200 mg / l or less, more preferably about 20 mg / l or more and about 100 mg / l or less.

  The rooting medium used in the present invention may contain components such as inorganic components, carbon sources, vitamins, amino acids, and plant hormones in addition to the above components.

  Inorganic components include nitrogen, phosphorus, potassium, sulfur, calcium, magnesium, iron, manganese, zinc, boron, molybdenum, chlorine, iodine, cobalt and other inorganic salts containing one or more selected from these elements. Illustrated. Examples of the inorganic salt 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, and zinc sulfate. Water of one or more inorganic salts selected from inorganic salts such as copper sulfate, sodium sulfate, calcium chloride, magnesium chloride, boric acid, molybdenum trioxide, sodium molybdate, potassium iodide, cobalt chloride, etc. Japanese products are listed. As an inorganic component, it can select from 1 type from said example, or can use it in combination of 2 or more type.

  The rooting medium used in the present invention preferably contains nitrogen, phosphorus, and potassium as essential elements. Therefore, among the examples of the inorganic components, nitrogen, phosphorus, potassium, inorganic salts containing nitrogen, inorganic salts containing phosphorus, and inorganic salts containing potassium are preferable, and inorganic salts containing nitrogen, phosphorus, potassium, and nitrogen are more preferable. preferable. The inorganic component is preferably added so that the concentration in the rooting medium is about 0.1 μM or more and about 100 mM or less, and it is added so that the concentration is about 1 μM or more and about 100 mM or less. More preferred. In the case of a combination of two or more, it is preferably added so as to be about 0.1 μM or more and about 100 mM or less, and more preferably about 1 μM or more and about 100 mM or less.

  As a carbon source, compounds such as carbohydrates such as sucrose and derivatives thereof; organic acids such as fatty acids; primary alcohols such as ethanol can be used. As the carbon source, one type can be selected from the above examples, or two or more types can be used in combination. The carbon source is preferably added to the rooting medium so as to be about 1 g / l or more and about 100 g / l or less, and more preferably about 10 g / l or more and about 100 g / l or less. 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 a medium supplemented with these is used, 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). As vitamins, one can be selected from the above examples, or two or more can be used in combination. It is preferable to add vitamins so that the concentration in the rooting medium is about 0.01 mg / l or more and about 200 mg / l or less in the rooting medium in the case of one kind. More preferably, it is added so as to be not less than / l and not more than about 100 mg / l. In the case of a combination of two or more, it is preferable to add about 0.01 mg / l or more and about 150 mg / l or less in the rooting medium, respectively, and about 0.02 mg / l or more and about 100 mg / l or less. More preferably, it is added.

  Examples of amino acids include glycine, alanine, glutamic acid, cysteine, phenylalanine, and lysine. As amino acids, one type can be selected from the above examples, or two or more types can be used in combination. The amino acids are preferably added so that the concentration in the rooting medium is about 0.1 mg / l or more and about 1000 mg / l or less in the rooting medium in the case of one kind. In the case of a combination, it is preferable to add about 0.2 mg / l to about 1000 mg / l in the rooting medium.

  Moreover, as plant hormones, for example, auxins and / or cytokinins can be used. 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 or more selected from the above or a combination of two or more may be used. Examples of cytokinins include benzyladenine (BA), kinetin, zeatin, and derivatives thereof, and one or more selected from these can be used in combination. As plant hormones, only auxins, only cytokinins, or a combination of both auxins and cytokinins can be used. When one kind of plant hormone is used, it is preferably added to the rooting medium so as to be about 0.01 mg / l or more and about 10 mg / l or less, and about 0.02 mg / l or more and about 10 mg / l. It is more preferable to add so that it may become 1 or less. When two or more kinds are used, it is preferably added to the rooting medium so as to be about 0.01 mg / l or more and about 10 mg / l or less, and about 0.02 mg / l or more and about 10 mg / l or less. More preferably, it is added.

  In the present invention, an adventitious root formation promoter is added to a medium known as a plant tissue culture medium as needed, and further, silver ions and / or antioxidants are added, and a carbon source, Plant hormones may be appropriately added and used as a rooting medium. Examples of such a plant tissue culture medium include MS medium, Rinsmeier Skoog medium, white medium, Gamborg B-5 medium, and niche niche medium. Among them, MS medium and Gamborg B-5 medium are preferable. These media can be appropriately diluted as necessary.

