EA032341B1 - Stable suspension concentrate, use thereof and method for control of undesired vegetation - Google Patents

Abstract

The invention is related to the field of agriculture and can be used for protection of sown beet against weed infestation. The invention discloses a stable suspension concentrate having a herbicidal effect based on a mixture of metamitron with lenacil, particles of which are dispersed in a polar diluent and have a mean size of not more than 5 μm. Total content of said active ingredients is in the range of 300 to 750 g/l. The invention provides improved biological protection of sown beet in respect of a broadened range of monocotyledon and dicotyledon weed plants including rape fallen seed, extends shelf life of preparations based on the suspension concentrate under various weather conditions.

Description

The invention relates to the field of agriculture and can be used to protect against contamination of beet crops. Stable suspension suspension with a herbicidal action based on a mixture of metamitron with lenacil, particles of which are dispersed in a polar diluent and have an average size of not more than 5 microns, is claimed. The total content of these active substances in the concentrate is in the range from 300 to 750 g / l. The invention provides improved biological protection of beet crops in relation to an expanded spectrum of monocotyledonous and dicotyledonous weeds, including rape seedlings, increases the shelf life of preparations based on it under various weather conditions.

032341 Β1

032341 B1

The present invention relates to the field of agriculture and can be used to protect against clogging of crops of cultivated plants.

Controlling weediness of crops is one of the most important and complex elements in the technology of their cultivation. The difficulty in selecting the best means of protection is that it is necessary to take into account the species and quantitative composition of weeds, which depends on climatic conditions, the soil cultivation system, predecessors in crop rotation and other factors. Weeds negatively affect germination, growth and development, crop productivity, as well as the quantity and quality of the crop. This is especially true for sugar beet crops, the crop that is most demanding on field cleanliness, especially during the initial growing season.

In recent years, the problem of combating rape scavenger in beet crops has arisen. Due to the saturation of crop rotation with rapeseed, its scavenger is the main weed of beet fields. Difficulties in controlling this weed are primarily due to the unevenness of its seedlings in terms of time - the weed can appear within two or more months (from early April to June). A rapeseed drop, starting from the phase of 3 pairs of leaves, exhibits phase resistance to most herbicides recommended for use and its destruction requires increased drug rates or a combination of three or more herbicides, which can cause severe beet stress. In addition, the presence of canola carrion in beets makes it difficult to harvest, leading to contamination of root crops. All this requires a more careful selection of the protection system with the aim of sparing impact on beet seedlings and, as a result, obtaining high yields of this crop.

Currently, for the treatment of beet crops, many chemical protective agents (both single-component and combined) have been developed and recommended for use, however, they have certain drawbacks, so there is still a need to improve them.

The best known means of weed control are betanals - preparations based on phenmedifam and desmedifam (for example, I8 5246912 A, class Α01Ν 43/707, publ. 21.09.1993). Sometimes betanals contain etofumezate as the third active component. These drugs have temperature limits for their use. It is impossible to carry out processing on hot days when the air temperature exceeds 25 ° C. Failure to comply with this requirement leads to serious negative consequences: leaf burns, depression and even death of beet seedlings are possible. When processing on days with air temperatures below 16 ° C, their effectiveness decreases. Low temperatures reduce the intensity of metabolic processes in plants and lead to a drop in the level of effectiveness of the drugs. The effectiveness of betanals on rapeseed carrion is low. In addition, the treatment in the phase of the cotyledons, two sheets of weeds with small doses of the drug does not completely destroy other broadleaf weeds.

In practice, beet crops littered with dicotyledonous weeds with a predominance of rapeseed fall are treated with the Russian drug TRICEPS, VDG (trademark CJSC Firma August) (see List of pesticides and agrochemicals approved for use on the territory of the Russian Federation, Appendix to the journal Plant Protection and Quarantine, Moscow , 2016, No. 4, p. 535). As the main active ingredient, this drug contains triflusulfuron-methyl. This formulation has good operational characteristics, but is not effective with respect to subsequent waves of weeds: weeds that appeared after treatment do not die, because the action of the substance through the root system is limited.

