LOW VOLATILE POLYAMINE SALTS OF ANIONIC PESTICIDES

Abstract

The present invention relates to a salt comprising an anionic pesticide (A) and a cationic polyamine of the formula (B) as described in the description. The invention further relates to an agrochemical composition comprising said salt. It also relates to a method for preparing said salt comprising combining the pesticide in its neutral form or as salt, and the polyamine in its neutral form or as salt. In addition, the invention relates to a method of combating harmful insects and/or phytopathogenic fungi. It also relates to a method of controlling undesired vegetation. Finally, the invention relates to seed comprising said salt.

Claims

1. A salt comprising an anionic pesticide comprising a carboxylic acid group, and a cationic polyamine of the formula (B) ##STR00007## wherein R.sup.1, R.sup.2 are each independently H or C.sub.1-C.sub.6 alkyl, n is between 5 to 40.

2. The salt according to claim 1, wherein the anionic pesticide is a herbicide selected from the group consisting of aromatic acid herbicides, phenoxycarboxylic acid herbicides, and organophosphorus herbicides comprising a carboxylic acid group.

3. The salt according to claim 2, wherein the anionic pesticide is a herbicide selected from the group consisting of dicamba, glyphosate, glufosinate, L-glufosinate, 2,4-D, aminopyralid, aminocyclopyrachlor, MCPA, and a mixture thereof.

4. The salt according to claim 3, wherein the anionic pesticide is dicamba, 2,4-D, or MCPA.

5. The salt according to claim 3, wherein the anionic pesticide is dicamba, glyphosate, or a mixture thereof.

6. The salt according to claim 3, wherein the anionic pesticide is dicamba.

7. The salt according to claim 1, wherein R.sup.1 and R.sup.2 are each independently H or methyl, n is from 9 to 22.

8. The salt according to 1, wherein R.sup.1 is methyl and R.sup.2 is H, n is from 9 to 22.

9. An agrochemical composition comprising at least one salt according to claim 1.

10. An agrochemical composition, comprising: 1) 10-70 wt. % of at least one salt according to claim 1, 2) 30-90 wt. % water, 3) optionally at least one further pesticide, and 4) optionally up to 10 wt. % auxiliaries, wherein the amount of all components adds up to 100 wt. %.

11. A method for preparing the salt according to claim 1 comprising combining the pesticide in its neutral form or as salt, and the polyamine in its neutral form or as salt.

12. The method according to claim 11, wherein the pesticide and the polyamine are combined in water.

13. A method of combating harmful insects and/or phytopathogenic fungi, which comprises contacting plants, seed, soil or habitat of plants in or on which the harmful insects and/or phytopathogenic fungi are growing or may grow, plants, seed or soil to be protected from attack or infestation by said harmful insects and/or phytopathogenic fungi with an effective amount of the salt according to claim 7.

14. A method of controlling undesired vegetation, which comprises allowing an herbicidal effective amount of the agrochemical formulation according to claim 9 to act on plants, their habitat or on seed of said plants.

15. A seed comprising the salt according to claim 1.

Description

EXAMPLES

[0165] Dicamba acid: A technical quality of the herbicide comprising 90 wt. % dicamba free acid. Oliqo-N,N-Bis(3-aminopropyl)methylamine (MPPI): formula as below, wherein n is 9-22.

##STR00006##

[0166] Example 1-Preparation of Salts

[0167] Salts were prepared comprising dicamba as pesticide anion and various polyamine cations. A known quantity of dicamba acid was suspended in water while stirring. The suspension was titrated with polyamine to a pH of 7.0 to 8.0 until all solids were dissolved and the salts have formed. Additional water was added to adjust the desired concentration of dicamba (600 g/l). Table 1 lists the details of the final compositions. The dicamba concentration was 48.4 wt. % in each case. The water concentration added up to 100 wt. % in each case. The quality of the polyamine is given in parenthesis. N,N-Bis(3-aminopropyl)methylamine (100%) refers to BAPMA hereinafter and Oligo-N,N-Bis(3-aminopropyl)methylamine (100%) refers to MPPI hereinafter. It was demonstrated, that all tested salts have a very good solubility in water, i.e. that dicamba salts are soluble up to at least 600 g/I.

TABLE-US-00001 TABLE 1 Dicamba salts Concentration Entry Type of polyamine cation (w/w %) 1 N,N-Bis(3-aminopropyl) 12.5 methylamine (100%) 2 Oligo-N,N-Bis(3-aminopropyl) 18.4 methylamine (100%) Entry 1 is not part of this invention.

[0168] Example 2-Volatility of Dicamba Determined in Open Petri Dish

[0169] A dicamba sample of the aqueous solutions of dicamba (600 g/l) as prepared in Example 1 (Table 1) was diluted with distilled water in a ratio of 1:50. To help spreading of the samples uni-formly on the surface of the plate, Silwet L-77 was added (0.1 wt. %). A total of 300 μl of this diluted sample was applied per Petri dish (diameter 5 cm). The dishes were kept at an environment chamber (Barnstead Environ-Cab Lab-line 680A) with forced air flow (air vent out) up to one month at 50° C. and 30% humidity. Afterwards the plates were extracted with acetic acid/methanol and the pesticide quantified by HPLC (Columbus C18 column) to determine the volatile loss of dicamba acid. Thus, it was demonstrated, that the salt of dicamba in the present invention had a reduced volatility compared to commercial dicamba salt formulations.

