GB2274102A

GB2274102A - Plant growth inhibitors

Info

Publication number: GB2274102A
Application number: GB9400406A
Authority: GB
Inventors: Renate Vosswinkel; Graham Holmwood
Original assignee: Bayer AG
Current assignee: Bayer AG
Priority date: 1993-01-11
Filing date: 1994-01-11
Publication date: 1994-07-13
Anticipated expiration: 2014-01-11
Also published as: GB9400406D0; GB2274102B; DE4300452A1; FR2700243A1; FR2700243B1

Description

2274102 Plant growth inhibitors The present invention relates to new

active compound combinations composed of known hydroxyethyl-triazolyl derivatives on the one hand and of 2-chloroethyl trimethyl -ammonium chloride, which is known, on the other hand and which are highly suitable for inhibiting the growth of plants.

It has already been disclosed that 1-(4-chlorophenoxy) 2-(1,2,4-triazol-l-yl-methyl)-3,3-dimethyl-butan-2-ol and 1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazol-l-yl- methyl)-pentan-3-ol have plant-growth-regulating pro perties and can also be used for inhibiting the growth of plants (cf. European Offenlegungsschrift 0,040,345 and European Offenlegungsschrift 0,224,077). The activity of these substances is good, but leaves something to be desired in some cases when used at low application rates.

Furthermore, it has been disclosed that 2-chloroethyl trimethyl- ammonium chloride can be used for regulating the growth of plants (cf. US Patent Specification

3,156,554). However, the activity of this substance is not always satisfactory when used at low application rates.

It has now been found that the new active compound combinations of A) a hydroxyethyl-triazolyl derivative of the formula OH -X-CH2-C-C(CHA (I) U112 N N- in which X represents an oxygen atom or a CH2 group.

and B) 2-chloroethyl-trimethyl-ammonium chloride, of the 5 f ormula CH3 Cl-CH2-CH2- [3 Cl CH3 are highly suitable f or inhibiting the growth of plants.

Furthermore. it has been found that excellent plant growth in.hibition can also be achieved when seed or plants are treated with a hydroxyethyl-triazolyl deriva- tive of the f ormula (I) before emergence and with the compound of the formula (II) after emergence.

Surprisingly, the growth-inhibiting activity of the active compound combinations according to the invention by far exceeds the total of the activities of the indi vidual active compounds. Moreover, an unexpected super additive growth inhibition is also found when the plants are treated in succession with the individual active compounds. This shows that a synergistic effect which could not have been predicted exists in each case, not only a supplementation of action.

Hydroxyethyl-triazolyl derivatives of the formula (I) are 1-(4-chlorophenoxy)-2-(1,2,4-triazol-l-yl-methyl)3f3-dimethylbutan-2-ol, of the formula OH 1 O-CH2-L;-(;(U"3 (P1) 1 CH2 N --N is N-JI and 1-(4-chlorophenyl)-4,4-dimethyl-3-(1,2,4-triazoll-yl-mmethyl)-pentan-3-ol of the formula OH ci---- /\-CH2-Cti2-u-u(CH3 (P2) uk'2 N Each of the compounds of the formula (I-1) and (1-2) have an asymmetrically substituted carbon atom and can there f ore exist in the f orm of racemates or in the f orms of the two optical isomers. The present invention relates to active compound combinations on the basis of isomer mixtures and on the basis of the individual isomers.

The active compounds in the active compound combinations according to the invention have already been disclosed (cf. European Offenlegungsschrift 0,040,345 and US Patent Specification 3,156.554).

The synergistic effect is particularly pronounced when the active compounds are present in the active compound combinations according to the invention in certain ratios is by weight. However, the ratios by weight of the active compounds in the active compound combinations can be varied within a relatively wide range. In general. 0.05 to 20 parts by weight, preferably 0.1 to 10 parts by weight, of active compound of the formula (II) is generally used per part by weight of active compound of the formula (I).