Metamitron-based preparations are widely used to combat the contamination of sugar beet crops, for example, PILOT, VSK (trademark of Augusta Firm CJSC) (see List of pesticides and agrochemicals approved for use in the Russian Federation, Appendix to the journal Plant Protection and Quarantine, Moscow, 2016, No. 4, p. 458). This drug controls annual dicotyledonous weeds, and is ineffective against perennial dicotyledonous and cereal weeds.

Unicomponent preparations based on Lenacil are also known from the prior art, for example, LENACIL, SP (trademark KEMINOVA / C) (see the List of pesticides and agrochemicals approved for use in the Russian Federation, Appendix to the journal Protection and Plant Quarantine, Moscow, 2016 ., No. 4, p. 457). This drug is a soil herbicide: it is used once strictly until the first seedlings of the crop. The use of this drug is associated with the following restrictions: it is dangerous when handling, because it is dusty; the large particle size of the active substance in the preparation leads to clogging of the nozzles of the atomizer, cakes during storage. The average particle size in a wettable powder (SP) is on average 30-40 microns.

To enhance biological effectiveness, as well as expand the temperature range for use, combinations of betanals with drugs based on metamitron and / or lenacil are used. However, tank mixtures have a number of disadvantages associated primarily with physical and chemical compatibility. Sometimes the incompatibility of the drugs is immediately visible: the liquid obtained by mixing them begins to exfoliate, a precipitate forms, flakes or other similar signs of unsuitability of the mixture form. During the spraying of the working solution, the nozzles of the sprayer become clogged. Also, in the process of preparing tank mixtures, the hardness and temperature of the water used must be taken into account. But most often the incompatibility is not visible - in this case, about the chemical

- 1,032341 drug incompatibilities become known only after their use, when damage to crops becomes noticeable and it will be too late to fix anything. In addition, the use of tank mixtures in production causes certain difficulties associated with calculating doses and weighing the estimated dose of each component, and errors can occur that lead to a decrease in the effectiveness of the mixtures. All tank mixtures are not intended for storage and should be used on the day of preparation. In this regard, it is necessary to use ready-made factory mixtures with a given constant ratio of components.

Among the ready-to-use formulations registered in Russia that contain combinations of betanals with other herbicides, oil dispersion (BETANAL MAX PRO trademark of Bayer Cropscience AG company) described in Eurasian patent EA 018155 B1 (class Α01Ν 43 / 12, published May 30, 2013). The known preparation contains 75 g / l of etofumezat, 60 g / l of phenmedifam, 47 g / l of desmedifam, 27 g / l of lenacil and targeted additives. The biological effectiveness of the drug decreases at low application temperatures: fenmedifam and desmedifam have little control of weeds at such temperatures, and the rest of the active ingredients included in the formulations do not compensate for the action of betanals and therefore can not cope with many weeds, including rape harvest. Even under the recommended conditions of use (optimal weather conditions), the effectiveness of BETANAL MAX PRO against rapeseed drops is not more than 63%, since the amount of lenacil included in it is not enough for the complete death of this weed.

The closest analogue of the invention is a herbicide composition based on metamitron and lenacil, described in UK patent OV 1450365 A (class No. 01 43/58, publ. 09/22/1976, p. 4 of the description). This composition is a so-called tank mixture, which in addition to these active ingredients also contains acetone (solvent) and alkylaryl-polyglycol ether (emulsifier). A working solution is prepared and pre-emergence treatment of beet crops (in the cotyledon phase according to the first wave of weeds) is carried out at a rate of 2.1-2.8 kg / ha (for metamitron) and 0.4-0.6 kg / ha (for lenacyl) . The prepared tank mix is not intended for storage, but in combination with betanals it is characterized by great problems with use.

Thus, the creation of physically and chemically stable finished formulations based on known combinations of active substances, the use of which contributes to the manifestation of increased biological activity, is still an urgent task.

The aim of the present invention is to provide improved biological protection of crops, increasing yields, reducing the cost of agricultural producers to purchase pesticides, increasing the shelf life of drugs under different temperature conditions.

The technical result consists in the creation of a physically and chemically stable suspension concentrate having a high herbicidal effect against an expanded spectrum of monocotyledonous and dicotyledonous weeds, including rapeseed, and which can be used in a wide temperature range.

