RU2741844C1 - Herbicide composition and method for control of weeds - Google Patents

Abstract

FIELD: agriculture.SUBSTANCE: invention relates to plant protection products and can be used in agriculture to combat dicotyledonous and cereal weeds in corn crops. The synergistic herbicidal composition contains mesotrione (I), nicosulfuron (II) and picloram (III). The weight ratios of the components I: III: II are in the range (20÷40):7:(10÷20). For preparation of formulations, it additionally contains agrochemically acceptable excipients such as fillers, diluents, surfactants, oils, acidity regulators, thickeners and / or antifoams. The invention can be carried out in the form of oil dispersion, suspension concentrate or water-dispersible granules. To combat unwanted vegetation in corn crops, present composition is applied at agrochemically acceptable application rates to weeds to be destroyed and their growing areas.EFFECT: said invention provides improved biological protection of corn crops against a wide range of weeds, does not cause resistance in weeds, and allows increasing yield of corn.7 cl, 4 tbl, 2 ex

Description

The invention relates to plant protection agents, more specifically to a synergistic herbicidal composition based on mesotrione, nicosulfuron, picloram, as well as a method for controlling weeds using this composition. The present invention can be used in agriculture to control dicotyledonous and cereal weeds in cereal crops, in particular, corn, sorghum, millet.

Weed control is an ongoing problem in agriculture. The main harm caused by weeds is a sharp decline in yields and a deterioration in the quality of products. Now on the market for plant protection chemicals there are a large number of herbicidal preparations (both single-component and combined). However, not all of the recommended herbicides are effective in addressing weed problems. This is due not only to the presence of hard-to-kill weeds, for example, root suckers, but also to the emergence of resistant biotypes of weeds. Therefore, the development of new, more effective and safer herbicide combinations is still an urgent task.

A herbicidal composition for protecting corn crops is known from the prior art, containing florasulam and nicosulfuron in a weight ratio of 2: 1 to 180: 1 (RF Patent RU 2574742 C1, class A01N 47/28, publ. 10.02.2016, bull. No. four). However, this composition is not effective enough against some weeds, in particular, hairy peas, bindweed, knotweed, cocklebur, garden sow thistle, field sow thistle, field bindweed, Tatar lettuce and others.

In the Chinese application CN 103636607 A (class A01N 41/10, publ. 03/19/2014), a herbicidal composition for protecting corn crops based on picloram and mesotrione with a weight ratio of 1:60 to 60: 1 is described, which is made in the form of a suspension concentrate ... However, the specified combination of active substances is ineffective against annual and perennial cereals, and also ineffective against some annual dicotyledonous weeds.

The closest analogue of the invention is the herbicidal composition described in patent EA 017226 B1 (class A01N 25/22, publ. 30.10.2012). The known combination contains mesotrione and nicosulfuron as active substances in a weight ratio of 10: 1 to 1:10. This document also describes a method for controlling weeds in corn crops, which consists in treating their growing areas with an effective amount of the specified composition. On the basis of the patented combination, a commercial preparation in the form of an oil dispersion, ELUMIS (trademark of Syngenta), was created and registered. This drug is not effective enough against malicious root-sprouting weeds (in particular, thistles, sow thistles, field bindweed), bedstraw and others.

The aim of the present invention is to provide improved protection of crops of grain crops against a wide range of weeds, increasing productivity.

The technical result consists in creating a synergistic composition effective against annual and perennial dicotyledons, as well as cereal weeds that infest cereal crops, in particular, corn.

The object of the present invention is a herbicidal composition containing mesotrione (I) and nicosulfuron (II) in a weight ratio (1 ÷ 4): 1, which, according to the invention, includes an additional herbicide - picloram (III), while the weight ratio of components I: III : II are in the range (20 ÷ 40): 7: (10 ÷ 20), i.e. the ratio of the components I: III is selected from the range of values (20 ÷ 40): 7, and the ratio III: II - from the range of values 7: (10 ÷ 20).

The inventors have surprisingly found that a synergistic effect appears in the indicated weight ranges, i. E. the ranges of ratios of active substances were found, at which such a composition is synergistically effective.

The claimed composition is the most effective and has a wider spectrum of action against annual and perennial weeds, including cereals, in comparison with the known combinations / preparations. In addition, the combination of three active substances with different mechanisms of action from different chemical classes in the herbicidal composition does not cause resistance in weeds.

The active ingredients of the patented combination are known from The Pesticide Manual, 14 ^th edition, BCPC, UK, 2006: mesotrione (p. 675, No. 533), nicosulfuron (p. 751, No. 594), picloram (p. 838, no. 665).

