GB2137498A - Fungicidal compositions based on aluminium tris-(ethyl phosphonate) - Google Patents
Fungicidal compositions based on aluminium tris-(ethyl phosphonate) Download PDFInfo
- Publication number
- GB2137498A GB2137498A GB08408138A GB8408138A GB2137498A GB 2137498 A GB2137498 A GB 2137498A GB 08408138 A GB08408138 A GB 08408138A GB 8408138 A GB8408138 A GB 8408138A GB 2137498 A GB2137498 A GB 2137498A
- Authority
- GB
- United Kingdom
- Prior art keywords
- acid
- composition according
- phosethyl
- strong base
- aqueous solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N57/00—Biocides, pest repellants or attractants, or plant growth regulators containing organic phosphorus compounds
- A01N57/10—Biocides, pest repellants or attractants, or plant growth regulators containing organic phosphorus compounds having phosphorus-to-oxygen bonds or phosphorus-to-sulfur bonds
- A01N57/12—Biocides, pest repellants or attractants, or plant growth regulators containing organic phosphorus compounds having phosphorus-to-oxygen bonds or phosphorus-to-sulfur bonds containing acyclic or cycloaliphatic radicals
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
- A01N25/22—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests containing ingredients stabilising the active ingredients
Landscapes
- Life Sciences & Earth Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Health & Medical Sciences (AREA)
- Wood Science & Technology (AREA)
- Pest Control & Pesticides (AREA)
- Plant Pathology (AREA)
- Engineering & Computer Science (AREA)
- Dentistry (AREA)
- Agronomy & Crop Science (AREA)
- Zoology (AREA)
- Environmental Sciences (AREA)
- Toxicology (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
Abstract
The fungicidal composition contains phosethyl Al (i.e. Al tris-(ethyl-phosphonate)) as the active ingredient and a salt of a weak acid and a strong base as the stabiliser. Aqueous solutions of the composition are preferably injected into the trunks of crop trees, such as avocado.
Description
SPECIFICATION
Fungicidal composition based on aluminium tris-(ethyl phosphonate)
The present invention relates to new fungicidal compositions based on a phosphorous acid ester, and to a method of combating fungal diseases of plants with the aid of these compositions.
French Patent 2,254,276 describes compositions for combating fungal diseases of plants, which contain, as the active ingredient, at least one salt of an alkyl-phosphorous acid. These compositions are effective against many phytophagous fungi, such as Phycomycetes, in particular Plasmopara viticola and various
Phytophthora. In practice, aluminium ethyl phosphite [which may also be named as "aluminium tris-(ethyl phosphonate)" and which is hereinafter identified as "phosethyl A1"] is used commercially, in the form of a wettable powder, for treatment by spraying the leaves.Although this formulation is quite effective under these conditions, in particular for protecting vines, its effectiveness takes longer to appear when it is applied curatively to tropical crops attacked, often heavily, by fungi of the Phytophthora type, such as Phytophthora cinnamomi which cause avocado rot or rot of citrus fruits.
In fact, the amounts absorbed by a foliage of low absorbency are relatively small, and are insufficient if trees which have already been attacked are treated curatively. This necessitates more applications, rendering the treatment prohibitive, slow in all respects and even inadequate in view of the severity of the attack by the fungi.
It has now been found that these diseases can be effectively combated by application, in particular by injection into the trunks of trees, of a stabilised aqueous solution of phosethyl Al. However, this poses a problem inasmuch as this active ingredient undergoes hydrolysis in an aqueous medium which substantially and progressiveiy decreases its concentration, making it impossible to obtain concentrated aqueous compositions which are stable over a period of time.
The present invention provides a process for stabilising aqueous solutions of phosethyl A1, which comprises adding a water-soluble salt of a weak acid and a strong base, as the stabiliser, to the aqueous solution of phosethyl Al. The invention also relates to aqueous solutions of phosethyl Al stabilised by this process. The term "weak acid" is to be understood as meaning a mineral acid, such as acid salts of phosphorous acid or phosphonic acid or, preferably, an organic acid, such as, e.g., an aliphatic acid, for example acetic acid, propionic acid, butyric acid, fumaric acid, oxalic acid, lactic acid or citric acid, or an aminoacid, for example ethylenediaminetetracetic acid.