The object of the claimed invention is a stable suspension concentrate with a herbicidal action based on a mixture of metamitron with lenacil, the particles of which are dispersed in a polar diluent and have an average size of not more than 5 microns, while the total content of these active substances in the concentrate is in the range from 300 to 750 g / l The weight ratio of metamitron and lenacyl is selected from the range (2: 1) - (10: 1).

The active substances of the claimed suspension concentrate are known - see the reference book T11C Rekyabe Mapia1, 14 ⁴¹¹ sbyup. HRCS, IR, 2006: metamitron (p. 685, No. 540), Lenacil (p. 638, No. 504).

Compared with the prototype, the use of a patented suspension concentrate can increase biological efficiency, reduce the burden on the environment, reduce the consumption rate for active substances, eliminate the phytotoxic effect on beets, increase the duration and frequency of use of the drug, and also obtain a drug that is stable during storage.

It was unexpectedly found that the shelf life of the claimed suspension concentrate depends on the degree of grinding of metamitron and lenacil and is at least 24 months. Dispersing these active ingredients to an average particle size of not more than 5 microns not only increases its physical stability, but also improves biological efficiency. By reducing the particle size to the specified size, the penetration of the active substances into the weeds is improved (the assimilation period is reduced to one to two hours), and, as a result, the action speed of the preparation increases, the risk of washing off by rain decreases, the consumption rate for active substances decreases.

Suspension concentrate, having in its composition a predominant fraction of particles with a size exceeding 5 microns, leads to a decrease in physical stability and is stored for no more than 16 months. When stored for more than 16 months, such preparations tend to form thick clay layers that are difficult to resuspend. An increase in particle size leads to their coalescence, followed by precipitation. In this case, the sprayer nozzles become clogged, and the particles of the drug that have fallen on the leaf surface of weeds quickly crystallize, due to which the herbicidal effect is significantly reduced.

If the total content of active substances in the preparation is less than 300 g / l, ger

- 2 032341 bicidal efficacy is significantly reduced. In a preparation with a total content of metamitron with lenacil more than 750 g / l, it is not possible to obtain the desired particle size, as a result of which it has low aggregative storage stability.

Thus, in order to simultaneously comply with the conditions for the best biological efficiency and physical stability, the active substances in the preparation should be contained in an amount of 300 to 750 g / l and have an optimal degree of grinding, namely, the average particle size should not be more than 5 microns.

The claimed suspension concentrate has a double mechanism of action: the metamitron and lenacil included in the preparation are systemic pesticides; the drug is absorbed by both the foliage and the root system of the weed. The active substances, penetrating through the roots and foliage, inhibit the photosynthesis of plants. Weeds die within a few weeks after treatment. The drug has a prolonged effect: it controls new seedlings of weed vegetation for one to two months (depending on weather conditions), which allows to reduce the number of treatments without decreasing biological effectiveness.

The action of the proposed suspension concentrate extends, in particular, to such weeds as veronica (species), small-flowered halinsoga, bird highlander, field mustard, sackcloth (species), Sophia descurania, pharmacy haze, medium starlet, field cabbage, cohia broom, godson common, quinoa (species), gauze (species), shepherd’s bag, black nightshade, pikulnik (species), common bedstraw, garden purslane, chamomile (species), wild radish, blood-red dewdrop, tri-rib, shiritsa (species), walrus purple, field yurt, field violet, millet chicken, rapeseed rape, field torica, bristle (species), full-time field color, self-seeded poppy, field foxtail, ragweed and others.

The suspension concentrate according to the invention may contain, in addition to the diluent, other target additives, such as at least one surfactant, acidity regulator, thickener, antifoam, antifreeze and / or biocide.

Non-ionic, anionic and / or cationic surfactants commonly used in the preparation technology of formulations can be used as surfactants.

Agrochemically acceptable polar diluents such as water, polyglycols and / or their esters are used as diluent.

As a regulator of acidity (pH corrector), citric acid and its salts, maleic acid and other acids can be used.

As a thickener, xanthan gums, polysaccharides, polyvinyl alcohol, polyvinylpyrrolidone, bentonite or silicon dioxide derivatives and synthetic thickeners can be used.

As an antifoam, polydimethylsiloxane can be used. Propylene glycol, glycerin can be used as antifreeze.

