CS226445B2 - Seed treating composition - Google Patents

Abstract

A liquid slurry seed treater formulation containing one or more pest control agents and a high solids acrylate copolymer emulsion adhesive sticker in addition to one or more suspending agents and surface active agents, water, and, optionally, other diluents, adjuvants or other additives, is applied to seeds to yield seeds having an adherent coating in which the pest control agent is dispersed.

Description

The invention relates to a method of protecting crops from plant pests, in particular from pests which attack crop seeds and seedlings.

For many years, various methods have been developed that are used to control crop pests that attack seeds and seedlings. Prior to the use of different seed treatment agents, several alternative methods were used, such as sterilizing the soil by single or multiple application of the pesticide just before or just after sowing. Today, the most commonly used method for the protection of agricultural crops in the form of seeds or seedlings is the use of seeds treated with pesticides. In particular, this method is used for cereals or plant crops. In general, seed companies or pesticide manufacturers prepare treated seeds which are then commercially available to growers. The use of seeds treated with pesticides is particularly advantageous in that it places the pest control agent at the point where the pest infestation occurs and thus eliminates the waste amounts required for the treatment of cultivated areas.

Treatment of the seeds with systemic pesticidal agents allows the protection of the seeds themselves, emerging roots and growing seedlings vulnerable to soil insects and nematodes and soil-grown seedlings, which are particularly susceptible to attack by above-ground insects and other pests.

The application of crop seed pest control means is carried out in a multi-step process by first applying a coating of adhesive to the seeds, then a pesticide composition in the form of a dust that adheres to the adhesive surface of the coating. Subsequent coating of the adhesive is often still necessary to prevent loss of pesticide dust by abrasion or abrasion.

Recently, treatment compositions have been developed which include an adhesive adhesive, generally hydroxypropylcellulose or a polyvinyl acetate emulsion directly in the pesticidal composition itself, allowing the adhesive and pesticide to be applied to the seeds in one step. While the use of these compositions greatly simplifies the process of placing the pesticide coating on the seeds, the treated seeds prepared with the compositions tend to dust. This arises from coatings which are scraped off from seeds coming into contact with each other during and after drying. In addition to the fact that this dusting is unpleasant for persons handling the treated seeds, the exposure of these people to the adverse effects of pesticides increases.

According to the process of the present invention, substantially less powdery seed treated with pesticides is prepared by using a new liquid (aqueous) suspension composition to prepare the treated seed. The present invention relates to a novel seed treatment composition, a method of treating seeds and seedlings before crop pests by applying to the seed a suspension composition, the coated seed is dried to remove excess liquid, and seeds containing an adhesive, pesticide-containing coating are prepared.

The present invention provides a seed treatment composition by applying an aqueous suspension to plant seeds to protect seeds and seedlings from insects or nematodes, which comprises up to 50% by weight of insecticide or nemiaitocide,

0.5 to 15% by weight of an adhesive adhesive emulsion based on a 2-ethylhexyl acrylate copolymer with a solids content of 60 to 70% by weight and a viscosity of 0.5 to 4.0 Pa. s at 25 ^° C, up to 70% by weight of water and up to 30% by weight of inert ingredients other than water, the sum of all components being 100% by weight. Suitable multipolymer acrylate emulsions are commercially available under the trade names Vinrez 6201 and Vinrez 6202 from Union Oil Company of California, Union Chemicals Division, Petrochemical Group, 67 Walnut Avenue, Clark, New Jersey 07066, USA.

The compositions of the invention are stable to long-term storage, generally longer than one year. Aggregation of substances during storage is minimal. The components which are separated are readily redispersed by shaking or stirring.

The pesticide-treated seeds are prepared by applying the seed treatment suspension to the seeds, after which the treated seeds are dried to remove excess liquid and adherent coating on the seeds, wherein the pest control agent is dispersed in the adhesive coating. The pest control agent contains 0.1% to 6% of the total weight (seeds plus coating) of the treated seimen. The coating is resistant to abrasion or abrasion of the active pesticide, does not substantially reduce the rate of germination of the seeds, and provides active pesticide levels sufficient to protect against crop pests.

It will be understood that various pesticide active agents against insects and nematodes can be used in the present invention. Agents capable of systemic action are particularly preferred for use herein. A particularly preferred systemic insecticide / nematicide is 2,3-dihydro-2,2-dimethylbenzofuran-7-ylmethylcarbamate ("carbofuran"). It will be understood that fungicidal agents may also be added to protect the seeds from fungal attack against which the insecticidal and / or nematicidal agents are not sufficiently effective.

