RU2357416C2 - Synergetic herbicide composition as emulsifying concentrate and weed control method - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: description is given to a synergetic herbicide composition in the form of an emulsifying concentrate based on the mixture of 2-ethylhexyl ether 2,4-D (I) and 2-ethylhexyl ether clopyralide (II) containing active reactants with the proportion of (I):(II) equal to from 10:1 to 30:1 as well as to a weed control method. The composition is effective against annual and perennial dicotyledonous weeds in the crops of wheat, barley and maize in the amounts less than those of the known commercial herbicides and herbicide compositions.

EFFECT: composition is highly stable when stored and has better herbicide activity as the known composition.

3 cl, 11 tbl, 13 ex

Description

The invention relates to plant protection products that can be used in crops, and more particularly to a synergistically effective combination of 2,4-dichlorophenoxyacetic acid 2-ethylhexyl ester (2,4D) and 3,6-dichloro-2- 2-ethylhexyl ester pyridinecarboxylic acid (clopiraralide).

In modern agricultural practice, herbicides such as Esteron * KE (* Dow AgroSciences trademark) and Elant KE, the active ingredient, are widely used to control annual and perennial dicotyledonous weeds in crops of wheat, barley, corn and other crops. which is 2,4D 2-ethylhexyl ether (see the Handbook of pesticides and agrochemicals approved for use in the Russian Federation. Agrorus Publishing House, 2006, p. 150 (hereinafter referred to as the “Handbook”, see also The Pesticide Manual , Fourteen Ed., P. 270).

Herbicidal properties of derivatives of 3,6-dichloropicolinic acid (clopyralid), including its esters, are described in US patent No. 3317549. The monoethanolamine salt of clopyralide (Lontrel *) is currently used as a commercial preparation. This drug is more than 2.4 D effective against weeds such as thistles, chamomiles, highlanders, and is recommended for combating them in crops of wheat, barley, oats, millet and corn (see “Reference”, p. 182, The Pesticide Manual, Fourteen Ed., P. 165).

Known combined herbicidal preparation Lontrim *, containing as an active substance a mixture of 2,4D dimethylamine salt (360 g / l, counting on acid) and clopiraralide monoethanolamine salt (35 g / l, counting on acid) in the form of a water-soluble concentrate. The drug is recommended for controlling 2.4D resistant weeds, such as sow thistle and other root shoot weeds in crops of wheat and barley at a dose of 1.5 to 2.0 l / ha, i.e. 593-790 g / ha the amount of active substances (see "Directory", p.149). In Dow AgroSciences brochures, Lontrim * is recommended for controlling the same weeds in corn crops at the same doses of 1.5-2.0 l / ha.

The patent literature describes several synergistically effective combinations of phenoxyacetic acid esters and clopyralide esters. So in the USSR patent No. 587836 a herbicidal composition based on a two-component synergistically effective mixture containing isooctyl ether of 2-methyl-4-chlorophenoxyacetic acid and isooctyl ester of 3,6-dichloropicolinic acid of clopyralide in a ratio of 5: 1 to 50: 1 is described.

The RF patent No. 229351 (prototype) describes a herbicidal composition in the form of an emulsifiable concentrate based on 2,4-dichlorophenoxyacetic acid esters (I) and 3,6-dichloropyridin-2-carboxylic acid (II) in a mass ratio of I: II equal to ( 50-90) :( 10:50) according to the acid equivalent, that is, from 1: 1 to 9: 1.

Among others, the description describes compositions based on a mixture of 2,4-ethylhexyl ester of 2,4D (I) and 2-ethylhexyl ester of 3,6-dichloropicolinic acid (II) in a mass ratio of I: II, from 1: 1.5 to 9: 1 while the mixture in a ratio of 12: 1 is designated as “beyond”, that is, beyond the synergistic effect, and mixtures with I: II ratios of 10: 1 and 11: 1 are not described at all in the description.

As follows from the description, the synergism of the active ingredients was determined under non-standard conditions of the field experiment. These conditions cannot be constant, both during the entire time of the experiment and throughout the space of its conduct, which could not but affect the reliability of the results.