Mesotrione is a member of a class of HPPD inhibitors that work by inhibiting the plant enzyme 4-hydroxyphenylpyruvate dioxygenase. In plants, HPPD is required for the biosynthesis of carotenoids. Carotenoids, in turn, protect chlorophyll from damage by sunlight. Mesotrione prevents the formation of carotenoids, as a result of which chlorophyll decomposes, which leads to the death of the plant.

Nicosulfuron inhibits the production of the enzyme acetolactate synthase, which is involved in the synthesis of essential amino acids: leucine, isoleucine and valine, which occurs in chloroplasts. Violation of the biosynthesis of amino acids leads to a deficiency of proteins, which causes a violation of the process of cell division, growth arrest and the subsequent death of weeds.

Pikloram is a hormone-like herbicide. A synthetic form of growth hormone, the herbicide replaces the plant's natural hormones by blocking their function. Oversaturation with synthetic hormones leads to significant disturbances in the growth processes in plants and their death.

The claimed herbicidal composition, hitting the leaves of the weed and the soil as a result of spraying, quickly spreads throughout the plant. The slowdown in the growth of weeds occurs within a few hours after the absorption of the combined pesticide by them: their points of growth become discolored, then the whole plant becomes discolored, and tissues die off. The complete death of weeds occurs within 1-2 weeks from the moment of treatment, depending on weather conditions and the species composition of the weeds. Overgrown or less sensitive to the herbicide weeds do not die, but they stop further development and do not affect the crop yield. The claimed composition well destroys those weeds that have already sprouted or are germinating at the time of treatment, and also prevents the appearance of subsequent waves of weeds (it has a soil effect).

The effect of the proposed herbicidal composition extends, in particular, to such weeds as ragweed (species), stork cicut, medium starlet, hairy vetch, small-flowered galinsoga, amphibian mountaineer, field mustard, mountaineer (species), field peas (pelushka), delphinium (species), cocklebur, common dope, medicinal smoke, Theophrastus rope, weed hemp, clover (species), lying cinquefoil, quinoa (species), field buttercup, white gauze, Canadian small petals, whorled molluscum, field thistle, medicinal dandelion, buttercup (species), black nightshade, prickly nightshade, Carolina nightshade, common pickleberry, garden purslane, tenacious bedstraw, sunflower (carrion), field radish, white radish, common rape, Iberian hodgepodge, bird knotweed, perforated three-ribbed wormwood southern, rank (species), sorrel (species), overturned beetle, beetle gmindoid, white beetle, paniculate beetle, yarotka (species), bindweed left, field thistle, field horsetail (from spores), thistle (species), Indian eleusina, barnyard grass (chicken millet), gray bristle, green bristle, hairy millet, blood-red crabgrass, Aleppo sorghum (humai), wheatgrass and others.

The claimed composition can be used to protect the following cereals: corn, millet, sorghum and others.

Suitable for this combination of herbicides are both liquid formulations (in particular, oil dispersion, suspension concentrate, etc.) and solid formulations (in particular, water-dispersible granules). To obtain these formulations, the herbicidal composition additionally contains agrochemically acceptable auxiliary substances such as fillers, diluents, oils, surfactants, acidity regulators, thickeners and / or defoamers.

Water-dispersible granules (WDG) are spherical or cylindrical agglomerates. Before use, EDG is dispersed in water to form a homogeneous suspension. Granules can be obtained by various known granulation methods from a mixture consisting of a mixture of active substances with a filler, surfactants, and, if necessary, adding an antifoam and other auxiliary substances.

Suspension concentrate (SC) is a concentrated suspension of active ingredients in water in the form of a viscous liquid mass. Before use, SC is diluted in water. A suspension concentrate is prepared by grinding a mixture of active ingredients with a diluent, surfactant and antifoam in bead mills until the required solid particle size is achieved. After milling, an acidity regulator and / or thickener is added to the suspension, if necessary.

Oil dispersion (MD) is a preparative form in which the solid phase (particles of active active ingredients) are dispersed in the oil phase. Vegetable oils, methylated vegetable oils or mineral oils are generally used as the oil phase. Before use, a working solution is prepared from MD by adding the drug to the required amount of water. Fine grinding of the mixture to obtain a dispersion is prepared by joint grinding of the active substances and oil and one or more additional auxiliary components, such as emulsifiers and rheological stabilizers (thickeners).

Preferred fillers are, for example, silicon dioxide, kaolin, bentonite, aerosil, lactose, natural sugars, sodium sulfate, trisodium phosphate, or mixtures thereof.

