WO2022248683A1

WO2022248683A1 - Plant growth regulator for turfgrass and method for regulating growth of turfgrass

Info

Publication number: WO2022248683A1
Application number: PCT/EP2022/064444
Authority: WO
Inventors: Shin Nakamura; Masaki Sakata
Original assignee: Bayer Intellectual Property Gmbh
Priority date: 2021-05-27
Filing date: 2022-05-27
Publication date: 2022-12-01

Abstract

[Problem] Provided are a plant growth regulator for turfgrasses and a method for regulating the growth of turfgrasses using the same. [Means to Solve the Problem] Provided are a plant growth regulator for turfgrasses, comprising a compound represented by formula (I) or agriculturally acceptable salts thereof, and a method for regulating the growth of turfgrasses using the same.

Description

PLANT GROWTH REGULATOR FOR TURFGRASS AND METHOD FOR REGULATING GROWTH OF TURFGRASS BACKGROUND OF THE INVENTION

Field of the Invention [0001]

The present disclosure relates to a plant growth regulator for turfgrasses and a method for regulating the growth of turfgrasses.

Background Art [0002]

In the field of agriculture, controlling plant growth is an important technology for improving productivity. At present, various kinds of plant growth regulators have been put into practical use for the purpose of regulating plant growth and are contributing to improving the yield of crops and the quality of products. Plant growth regulators include both promoters and inhibitors of the growth of any tissue of a plant, examples thereof including rooting promoters, fruiting promoters, fruit thickening promoters, fruit thinning agents, fruit coloring promoters, dwarfing agents, herbicides, and the like.

[0003] On the other hand, 2-pyridylalkylbenzamide derivatives such as fluopicolide, fluopyram, and fluopimomide have been conventionally known as agricultural and horticultural agents having an excellent activity against phytopathogenic fungi, bacteria or nematodes etc. that damage various plants. For example, Patent Documents 1 and 2 disclose that 2-pyridylalkylbenzamide derivatives such as fluopicolide and fluopyram can be used as a fungicidal agent, patent document 3 discloses fluopimomide, which can be used as a fungicidal or bactericidal agent. Such fungicidal agents containing 2-pyridylalkylbenzamide derivatives are generally applied to dry fields, paddy fields, orchards, golf courses, parks and the like, and can be dispersed directly or diluted with water for application.

[0004]

However, there has not been any report on the 2-pyridylalkylbenzamide derivative as described above as having an effect of growing a plant, particularly an effect of the increase in the number of shoots of turfgrasses.

Prior Art Documents [Patent Literature]

[0005]

Patent Document 1: W099/42447 Patent Document 2: W02004/016088 Patent Document 3: CN102086173

SUMMARY OF THE INVENTION

[0006]

As a result of diligent studies, the present disclosers have now found that 2-pyridylalkylbenzamide derivatives having a specific structure or agriculturally acceptable salts thereof have an excellent growth regulating effect on lawns (and grasses used for lawns). The present disclosure is based on these findings.

[0007]

Accordingly, one object of the present disclosure is to provide a plant growth regulator for turfgrasses and a method of regulating the growth of turfgrasses using the same.

[0008]

In accordance with one embodiment of the present disclosure, there is provided a plant growth regulator for turfgrasses comprising a compound represented by formula (I): wherein

R represents 2,6-dichlorophenyl, or

2,3, 5, 6-tetrafluoro-4-methoxy phenyl, and n represents 1, or agriculturally acceptable salts thereof.

[0009]

According to another embodiment of the present disclosure, there is provided a method for regulating the growth of turfgrasses, comprising applying an effective amount of a compound represented by the above-described formula (I) or agriculturally acceptable salts thereof to the turfgrasses or the section where the turfgrasses are located.