If the active compounds of the formula (I) and (II) are applied in succession, the synergistic ef f ect is also particularly pronounced when the active compounds are used in certain ratios by weight. Again, the ratios by weight can be varied within a substantial range. In gen eral, 0.05 to 200 parts by weight, preferably 0.1 to parts by weight, of active compound of the formula (11) are used per part by weight of active compound of the formula (I).

As plant growth regulators, the active compound combina tions according to the invention interfere in the meta bolism of the plants and can therefore be used for inhi biting the growth, preferably for inhibiting the growth is in length of useful plants. The danger of bending Clodging") of the crop plants before harvesting is the reby reduced or completely eliminated. Furthermore, the active compound combinations according to the invention can strengthen the stem of crop plantsf such as cereals and oilseed rape, which again counteracts lodging. Use of the active compound combinations according to the in vention for shortening and strengthening the stem enables higher amounts of fertilizer to be applied to increase the yield, without danger of the crop plants lodging.

Inhibition. of the vegetative growth of plants can also lead to increases in yield, since the nutrients and assimilates benefit the fruit to a greater extent than they benefit the vegetative part:s of plants.

By crop plants there are to be understood, in the present case, dicotyledon and monocotyledon crop plants. The active compound combinations according to the invention can preferably be used for inhibiting growth in wheat, barley, rye, oats, cotton and oilseed rape.

The active compound combinations according to the inven tion can be converted into the customary formulations, such as solutions, emulsions, suspensions, powders, foams, pastes, granules, aerosols, very fine capsules in polymeric substances and in coating compositions for seed, as well as ULV cold and warm mist formulations.

These formulations are produced in a known manner, for example by mixing the active compounds with extenders, is that is, liquid solvents, liquefied gases under pressure, andlor solid carriers, optionally with the use of sur f ace-active agents, that is, emulsifying agents and/or dispersing agents and/or foam-f orming agents. In the case of the use of water as an extender, organic solvents'can, for example, also be used as auxiliary solvents. As liquid solvents, there are suitable in the main: aroma tics, such as xylene, toluene or alkylnaphthalenes, chlorinated aromatics or chlorinated aliphatic hydro carbons, such as chlorobenzenes, chloroethylenes or methylene: chloride, aliphatic hydrocarbons. such as cyclohexane or paraffins, for example mineral oil frac tions, alcohols, such as butanol or glycol as well as their ethers and esters, ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, strongly polar solvents, such as dimethylformamide and dimethyl sulphoxide, as well as water. By liquefied gaseous extenders or carriers are meant liquids which are gaseous at ambient temperature and under atmospheric pressure, for example aerosol propellants, such as halo genated hydrocarbons as well as butane. propane, nitrogen and carbon dioxide. As solid carriers there are suitable:

for example, ground natural minerals, such as kaolinst clays, talc. chalk. quartz. attapulgite, montmorillonite or diatomaceous earth, and ground synthetic minerals, such as highly disperse silica, alumina and silicates; as solid carriers for granules there are suitable: for example, crushed and fractionated natural rocks such as calcite. marble. pumice, seplolite and dolomite, as well as synthetic granules of inorganic and organic meals, and granules of organic material such as sawdust,, coconut shells, maize cobs and tobacco stalks; as emulsifying and/or foam-forming agents there are suitable: for example, non-ionic and anionic emulsifiers, such as polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, for example alkylaryl polyglycol ethers, alkylsulphonates, alkyl sulphates, arylsulphonates as well as albumen hydrolysis products; as dispersing agents there are suitable: for example lignin-sulphite waste liquors and methylcellulose.

Adhesives such as carboxymethylcellulose and natural and synthetic polymers in the form of powders, granules or latices, such as gum arabic, polyvinyl alcohol and poly vinyl acetate, as well as natural phospholipids, such as cephalins and lecithins, and synthetic phospholipids, can be used in the formulations. Further additives can be mineral and vegetable oils.

It is possible to use colorants such as inorganic pig ments, for example iron oxide, titanium oxide and Prussian Blue, and organic dyestuffs, such as alizarin dyestuf f s, azo, dyestuf f s and metal phthalocyanine dye stuffs, and trace nutrients such as salts of iron, manganeseF boron, copper, cobalt, molybdenum and zinc.