Mineral / vegetable oil, oil methyl alcohols and / or water can be used as diluent.

As surfactants, nonionic, anionic and / or cationic surfactants that are commonly used in the preparation of preparative forms, acting as a wetting agent, dispersant and / or emulsifier, in particular, oxyethylated or propoxyethylated alkylphenol, polyoxyethylated alcohol or amine, ethoxypropoxyblock copolymer sulfate or phosphate of polyoxyethylated alcohol or their salts, ethoxylated tristyrylphenol, sulfate or phosphate of ethoxylated or propoxylated tristyrylphenol or their salts, alkylsulfate or arylsulfate or their salts, alkylsulfonate or arylsulfonate, sulfonate sulfonate or their salts, lignosulfinated alkylsulfonate or its salts or mixtures thereof, polymeric surfactants based on acrylates and their derivatives.

As acidity regulators can be used salts of alkali and alkaline earth metals (in particular, carbonates), citric acid.

Polydimethylsiloxane can be used as an antifoam agent.

As rheological stabilizers (thickeners), xanthan gums, polysaccharides, polyvinyl alcohol, polyvinyl pyrrolidone, bentonite or silica derivatives, and synthetic thickeners can be used.

The content of excipients in formulations can vary within wide limits.

Another object of the invention is a method for controlling undesirable vegetation in corn crops, which involves treating the weeds to be destroyed and their growing areas with the above herbicidal composition, previously diluted with water, at agrochemically acceptable application rates.

Plants can be processed as a ready-to-use formulation, a “tank mix” prepared in a tank just before spraying, or as a so-called “ready-to-use mix” (plant mix, twinpacks, etc.).

The herbicidal composition (or preparation based on it) according to the invention is applied to unwanted vegetation in the post-emergence period, i.e. at an early stage of development of weeds and maize.

Below are examples and results of biological tests.

Example 1. Evaluation of the synergistic effect of the composition in laboratory conditions

The experiment was carried out in a laboratory of artificial climate with the following operating mode of the chambers: the duration of the day - 16 hours, nights - 8 hours, daylight illumination -15000 Lx, air temperature - 20 ° C, relative humidity - 75%.

White gauze, gray bristles were used as test objects. These plants are representatives of families that include profiling weeds in agroclimatic zones of corn growing.

For the experiment, the active substances (mesotrione, nicosulfuron and picloram with different weight ratios) were pre-dispersed in mineral oil. Received 8 samples. Before the treatment of plants, the obtained samples of the oil dispersion were diluted with water to obtain working solutions.

Test plants were grown in pots filled with sod-podzolic soil, sand, and peat. Next, the plants were culling, removing the largest and smallest specimens.

Test plants were treated in the second leaf phase. The test plants were treated with a LU 1.01 laboratory setup with a VIZR monodisperse disk nebulizer.

The land mass of plants was counted 10 days after treatment. The herbicidal effect (BE _fact. ) Of the variants was assessed by the percentage of decrease in the ground biomass of the treated plants relative to the control, where 0 corresponds to the absence of damage, and 100 corresponds to the complete destruction of the test plant. The results are shown in Table 1.

The effectiveness for a mixture of three biologically active substances in% was calculated using the Colby formula and was determined as follows (COLBY LR "Calculating synergistic and antagonistic responses of herbicide combinations" ("Calculation of the synergistic and antagonistic expected effects of herbicide mixtures"; Weeds 15, pp. 20-22 , 1967), (LIMPEL et al. 1962 "Weeds control by certain combinations" Proc. NEWCL. Vol. 16, pp. 48-53):

BE _calc. = (X + Υ + Ζ) - ((Χ × Υ + Χ × Ζ + Υ × Ζ) / 100) + (Χ × Υ × Ζ / 10000)

BE _calc. - calculated biological efficiency with the combined use of active ingredients Χ, Υ, Ζ.

X is the biological effectiveness of active ingredient X (mesotrione) at the same consumption rate used in the mixture.

Υ - biological effectiveness of the active ingredient Υ (nicosulfuron) at the same consumption rate that is used in the mixture.

Ζ - biological effectiveness of the active ingredient Ζ (picloram) at the same consumption rate that is used in the mixture.

Synergy index (BE _fact. / BE _calculated ), which has a value greater than 1, indicates synergy. An IS of 1 indicates additivity. When the IP is less than 1, then antagonism is found.