Seeds treated with liquid suspending compositions may be prepared by mixing an acrylic copolymer adhesive emulsion adhesive with

(ii) a finely divided solid pesticidal composition useful in the preparation of granular pesticides; or (iii) an aqueous liquid pesticide composition; and (i), (ii) and, where appropriate, (iii) with one or more suspending agents and surfactants, water and other diluents, additives or other ingredients.

Suspending agents effective in the process of the invention include xanthan gums (complex polysaccharides of molecular weight above one million), purified colloidal, sodium modified montmorillonites, and organically purified clays.

The surfactants may be nonionic, cationic or anionic. Nonionic polyethylene glycol ethers and anionic surfactants such as ester-free organic phosphoric acids or sodium sulfosuccinic acid dioctyl ester have been found to be particularly suitable. It is understood that nonionic, cationic and anionic surfactants can also be used.

When carbofuran is used as the active pesticidal ingredient, the seed treatment composition of the invention is preferably prepared from a solid carbofuran-based composition or a liquid aqueous carbofuran composition.

A typical solid carbofurah based composition contains about 75% by weight of the active ingredient, for example,% w / w

carbofuran, technical (95% purity) 79.50 anionic wetting agent 1.00 clay thinner 11.00 oil dusting agent 0.80 anionic clay dispersion agent 5.00 talc thinner 2.70 total 100.00

Other solid carbofuran-based compositions include those containing about 80%, 85%, and 90% by weight of the active ingredient:

Carbofuran 80% solid base % w / w carbofuran, technical 84.16 anionic wetting agent 1.06 clay thinner 8.62 oil dusting agent 0.85

% w / w

anionic clay dispersing agent 5.31 total 100.00 Carbofuran 85% solid base % w / w carbofuran, technical 88.54 anionic wetting agent 1.00 clay thinner 5.06 oil dusting agent 0.40 anionic clay dispersion agent 5.00 total 100.00 Carbofuran 90% solid base % w / w carbofuran, technical 93.75 clay thinner 3.25 anionic wetting and dispersing agent 3.00 total 100.00

An aqueous liquid carbofuran composition comprising from 100 g / l to 500 g / l carbofuran containing, for example, by weight:

(a) 8 to 60% solid carbofuran-based formulation containing 75 to 90% by weight of cairbofuran;

b) 0.5 to 8% of a nonionic emulsion agent,

c) 0.01 to 20% of a suspending agent,

d) 0.005 to 0.01% of an anti-foaming agent,

(e) water.

Carbofuran is present in an amount ranging from 100 g / l to 500 g / l of the aqueous liquid composition.

Common aqueous liquid formulations of carbofuran include the following:

Carbofuran 100 liquid composition w / w%

carbofuran 75% solid base 11.73 emulsifying agent 2.00 suspending agent 0.18 bactericidal agent 0.20 anti-foaming agent 0.01 kaolin clay 18.00 water 67.88 total 100.00

it contains about 100 g / l (88 g / kg) of carbofuran.

Carbofuran 200 liquid composition w / w%

carbofuran 75% solid base 23.30 emulsifying agent 2.00 suspending agent 0.14 bactericidal agent 0.20 anti-foaming agent 0.01 kaolin clay 12.00 water 62.35 total 100.00 It contains about 200 g / l (174 g / kg) of carbofuran. Carbofuran 300 liquid formulation % w / w carbofuran 75% solid base 35.80 emulsifying agent 2.00 suspending agent 0.12 bactericidal agent 0.20 anti-foaming agent 0.01 kaolin clay 4.00 water 57.87 total 100.00 contains about 300 g / l (269 g / kg) of carbofuran. Carbofuran 400 liquid formulation % w / w carbofuran 75% solid base 46.80 emulsion agent 2.00 suspending agent 0.08 anionic wetting agent 0.50 bactericidal agent 0.20 anti-foaming agent 0.01 kaolin clay 2.00 water 48.41 total 100.00 contains about 400 g / l (351 g / kg) of carbofuran. Carbofuran 500 liquid formulation % W / w carbofuran 75% solid base 56.90 emulsion agent 3.00 suspending agent 0.02 anionic wetting agent 1.00 bactericidal agent 0.10 anti-foaming agent 0.01 water 37.97 50% aqueous sulfuric acid 1.00

total 100.00 pH 5.78, containing about 500 g / l (427 g / kg) of carbofuran.