As the biocide, in particular, 1,2-benzisothiazolin-3-one and 1,3,5-tris (2hydroxyethyl) hexahydro-1,3,5-triazine or a mixture thereof can be used.

Suspension concentrates can be obtained by the usual method, for example, by grinding a mixture of active substances with a diluent, and surfactants in bead mills to achieve the desired particle size. After grinding, auxiliary additives are added to the suspension - acidity regulator, thickener, antifoam, antifreeze and / or biocide.

Another object of the invention is a method of controlling undesirable vegetation in crops of crops, comprising diluting with water the above suspension concentrate and its subsequent application in effective amounts to weeds to be destroyed and their places of growth. Crops of sugar beet, table or fodder are processed preferably in the post-emergence period - at an early stage of development of weed plants and beets (preferably in the cotyledon phase of weeds). Post-emergence application of herbicides is used both to destroy growing weeds and to prevent their emergence. Preferred drug consumption rates are from 1.2 to 3.5 l / ha. Perhaps 2-fold use of the drug in a wide temperature range from 5 to 30 ° C.

Another object of the invention is the use of a suspension concentrate based on a mixture of metamitron with lenacil to combat rape scavenger in crops.

The following are examples illustrating the invention.

Example 1. Obtaining samples in the form of a suspension concentrate

For testing, samples of suspension concentrate were prepared as follows.

200 g of water, 400 g of metamitron, 80 g of lenacyl, 36 g of a mixture of ethoxylated tristyrylphenol and amine salt of phosphate ethoxylated tristyrylphenol were placed in a reactor. The mixture was thoroughly mixed until a homogeneous suspension was formed and milled in a Όνηο-бис bead mill to a predetermined average particle size. 1.6 g of polysaccharide and 0.8 g of 1,2-benzisothiazolin-3-one, 71 g of propylene glycol, 24 g of polydimethylsiloxane, 2 g of citric acid were added to the resulting product

- 3 032341 also water to 1 liter of the drug. Got sample No. 1.

Samples No. 2-7 (see table. 1) were obtained in a similar way, while the target additives were used the same.

Example 2. Determination of the average particle size in suspension concentrate

Under the average particle size of the active substances in the present invention means that at least 50% of the particles by volume have an average size of not more than 5 microns.

Analysis of the average particle size of the active substances was carried out by laser diffraction. For each sample, we plotted the particle size dispersion using a Ma1ueti MaChsgmhsg 3000 measuring device. The dispersed parameters of the samples are shown in Table. 2. An example of a dispersion graph for sample No. 1 (before storage) is shown in FIG. 1. Particles of active substances in sample No. 1 have the following distribution: 92% of the particles have an average size of 5 microns or less, 50% - 2.16 microns or less, 10% - 0.83 microns or less.

Other physicochemical characteristics of the obtained samples were also determined (see Table 2).

Example 3. Assessment of storage stability

Assessment of the stability of samples No. 1-7 during storage was carried out under various conditions according to international methods.

To assess the possibility of storing drugs for 2 years at a temperature of minus 10 to plus 35 ° C, the following tests were carried out:

1. Test for accelerated storage: the preparations were kept in a thermostat at plus 54 ° C for two weeks (method C1PAC MT 46.3).

2. Frost resistance test: the preparations were kept in a thermostat at minus 15 ° С for 10 days (method C1PAC MT 46.3, C1PAC MT 39.2).

3. Heat aging test: the preparations were kept in a thermostat at plus 45 ° С for 60 days (8gGas1ap15 apb 8res1a1y1e5 Gog R1ap1 Rtobisbop, section 2.2.5).

Repeat tests three times

The viscosity of the preparations, both before and after storage, was determined on a Brookfield viscometer (method C1PAC MT 192), particle dispersion was determined on a laser particle analyzer Layout Macheg51 / eg 3000 (method C1PAC MT 187).

From the above table. The 2 results show that samples 1-3, 5 and 7 are stable and are a viscous opaque liquid both before storage and after. Sample 4, containing less than 300 g / l of active substances with an average particle size of more than 5 μm, exfoliates during storage. Sample 6, containing more than 750 g / l of active substances with an average particle size of more than 5 μm, is also unstable during storage.