Special experiments to evaluate the combined action of 2,4D (I) 2-ethylhexyl ether and clopiralid (II) 2-ethylhexyl ether, carried out in a greenhouse under constant temperature and humidity, that is, under conditions that exclude any extraneous effect on plants, showed that the synergistic effect in mixtures of these two active active substances is also manifested at an I: II ratio of 10: 1 to 30: 1, as could be expected by analogy with a mixture of 2-methyl-4-chloro-isoctyl ethers phenoxyacetic acid and clopyralide a (USSR patent No. 587836).

The object of the present invention is a synergistically effective herbicidal composition containing, as an active active ingredient, a mixture of 2,4-ethylhexyl ether of 2,4D (I) and 2-ethylhexyl ether of clopyralide (II), in which the mass ratio of components I: II is from 10: 1 to 30: 1 acid equivalent.

The herbicidal composition in accordance with the present invention has, like the composition of the prototype, the form of an emulsifiable concentrate, since this form is most suitable for such active substances as 2,4D esters and clopyralide. The content of 2,4D 2-ethylhexyl ether in the herbicidal composition in the form of an emulsifiable concentrate can vary in the range of 40.6-60.0 wt.% In acid equivalent, and the content of clopiralide 2-ethylhexyl ether can vary in the range of 2.0-4, 5 wt.% Acid equivalent.

The disadvantage of emulsifiable concentrate according to the prototype (RF patent No. 2249351) is a high percentage of nonionic surfactants, such as a mixture of ethoxylated alkyl phenols (OP-7) (20%). These substances are poorly decomposed in the soil and have an adverse effect on the environment (Handbook "Surfactants", Leningrad, "Chemistry", 1975, pp. 285, 305, 306).

The emulsifiable concentrate in accordance with the present invention contains a mixture of nonionic and anionic surfactants in a mass ratio of from 1: 1 to 1: 2

As nonionic surfactants, the composition contains compounds selected from the group consisting of polyethoxylated lauryl alcohol, ethoxylated tridecyl alcohol, ethoxylated castor oil, ethoxylated tall oil, ethoxylated alkyl phenol, and calcium anionic sulfonate or dodecyl as anionic substances. The total amount of surfactants in the composition is in the range of 4-10 wt.%.

Kerosene or xylene are used as organic solvents.

Thus, the synergistic herbicidal composition in accordance with the present invention is an emulsifiable concentrate containing, as active substance, a mixture of 2,4-ethylhexyl ether 2,4D (I) and 2-ethylhexyl ester of clopyralide (II) in a ratio of I: II equal to 10: 1 to 30: 1 in acid equivalent, as a surfactant, contains a mixture of nonionic and anionic surfactants in a ratio of 1: 1 to 1: 2, and as nonionic surfactants substances use substances selected from the group consisting of ethoxylated lauryl alcohol, ethoxylated tridecyl alcohol, ethoxylated castor oil, ethoxylated tallow oil and ethoxylated monoalkylphenol, phenyl sulfonate or dodecylbenzenesulfonyl sulfate are used as the ratio of components, wt.%:

2,4-ethylhexyl ether (acid equivalent) 40.5-60.0 Clopiraralide 2-ethylhexyl ester (acid equivalent) 2.0-4.5 Surfactants 4-10 Solvent The rest is up to 100

The herbicidal composition described above is significantly more stable than the composition of the prototype (for comparison, the preparation most similar in composition was taken as in Example 6, in which the ratio of 2,4D esters and clopiraralide is 9: 1, and their total amount is 45.1%). When diluted with water, a highly dispersed emulsion is obtained, which is evenly distributed on the surface of the plants and is rapidly absorbed into the plant. Therefore, the new herbicidal composition has a higher herbicidal activity against weeds than the composition of the prototype.

Another object of the invention is a method of controlling weeds in crops of crops such as wheat, barley and corn by treating weeds and their habitats with an effective amount of this new composition. The best result is achieved with post-emergence use of drugs at an early stage of plant development.

Field tests conducted in various climatic zones of the Russian Federation showed that the new herbicidal composition suppresses or destroys in the crops of wheat, barley and maize such species of annual and perennial dicotyledonous plants as white gauze, thrown backed up picket, common pomegranate, common pikulnik, zyabra pikliknik , field mustard, rough highlander, highlander highland, buckwheat buckwort, common stork, ragweed, black nightshade, tenure, thistle field, field bindweed, bristles stoy, Tatar lettuce, horse sorrel and others.