Strong bases which may be used are organic bases, such as a tertiary amine, or, preferably, mineral bases, such as alkali metal hydroxides and alkaline earth metal hydroxides, preferably with a good solubility in water, such as sodium hydroxide, potassium hydroxide or lime.
The amount of stabiliser depends on the nature thereof and the concentration of phosethyl Al in the aqueous composition. In fact, if the stabiliser is present either in too small an amount or, on the other hand, in too large an amount, the solution is not clear which signifies that solubilisation of the active ingredient is insufficient, with the result that the effectiveness is correspondingly limited. Surprisingly, it has moreover been found that the most suitable amount is not that corresponding to the stoichiometric amount. For example, in the case of calcium acetate, about half the stoichiometric amount gives a stable clear solution, whilst twice this amount gives rise to a precipitate.The compositions according to the invention are preferably prepared by adding a water-soluble salt of the weak acid and the strong base, e.g. calcium acetate, to an aqueous solution of the phosethyl Al.
The aqueous composition according to the invention may also contain other water-soluble adjuvants, such as surface-active agents, although this is not necessary for injectable solutions. It may also contain certain oligo-elements which promote growth of the trees or are advantageous in combating deficiencies, such as salts of zinc, manganese, iron or boron in suitable amounts.
The phosethyl A1 is present in the compositions according to the invention in a concentration of in general between 1 and 120 g/litre and preferably between 10 and 110 g/litre.
This solution can be applied to plants to combat attacks by phytophagous fungi by any suitable treatment, such as spraying of the leaves or soaking of the roots. Excellent results have been obtained by injection into the trunk of diseased trees, such as, e.g., avocado trees, but the process can be applied to other trees, such as citrus fruit trees, or hevea or cocoa trees. The treatment is carried out by first making holes distributed around the trunk of the tree.
In a second stage, a defined amount of the aqueous phosethyl Al solution employed, which may vary from 0.1 to 5 g/m2 of soii covered by the foliage, is injected into the holes with any appropriate device, with or without using pressure.
The liquid is absorbed slowly and is preferably kept under pressure in the injection apparatus. When the injection has ended, it may be desirable to block the hole or holes with the aid of a material which is non-aggressive towards the plant tissue, such as, e.g., a wax, which may contain adjuvants, such as disinfectants, in order to reduce the risk of introducing secondary diseases. The number of treatments is very small, especially with respect to the number of interventions necessary when the leaves are sprayed. For example, on a severely attacked tree, effective curative treatment is obtained in the first year with two injections, and in the following years treatment once per year is sufficient to keep the tree healthy or on the way to recovery.The effectiveness of the treatment is remarkable, heavily attacked trees being cured within
2 years, which is surprising since other systemic fungicides which are usually active on these fungi are
ineffective when injected under the same conditions.
The examples which follow illustrate the preparation of compositions according to the invention.
Example 1
The three following compositions, where quantities are by weight, are prepared by dissolving successively
phosethyl Al and, where appropriate, calcium acetate in water:
Control Composition of
Composition the Invention
1 2
Technical grade 98% pure
phosethyl Al 102 102 102
Calcium acetate - 33 67
Water qsp 1 litre 898 865 832
The amounts of acetate added to Compositions 1 and 2 correspond respectively to half the stoichiometric
amount, for composition 1, and to all of this stoichiometric amount, for composition 2.
The three solutions are subjected to a stability test at 500C for 1 month, after which the relative degradation
of phosethyl Al and the appearance of the solution are evaluated. The results are shown in the following table:
Composition of
Evaluation criterion after Control the invention
1 month at 500C Composition 1 2
Relative degradation of
phosethyl Al 100% 12% 12%
Appearance of the solu
tion (initially clear) precipitate clear precip
itate
This table clearly shows that after 1 month at 50"C: - in the control solution, the phosethyl Al is completely degraded and a precipitate forms in the solution.