Example 4. Assessment of biological effectiveness

Tests of the herbicidal activity of the claimed suspension concentrate was carried out in the field on sugar beet crops, hybrid Λζ мел / а (small plot experiment, RUE Institute for Plant Protection, Minsk region and region). Predecessor: rapeseed.

For testing, samples No. 1-7 were diluted with water and applied in an effective amount to weeds to be destroyed and their places of growth.

The samples used were PILOT, VSK (700 g / l metamitron) by August, BETANAL MAX PRO, MD (75 g / l etofumezat, 60 g / l phenmedifam, 47 g / l desmedifam, 27 g / l lenacyl) by Bayer Cropscience with a consumption rate of 1.5 l / ha (registered consumption rate for these preparations), as well as a tank mixture (Pilot, VSK + Lenacil, SP). The average particle sizes of the active substances in the standards (measurements were carried out according to the method described in Example 2 of the present invention) had the following values: for PILOT - less than 5 microns, for LENACIL - 30-40 microns, for Betanal Max Pro - less than 5 microns.

The size of the plots is 25 m ² , the number of replicates is 4. Vegetative plants were sprayed once with a 1ec1o-16 backpack sprayer, the flow rate of the working fluid was 200 l / ha. Air temperature on the day of processing: + 12 ° C.

During the treatment period, annual weeds had a cotyledon phase - the first pair of true leaves.

Quantitative-species registration of weeds was carried out before treatment (initial weediness), quantitatively-weighted - 14 days after spraying. The abundance and vegetative mass of weeds were recorded in accordance with the Guidelines for conducting registration tests of herbicides in crops of the Republic of Belarus, Soroka S.V., Lapkovskaya T.N., 2007.

The weeds were dominated by such weeds as rape-seed rape, white gauze, shepherd’s bag, rugged mountaineer, ordinary pikulnik, odorless chamomile, fieldweed highlander, field violet, chicken millet, thrown backwood, yellow sow thistle, rough mountaineer, blue cornflower, other wheatgrass .

Evaluated the effectiveness of patentable suspension concentrate for certain types of weeds (table. 3).

From the table. 3 shows that samples 1-3, 5 and 7 reduce the number of weeds prevailing in crops

- 4 032341 up to 98%. At a consumption rate of 1.5 l / ha, the biological efficiency of sample 2 was 90-98%, and that of standard 1 was 75-85%. Standard 2, containing the same total consumption rate for active substances as sample 2, has an efficiency of 80-85%. Standard 3, taken at a consumption rate of 1.5 l / ha, suppresses rapeseed carrion by no more than 65%. Samples 4 and 6, containing less than 300 g / l and more than 750 g / l of active substances, respectively, are less effective and reduce the number of weeds to no more than 78%.

During visual observation of sugar beet crops after processing, the phytotoxic effect of the claimed concentrate was not established in the applicable consumption rates for the growth and development of sugar beets.

Thus, the present invention allows to obtain stable suspension concentrates that do not alter the physicochemical parameters over a long shelf life and which can be effectively applied over a wide temperature range with respect to an expanded spectrum of weed plants, including spring weeds such as rapeseed.

Table 1. Prepared samples in the form of a suspension concentrate

Sample Number The content of metamitron, g / l The content of Lenacil, g / l The ratio of metamitron to lenacil The total content of active substances, g / l one 400 80 5: 1 480 2 480 120 4: 1 600 3 200 100 2: 1 300 four 200 50 4: 1 250 five 681.8 68,2 10: 1 750 6 650 130 5: 1 780 7 455 65 7: 1 520

Table 2. Assessment of the stability of the suspension concentrate during storage