  The rooting medium may be either a liquid medium or a solid medium, but the liquid medium is preferable in terms of working efficiency and less damage to the roots during transplantation. The liquid medium can be prepared by mixing the medium composition. Further, the solid medium can be used by mixing and preparing the medium composition in the same manner as the liquid medium, or by solidifying with a solidifying agent such as agar or gellan gum after adjustment. The amount of the solidifying agent added to the medium varies depending on conditions such as the type of the solidifying agent and the composition of the medium. When the solidifying agent is agar, the amount added is preferably 0.5% by weight or more and 1% by weight or less. When the solidifying agent is gellan gum, the amount added is preferably 0.2% by weight or more and 0.3% by weight or less.

  The method of inserting a plant (preferably shoot) into the rooting medium can be appropriately selected depending on the culture conditions such as the type of the medium. When the rooting medium is a solid medium, the root of the shoot may be directly inserted into the rooting medium and cultured. On the other hand, in the case where the rooting medium is a liquid medium, for example, the base of the shoot may be inserted and cultured in a support medium described later wetted with a rooting medium. In order to improve the rooting rate, it is also preferable to apply a physical stimulus such as scratching the base of the shoot when it is inserted into the rooting medium. The base of the shoot means an area where the root is formed at one end of the shoot (opposite to the end where the leaf is formed). When using a multi-bud as a shoot, the base of the shoot is a region having a cut surface (generated when dividing the multi-shoot). The size (size, shape, etc.) of the scratch on the base of the chute is not particularly limited. For example, it is preferable that the base of the shoot as a shoot (the above-mentioned cut surface) is scratched so as to have a cross shape when viewed from the front. When scratching, tools such as scissors and a knife can be used.

  In the present invention, the support is a support for supporting a plant (preferably a shoot). In the case of using a solid medium among rooting media, a support is not necessary, but in other cases, a support is usually used.

  The support is preferably one that can be held in a state where the shoot is pointed during the cultivation period. In addition, when a liquid rooting medium is used for cultivation, it is usually used by infiltrating a support. Therefore, the support is preferably one that can be infiltrated with a liquid, and among them, one that can be wetted substantially uniformly by a liquid culture medium containing an adventitious root formation accelerator solution or an adventitious root formation accelerator is preferable. When a liquid medium is used as a rooting medium, a liquid medium (not containing an adventitious root formation accelerator solution) and an adventitious root formation accelerator solution may be added separately to the support, or a pre-prepared adventitious root. A liquid medium containing a formation promoter may be added to the support. A conventional support can 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; porous molded products such as foamed phenol resin and rock wool. be able to. The rooting bed can be prepared by placing such a support in a culture vessel and moistening it with an adventitious root formation accelerator solution or a liquid medium containing an adventitious root formation accelerator. 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, a culture vessel for containing a rooting medium or a support can be used. 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 is preferable. By using a sealed culture vessel, the sprayed adventitious root formation accelerator solution can be retained. Moreover, it becomes easy to maintain the humidity of the environment surrounding the shoot and the clonal seedling to be formed.

  When a branch is used as the chute, it is preferable to use a sealed culture container as the culture container. This makes it easy to place the chute 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. Further, the pore diameter of the membrane is not particularly limited, and examples thereof include those having a thickness of about 0.1 μm to about 1 μm.

The cultivation conditions for cultivating the plant are not particularly limited as long as it is a condition that can be rooted from the plant. Although it is difficult to unconditionally define the cultivation conditions depending on the type of plant, site, state, type of rooting medium, etc., for example, the temperature is more preferably about 23 ° C. or higher and about 28 ° C. or lower. Light intensity is expressed as a photosynthetic photon flux density of about 10 .mu.mol / m is preferably from ² / s or more to about 1000 micro mol / m ² / s, about 50 [mu] mol / m ² / s or more to about 500 [mu] mol / m ² / s The following is more preferable. In either case, rooting from the shoot is usually observed within about 2 to 5 weeks.

  Cultivation is preferably performed under light irradiation containing a wavelength component of about 650 nm or more and about 670 nm or less and a wavelength component of about 450 nm or more and about 470 nm or less in a ratio of 9: 1 to 7: 3. It is more preferable to carry out under the irradiation of the light included in the ratio of 9: 1 to 8: 2. By irradiating with light containing such a wavelength component, rooting from a plant (preferably a shoot) can be further promoted.