This solution is thus neither stable nor clear;
- in solutions 1 and 2 according to the invention, the degradation of phosethyl Al is limited in an acceptable manner; moreover, whilst a slight precipitate has formed in solution 2, solution 1 is clear. Thus only solution 1 is completely satisfactory.
Example 2
Two compositions are prepared by diluting composition 1, obtained in Example 1, once and, respectively, twice. Compositions containing, respectively, 51 and 20.5 grams of 98% pure phosethyl Al and 16.5 and 8.25 grams of calcium acetate are thus obtained.
Claims (17)
1. A fungicidal composition which comprises an aqueous solution of phosethyl Al containing, as the stabilising agent, a salt of a weak acid and a strong base.
2. A composition according to claim 1 in the form of a clear aqueous solution.
3. A composition according to claim 1 or 2 wherein the weak acid is an organic acid.
4. A composition according to 1 or 2 wherein the weak acid is an aliphatic acid or an aminoacid.
5. A composition according to claim 1 or 2 wherein the weak acid is acetic acid, propionic acid, butyric acid, furmaric acid, oxalic acid, lactic acid, citric acid or ethylenediaminetetracetic acid.
6. A composition according to any one of claims 1 to 5 wherein the strong base is calcium hydroxide.
7. A composition according to any one of claims 1 to 5 wherein the strong base is sodium hydroxide or potassium hydroxide.
8. A composition according to any one of claims 1 to 5 wherein the stabiliser is calcium acetate.
9. A composition according to claim 1 in the form of a clear aqueous solution which comprises an aqueous solution of phosethyl Al containing, as stabiliser, half the stoichiometric amount of calcium acetate.
10. A composition according to any one of claims 1 to 9, which contains from 1 to 120 g/litre of phosethyl
Al.
11. A composition according to claim 1 substantially as hereinbefore described with especial reference to
Example 1 or 2.
12. A process for obtaining stable aqueous solutions containing phosethyl Al according to any one of claims 1 to 11, which comprises adding a water-soluble salt of a weak acid and strong base to these solutions.
13. A process according to claim 12 substantially as hereinbefore described with especial reference to
Example 1.
14. A method for combating attacks by phytophagous fungi on crop plants which comprises applying to the plants an effective amount of composition according to any one of claims 1 to 11.
15. A method for combating attacks by phytophagous fungi on crop trees which comprises injecting an effective amount of composition according to any one of claims 1 to 11 into the trunk of the tree.
16. A method according to claim 15 wherein the crop tree is avocado.
17. A method according to claim 15 substantially as hereinbefore described.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8305562A FR2543405B1 (en) | 1983-03-31 | 1983-03-31 | FUNGICIDAL COMPOSITION BASED ON ALUMINUM TRIS ETHYL PHOSPHONATE |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8408138D0 GB8408138D0 (en) | 1984-05-10 |
| GB2137498A true GB2137498A (en) | 1984-10-10 |
| GB2137498B GB2137498B (en) | 1986-07-09 |
Family
ID=9287542
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08408138A Expired GB2137498B (en) | 1983-03-31 | 1984-03-29 | Fungicidal compositions based on aluminium tris-(ethyl phosphonate) |