Analysis of the experimental data shown in Table 1 showed the following. For a composition containing active substances in the claimed ratios (samples 1-6), the actual biological effectiveness is higher than that calculated by the Colby formula, and the synergism index is greater than 1. i. there is a synergistic effect. The actual biological efficiency (BE _fact. ) Of the composition in relation to annual dicotyledonous weeds (for example, mari white) is 100%, and in relation to annual cereal weeds (for example, gray bristles) - 95%.

For the composition with the ratios of active substances outside the stated limits (samples 7-8), there is no synergy (synergism index is less than 1). The actual biological effectiveness of the composition is lower: in relation to white mari (annual dicotyledonous plant) does not exceed 80%, and in relation to gray bristles (annual cereal plant) - does not exceed 74%.

Example 2. Evaluation of the biological effectiveness of the composition and the yield of corn

Tests of the herbicidal activity of the claimed composition were carried out in the field on crops of corn, a hybrid "Krasnodar 291 AMV" (small-plot experiment).

Place of the experiment: Russian Federation, Krasnodar Territory, the city of Krasnodar, experimental field of VNIIBZR.

To carry out the experiment, we used samples of the herbicidal composition in the form of a ready-made oil dispersion, according to the invention, at various ratios of active ingredients. Before the treatment of plants, these samples were diluted with water to obtain working solutions.

In accordance with the requirements for registration tests of pesticides, the drug Elumis, MD (75 g / l mesotrione + 30 g / l nicosulfuron), produced by Syngenta, was chosen as a standard.

Vegetative plants were sprayed once with a Pulverex knapsack sprayer. The phase of development of corn plants at the time of processing is 4-5 leaves. Working fluid consumption - 200 l / ha.

Weed plants were counted 30, 45 days after treatment and before harvesting.

Accounting methodology: by quantitative-weight method; in accordance with the “Methodological guidelines for registration tests of herbicides in agriculture” (St. Petersburg, 2013).

In the crops on which the research was carried out, prevalent weeds such as barnyard grass, white gauze, fume-grass, highlander, common stork, field bindweed, gray bristles, ragweed, upturned aphid, cocklebur, tenacious bedstraw and others.

During the spraying period, annual dicotyledonous weeds had 3-5 leaves, annual cereals - 2-4 leaves - tillering.

The average results of assessing the sensitivity of various types of weeds to the composition are presented in table 2.

Additionally, the effectiveness of the patented composition for certain types of weeds was assessed (see Table 3).

From the presented data in Tables 2 and 3, it can be seen that the herbicidal composition with the weight ratios of the components I: III: II equal to (20 ÷ 40): 7: (10 ÷ 20) surpasses the reference (Elumis preparation) in biological efficiency: after 30 days after treatment, in relation to annual dicotyledonous weeds, complete destruction is observed, in relation to annual cereal weeds - a decrease to 94%. In addition, the herbicidal composition according to the invention most effectively fights against perennial dicotyledonous weeds, while exhibiting a soil effect: the biological effectiveness before harvesting reaches 87%.

The yield was determined by weighing the grain obtained from 1 ha of the treated surface, and comparing the value obtained with the value obtained in the control. The use of the patented herbicidal composition in the claimed ratios of active substances on corn crops can increase its yield by 29-35% (compared to the standard), see table. 4.

Field tests carried out on corn crops have shown that the herbicidal composition according to the present invention is superior in efficiency to its counterparts, especially in terms of suppressing perennial weeds.

Claims (7)

1. Synergistic herbicidal composition containing mesotrione (I) and nicosulfuron (II), characterized in that the composition includes an additional herbicide - picloram (III), while the weight ratio of components I: III: II is in the range (20 ÷ 40): 7: (10 ÷ 20). 2. A synergistic herbicidal composition according to claim 1, characterized in that for the preparation of formulations, it additionally contains agrochemically acceptable auxiliary substances such as fillers, diluents, surfactants, oils, acidity regulators, thickeners and / or antifoams. 3. A synergistic herbicidal composition according to claim 2, characterized in that it can be presented in the form of a liquid formulation. 4. A synergistic herbicidal composition according to claim 3, characterized in that it can be in the form of an oil dispersion or suspension concentrate. 5. A synergistic herbicidal composition according to claim 2, characterized in that it can be presented in the form of a solid formulation. 6. A synergistic herbicidal composition according to claim 5, characterized in that it can be in the form of water-dispersible granules. 7. A method of combating undesirable vegetation in corn crops, characterized in that the weeds to be destroyed and the places of their growth are applied with the herbicidal composition according to any one of claims. 1-6 at agrochemically acceptable consumption rates.