  Furthermore, it is preferable to supply carbon dioxide gas in the cultivation environment so that it is usually 300 ppm to 2000 ppm, preferably 800 ppm to 1500 ppm. Control of the supply amount of carbon dioxide gas can be performed by placing a culture vessel or the like having a carbon dioxide permeable membrane in the opening in an equipment such as an artificial weather device whose carbon dioxide concentration is adjusted to the above range. .

  The humidity is preferably 80% or more, and more preferably 85% or more. With this humidity, rooting from plants can be promoted. There is no particular limitation on the upper limit.

  On the other hand, when using cuttings as a chute, 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.

  As described above, adventitious roots can be rooted from plants using the adventitious root formation promoter of the present invention. A plant in which adventitious roots are rooted is usually called a clone seedling. Continue cultivation for a certain period of time using the adventitious root formation promoter of the present invention (depending on conditions such as plant type, part, and state, but in the case of eucalyptus, for example, about 10 days to 90 days or less) to enhance the roots. After that, it can be transplanted and grown in a soil such as a seedling container or a nursery to make a seedling that can be used for a predetermined purpose such as afforestation. Conditions such as temperature and light intensity for growing soil and seedlings may be appropriately set so as to be suitable for a plant to be rooted. When shoots derived from cultured tissues (eg adventitious buds, shoot primordia) are rooted, it is usually necessary to go through an acclimatization process before transplanting to a soil such as a seedling container or nursery field. There is.

  As described above, the cell differentiation promoter of the present invention is useful as an adventitious root formation promoter. Since the adventitious root formation promoting action in the present invention is presumed to be based on the action described in the lower part, the general formula (1-1), the general formula (1-2), the general formula (1-3), the general formula ( The compound represented by either 2-1) and general formula (2-2) or a salt thereof is also useful as an active ingredient of a plant hormone activity promoter. Furthermore, a plant hormone activity promoter can be rephrased as a plant hormone synthesis promoter, a plant hormone metabolism (degradation) inhibitor, or a plant hormone metabolism (degradation) -related P450 gene expression inhibitor.

  A plant hormone that can be a target of a plant hormone activity promoter is a substance that can be produced by plants among plant growth regulators and that can regulate physiological processes of plants even at low concentrations. Examples of plant hormones include, but are not limited to, auxins, gibberellins, cytokinins, abscisic acid, ethylene, brassinosteroids and the like. For example, among the adventitious root formation promoters of the present invention, it is predicted that among plant hormones, those that promote the activity of plant hormones involved in adventitious root formation in plants are also included. A representative of such hormones is auxins. Examples of auxins are as described above. A method for confirming whether a certain compound has a plant hormone activity promoting action is not particularly limited. For example, when the plant hormone is an auxin, it is confirmed that it has a β-glucuronidase (GUS) activity by actually acting on a genetically modified plant (eg, Arabidopsis thaliana) into which an auxin-inducible reporter gene (eg, DR5 :: GUS) has been introduced. Thus, the action of promoting the activity of auxins can be confirmed.

[Action]
In the present invention, a plant shoot can be rooted from the shoot by cultivating it in the presence of an adventitious root formation promoter. The reason is guessed as follows.

  A compound represented by any one of General Formula (1-1), General Formula (1-2), General Formula (1-3), General Formula (2-1), and General Formula (2-2) or a salt thereof Is considered to have a P450 gene inhibitory action, and its adventitious root formation promoting effect is due to some form of auxin such as promotion of auxin activity or synthesis in plant tissues, or inhibition of metabolism (degradation) of auxins. It is thought to be involved in work. Examples of auxins are as described above. Here, the P450 gene is a gene encoding cytochrome P450. Cytochrome P450 is a group of heme proteins widely distributed in the living world from microorganisms to plants and animals, and shows a characteristic absorption spectrum having a maximum at 450 nm in combination with carbon monoxide in a reduced form. Cytochrome P450 has monooxygenase-type oxygenase activity, but differs in the substrate specificity of the catalyzed reaction. However, as a result of a comparison between the primary structure and the higher-order structure of proteins, it is considered to be a diversified gene family that is differentiated from a common ancestral gene during the process of biological evolution.

  It is known that cytochrome P450 has a very large number of molecular species. The number of P450 genes reported in higher plants is 273 in Arabidopsis thaliana and 458 in rice (Oryza sativa) after the completion of the genome project. When these are compared with 83 nematodes (Caenorhabditis elegans), 89 drosophila (Drosophila melanogaster), 57 humans (Homo sapiens), it can be seen that the number of P450s in higher plants is remarkably high.