[0010] According to the present disclosure, the compound represented by formula (I) or agriculturally acceptable salts thereof can be used to regulate or promote the growth of turfgrasses. The compounds of the present disclosure or the agriculturally acceptable salts thereof can be used particularly advantageously to promote the number of shoots in turfgrasses. The compounds of the present disclosure or the agriculturally acceptable salts thereof also have a bactericidal effect and can therefore be used particularly advantageously to promote lawn growth while sterilizing the strains that damage the lawns.

[Brief description of the drawings]

[0011]

FIG. 1 is a graph concerning the increase in the number of shoots of turfgrass (creeping bentgrass) comparing the case in which fluopicolide was applied (2400g ai / ha) with the case in which no treatment was applied.

FIG. 2 is a graph concerning the development of new shoots in the stolons of turfgrass (creeping bentgrass) comparing the case in which fluopicolide was applied (960g ai / ha) with the case in which no treatment was applied.

[Specific Description of the Invention]

[0012]

According to one embodiment of the present disclosure, a plant growth regulator comprises a compound represented by formula (I) :

wherein

R represents 2,6-dichlorophenyl or 2,3,5,6-tetrafluoro-4-methoxyphenyl, and n represents 1, or agriculturally acceptable salts thereof.

Surprisingly, the use of the compound represented by formula (I) or the agriculturally acceptable salts thereof allows the rapid growth of turfgrasses.

[0013]

According to a preferred embodiment of the present disclosure, R in the compound represented by formula (I) is preferably 2,6-dichlorophenyl. According to a preferred embodiment of the present disclosure, n in the compound represented by formula (I) is preferably 1.

[0014]

More specifically, the compound represented by formula (I) is preferably fluopicolide (IUPAC name: 2,6-dichloro-N-[[3-chloro-5-(trifluoromethyl)pyridine-2-yl]meth yl]benzamide) represented by the following formula (II):

or fluopimomide (IUPAC name: N-[[3-chloro-5-(trifluoromethyl)pyridin-2-yl]methyl]-2,3,5,6-tet rafluoro-4-methoxybenzamide) represented by the following formula (III):

[0015] The agriculturally acceptable salts of the compound represented by formula (I) are not particularly limited as long as they are acceptable in the present technical field, and examples thereof include ammonium salts such as dimethylammonium salts and triethylammonium salts; inorganic acid salts such as hydrochloride salts, perchlorate salts, sulfate salts and nitrate salts; organic acid salts such as acetate salts and methanesulfonate salts.

[0016]

The content of the agriculturally acceptable salt of the compound represented by formula (I) in the plant growth regulator is, without particular limitation, for example, 0.1 to 100 % by mass, preferably 0.5 to 95 % by mass, more preferably 1 to 50 % by mass, and still more preferably 2 to 35 % by mass. [0017]

The content of the agriculturally acceptable salt of the compound represented by formula (I) in the plant growth regulator is, without particular limitation, for example, 0.1 to 100 % by mass and may preferably contain other components. Thus, according to one embodiment of the present disclosure, the plant growth regulator is provided as a composition.

[0018]

The plant growth regulator may optionally contain an agriculturally acceptable carrier. The agriculturally acceptable carrier is not particularly limited, and may be any of a solid carrier, a liquid carrier, and a gaseous carrier.

[0019]

Examples of the solid carrier include clay, silicate, silica, resin, wax, fertilizer and the like.

[0020]

Examples of the liquid carrier include water, alcohol, ketone, petroleum solvent, saturated or unsaturated hydrocarbon, chlorinated hydrocarbon, liquefied petroleum gas and the like.

[0021]

Examples of the gaseous carrier include LPG, air, nitrogen, carbon dioxide, dimethyl ether and the like.

[0022]

The plant growth regulator may further contain, in addition to the above-described carrier, an agriculturally acceptable additive. Examples of the additive include, without particular limitation, a surfactant, a dispersant, a fixing agent, a defoaming agent, an anti-freezing agent, a dye, a thickening agent, an adhesive, a protective colloid, a penetrating agent, a stabilizer, a metal ion blocking agent, an aggregation preventing agent, an anti-rust agent, a pigment or other auxiliary agent (carboxymethyl cellulose, gum arabic, polyethylene glycol, calcium stearate, and the like).