Recommended application doses are from 270 to 360 g / ha in the amount of active substances (acid equivalent) (in rare cases, it is necessary to increase the application rate to 400 g / ha). The performance indicators for the drug according to the prototype in the same doses are noticeably lower on average. In all field experiments, a significant increase in crop yield was noted.

Obtaining samples of the herbicidal composition

Example 1

61.5 g of 2,4D 2-ethylhexyl ether, 6.7 g of clopiralide 2-ethylhexyl ether, 3 g of calcium phenyl sulfonate, 2 g of polyethoxylated lauryl alcohol (Empilan * (* Trademark of the company HUNTSMAN)) and 27.3 are placed in the reactor g of kerosene. The components are mixed at 35-40 ° C for 30-40 minutes. The resulting preparation (sample No. 1) has the following composition, wt.%:

2,4-ethylhexyl ether (acid equivalent) 40.6 Clopiraralide 2-ethylhexyl ester (acid equivalent) 4.0 Surfactants 5,0 Kerosene The rest is up to 100

Example 2

66.5 g of 2,4D 2-ethylhexyl ether, 6.7 g of clopiralide 2-ethylhexyl ether, 2 g of ethoxylated castor oil, 3 g of calcium dodecylbenzenesulfonate and 21.8 g of xylene are charged to the reactor. Further, as in example 1. The resulting preparation (sample No. 2) has the following composition, wt.%:

2,4-ethylhexyl ether (acid equivalent) 44.0 Clopiraralide 2-ethylhexyl ester (acid equivalent) 4.0 Surfactants 5,0 Xylene The rest is up to 100

Example 3

72.0 g of 2,4D 2-ethylhexyl ether, 6.5 g of clopiralide 2-ethylhexyl ether, 5 g of calcium phenyl sulfonate, 5 g of polyethoxylated lauryl alcohol and 11.5 g of kerosene are charged into the reactor. Further, as in example 1. The resulting preparation (sample No. 3) has the following composition, wt.%:

2,4-ethylhexyl ether (acid equivalent) 47.5 Clopiraralide 2-ethylhexyl ester (acid equivalent) 3.95 Surfactants 10.0 Kerosene The rest is up to 100

Example 4

77.0 g of 2,4D 2-ethylhexyl ether, 5.7 g of clopiralide 2-ethylhexyl ether, 3.5 g of calcium phenylsulfonate, 3.5 g of ethoxylated tridecyl alcohol and 11.0 g of xylene are charged to the reactor. Further, as in example 1. The resulting preparation (sample No. 4) has the following composition, wt.%:

2,4-ethylhexyl ether (acid equivalent) 51.0 Clopiraralide 2-ethylhexyl ester (acid equivalent) 3.4 Surfactants 7.0 Xylene The rest is up to 100

Example 5

90.0 g of 2,4D 2-ethylhexyl ether, 3.3 g of clopiralide 2-ethylhexyl ether, 3.0 g of calcium phenylsulfonate, 2.0 g of ethoxylated tall oil and 4.7 g of kerosene are charged to the reactor. Further, as in example 1. The resulting preparation (sample No. 5) has the following composition, wt.%:

2,4-ethylhexyl ether acid equivalent) 60.0 Clopiraralide 2-ethylhexyl ester (acid equivalent) 2.0 Surfactants 5,0 Kerosene The rest is up to 100

Example 6

68.0 g of 2,4D 2-ethylhexyl ether, 7.5 g of clopyralide 2-ethylhexyl ether, 2.0 g of ethoxylated monoalkylphenol (Ijepal * (* Trademark of Rhodia)), 4.0 g of calcium dodecylbenzenesulfonate and 4.0 and 19.5 g of kerosene. Further, as in example 1. The resulting preparation (sample No. 6) has the following composition, wt.%:

2,4-ethylhexyl ether (acid equivalent) 45.0 Clopiraralide 2-ethylhexyl ester (acid equivalent) 4,5 Surfactants 6.0 Kerosene The rest is up to 100

Example 7 (prototype)

65.5 g of 2,4D 2-ethylhexyl ether, 7.5 g of clopiralide 2-ethylhexyl ether, 20.0 g of ethoxylated alkyl phenols (OP-7) and 7.0 g of AP 120/200 nephras are charged into the reactor. The resulting preparation (prototype) has the following composition, wt.%:

2,4-ethylhexyl ether (acid equivalent) 40.6 Clopiraralide 2-ethylhexyl ester (acid equivalent) 4,5 Surface-active substance 20,0 Nefras AR 120/200 The rest is up to 100

Physico-chemical and physico-mechanical properties of the obtained preparations, as well as indicators of their stability during storage are presented in table 1.