А

The preparation of liquid suspension compositions for seed treatment is described in the following examples, which are intended to illustrate but not limit the invention. The acrylate copolymer of emulsion "X" contains 63% to 65% solids and the viscosity ranges from 0.8 to 3.0 Pa. It is commercially available under the name Vinrez 6201 of Union Oil Company of California, Union Chemicals Division, Petrochemical Group, 67 Walnut Avenue, Clark, New Jersey 07066, USA.

The acrylate copolymer of emulsion Y contains 63 percent to 65 percent solids and has a viscosity ranging from 1.5 to 3.5 Pa. . s, commercially available from Union Oil Company under the name Vinrez 6202.

Example 1

Preparation of seed-saving agent from liquid carbofuran composition (composition 1, see Table 1)

In a 120 ml wide-necked flask was placed 10.0 grams of acrylate emulsion "X" and 90.0 grams of an aqueous liquid formulation containing 400 grams / liter of carbofuran. Close the flask and shake mechanically for 10 minutes.

Examples 2 to 4

The seed treatment compositions of these Examples (Formulas 2-4) and Comparative Formulas A-F were prepared as described in Example 1 using the ingredients listed in Tables 1 and 3 in the proportions indicated.

Example 5

Preparation of seed treatment composition from solid carbofuran-based composition (composition 5, see Table 2)

Rhodamine V (4.0 g) was added to 350.2 g of water and the mixture was stirred at a slow speed for 15 minutes. 0.1 g of dimethylsiloxane, 50 g of phosphoric acid and 10.0 g of ethylene-propylene oxide copolymer are added to this mixture. The mixture was stirred at a slow rate for 20 minutes. An acrylate copolymer of emulsion X (100.0 g) was then added and the mixture was stirred at a moderate speed for 2 to 3 minutes. 0.6% w / w xanthan polysaccharide gum (116.7 g) was added and the mixture was stirred at medium speed for 2 to 3 minutes. Solid carbofuran-based formulation (414.0 g) was added and the mixture was stirred at high speed for 15 minutes. The resulting liquid suspension composition is screened through 100 mesh screens to remove any clumps. The pH of the composition is 8.0, its viscosity measured in Zahn's dish # 3 is 20 seconds, and the composition contains 360.7 g of carbofuran.

Examples 6 to 12

The seed treatment compositions of these Examples and Comparative Formulas G and H were prepared as in Example 5 using the ingredients listed in Tables 2 and 4.

Samples of selected formulations are placed in 250 ml wide-neck flasks and a storage stability test is performed. One sample of each formulation is stored at room temperature and the other sample is stored at 50 ° C. The amount of phase separation, solids deposition and the tendency of the compositions to gel are observed. Observations are made periodically 1, 3, 5 and 8 months after the beginning of storage. Tables 5 and 6 show the storage stability of the compositions.

Example 13

Treated wheat with composition No. 5. (Seed treatment share k)

Composition No. 5 (Example 5) 6.75 g was added to 293.25 g Yorkstar wheat seeds in a wide-neck flask. Mix both ingredients with a spatula until the seeds are moist. The flask was capped and placed on a mechanical shaker for 4 minutes. The treated seeds are then placed in an evaporation dish and allowed to air dry for 72 hours. The calculated amount of carbofuran on the seeds is 0.7%. It has been found that 0.0009 g of dust can be collected from 20 g of treated seeds. The amount of dust is determined by placing 20 g of treated seeds in a Kjeldahl flask coupled to a rotary evaporator. A special glass device prepared from a 5.5 cm glass vessel with a helical top and a bottom replaced by a standard ground-glass joint is placed in the outlet of the Kjeldahl flask. The flask cap is perforated with a 1.6 mm hole. A weighed 5.5 cm Whatman No. 1 filter paper is placed on the cap and used to close the open end of this special glass apparatus. The Kjeldahl flask inlet is connected to an air inlet supplying 9000 ml / min which is controlled by a flow meter. The rotary evaporator was connected for 10 minutes and an air stream was passed through the rotating seeds and then through a filter paper. The weight gain of the filter paper during this operation represents dust from a 20 g seed sample.

The properties of wheat treated with these compositions 1 to 5 and comparative compositions A to H are summarized in Table 7.