The formulations in general contain between 0.1 and per cent by weight of active compound, preferably between 0.5 and 90%.

The active compound combinations according to the inven tion or the individual active compounds can be used as such or, in their formulations, as a mixture with known active compounds, such as fungicides, insecticides, acaricides and herbicides, and also as mixtures with fertilizers.

The active compound combinations according to the inven tion or the individual active compounds can be used as such, in the f orm of their f ormulations or as the use f orms prepared theref rom by further dilution, such as ready-to-use solutions, emulsifiable concentrates.

emulsions, powders, pastes and granules. They are used 1 1 in the customary manner, for example by watering, spraying, atomizing, scattering, dusting or pre-plant incorporation.

The amounts of active compound applied can be varied within a substantial range. In general, the application rates are between 0.001 and 50 kg, preferably between 0.01 and 10 kg, of the active compound combination or individual active compounds per hectare of soil surface.

As regards the time of application, the active compound combinations according to the invention or the appli cation of the individual active compounds in succession will be carried out within a preferred period of time whose exact limits depend on the climatic and vegetative conditions.

When application of the active compounds is staggered, a procedure is generally followed in which seed or plants are treated with active compound of the formula (I) before.emergence and with active compound of the formula (II) after emergence. Post-emergence treatment is prefer ably effected in the 2- or 3-leaf stage of the plants.

The good growthinhibiting action of the active compound combinations according to the invention or of the active compounds of the formulae (I) and (I1) which are used in succession can be seen from the examples which follow.

While the individual active compounds, when used on their own, show weaknesses with regard to their growth-inhibiting action, the combinations, or the individual active compounds used in succession, display an activity which exceeds the simple additive effect.

Growth regulators display a synergistic ef f ect in all those cases where the growth-regulating activity of the active compound combinations exceeds the total of the effects of the individually applied active compounds.

The activity which can be expected for a given combina tion of two plant growth regulators can be calculated as follows (cf. S.R. Colby, "Calculating synergistic and antagonistic responses of herbicide combinations". Weed 1_5, 20-22 [1967j):

if X = % growth regulation by active compound (A) at an application rate of n kg/ha and Y = % growth regulation by active compound (B) at an application rate of m kg/ha and E = the growth regulation to be expected by active compounds (A) and (B) at an application rate of n and m kg/ha.

then E = X + Y - X X Y If the actual growth inhibition exceeds the calculated value, then the activity of the combination is superadditive, i.e. there is a synergistic effect.

The tables of the examples which follow demonstrate clearly that the found growth-inhibiting activity of the active compound combinations according to the invention exceeds the calculated activity, i.e. there is a synergistic effect.

Example 1:

Inhibition of growth in wheat Solvent: 30 parts by weight of dimethylformamide Emulsifier: 1 part by weight of polyoxyethylene sorbitan monolaurate To produce a suitable preparation of active compounds of the formula (I), one part by weight of active compound is mixed with the stated amounts of solvent and emulsifier and the concentrate is diluted to the desired concentra tion with water.

To produce a suitable preparation of the active compound of the formula (II), a commercially available liquid formulation containing 72 per cent by weight of this active compound is diluted to the desired concentration with water.

To produce a suitable preparation of an active compound combination according to the invention. 1 part of active compound of the formula (I) is mixed with the stated amounts of solvent and emulsifier, the desired amount of commercially available liquid formulation containing 72 per cent by weight of the active compound of the formula (II) is added, and the mixture is made up to the desired concentration with water.

Wheat plants are grown in a greenhouse in pots having a surf ace area of in each case 100 cm until they have reached the 2-leaf stage. In this stage, the plants are sprayed with 500 1/ha (converted) of the active compound preparation. After three weeks, the height of all plants is measured. and the inhibition of growth in per cent of the height of the control plants is calculated.