[0023]

The plant growth regulator may be mixed with or used in combination with another plant growth regulator different from the regulator of the present disclosure, a bactericide, an acaricide, a herbicide, an insecticide, a fertilizer, a BT agent, an entomopathogenic virus agent, and the like. Examples of the drugs which can be mixed or used in combination with include the compounds described in known literatures, "The Pesticide Manual, 17^th Edition, 2015", "Shigemi Shibuya et al., SHIBUYAINDEX -2014- 17^th Edition, February 2014", etc.

[0024]

The dosage form of the plant growth regulator is not particularly limited, and the plant growth regulator may be formulated in any dosage forms such as dusting powders, granules, solutions, concentrated emulsions, emulsifiers, concentrated suspensions, aerosols, and the like.

[0025]

The plant growth regulator can be used for promoting the growth of turfgrasses by using the agriculturally acceptable salts of the compound represented by formula (I) as an active ingredient. Therefore, according to one embodiment of the present disclosure, there is provided a growth promoter for turfgrasses, comprising the agriculturally acceptable salts of the compound represented by formula (I). According to a preferred embodiment, the growth promoter is one which is defined in Article 2 of the Japanese Agricultural Chemicals Regulation Act (promulgated on June 15, 2018).

[0026]

The plant growth regulator can be used to increase the number of shoots in turfgrasses, using as an active ingredient, the agriculturally acceptable salts of the compound represented by formula (I). Thus, according to another preferred embodiment, there is provided an agent for increasing the number of shoots in turfgrasses, comprising the agriculturally acceptable salts of the compound represented by formula (I). [0027]

Also, the agriculturally acceptable salts of the compound represented by formula (I) as above may be applied as they are or in a dosage form as described above to turfgrasses or the section where turfgrasses are located to regulate the growth of turfg rasses. Therefore, according to another embodiment of the present disclosure, there is provided a method for regulating the growth of turfgrasses comprising the step of applying an effective amount of the compound represented by formula (I) or agriculturally acceptable salts thereof to turfgrasses or the location thereof. According to a preferred embodiment, the methods of the present disclosure are methods that promote the growth of turfgrasses. According to a more specific embodiment, the method of the present disclosure is a method for increasing the number of shoots in turfgrasses.

[0028]

Examples of the method for applying the compound represented by the above-described formula (I) or the agriculturally acceptable salt thereof to the turfgrasses or the section where the turfgrasses are located preferably include a dispersing treatment, a soil treatment, a surface treatment, a fumigation treatment, and the like.

[0029]

Examples of the dispersing treatment include dispersing, spraying, misting, atomizing, granulating, and water surface application. Examples of the soil treatment include soil irrigation and soil mixing. Examples of the surface treatment include applying, powder coating, and coating. As the fumigation treatment, for example, the soil is covered with a poly-film after the soil injection. The method of the present disclosure also includes applying the compound represented by formula (I) or the salt thereof, or the plant growth regulator containing these as a penetration and translocation agent.

[0030]

Examples of the section where the turfgrasses are located include places where the turfgrasses grow (soil, in a vinyl house, or in a site). In addition, the portion to which the compound represented by formula (I) or the salt thereof is applied is not particularly limited, and examples thereof include leaves, seeds, roots or plant parts thereof. [0031]