  The P450 gene has many functions in plants such as secondary metabolism and herbicide metabolism, as well as growth differentiation control. There are P450 genes involved in each function, and P450 genes involved in the metabolism of auxins. Is also known.

〔Compound〕
The present invention provides a compound represented by the general formula (2-1) and a compound represented by the general formula (2-2).

(In the general formula (2-1), R ²¹¹ is an aromatic hydrocarbon group which may have a substituent or a heterocyclic group which may have a substituent, m is 1 or 2, and n is 0 or 1 and A is a nitrogen atom or —CH—.)
(In the general formula (2-2), R ²²¹ is a hydrogen atom, an alkyl group or a halogenated alkyl group, R ²²² is a hydrogen atom, an alkyl group or a halogen atom, and p is an integer of 1 to 5. )

  The substituent in each general formula and the compound represented by each general formula are the same as those described in the explanation of the cell differentiation promoting agent.

  Hereinafter, the present invention will be described in more detail with reference to examples.

[Examples 1 to 12]
Eucalyptus globulus (hereinafter simply abbreviated as E. globulus) was used as a material for cuttings. That is, from the harvested mother tree, a length of 5 to 20 cm, a node having 1 to 3 nodes, and a leaf having about 2 to 6 leaves were cut out to prepare cuttings.

The base of the cuttings thus obtained was divided into MA31 (Example 1), MA87 (Example 2), MA88 (Example 3), KSR90 (Example 4), KSR179 (1: cis body) (Example 5), KSR179 (2: Trans form) (Example 6), SEA10 (Example 7), SEA13 (Example 8), SEA22 (Example 9), SAR33 (Example 10), MA65 (Example 11), MA73 ( Example 12) (synthesized according to the methods described in JP-A No. 2000-53657, Japanese Patent No. 3762949, Zeitschifffur Naturforschung, 44c, pp. 85-96, 1989, respectively) source as _{STS (AgS 4 O 6) 5μM} , ascorbic acid 50 mg / l as antioxidant, and a plant hormone 4 times diluted MS medium (composition: ammonium nitrate 412.5 mg / l, potassium nitrate 475 mg / l, potassium dihydrogen phosphate 42.52 mg / l, potassium iodide 0.21 mg / l, This medium is not added with a carbon source.) Inserted into a porous support made of foamed phenolic resin (made by Smithers Oasis, trade name: Oasis) wetted with a medium, carbon dioxide concentration 1000 ppm, temperature 25 ° C., 650 Incubate for 2 months under irradiation with red light having a photosynthesis effective photon flux density of 51.3 μmol / m ² / S, containing a wavelength component of ˜670 nm and a wavelength component of 450 to 470 nm at a ratio of 8.2: 1.8. went. At this time, as the culture vessel, a cube having a maximum dimension of 10 to 11.5 cm in length, 10 to 11.5 cm in width, and 10.0 cm in height and having a slightly projecting body portion was used. The top surface of the culture vessel is provided with one circular opening to which a polytetrafluoroethylene film (made by Millipore, trade name: Milliceal) having a pore diameter of 0.45 μm is attached. The concentration of carbon dioxide in the culture vessel is the concentration (about 1000 ppm) permeated from the membrane at the opening of the culture container because the carbon dioxide outside the culture vessel permeates through the membrane at the opening of the culture vessel. there were. Irradiation of the red light irradiation to the culture vessel was performed using a product name: CCFL light source unit and a manufacturer name: Nippon Medical Instruments Co., Ltd. as a light irradiation device. Moreover, the humidity in the culture container was adjusted by sealing the culture container with parafilm.

  16 cuttings were inserted per culture container. The rooting rate was calculated from the number of cuttings tested and the number of shoots rooted after culturing for 2 months (number of roots). The results are shown in Table 1-1 and FIG. Moreover, the state of rooting after 2 months culture of the sample cultivated by adding MA65 is shown in FIG.

[Comparative Example 1]
Culturing was carried out in the same manner as in Example 1 except that a medium not containing adventitious root formation promoter was used. The results are shown in Table 1-1 and FIG. Moreover, the state of rooting after 2 months culture | cultivation of the sample cultivated without the compound addition is shown in FIG.