The figures denote:

0% = no action (like untreated control) 100% = total inhibition of growth (standstill of growth) The active compounds, application rates and test results can be seen from the table which follows:

Table 1:

Inhibition of growth in wheat Active compound or Application rate of Inhibition of active compound active compound in growth in % combination g/ha found calculated 0 (untreated control) Known:

(1-1) 50 2 (1-2) 75 0 (11) 125 0 is According to the invention:

U-1) 50 + + 19 2 (11) 125_) (1-2) 75 + + 19 0 Inhibition of growth calculated using Colby's formula above.

Example 2:

Inhibition of growth in barley Solvent: 30 parts by weight of dimethylformamide Emulsifier: 1 part by weight of polyoxyethylene sorbitan monolaurate To produce a suitable preparation of active compound of the formula (I), one part by weight of active compound is mixed with the stated amounts of solvent and emulsifier and the concentrate is diluted to the desired concentration with water.

To produce a suitable preparation of an active compound combination according to the invention, 1 part of active compound of the formula (I) is mixed with the stated amounts of solvent and emulsifier, the desired amount of commercially available liquid formulation containing 72 per cent by weight of the active compound of the formula (II) is added, and the mixture is made up to the desired concentration with water.

Barley plants are grown in a greenhouse in pots having a surface area of in each case 100 cm- until they have reached the 2-leaf stage. In this stage, the plants are sprayed with 500 1/ha (converted) of the active compound preparation. After three weeks, the height of all plants is measured, and the inhibition of growth in per cent of the height of the control plants is calculated.

The figures denote:

- is - Table 2:

Inhibition of growth in barley Active compound or Application rate of Inhibition of active compound active compound in growth in % combination g/ha found calculated') 0 (untreated control) Known:

(1-1) 50 0 (11) 100 0 According to the invention:

(1-1) 50 + + 22 0 (II) j 100 Inhibition of growth calculated using Colby's formula above.

Example 3:

Inhibition of growth in rye Solvent: 30 parts by weight of dimethylformamide Emulsifier: 1 part by weight of polyoxyethylene sorbitan monolaurate To produce a suitable preparation of active compound of the formula (I), one part by weight of active compound is mixed with the stated amounts of solvent and emulsifier and the concentrate is diluted to the desired concentration with water.

To produce a suitable preparation of an active compound combination according to the invention, 1 part of active compound of the formula (I) is mixed with the stated amounts of solvent and emulsifier, the desired amount of commercially available liquid formulation containing 72 per cent by weight of the active compound of the is formula (II) is added, and the mixture is made up to the desired concentration with water.

Rye plants are grown in a greenhouse in pots having a surface area of in each case 100 cm until they have reached the 2-leaf stage. In this stage, the plants are sprayed with 500 1/ha (converted) of the active compound preparation. After three weeks, the height of all plants is measured, and the inhibition of growth in per cent of the height of the control plants is calculated.

The figures denote:

- 18 Table 3:

Inhibition of growth in rye Active compound or Application rate of Inhibition of active compound active compound in growth in combination g/ha found calculated" 0 (untreated control) Known:

0 - 3 - 0 - 0 - According to the invention:

(I-1) + 19 0 (11) 100 j (1-1) 100 + + 19 3 (ii)-J -11i Inhibition of growth calculated using Colby's formula above.

Example 4:

Inhibition of growth in cotton Solvent: 30 parts by weight of dimethylformamide Emulsifier: 1 part by weight of polyoxyethylene sorbitan monolaurate To produce a suitable preparation of active compound of the formula (I). one part by weight of active compound is mixed with the stated amounts of solvent and emulsifier and the concentrate is diluted to the desired concentration with water. To produce a suitable preparation of the active compound of the f ormula (II), a commercially available liquid formulation containing 72 per cent by weight of this active compound is diluted to the desired concentration with water. To produce a suitable preparation of an active compound combination according to the invention, 1 part of active compound of the f ormula (I) is mixed with the stated amounts of solvent and emulsifier, the desired amount of 20 commercially available liquid formulation containing 72 per cent by weight of the active compound of the formula (II) is added, and the mixture is made up to the desired concentration with water. Cotton plants are grown in a greenhouse in pots having a - 20 surface area of in each case 100 cm until they have reached the 2-leaf stage. In this stage, the plants are sprayed with 500 1/ha (converted) of the active compound preparation. After three weeks, the height of all plants is measured, and the inhibition of growth in per cent of the height of the control plants is calculated.