In accordance with the embodiment of the present disclosure, the turfgrasses may be either cool season turfgrasses or warm season turfgrasses. Cool season turfgrasses include bluegrasses (Poa spp.), such as Kentucky bluegrass (Poa pratensis L), rough bluegrass (Poa trivialis L), Canada bluegrass (Poa compressa L.), annual bluegrass (Poa annua L.), upland bluegrass (Poa glaucantha Gaudin), wood bluegrass (Poa nemoralis L.), and bulbous bluegrass (Poa bulbosa L.); the bentgrasses and redtop (Agrostis spp.), such as creeping bentgrass (Agrostis palustris Huds.), colonial bentgrass (Agrostis tenuis Sibth.), velvet bentgrass (Agrostis canina L.), South German Mixed Bentgrass (Agrostis spp. including tenius Sibth., Agrostis canina L., and Agrostis palustris Huds.), and redtop (Agrostis alba L.); the fescues (Festuca spp.), such as red fescue (Festuca rubra L. spp. rubra), creeping fescue (Festuca rubra L.), chewings fescue (Festuca rubra commutata Gaud ), sheep fescue (Festuca ovina L.), hard fescue (Festuca longifolia Thuill), hair fescue (Festuca capillata Lam.), tall fescue (Festuca arundinacea Schreb.), meadow fescue (Festuca elanor L.); the ryegrasses (Lolium spp.), such as annual ryegrass (Lolium multiflorum Lam.), perennial ryegrass (Lolium perenne L.), Italian ryegrass (Lolium multiflorum Lam.); and the wheatgrasses (Agropyron spp.), such as fairway wheatgrass (Agropyron cristatum (L.) Gaertn.), crested wheatgrass (Agropyron desertorum (Fisch.) Schult), and western wheatgrass (Agropyron smithii Rydb.).

[0032]

Other cool season turfgrasses include beachgrass (Ammophila breviligulata Fern.), smooth bromegrass (Bromus inermis Leyss.), cat tails such as Timothy (Phleum pratense L.), sand cat tail (Phleum subulatum L.), orchardgrass (Dactylis glomerata L.), weeping alkaligrass (Puccinellia distans (L.) Pari.) and crested dog's-tail (Cynosurus cristatus L.).

[0033]

Examples of warm season turfgrasses include Japanese turfgrass (Zoysia japonica), Manila grass (Zoysia matrella), Zoysia matrella, Mascarene grass (Zoysia tenuifolia), Zoysia macrostachya, Zoysia hondana, Zoysia sinica, Bermudagrass (Cynodon spp. L. C. Rich), Zoysia grass (Zoysia spp. Willd.), St. Augustine grass (Stenotaphrum secundatum Walt Kuntze), centipedegrass (Eremochloa ophiuroides Munro Hack.), carpetgrass (Axonopus affinis Chase), Bahia grass (Paspalum notatum Flugge.), Kikuyugrass (Pennisetum clandestinum Hochst. ex Chiov.), buffalo grass (Buchloe dactyloids (Nutt.) Engelm.), Blue gramma (Bouteloua gracilis (H.B.K.) Lag. ex Griffiths), seashore paspalum (Paspalum vagin atum Swartz) and sideoats grama (Bouteloua curtipendula (Michx. Torn). [0034]

According to one embodiment of the present disclosure, the turfgrasses are not particularly limited as long as the action of plant growth regulation is exerted by the compound represented by the above-described formula (I) or the agriculturally acceptable salts thereof, and as described above, all turfgrasses including cool season turfgrasses and warm season turfgrasses are encompassed, and preferably, the turfgrasses are healthy. Here, "healthy" means a state in which the turfgrasses are not affected by diseases such as Pythium disease.

[0035]

According to one particular embodiment of the present disclosure, the turfgrasses are preferably cool season turfgrasses, more preferably bentgrasses, and even more preferably creeping bentgrasses.

[0036]

According to another embodiment of the present disclosure, the turfgrasses are at least one selected from Japanese turfgrass, Manila grass, Zoysia matrella, Mascarene grass, Bermuda grass, Bahia grass, St. Augustine grass, centipedegrass, carpetgrass, Kikuyugrass, creeping bentgrass, colonial bentgrass, Kentucky bluegrass, fescues, Italian ryegrass and perennial ryegrass. [0037]

According to the present disclosure, an effective amount of the compound represented by formula (I) or the salts thereof can be preset and applied to turfgrasses upon referring to the growth level of turfgrasses. Therefore, according to a preferred embodiment, the method of the present disclosure comprises the step of determining an effective amount of the compound represented by formula (I) or the salts thereof, using the growth level of turfgrasses as an indicator. The application amount of the compound represented by the above-described formula (I) or the salts thereof may be set as an index with reference to external conditions (e.g., temperature, humidity, etc.) as well as the growth level of turfgrasses.