Biological tests

Example 8. Assessment of the joint action of active active substances.

The experiments to evaluate the joint action in the mixtures were carried out in a greenhouse, in which constant humidity (75%) and temperature (20-23 ° С) were maintained.

Plant seeds were planted in vegetation vessels. Spring wheat was taken as a model of a cultivated plant, and a mixture of dicotyledonous weed plants - grasshopper, white maria, and thyroid was taken as a model of weed plants. Herbicide treatment was carried out in the phase of the beginning of tillering of wheat. The experiments were repeated three times. The effectiveness of herbicides was taken into account 21 days after they were introduced to inhibit the wet mass of weeds in comparison with the control. At the same time, the selectivity of the compounds with respect to wheat was evaluated.

Samples of herbicidal mixtures for evaluating the joint action were prepared by dissolving mixtures of 2,4-ethylhexyl ether 2,4D and 2-ethylhexyl ester of clopyralid in specified ratios in xylene with the addition of a nonionic surfactant (ethoxylated castor oil) identical to all solutions, followed by dilution with water to the desired concentration. Similarly prepared solutions of each of the components of the mixtures.

The synergistic effect was evaluated according to the Colby formula (see S.R. Colby, Weeds, Calculating Synergistic and Antagonistic response of herbicide combinations ", v.15, pp. 20-22, 1967)

E _o = α + β- (α × β): 100,

where α is the% inhibition by component A,

β -% inhibition by component B,

E _o - expected (estimated) efficiency.

The magnitude of the synergistic effect was estimated by the difference between the actual (observed) and expected effectiveness.

The test results are presented in table 2. It follows from the test results that the synergistic effect in mixtures of 2,4-ethylhexyl ether 2,4D and 2-ethylhexyl ester of clopyralide when acting on dicotyledonous plants manifests itself in ratios of these active ingredients from 10: 1 to at least 30: 1.

Therefore, it could be expected that the use of a new herbicidal composition will reduce the application rate of herbicides for controlling weeds in crops of grain crops, which was confirmed in field experiments conducted in various soil and climatic zones of the Russian Federation.

Field test

Example 9

Field tests of herbicides were carried out in the Moscow region on maize crops for silage of the Yubileiny 199 cultivar with a seed rate of 50 kg / ha. Processing was carried out in phase 4 of these leaves of culture once. The experimental plot is littered with the following weeds: white gauze, black nightshade, clinging bedstraw, mountaineer highland, bristly calf, field sow thistle. Accounting for the reduction in the fresh mass of weeds was carried out 30 days after treatment. The negative effect of herbicides on the growth and development of corn plants was not observed. The action of herbicides on individual pitchforks of weeds is presented in table 3. As can be seen from the table, the greatest sensitivity to the preparations under the conditions of the experiment was shown by white gauze and field sow thistle. Standard Elant CE was used in the recommended dose (1.2 l / ha).

Example 10

Field experience in the biological evaluation of herbicidal preparations was laid in the Krasnodar Territory on the crops of maize of the Krasnodar 385MB variety. The size of the plots is 25 m ² , the number of replicates is 4. The preparations were tested at a consumption rate of 0.7; 0.8 and 0.9 l / ha, i.e. 315, 360 and 400 g / ha for the sum of active substances. The standard Elant CE was tested at a rate of 1.2 l / ha, that is, 677 g / ha according to a.m. The experimental plot was littered mainly with dicotyledonous plants. The predominant species were ragweed ragweed, bristly thistle, thrown backworm and Zhmindovy bred. Accounting was carried out before harvesting. With an increase in the consumption rate of the tested preparations, their effectiveness increases, while there was no negative effect on the growth and development of maize under experimental conditions. The effect of herbicidal preparations on certain types of weeds is presented in table 4.