The figures denote:

21 - Table 4:

Inhibition of growth in cotton Active compound or Application rate of Inhibition of growth active compound active compound in in % 5combination g/ha found calculated') 0 (untreated control) Known:

0 (11) 25 0 According to the invention:

U-1) so + + 17 0 (I I) 25j Inhibition of growth calculated using Colby's formula above.

Example 5:

Inhibition of growth in wheat Solvent: 30 parts by weight of dimethylformamide Emulsifier: 1 part by weight of polyoxyethylene sorbitan monolaurate To produce a suitablepreparation of active compound of the formula (I), one part by weight of active compound is mixed with the stated amounts of solvent and emulsifier and the concentrate is diluted to the desired concentration with water.

To produce a suitable preparation of the active compound of the formula (K), a commercially available liquid formulation containing 72 per cent by weight of this active compound is diluted to the desired concentration with water.

In a greenhouse, wheat kernels are planted in pots having a surface area of in each case 100 cml. 24 hours after planting, active compound of the formula (I) is sprayed onto the soil at a rate of 500 1/ha (converted) active compound preparation. The plants are then grown until they have reached the 2-leaf stage and then sprayed with 500 1/ha (converted) of active compound preparation of the active compound of the formula (II).

After three weeks, the height of all plants is measured, and the inhibition of growth in per cent of the height of the control plants is calculated.

The figures denote:

Table 5:

Inhibition of growth in wheat (pre- and post-emergence treatment) Active compound AD plication rate of Inhibition of growth active compound in in % g/ha found calculated" 0 (untreated control) Known:

0 2 is 100 4 According to the invention:

+ + 20 4 (II)) 100j (I - 1) ++) 5 + + 18 6 (11) 100 Inhibition of growth calculated using Colby's formula above Pre-emergence application Post-emergence application Example 6:

Inhibition of growth in cotton (pre- and post-emergence treatment) Solvent: 30 parts by weight of dimethylformamide Emulsifier: 1 part by weight of polyoxyethylene sorbitan monolaurate To produce a suitable preparation of active compound of the formula (I), one part by weight of active compound is mixed with the stated amounts of solvent and emulsifier and the concentrate is diluted to the desired concentration with water.

In a greenhouse, cotton seeds are planted in pots having a surface area of in each case 100 em. 24 hours after planting, active compound of the formula (I) is sprayed onto the soil at a rate of 500 1/ha (converted) active compound preparation. The plants are then grown until they have reached the 2-leaf stage and then sprayed with 500 1/ha.(converted) of active compound preparation of the active compound of the formula (II). After three weeks, the height of all plants is measured, and the inhibition of growth in per cent of the height of the control plants is calculated.

The figures denote:

1 Table 6:

Inhibition of growth in cotton (pre- and post-emergence treatment) Active compound Application rate of Inhibition of growth active compound in in % g/ha found calculated 0 (untreated control) Known:

(1 25 2 2 According to the invention:

+ + 25 4 1) 25 Inhibition of growth calculated using Colby's formula above Pre-emergence application Post-emergence application Example 7:

Inhibition of growth in oilseed rape Solvent: 30 parts by weight of dimethylformamide Emulsifier: 1 part by weight of polyoxyethylene sorbitan monolaurate To produce a suitable preparation of active compound of the formula (I), one part by weight of active compound is mixed with the stated amounts of solvent and emulsifier and the mixture is made up to the desired concentration with water.

To produce a suitable preparation of the active compound of the f ormula (II),, a commercially available liquid formulation containing 72 per cent by weight of this active compound is made up to the desired concentration with water.

To produce a suitable preparation of an active compound combination according to the invention, 1 part by weight of active compound of the formula (I) is mixed with the stated amounts of solvent and emulsifier, the desired amount of commercially available liquid formulation containing 72 per cent by weight of the active compound of the formula (II) is added, and the mixture is made up to the desired concentration with water.