Example 14

Treatment of barley seeds with composition No 5 (seed treatment share n)

Composition 5 (Example 5) (6.75 g) was added to 293.25 g of Schuyler barley seeds placed in a wide-necked flask, mixed with a spatula until the seeds were wet. They were then placed in an evaporating dish and allowed to air dry for 72 hours, calculated as 0.7% of the seed carbofuran, and it was found that 0.0002 g of dust could be collected from 20 g of seeds. and Comparative Examples G and H are summarized in Table 8.

Example 15

Treatment of corn seeds with composition No. 5 (seed treatment q share) in

Formulation No. 5 (Example 5) (14.19 g) was added to 285.81 g of field corn seeds placed in a wide-necked flask, mixed with a spatula until the seeds were wet, capped and placed on a shaker for 4 minutes. The treated seeds were placed on an evaporating dish and allowed to air dry for 72 hours.The calculated amount of carbofuran on the seeds was 1.5% It was found that 0.0003 g of dust could be collected from 20 g of seeds. 5 and comparative means G and H are summarized in Table 9.

TABLE 1

Seeds treated with compositions prepared from carbofuran aqueous liquid compositions

Resource,% 1 2 3 4 carbofuran, 400 g / l liquid composition 90.00 90.00 95,00 95,00 acrylate copolymer emulsion "X" ^a 10.00 5.00 acrylate copolymer emulsion "Y" ^a 10.00 5.00 ^and viscosity - Brookfleld RVF, 20 RPM at 25 ° C

"X" = 0.8 to 3.0 Pa. with "Y" = 1.5 to 3.5 Pa. with

TABLE 2

Seeds treated with formulations prepared from carbofuran formulations on a solid basis

Resource,% 5 6 7 8 carbofuran 75% basis 41.40 42.70 42.70 52.10 acrylate copolymer emulsion "X" ^a 10.00 8.00 8.00 7.00 acrylate copolymer "Y"emulsion; ^and phosphoric acid 0.50 polyalkylene glycol ether 2.00 2.00 3.00 ethylene- and pro- copolymer pylene oxide 1.00 dialkylphenoxypoly (ethylene- oxyjethanol xanthan polysaccharide rubber 11, 67 ^c 0.12 0.09 potassium sorbate 0.10 0.10 dimethylsiloxane 0.01 0.01 0.01 0.01 50 ·% sulfuric acid 0.75 Rhodamine B ^d 0.40 0.40 0.40 0.40 water 35.02 46.67 46.70 36.74 active ingredient g / 1 expected 350 400 400 450 g / 1 found 360.7 397.5 397.8 451.8 viscositab (s) 20.0 30.0 23.0 35.0 agglomeration (100 mesh) tracks none none none pH 8.00 8.23 8.23 6.10 and viscosity - Brookf.ield RVF, 20 RPM at 25 ° C

"X" = · 0.8 to 3.0 Pa. with "Y" = 1.5 to 3.5 Pa. s · ь measured · in Zahn dish No. 3, ·; / ^c added as 0.6% w / w aqueous solution 'common name for dye - Color Index name - Basic Vio-let 10

Table 2 - continued

Seeds, treated with agents prepared from carbofuran compositions on a solid support

Resource,% 9 10 11 12 carbofuran 75% basis 52.10 52.10 52.10 52.10 acrylate copolymer emulsion "X" a 7.00 7.00 acrylate copolymer "Y"emulsion; ^and 7.00 7.00 phosphoric acid 1.00 polyalkylene glycol ether 3.00 3.00 3.00 2.00 ethylene- and propylene- oxide dialkylphenoxy (ethylene- oxyjethanol 1.00 xanthan polysaccharide rubber potassium sorbate diethylsiloxane 0.01 0.01 0.01 0.01 50% sulfuric acid 0.75 Rhodamine B 0.40 0.40 0.40 0.40 water 37.49 36.74 37.49 36.49 active ingredient g / 1 expected 450 450 450 450 g / 1 determined 450.9 452.1 451.7 446.3 viscositab (s) 25.0 32.0 24.0 29.5 storage (100 mesh) none none none none PH 8.57 6.02 8.55 7.50

and viscosity - Brookfield RVF, 20 RPM at 25 ° C "X" = 0.8 to 3.0 Pa. with "Y" = 1.5 to 3.5 Pa. s ^b measured in Psalm No. 3 ^and added as an 0.6% w / w aqueous solution

TABLE 3

Composition of seed treatment compositions ready for comparison (from aqueous liquid carbofuran compositions)