[Comparative Examples 2 to 5]
Instead of the adventitious root formation accelerator of the present invention, brassnazole (Brz) 1.0 μM (Comparative Example 2), pacloputrazole 1.0 μM (Comparative Example 3), pacloputrazole 0.1 μM (Comparative Example 4), Culturing was performed in the same manner as in Example 1 except that a medium supplemented with 5.0 μM pacloputrazole (Comparative Example 5) was used. The results are shown in Table 1-2 and FIG.

  As is clear from Table 1-1, Table 1-2, and FIG. 1, in all cases, the rooting rate of eucalyptus was remarkably increased as compared with the case of no addition (FIG. 2-1). These rooting rates were higher than those of Brz and paclobutrazol which were conventionally known as rooting promoters. In particular, the rooting rate when SEA13, MA65 (FIG. 2-2) is used is around 90%, and when MA31, MA87, MA88, KSR179 (transformer), SEA10, MA73 is used, nearly 50%. All of them showed a remarkable rooting rate.

[Example 13]
Culturing was performed in the same manner as in Example 11 except that round leaf eucalyptus was used as a material for cuttings. The results are shown in Table 2 and FIG.

[Comparative Example 6]
Culturing was carried out in the same manner as in Example 13 except that a medium not containing an adventitious root formation promoter was used. The results are shown in Table 2 and FIG.

  As is apparent from Table 2 and FIG. 3, when MA65 was used, the rooting rate of round leaf eucalyptus was significantly higher than when no additive was added.

[Example 14]
As a material, genetically modified Arabidopsis (DR5 :: GUS) introduced with Tom Guilfoyl et al. And introduced with an auxin-responsive promoter (DR5) and a reporter gene (β-glucuronidase (GUS) gene) was used (Tom Guilfoyl et al. al., The Plant Cell 9, pp 1963-1971, 1997). DR5 :: GUS is generally used to observe the amount and localization of auxin accumulation using GUS activity as an index. DR5 :: GUS seeds were sterilized by immersing in 1% hypochlorous acid for 5 minutes and washed 5 times with sterilized water. Next, the seeds were sown on 1% agar medium containing 1 μM compound MA65, MS medium diluted 0.5-fold and 1.5% sucrose, and aseptically grown for 1 week in a petri dish. . After immersing the Arabidopsis tissue in a reaction solution (50 mM sodium phosphate, pH 7.0, methanol) containing 1.0 mM 5-bromo-4-chloro-3-indolyl-β-glucuronide (XGluc) , And reacted at 37 ° C. for 24 hours or more. Thereafter, GUS activity was observed with a microscope (manufactured by Keyence Corporation). The results are shown in FIGS. 4-1 and 4-2.

[Comparative Example 7]
GUS activity was observed by culturing in the same manner as in Example 14 except that a medium without addition of compound MA65 was used. The results are shown in FIGS. 4-3 and 4-4.

  In FIGS. 4-1 and 4-2, GUS activity is strongly observed in the whole plant, whereas in FIGS. 4-3 and 4-4, the GUS activity is partial and the activity is weak. Therefore, when MA65 is used, it turns out that the amount of intracellular auxins is increasing.

  From the above, it has been clarified that the adventitious rooting promoter of the present invention exhibits an excellent rooting effect. In addition, it has been clarified that compound MA65 among the adventitious root formation promoters of the present invention is involved in promoting auxin activity by inhibiting auxin metabolism (degradation).

[Examples 15 to 19]
Eucalyptus globulus (hereinafter simply abbreviated as E. globulus) was used as a material for cuttings. That is, from the harvested mother tree, a length of 5 to 20 cm, a node having 1 to 3 nodes, and a leaf having about 2 to 6 leaves were cut out to prepare cuttings.