Country Status (22)
| Country | Link |
|---|---|
| JP (1) | JPS59184112A (en) |
| AU (1) | AU562117B2 (en) |
| BE (1) | BE899299A (en) |
| BR (1) | BR8401472A (en) |
| CH (1) | CH660282A5 (en) |
| DE (1) | DE3410011A1 (en) |
| ES (1) | ES531128A0 (en) |
| FR (1) | FR2543405B1 (en) |
| GB (1) | GB2137498B (en) |
| GR (1) | GR79874B (en) |
| HK (1) | HK25790A (en) |
| HU (1) | HU194707B (en) |
| IL (1) | IL71368A (en) |
| IT (1) | IT1179361B (en) |
| KE (1) | KE3891A (en) |
| LU (1) | LU85279A1 (en) |
| MA (1) | MA20074A1 (en) |
| NL (1) | NL8400974A (en) |
| OA (1) | OA07694A (en) |
| PT (1) | PT78349B (en) |
| SG (1) | SG37389G (en) |
| ZA (1) | ZA842365B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2163652A (en) * | 1984-08-29 | 1986-03-05 | Rhone Poulenc Agrochimie | Fungicidal composition based on aluminium tris-(ethyl-phosphonate) |
| US4935410A (en) * | 1983-03-31 | 1990-06-19 | Rhone-Poulenc Agrochimie S.A. | Fungicidal aluminum tris-alkyl-phosphonate composition |
| GB2304708A (en) * | 1995-09-05 | 1997-03-26 | Rhone Poulenc Agrochimie | Improving the fruit yields from banana plants |
| WO1999004630A1 (en) * | 1997-07-21 | 1999-02-04 | Rhone-Poulenc Agro | Agrochemical composition |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0617288B2 (en) * | 1986-05-07 | 1994-03-09 | クミアイ化学工業株式会社 | Agro-horticultural wettable powder composition |
| JP2840847B2 (en) * | 1989-01-23 | 1998-12-24 | ローヌ・プーランアグロ株式会社 | Stabilized pesticide composition |
| DE4142974C2 (en) * | 1991-12-24 | 1996-05-30 | Alexander Burkhart Gross Und E | Fungicidal compositions |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2000031A (en) * | 1977-06-17 | 1979-01-04 | Shell Int Research | Stabilization of Oxime Carbamates |
| EP0038778A2 (en) * | 1980-04-21 | 1981-10-28 | Ciba-Geigy Ag | Alkyl phosphonites, process for their preparation and the use of alkyl phosphonites as fungicides |
| EP0066759A1 (en) * | 1981-05-21 | 1982-12-15 | Union Carbide Corporation | Dialdehyde containing compositions |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2112136A6 (en) * | 1970-11-06 | 1972-06-16 | Dynachim Sarl | Pesticidal organophosphorus compositions - stabilized with aminoacid salts |
| FR2254276B1 (en) * | 1973-12-14 | 1977-03-04 | Philagro Sa | |
| FR2377155A1 (en) * | 1977-01-14 | 1978-08-11 | Philagro Sa | FUNGICIDE COMPOSITIONS BASED ON ALCOYLPHOSPHITES |
| US4382091A (en) * | 1981-04-30 | 1983-05-03 | Syntex (U.S.A.) Inc. | Stabilization of 1-substituted imidazole derivatives in talc |
-
1983
- 1983-03-31 FR FR8305562A patent/FR2543405B1/en not_active Expired
-
1984
- 1984-03-19 DE DE19843410011 patent/DE3410011A1/en active Granted
- 1984-03-27 IL IL71368A patent/IL71368A/en unknown
- 1984-03-28 NL NL8400974A patent/NL8400974A/en not_active Application Discontinuation
- 1984-03-28 GR GR74240A patent/GR79874B/el unknown
- 1984-03-28 JP JP59060523A patent/JPS59184112A/en active Granted
- 1984-03-29 MA MA20296A patent/MA20074A1/en unknown
- 1984-03-29 GB GB08408138A patent/GB2137498B/en not_active Expired
- 1984-03-29 ZA ZA842365A patent/ZA842365B/en unknown
- 1984-03-29 IT IT47965/84A patent/IT1179361B/en active
- 1984-03-29 AU AU26239/84A patent/AU562117B2/en not_active Ceased