Resources,% AND (B) C D E F carbofuran, 400 g / l liquid composition 90.00 90.00 90.00 95,00 95,00 95,00 1 polyvinyl acetate emulsion 10.00 5.00 ethyl acrylate - polymer emulsion 10.00 5.00 vinyl acetate / acrylate multipolymer emulsion 10.00 5.00

220445

TABLE 4

Composition of the seed treatment composition ready for comparison (from solid carbofuran-based compositions)

Composition,% G H

carbofuran 75% basis 41.40 41.40 polyvinyl acetate emulsion 12.00 polyvinyl alcohol emulsion 12.00 phosphoric acid 0.50 0.50 ethylene- and pro- copolymer pylene oxide 1.00 1.00 xanthan polysaccharide rubber ll, 67 ^p U, 67 ^p dimethylsiloxane 0.01 0.01 Rhodamine B 0.40 0.40 water 33.02 33.02 active ingredient g / 1 expected 350 350 g / 1 determined 351.7 350.6 viscosity3 (s ·) 32.0 45.0 agglomeration (100 mesh) tracks tracks pH 8.11 8.15

^and measured in Psalm No. 3 ь added as 0.6% w / w aqueous solution

TABLE 5 Stability of carbofuran formulations for seed treatment i, stored at room temperature Formulation 5 6 7 after 1 month expulsion 2% tracks tracks settling none none none gelling none none none after 2 months of exclusion 8% 6% a 10% a settling none none ³ trace ⁸ gelling none none ³ moderate ⁸ after 5 months of exclusion 17% settling none gelling moderate 8 Mon. 3 months storage TABLE 6 Stability of carbofuran compositions for seed treatment, stored at 50 ° C Means 5 6 7 after 1 month expulsion 17% 16% 19% settling none none None gelling none none none after 2 months of exclusion 18% 32% a 31 ...... · establishment none none ³ none8 gelling none none ³ none3 after 5 months of exclusion 25% 17% 25% settling none none none gelling moderate moderate moderate after 8 months of exclusion 12% 14% settling none none gelling moderate strongly

* after 3 months' storage

TABLE 7 Wheat treated with carbofuran seed treatment d E Treated seeds, proportion and b C Yorkstar wheat seeds,% 97.80 97.80 97.80 97.80 97.80 resource 1,% 2.20 2,% 2.20 A,% 2.20 B,% 2.20 C,% 2.20 dust, g / 20 g seeds 0.0002 0.0005 0.0118 0.0052 0.0074

Table 7 - continued

Treated seeds, proportion F G h and and Yorkstar wheat seeds,% 97.80 97.80 97.80 97.80 97.80 3,% 2.20 4,% 2.20 D,% 2.20 E,% 2.20 F,% 0,0030 2.20 dust, g / 20 g seeds 0.0038 0.0137 0.0099 0.0123

Table 7 - continued

Treated seeds, proportion к 1 m Yorkstar wheat seeds,% 97.75 97.75 97.75 means 5,% 2.25 G,% 2.25 H,% 2.25 dust, g / 20 g seeds 0.0009 0.0104 0.0137 TABLE 8 Means treated with barley carbofuran for seed treatment Treated seeds, proportion n O P Schuler barley seeds,% 97.75 97.75 97.75 means 5,% 2.25 G,% 2.25 H, ° / o 2.25 dust, g / 20 g seeds 0.0002 0.0009 0,0098

TABLE 9

Maize treated with carbofuran seed treatment

Treated seeds, proportion G r with field corn seeds,% 95.27 95.27 95.27 means 5,% 4.73 G,% 4.73 H, ° / o 4.73 dust, g / 20 g seeds 0.0003 0,0023 0,0022

Claims (2)

1. Seed treatment agent by applying an aqueous - rosSlin seed suspension - to protect the seeds and seedlings from insects or nematodes, - characterized in that it consists of 15 to 50%>. by weight of insecticide or nematicide, 0.5 to 15% by weight of an adhesive adhesive emulsion based on 2-ethylhexyl acrylate copolymer with a solids content of 60 to 70% by weight and a viscosity of 0.5 to 4.0 Pa. s at 25 ° C, 35 to 70% by weight of water; and 10 to 30% by weight of inert components other than water, the sum of all components being 100% by weight. 2. A seed treatment composition according to claim 1, wherein the insecticide or nematicide is 2-, 3-dihydro-2,2-dimethylbenzofuran-7-ylmethylcarbamate.