TABLE-US-00002 TABLE 2 Petri dish volatility of Dicamba salts Type of Volatility Volatility polyamine after 2 weeks after 4 weeks Entry cation (wt % loss) (wt % loss) 1 BAPMA 7.17 9.83 2 MPPI 1.33 3.83 Entry 1 is not part of this invention.

[0170] Example 3-Secondary Loss of Dicamba with Quantitative Humidome Study

[0171] A quantitative humidome study provides a measurement of relative secondary loss in a dynam-ic, contained environment via air sampling and quantitative analysis (an indication of potential volatile or particulate loss from a treated substrate; usually measured as the amount of dicamba captured in an air sampling filter per air volume or ng/m.sup.3).

[0172] The method of a quantitative humidome study utilized a treated substrate (e.g. glass, soil, potting mix or plants) placed in a plastic tray covered with a clear plastic humidome (overall size 25 cm wide×50 cm long×20 cm tall; source: Hummert) fitted with an air sampling filter cassette (fiberglass and cotton pad filter media; source: SKC) connected to a vacuum pump (flow rate: 2 L/min). Individual humidomes representing different study treatments and replicates were placed in a controlled growth chamber environment (typical temperature at 35° C. and 25 to 40% Relative Humidity).

[0173] After 24 hours, filters were collected, extracted and analyzed for dicamba content using GC-MS. The total amount of dicamba captured was then divided by total volume of the air flow through the filter to calculate total dicamba (ng), average dicamba concentration ng/m.sup.3 and % relative loss or improvement compared to a standard treatment. Lower loss of dicamba indicates a better or improved secondary loss profile for a given treatment.

[0174] Table 3 details a quantitative humidome study conducted in a growth chamber to compare secondary loss profiles of selected dicamba candidates. All treatments included 0.25% v/v non-ionic surfactant Induce from Helena Chemical and the substrate media was 8 glass petri plates with total area 594 cm.sup.2. Aqueous solutions of the candidates were prepared by dissolving the components as indicated in Table 3 in water at room temperature while stirring. The samples were clear solutions. They remained clear solutions after storage for at least four weeks at room temperature.

TABLE-US-00003 TABLE 3 secondary loss of dicamba with quantitative humidome study Type % reduction of poly- Dicamba Polyamine in secondary amine Rate rate loss relative to cation (g ae/ha) (g ae/ha) Dicamba-BAPMA BAPMA 560 148 — MPPI 560 231 76 MPPI 560 213 64

[0175] According to the results in Table 3, the formulations of the present invention provided a significant reduction in potential dicamba secondary loss relative to the dicamba-BAPMA reference.

[0176] Example 4-Secondary Loss of Dicamba with Bioassay Humidome Study

[0177] A bioassay humidome study provides a measurement of secondary loss in a static, contained environment using sensitive soybean plants as a biological indicator (an indication of potential volatile or particulate loss from a treated substrate; usually measured as a visual 0-100 percent assessment of soybean injury where more injury indicates higher potential loss (exposure)).

[0178] The method of a bioassay humidome study utilized a treated substrate (e.g. glass, soil, potting mix or plants) placed in a plastic tray covered with a clear plastic humidome (overall size 25 cm wide×50 cm long×20 cm tall; source: Hummert) along with 2 dicamba sensitive soybean plants (1-2 true leaves). Individual humidome representing different study treatments and replicates were placed in a greenhouse environment (with a typical diurnal temperature range of 25 to 40° C. and 75 to 98% Relative Humidity).

[0179] After 18 to 24 hours, the sensitive soybean plants were removed from the humidomes and placed on a greenhouse bench for observation and visual response or injury assessment over 2-3 weeks period. The level of injury to soybean plants is an indirect measurement of amount of dicamba exposure from treated substrate. Lower injury to plants indicates a relatively better or improved secondary loss treatment profile.

[0180] Table 4 details a bioassay humidome study conducted in a greenhouse to compare secondary loss profiles of selected dicamba candidates. All treatments included 0.25% v/v non-ionic surfactant Induce from Helena Chemical and the substrate media was 2 glass plates with total area 620 cm.sup.2. Aqueous solutions of the candidates were prepared by dissolving the components as indicated in Table 4 in water at room temperature while stirring. The samples were clear solutions. They remained clear solutions after storage for at least four weeks at room temperature.

TABLE-US-00004 TABLE 4 secondary loss of dicamba with bioassay humidome study Type % reduction of poly- Dicamba Polyamine in secondary amine Rate rate loss relative to cation (g ae/ha) (g ae/ha) Dicamba-BAPMA BAPMA 1120 296 — MPPI 1120 462 41 MPPI 1120 426 45

[0181] According to the results in Table 4, the experimental formulations provided a significant reduction in soybean injury related to dicamba secondary loss relative to the dicamba-BAPMA reference.