Oilseed rape plants are grown in a greenhouse in pots having a surface area of in each case 100 c& until they have reached the 3- to 4-leaf stage. In this stage. the plants are sprayed with 500 1/ha (converted) of the active compound preparation. After seven weeks, the height of all plants is measured. and the inhibition of growth in.per cent of the height of the control plants is calculated.

- 28 The figures denote:

Table 7:

Inhibition of growth in oilseed rape Active compound or Application rate of Inhibition of growth active compound active compound in in % combination g/ha found calculated' 0 (untreated control) Known:

(1-1) 75 3 (1-2) 75 0 (11) 250 0 According to the invention:

(1-1) 75 + + 61 3 (11) 250 (1-2) 75 + + 33 0 (11) 250 Inhibition of growth calculated using Colby's formula above.

- 30 E.... amp 1 e 8:

Inhibition of growth in wheat (seed treatment and post emergence treatment) Solvent: 30 parts by weight of dimethylformamide Emulsifier: 1 part by weight of polyoxyethylene sorbitan monolaurate To produce a suitable preparation of active compound of the formula (I), one part by weight of active compound is mixed with the stated amounts of solvent and emulsifier and the concentrate is diluted to the desired concentration with water.

To produce a suitable preparation of the active compound of the formula (II), a commercially available liquid formulation containing 72 per cent by weight of this is active compound is diluted to the desired concentration with water.

Wheat kernels are treated with the preparation of active compound of the formula (I) and then, in the greenhouse, planted in pots having a surface area of in each case 100 cm. The plants are grown until they have reached the 2-leaf stage and then sprayed with 500 1/ha (converted) of preparation of the active compound of the formula (II). Six.weeks after the seed treatment, the height of all plants is measured and the inhibition of growth in per cent of the height of the control plants is calculated.

- 31 9 The figures denote:

Table 8:

Inhibition of growth in wheat (seed-treatment and postemergence treatment) Active compound Application rate of Inhibition of growth active compound in in % g/100 kg of seed found calculated 0 (untreated control) Known:

2.5 5 0 According to the invention:

(I-1) __1 2.5 + + 17 5 (I 1) 200 Inhibition of growth calculated using Colby's formula above Application by seed treatment Post-emergence application It will of course by understood that the present o invention has been described above purely by way of example., and that modifications of detail can be made within the scope of this invention.

Claims

Patent Claims

1. Compositions for inhibiting plant growth, characterized in that they contain an active compound combination consisting of A) a hydroxyethyl-triazolyl derivative of the formula OH 1 cl X-CH2 -C-L(Lki3)3 (I) CH2 1 N N N-J1 in which X represents an oxygen atom or a CH2 group.

and B) 2-chloroethyl-trimethyl-anmonium chloride, of the formula CH3 Cl-CH2-CH2-N-CH3 cl 1 CH3 34 -

2. Composition according to Claim 1, characterized in that, in the active compound combinations, the ratio by weight of active compound of the formula (I) to active compound of the formula (II) is 5 between 1:0.05 and 1:200.

3. Method of inhibiting the growth of plants, characterized in that active compound combinations according to Claim 1 are allowed to act on the plants and/or their environment.

4. Use of active compound combinations according to Claim 1 for inhibiting the growth of plants.

5. Process for the preparation of plant growth inhibi tors, characterized in that active compound combinations according to Claim 1 are mixed with extenders and/or surface-active agents.

6. Method of inhibiting the growth of plants, charac terized in that seed or plants are treated with a hydroxyethyl-triazolyl derivative of the formula (I) according to Claim 1 before emergence and with the compound of the formula (II) according to Claim 1 after emergence.

7. Method according to Claim 6 characterized in that 0.05.-to 200 parts by weight of active compound of the fo = la (II) are employed per part by weight of active compound of the formula (I).

8. Composition according to claim 1 as hereinbefore specifically indentified in any one of the Examples

9. Method according to claim 3 or 6, substantially as described in any one of the Examples.