Sample Type of test Appearance Viscosity at 20 ° С, MPa * s Density at 20 ° C, kg / m ’ pH Dispersion, the content of particles with an average size of not more than 5 microns,% one Before storage Viscous opaque liquid 730 1139 5.1 92 After storage at +54 ^and C for 14 days  ”- 725 1140 5.1 92 After storage at minus 15 ° C for 10 days 730 1139 5,0 92 After storage at +45 ° C for 60 days - ·· - 730 1139 5,0 92 2 Before storage Viscous opaque liquid 870 1175 4.7 98 After storage at +54 ° C for 14 days 850 1176 4.6 97 After storage at minus 15 ° C for 10 days 850 1175 4.7 97 After storage at +45 ⁽¹ C for 60 days  ” 860 1176 4.7 97 3 Before storage Viscous opaque liquid 580 1073 4.9 58 After storage at +54 ° C for 14 days - 581 1074 4.8 55 After storage at minus 15 ° C for 10 days - 580 1074 4.9 55 After storage at +45 C for 60 days 580 1073 4.8 55 four Before storage Viscous opaque liquid 570 1069 4.7 42 After storage at +54 ° C 490 1065 4.7 37

- 5 032341

within 14 days After storage at -15 ° C for 10 days Exfoliated fluid. - - - - After storage at +45 ° C for 60 days Exfoliated fluid. Dense sediment at the bottom - - - - five Before storage Viscous opaque liquid 1100 1201 4.6 85 After storage at +54 ° C for 14 days - „- 1105 1198 4.7 86 After storage at minus 15 ° C for 10 days 1104 1203 4.6 87 After storage at +45 ° C for 60 days - "- 1116 1215 4.6 84 6 Before storage Viscous opaque liquid 860 1184 4.7 39 After storage at +54 ° C for 14 days Viscous liquid with a transparent peeling layer at the top 950 (after homogenization) 1153 4.7 thirty After storage at minus 15 ° C for 10 days Exfoliated fluid. At the bottom - sediment - - - - After storage at +45 ° C for 60 days - - - - - 7 Before storage Viscous opaque liquid 795 1135 4.8 88 After storage at +54 ° C for 14 days - ,, - 798 1136 4.7 87 After storage at minus 15 ° C for 10 days 795 1136 4.8 88 After storage at +45 ° C for 60 days 795 1135 4.7 88

Table 3. The effect of post-emergence herbicides on the prevailing weed species in sugar beet crops (accounting 14 days after processing)

Option The consumption rate of the drug, l / ha [consumption rate for substances metamitron + lenacil, g / ha] The reduction in the number of weeds,% to control Mary White Highlander grungy Shepherd's bag Rapeseed drop Shiritsa thrown back Control without treatment 30 pcs / m ² 12 pcs / m ² 10 pcs / m ² 43 pcs / m ² 27 pcs / m ² Sample 1 2 [800+ 160] 92 90 95 95 98 Sample 2 1.5 [720+ 180] 95 90 97 97 98 Sample 3 2 [400 + 200] 86 87 87 85 87 Sample 4 3.5 [700+ 175] 72 60 60 75 77 Sample 5 1.2 [818.2 + 81.8] 95 93 95 90 95 Sample 6 1.2 [780+ 156] 70 62 62 78 70 Sample 7 1.8 [819 + 117] 92 90 90 91 93 Pilot, VSK (reference 1) 1.5 [1050 g / ha metamitron] 85 80 82 75 85 Tank mixture Pilot, VSK + Lenacil, SP (reference 2) 1 l / ha + 0.25 kg / ha [700 + 200] 85 82 82 80 85 Betanal Max Pro, MD (reference 3) 1,5 85 85 85 65 85

Claims (7)

CLAIM 1. A stable suspension concentrate with a herbicidal action based on a mixture of metamitron with lenacil, particles of which are dispersed in a polar diluent and have an average size of not more than 5 microns, while the total content of these active substances in the concentrate is in the range from 300 to 750 g / l. 2. The suspension concentrate according to claim 1, in which the weight ratio of metamitron and lenacyl is in the range from 2: 1 to 10: 1. 3. The suspension concentrate according to claim 1, in which agrochemically acceptable diluents are used as the polar diluent, in particular water, polyglycols and / or their esters. 4. The suspension concentrate according to claim 1, additionally containing at least one surfactant, acidity regulator, thickener, antifoam, antifreeze and / or biocide. 5. A method of combating unwanted vegetation in crops of crops, comprising diluting with water a suspension concentrate according to any one of claims 1 to 4 and its subsequent application in an effective amount to the weeds to be destroyed and their places of growth. 6. The method according to claim 5, in which the crop is a sugar beet, table or fodder. 7. The use of suspension concentrate according to claim 1 for combating rape seedlings. - 6 032341