[0038] The effective amount of the compound represented by formula (I) or the salts thereof can be, without particular limitation, 480 to 4800g ai / ha for example, preferably 720 to 3600g ai / ha, and more preferably 960 to 2400g ai / ha (ai / ha hereinafter means "active substance per 1 hectare" based on 100% of the active compound).

[0039]

According to the present disclosure, the compound represented by formula (I) or the salts thereof can be applied to the turfgrasses by setting the application time in advance by referring to the growth level of the turfgrasses. Therefore, according to a preferred embodiment, the method of the present disclosure comprises the step of determining the application time of the compound represented by formula (I) or the agriculturally acceptable salt thereof using the growth level of turfgrasses as an indicator.

[0040]

Determination of the application time of the compound represented by formula (I) or the salts thereof may include determining the season, time interval and number of applications. For example, the compound represented by formula (I) or the salts thereof may be applied to the turfgrasses over one time during the growth period or the planting period, or over one time at the time before planting, before or after germination.

[0041]

The application time of the compound represented by formula (I) or the salts thereof may be determined upon referring to the season, and seasonal application may be applied. As used herein, "seasonal application" is used to indicate a range of time associated with the season of growth. Since seasons are different in the northern and southern hemispheres, terms indicating the season in terms of temperature such as "spring" and "autumn" require different explanations depending on the geographic location. In addition, tropical climates often experience the seasons described by the terms dry season and rainy season. Accordingly, the term "seasonal application" is used herein to refer to any objective criteria associated with such seasons, regardless of the colloquial terms used.

[0042]

Thus, a season referred to as spring provides the season between winter and summer when most plants begin to grow, usually considered including the months of March to May in the northern hemisphere and September to November in the southern hemisphere. During this season, the average daytime temperatures range from about 30 °F to about 80 °F.

[0043]

Another season, referred to as autumn, represents the transition from summer to winter. In the northern hemisphere, autumn generally begins around September, and in the southern hemisphere, around March. However, there are other definitions of autumn, some of which are based on the month of the year, and others are based on the equinoctial point and on the solstitial point. During this season, the average daytime temperatures range from about 30 °F to about 85 °F.

[0044]

Summer in the southern hemisphere is the entire month of December, January and February and the entire month of June, July and August in the northern hemisphere. This meteorological definition of summer is also consistent with the general sense of summer as the season when there are the longest and hottest days of the year and the daylight is dominant, varying to various degrees. The use of an astronomical beginning of seasons implies that spring and summer have almost the same pattern of day length, with spring increasing from the equinox point to the solstitial point and summer decreasing from the solstitial point to the equinox point, while meteorological summer encompasses the fact that summer builds up toward the longest day and then decreases, and thus has more daytime time than spring. During summer, the average daytime temperatures range from about 55 °F to about 95 °F.

[0045]

Winter begins on the winter solstice and ends on the spring equinox. Calculating from a meteorological point of view, winter is typically the season that begins and ends earlier at the beginning of the months with the equinox point and the solstitial point, having the shortest day and the lowest temperature. Winter is generally of a cold climate, and especially at higher latitudes and altitudes, has snow and ice. The lowest seasonal average temperature is generally experienced in January in the northern hemisphere and in June in the southern hemisphere. During this season, average daytime temperatures range from about 32 °F to about -35 °F.

[0046]

According to another embodiment of the present disclosure, there is also provided the compound represented by formula (I) or the agriculturally acceptable salts thereof as a plant growth regulator for turfgrasses. According to a preferred embodiment, the plant growth regulator is an agent for promoting the growth of turfgrasses. According to another preferred embodiment, the plant growth regulator is an agent for increasing the number of shoots in turfgrasses. According to a preferred embodiment, turfgrasses are bentgrasses. According to a preferred embodiment, the compound represented by the above formula (I) is fluopicolide or fluopimomide.