Harvested by hand, followed by collapsing ears and weighing the grain. The results were statistically processed by analysis of variance.

The effect of herbicidal preparations on the corn grain yield is presented in table 5. The yield is almost 2 times higher than the control.

Example 11

Field experience in evaluating the effectiveness of drugs in crops of spring barley cultivars Omsky 90 was carried out in the Omskoye farm from 10.06.05 to 08.20.05. The preparations were introduced into the tillering phase of the culture in two consumption rates of 270 g / ha and 360 g / ha. The standard is the Elant KE herbicide at a dose of 0.8 l / ha, i.e. 450 g / ha. The size of the plots is 25 m ² , the repetition is fourfold. Crops are littered with annual and perennial dicotyledonous weeds, such as bristle thistle, field sow thistle, field bindweed, bicuspid follicle, capybara upturned, stork cycut.

Accounting for the effectiveness of the use of herbicides was carried out before harvesting. The method of harvesting is manual, statistical processing by analysis of variance.

The effect of the preparations on certain types of weeds is presented in table 6, and the effect on the crop is shown in table 7. In the variants with the use of herbicides, a significant increase in yield of 15–20% was obtained.

Example 12

Field experience in evaluating the herbicidal activity of the preparations was laid in the Volgograd region on crops of spring barley Donetsk-8. Perennial dicotyledonous weeds were represented by a bristly thistle, Tatar lettuce, and horse sorrel, annuals - by the cast up pick, white gauze and buckwheat buckwheat. The share of perennials in the community of weed biocenosis reached 40%.

The test results in doses of 270 g / ha indicate their high efficiency in the suppression of these plant species. 30 days after treatment, the decrease in the total number and biomass of weeds on average exceeded 96%. Perennial dicotyledonous weeds after treatment died completely. The action of herbicides affected until the end of the growing season of barley. The barley grain yield in variants using herbicides is 6–9% higher than in the control (table 9). The effect on individual species of weeds is presented in table 8.

Example 13

Field trials of herbicides were carried out in the Tambov region on the sowing of spring wheat cultivar L-503 with a seed rate of 200 kg / ha. The size of the plots is 50 m ² , the repetition is fourfold. Processing was carried out in the tillering phase once. The experimental plot is littered with the following weeds: white gauze, thrown backwood, common pikulnik, common chickpear, field mustard, rough mountaineer, buckwheat buckwheat, field sow thistle, field bindweed, bristose calf. The effect of herbicides on certain types of weeds in comparison with the prototype and control are presented in table 10.

The effect of herbicides on spring wheat yield is presented in table 11.

Claims (3)

1. A synergistic herbicidal composition in the form of an emulsifiable concentrate containing a mixture of two active active ingredients - 2-ethylhexyl ester of 2,4-dichlorophenoxyacetic acid (2,4D) and 3,6-dichloro-2-pyridinecarboxylic acid 2-ethylhexyl ester (clopyralid), a surfactant (surfactant) and a solvent, characterized in that 2,4D (I) 2-ethylhexyl ether and clopyralide (II) 2-ethylhexyl ether are in a mixture in a ratio of I: II from 10: 1 to 30: 1, as a surfactant, the composition contains a mixture of nonionic and ani active surfactants in a ratio of 1: 1 to 1: 2, and as a nonionic surfactant, it contains substances selected from the group including ethoxylated lauryl alcohol, ethoxylated tridecyl alcohol, ethoxylated castor oil, ethoxylated tallow oil, ethoxylated monoalkylphenol, as anionic surfactants - calcium phenyl sulfonate or calcium dodecylbenzenesulfonate, as solvents - kerosene or xylene in the following ratio of components, wt.%:
2,4-ethylhexyl ether (acid equivalent) 40.5-60.0 Clopiraralide 2-ethylhexyl ester (acid equivalent) 2.0-4.5 Surfactants 4-10 Solvent The rest is up to 100 2. A method of controlling weeds in crops of crops by treating them with a herbicidal composition based on a mixture of 2,4D 2-ethylhexyl ester of clopiralide 2-ethylhexyl ester, characterized in that an effective amount of the herbicidal composition is applied to the plants to be destroyed and their habitats according to claim 1. 3. The method of controlling weeds in crops of crops according to claim 2, characterized in that the crops are wheat, barley and corn.