- 1984-03-30 PT PT78349A patent/PT78349B/en not_active IP Right Cessation
- 1984-03-30 HU HU841289A patent/HU194707B/en not_active IP Right Cessation
- 1984-03-30 LU LU85279A patent/LU85279A1/en unknown
- 1984-03-30 CH CH1632/84A patent/CH660282A5/en not_active IP Right Cessation
- 1984-03-30 ES ES531128A patent/ES531128A0/en active Granted
- 1984-03-30 OA OA58269A patent/OA07694A/en unknown
- 1984-03-30 BE BE0/212672A patent/BE899299A/en not_active IP Right Cessation
- 1984-03-30 BR BR8401472A patent/BR8401472A/en not_active IP Right Cessation
-
1989
- 1989-06-14 SG SG373/89A patent/SG37389G/en unknown
- 1989-06-21 KE KE3891A patent/KE3891A/en unknown
-
1990
- 1990-04-04 HK HK257/90A patent/HK25790A/en unknown
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2000031A (en) * | 1977-06-17 | 1979-01-04 | Shell Int Research | Stabilization of Oxime Carbamates |
| EP0038778A2 (en) * | 1980-04-21 | 1981-10-28 | Ciba-Geigy Ag | Alkyl phosphonites, process for their preparation and the use of alkyl phosphonites as fungicides |
| EP0066759A1 (en) * | 1981-05-21 | 1982-12-15 | Union Carbide Corporation | Dialdehyde containing compositions |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4935410A (en) * | 1983-03-31 | 1990-06-19 | Rhone-Poulenc Agrochimie S.A. | Fungicidal aluminum tris-alkyl-phosphonate composition |
| US5070083A (en) * | 1983-03-31 | 1991-12-03 | Rhone Poulenc Agrochimie, S.A. | Fungicidal aluminum tris-alkyl-phosphonate composition |
| GB2163652A (en) * | 1984-08-29 | 1986-03-05 | Rhone Poulenc Agrochimie | Fungicidal composition based on aluminium tris-(ethyl-phosphonate) |
| AU571995B2 (en) * | 1984-08-29 | 1988-04-28 | Rhone-Poulenc Agrochimie | Fungicidal composition based on aluminium tris (ethyl phosphonate) |
| GB2304708A (en) * | 1995-09-05 | 1997-03-26 | Rhone Poulenc Agrochimie | Improving the fruit yields from banana plants |
| GB2304708B (en) * | 1995-09-05 | 1999-03-17 | Rhone Poulenc Agrochimie | Method for improving fruit yields from banana plants |
| WO1999004630A1 (en) * | 1997-07-21 | 1999-02-04 | Rhone-Poulenc Agro | Agrochemical composition |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3410011A1 (en) | 1984-10-04 |
| GB8408138D0 (en) | 1984-05-10 |
| ZA842365B (en) | 1984-12-24 |
| GB2137498B (en) | 1986-07-09 |
| AU2623984A (en) | 1984-10-04 |
| IL71368A (en) | 1987-09-16 |
| IT8447965A1 (en) | 1985-09-29 |
| MA20074A1 (en) | 1984-10-01 |
| NL8400974A (en) | 1984-10-16 |
| BE899299A (en) | 1984-10-01 |
| KE3891A (en) | 1989-09-01 |
| FR2543405B1 (en) | 1986-01-03 |
| BR8401472A (en) | 1984-11-06 |
| CH660282A5 (en) | 1987-04-15 |
| JPS59184112A (en) | 1984-10-19 |
| HU194707B (en) | 1988-03-28 |
| IL71368A0 (en) | 1984-06-29 |
| FR2543405A1 (en) | 1984-10-05 |
| SG37389G (en) | 1989-10-13 |
| JPH0573721B2 (en) | 1993-10-15 |
| ES8504434A1 (en) | 1985-04-16 |
| HK25790A (en) | 1990-04-12 |
| PT78349A (en) | 1984-04-01 |
| IT1179361B (en) | 1987-09-16 |
| IT8447965A0 (en) | 1984-03-29 |
| AU562117B2 (en) | 1987-05-28 |
| OA07694A (en) | 1985-05-23 |
| GR79874B (en) | 1984-10-31 |
| HUT36685A (en) | 1985-10-28 |
| LU85279A1 (en) | 1985-10-14 |
| PT78349B (en) | 1986-07-22 |
| DE3410011C2 (en) | 1993-01-28 |
| ES531128A0 (en) | 1985-04-16 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19930329 |