[0047]

According to another embodiment of the present disclosure, there is also provided the use of the compound represented by formula (I) or the agriculturally acceptable salts thereof as a plant growth regulator for turfgrasses. According to a preferred embodiment, the plant growth regulator is an agent for promoting the growth of turfgrasses. According to another preferred embodiment, the plant growth regulator is an agent for increasing the number of shoots in turfgrasses. According to a preferred embodiment, turfgrasses are bentgrasses. According to a preferred embodiment, the compound represented by the above formula (I) is fluopicolide or fluopimomide.

[0048]

According to another embodiment of the present disclosure, there is also provided the use of the compound represented by the above formula (I) or the agriculturally acceptable salts thereof in the manufacture of a plant growth regulator for turfgrasses. According to a preferred embodiment, the plant growth regulator is an agent for promoting the growth of turfgrasses. According to another preferred embodiment, the plant growth regulator is an agent for increasing the number of shoots in turfgrasses. According to a preferred embodiment, turfgrasses are bentgrasses. According to a preferred embodiment, the compound represented by the above formula (I) is fluopicolide or fluopimomide.

[0049]

According to one embodiment of the present disclosure, the following (1) to (15) can be provided.

(1) A plant growth regulator for turfgrasses, comprising a compound represented by the following formula (I): wherein :

R represents 2,6-dichlorophenyl or

2,3,5,6-tetrafluoro-4-methoxyphenyl , and n represents 1, or agriculturally acceptable salts thereof.

(2) The plant growth regulator according to (1) for promoting the growth of turfgrasses.

(3) The plant growth regulator according to (1) for increasing the number of shoots in turfgrasses.

(4) The plant growth regulator according to (1), wherein the turfgrasses are bentgrasses.

(5) The plant growth regulator according to any one of (1) to (4), wherein R represents 2,6-dichlorophenyl . (6) A method for regulating the growth of turfgrasses, comprising the step of applying an effective amount of a compound represented by the following formula (I) or agriculturally acceptable salts thereof to turfgrasses or the section where the turfgrasses are located.

wherein

R represents 2,6-dichlorophenyl or

2,3,5,6-tetrafluoro-4-methoxyphenyl , and n represents 1. (7) The method according to (6) for promoting the growth of turfgrasses.

(8) The method according to (6) or (7) for increasing the number of shoots in turfgrasses.

(9) The method according to any one of (6) to (8), comprising the step of determining an effective amount of the compound represented by formula (I) or the agriculturally acceptable salts thereof by using the growth level of turfgrasses as an index.

(10) The method according to any one of (6) to (9), further comprising the step of determining the application time of the compound represented by formula (I) or the agriculturally acceptable salts thereof by using the growth level of turfgrasses as an index.

(11) The method according to any one of (6) to (10), wherein the growth level of turfgrasses is the number of shoots in turfgrasses.

(12) The method according to any one of (6) to (11), wherein the turfgrasses are bentgrasses.

(13) The method according to any one of (6) to (12), wherein R represents 2,6-dichlorophenyl.

EXAMPLES

[0050]

The present disclosure will be described in details below; however, the present disclosure shall not be limited to these Examples. Unless otherwise specified, the unit and measurement method shall be in accordance with the provisions of Japanese Industrial Standard (JIS).

[0051]

Test Example 1 : Confirmation of the Effect of Fluopicolide on Growth of Creeping Bentgrasses

PGR (Plant Growth Regulator) effect was tested using a flowable formulation of fluopicolide. Specifically, a plant growth regulator was prepared as shown in Table 1 below, and the effect of fluopicolide on the growth of creeping bentgrasses was evaluated.

[0052] Table 1

[0053]

All treatments were applied using an electric shoulder sprayer equipped with a Hollow-cone nozzle adjusted to deliver 400ml_ / minute. The target crop to be sprayed was a Creeping bentgrass. Fluopicolide was sprayed in an amount of 2400g ai / ha to the fluopicolide-treatment section and the untreated section was sprayed with water only.