The bases of the cuttings thus obtained were replaced with KSR51 (Example 15), KSR122 (Example 16), KSR233 (Example 17), KSR221 (Example 18), and KSR236 (Example 19) (Japanese Patent Laid-Open No. 2000). No. 53657, Japanese Patent No. 3762949, Zeitschifffur Naturforschung, 44c, pp. 85-96, 1989) 1 μM each, STS (AgS ₄ O ₆ ) 5 μM as a silver ion source, 4-fold diluted MS medium supplemented with 50 mg / l ascorbic acid as an antioxidant and 2 mg / l IBA as a plant hormone (composition: ammonium nitrate 412.5 mg / l, potassium nitrate 475 mg / l, potassium dihydrogen phosphate 42.52 mg / l l, potassium iodide 0.2 mg / l, carbon source is not added to the medium.) Inserted into a porous support made of foamed phenolic resin (made by Smithers Oasis, trade name: Oasis) wetted with carbon dioxide concentration 1000 ppm At a temperature of 25 ° C. under irradiation with red light having a photosynthesis effective photon flux density of 51.3 μmol / m ² / S, containing a wavelength component of 650 to 670 nm and a wavelength component of 450 to 470 nm at a ratio of 8.2: 1.8. Incubated for 2 months. At this time, as the culture vessel, a cube having a maximum dimension of 10 to 11.5 cm in length, 10 to 11.5 cm in width, and 10.0 cm in height and having a slightly projecting body portion was used. The top surface of the culture vessel is provided with one circular opening to which a polytetrafluoroethylene film (made by Millipore, trade name: Milliceal) having a pore diameter of 0.45 μm is attached. The concentration of carbon dioxide in the culture vessel is the concentration (about 1000 ppm) permeated from the membrane at the opening of the culture container because the carbon dioxide outside the culture vessel permeates through the membrane at the opening of the culture vessel. there were. Irradiation of the red light irradiation to the culture vessel was performed using a product name: CCFL light source unit and a manufacturer name: Nippon Medical Instruments Co., Ltd. as a light irradiation device. Moreover, the humidity in the culture container was adjusted by sealing the culture container with parafilm.

  16 cuttings were inserted per culture container. The rooting rate was calculated from the number of cuttings tested and the number of shoots rooted after culturing for 2 months (number of roots). The results are shown in Table 3-1 and FIG.

[Comparative Example 8]
Culturing was carried out in the same manner as in Example 15 except that a medium not containing an adventitious root formation promoter was used. The results are shown in Table 3-1 and FIG.

[Comparative Examples 9-12]
Instead of the adventitious root formation accelerator of the present invention, brassnazole (Brz) 1.0 μM (Comparative Example 9), pacloputrazole 1.0 μM (Comparative Example 10), pacloputrazole 0.1 μM (Comparative Example 11), Culturing was performed in the same manner as in Example 15 except that a medium supplemented with 5.0 μM pacloputrazole (Comparative Example 12) was used. The results are shown in Table 3-2 and FIG.

  As is clear from Tables 3-1 and 3-2 and FIG. 5, when any compound was added, the rooting rate of eucalyptus was significantly increased as compared with the case where no compound was added. These rooting rates were higher than those of Brz and paclobutrazol which were conventionally known as rooting promoters. In particular, when KSR51, KSR122, KSR221, and KSE236 were used, it exceeded 50%, and all showed a remarkable rooting rate.

[Example 20]
Culturing was performed in the same manner as in Example 18 except that round leaf eucalyptus was used as a material for cuttings. The results are shown in Table 4 and FIG.

[Comparative Example 13]
Culturing was carried out in the same manner as in Example 20 except that a medium not containing an adventitious root formation promoter was used. The results are shown in Table 4 and FIG.

  As is apparent from Table 4 and FIG. 6, when KSR221 was used, the rooting rate of round leaf eucalyptus was significantly higher than when no additive was added.

  From the above, it was revealed that the compound of the present invention exhibits an excellent adventitious root formation promoting effect.

Claims (7)

A plant cell differentiation promoter comprising a compound represented by the general formula (2-2) or a salt thereof, wherein R ²²¹ in the general formula (2-2) is a methyl bromide group, and R ²²² is a fluorine atom. Yes, p is 2, a plant cell differentiation promoter.
(In the general formula (2-2), R ²²¹ is a methyl bromide group , R ²²² is a fluorine atom , and p is 2. ) The plant cell differentiation promoter according to claim 1, which is a plant adventitious root formation promoter. A plant shoot rooting medium containing the plant cell differentiation promoting agent according to claim 1 or 2 . A method for producing a cloned seedling, wherein a plant shoot is cultivated in the presence of the plant cell differentiation promoting agent according to claim 1 or 2 and rooted from the shoot. A method for producing a cloned seedling, wherein a plant shoot is cultivated in the rooting medium according to claim 3 and rooted from the shoot. A method of promoting differentiation of plant cells using a compound represented by the general formula (2-2) or a salt thereof.
(In the general formula (2-2), R ²²¹ is a methyl bromide group , R ²²² is a fluorine atom , and p is 2. ) The method for promoting the differentiation of plant cells according to claim 6 , wherein the differentiation of the cells is promotion of adventitious root formation in plants.