[0054]

The plant height of Creeping bentgrasses was adjusted to about 4 to 5 mm and treated with the plant growth regulator described above. The test was run at full randomized block design method with 3 replicates per one treatment. Each creeping bentgrass section was 1 m². All sections were placed using a partitioning method to include treatment with the plant growth regulator.

[0055]

At the time of initial application, a representative sample creeping bentgrass was moist and green, uniform in density and no stress sign was seen due to high temperature. No pests were present in the section and no special maintenance was required. [0056]

During the test period, the creeping bentgrass section was evaluated for a total of four times after 0 day, 8 days, 16 days and 28 days from treatment with the plant growth regulator. Data are given in the number of shoots per 0.81 cm². [0057]

The results are shown in Fig. 1. At 16 days and 28 days from treatment, the number of shoots was significantly increased in the section treated with fluopicolide compared to the untreated section. [0058]

Test Example 2: Effect of Fluopicolide on development of New

Shoots of Creeping Bent Grass Stolons

A plant growth regulator was prepared as shown in Table 2 below and the effect of fluopicolide on the development of new shoots of creeping bentgrass stolons was evaluated.

[0059]

[Table 2]

[0060] All treatments were applied using an Eppendolf micropipette. The target crop was a bentgrass. Fluopicolide was treated in an amount of 5000L per 1 hectare such that the concentration will be 960g ai / ha to the fluopicolide-treatment section. The untreated section was treated with water only. [0061]

Each stolon of bentgrasses was collected before spraying. All the leaves and roots were removed. The stolon was cut so that there were 10 knots and put into plastic packs. After drug treatment, it was cultured at 20-25 °C. Four replicates were performed per one treatment. New shoots were counted after 9 days, 13 days, 19 days, 32 days, and 40 days from treatment (DAT).

[0062]

The results are shown in Fig. 2. At 9 DAT, application of fluopicolide increased the number of new shoots to an average of 3 per one stolon and reached a maximum of 3.5 at 13 DAT. Thus, compared with no treatment, fluopicolide was shown to accelerate the development of new shoots within 2 weeks.

Claims

1. A plant growth regulator for turfgrasses, comprising a compound represented by the following formula (I) :

wherein :

R represents 2,6-dichlorophenyl or

2. The plant growth regulator according to claim 1 for promoting the growth of turfgrasses,

3. The plant growth regulator according to claim 1 for increasing the number of shoots in turfgrasses.

4. The plant growth regulator according to claim 1, wherein the turfgrasses are bentgrasses.

5. The plant growth regulator according to any one of claims 1 to 4, wherein

R represents 2,6-dichlorophenyl . 6. A method for regulating the growth of turfgrasses, comprising the step of applying an effective amount of a compound represented by the following formula (I): wherein

R represents 2,6-dichlorophenyl or

2,3_/5,

6-tetrafluoro-4-methoxyphenyl, and n represents 1, or agriculturally acceptable salts thereof to turfgrasses or a section where the turfgrasses are located.

7. The method according to claim 6 for promoting the growth of turfgrasses.

8. The method according to claim 6 or 7 for increasing the number of shoots in turfgrasses.

9. The method according to any one of claims 6 to 8, comprising the step of determining an effective amount of the compound represented by formula (I) or the agriculturally acceptable salts thereof by using the growth level of turfgrasses as an index.

10. The method according to any one of claims 6 to 9, comprising the step of determining the application time of the compound represented by formula (I) or the agriculturally acceptable salts thereof by using the growth level of turfgrasses as an index.

11. The method according to any one of claims 6 to 10, wherein the growth level of turfgrasses is the number of shoots in turfg rasses.

12. The method according to any one of claims 6 to 11, wherein the turfgrasses are bentgrasses.

13. The method according to any one of claims 6 to 12, wherein

R represents 2,6-dichlorophenyl.