NZ574159A

NZ574159A - An improved herbicide composition

Info

Publication number: NZ574159A
Application number: NZ574159A
Authority: NZ
Inventors: David Wallis
Original assignee: Schaik S Biogro Pty Ltd Van; Biotech Science Pty Ltd
Priority date: 2006-06-15
Filing date: 2007-06-15
Publication date: 2010-07-30
Also published as: AU2007260589B2; AU2007260589A1; EP2034823A4; WO2007143791A1; EP2034823A1

Abstract

Disclosed is a herbicidal composition, said composition including a glyphosate salt, fulvic acid and a surfactant blend, said surfactant blend including the following components: (a) sodium lauryl ether sulphate; (b) a C10-C18 alcohol (such as lauryl alcohol); (0) a water miscible organic solvent (such as diethylene glycol monobutyl ether or isopropanol) capable of dissolving component (b); (d) one or more solubilizing agents (such as sodium xylene sulphonate and/or ethanol); (e) polysiloxane; and (f) water.

Description

New Zealand Paient Spedficaiion for Paient Number 574159 574159 AN IMPROVED HERBICIDE COMPOSITION FIELD OF THE INVENTION This invention relates to an improved herbicidal composition which contains glyphosate, also known as N-phosphonomethylglycine (HOOCCH.sub.2 5 NHCH.sub2 PO(OH).sub.2).

More particularly this invention relates to a glyphosate salt based herbicide composition which has increased efficacy over existing formulations utilising the same level or lower of the active ingredient of the glyphosate salt and a herbicidal composition based on glyphosate salts that have a faster penetration 10 rate into the foliage to which the herbicidal activity of the glyphosate salt is required to activate than has previously been available.

BACKGROUND ART Glyphosate herbicides are already well known in the relevant technological field associated with herbicide formulations, and presently there are a variety of 16 commercia products available of glyphosate salts forming the active ingredients of a range of herbicides, for example Round Up®, Accord® and Round Up Xtra of the Monsanto company. Another well known commercial formulation is also known as Touch Down®.

Each of these commercial formulations offer a herbicide which contain a 20 glyphosate salt, which when applied to plants releases or otherwise provides glyphosate ions. It is these ions that create the herbicidai activity which disrupts the physiological behaviour of the plant which is being killed or controlled by the herbicide.

To a large extent, though there is some dispute from certain environmental 25 groups, glyphosate herbicides are considered to be fairly environmentally friendly, and are generally applied in an aqueous solution or dispersion, most commonly by spraying onto the foliage of the plants to be killed or controlled. 574159 2 As the person skilled in the art would be aware, though herbicides are generally classified as a weed controller or killer, the fact is that herbicides can also be frequently used for killing or controlling plants not normally thought of as weeds, and hence this should be kept in mind when determining the scope of this ■ 5 invention as the herbicide can be easily applied to other plant species which are not usually considered generally as weeds, but for one reason or another require to be controlled or eliminated normally to provide for a new cleared land for the incorporation of a new crop species or the like.

Generally, herbicides that have the glyphosate sold as the active ingredient are 10 mixed together with one or more surfactants which assist in retention of droplets of the applied spray on the foliage of the treated plants.

Previous pjblished material, on the surfactants with the active ingredient glyphosate salt has concluded that the use of a surfactant is critical with any glyphosate spray mixture, as rt assists in the adhesion and spread of the spray 15 droplets to the foliage surface and penetration of the water soluble pesticide through the hydrophobic cuticle that covers the foliage surface, as well as potentially providing other enhancing herbicidal activities of the glyphosate.

Nonetheless the more surfactant you put into the formulation the less glyphosate salt can be applied. Hence, there needs to be a balance between 20 the amount of active Ingredient and the surfactant which is responsible for applying the herbicide on to the plant which extermination and control is required.

If there is too much surfactant in an attempt to improve the dispersion and the adhesion of the spray droplets containing the active ingredient glyphosate to the 25 plant, this could mean that ultimately the composition will not remain as a pure suspension, and ingredients including the surfactant itself will begin to drop out.

As the person skilled in the art will appreciate the problem becomes even more acute in situations where the glyphosate herbicide is mixed by an end user in a large drum or container, to which contents would then be sprayed on to the 30 foliage to be treated. 574159 WO 2007/143791 PCT/AU2007/000835 In these situations it is vital that the composition and the contents dissolved and supported therein remain in suspension, any separation of the composition will mean that what is being sprayed on to the foliage will not provide for an appropriate balance between the active ingredient glyphosate and the 5 surfactant.

Should the surfactant begin to drop from suspension or be reduced in quantity so as to add high levels of glyphosate in an attempt to improve the killing or controlling effect of the herbicide, basically means that the amount of wetting of the droplets when sprayed on to the foliage will be significantly reduced, and 10 therefore the penetration into the foliage will be minimal and the uptake of the glyphosate ions to physiologically interact with the plant will be restricted.

Therefore, it begins to be realised that at present in the relevant field of glyphosate herbicides, that there are problems associated with the relativity between the essential ingredients, that being the glyphosate salt and the 15 surfactant.

Still further, the glyphosate salt is an expensive ingredient and therefore the amount used is proportional normally to the cost of the product. At present using traditional combinations of the active ingredient glyphosate salt with surfactant means that if we are to improve the kill time or control of destroying 20 the foliage higher proportions of the active ingredient glyphosate needs to be included into the composition.

Nonetheless, a consequence of increasing the quantity of glyphosate salts into the herbicide and then treating the foliage, is that the active ingredient remains on the surlace potentially for a greater period of time, particularly if the amount 25 of surfactant present in the composition needed to be reduced in order to accommodate this extra addition of the active glyphosate salt to improve the kill effect.

A problem with such an arrangement is that if the active ingredient remains on the leaf for a longer period of time, it is more susceptible to removal from the leaf if exposed to conditions such as rain and the like. 574159 PCT/AU 2007/000835 4 As to be expected if the glyphosate salt is applied to the plant and is yet to release its glyphosate ions into the foliage, inclement weather will simply wash the active ingredient from the foliage onto the ground.

Such a situation is quite troublesome, as it means that the end user will again 5 have to treat the foliage, bringing extra costs to the killing and controlling of the weed, either by the use of further product and/or additional time and resources required in again spraying the final composition onto the foliage to be treated.

Therefore, as the above presents there still remains a need in the field of herbicidal compositions to provide a glyphosate based herbicide which can 10 have greater efficacy without the need of simply increasing concentration of the active ingredient glyphosate salt.

Still further, there still remains a need for a herbicidal composition which not only has improved efficacy using existing or lower levels of glyphosate active ingredient, but also can more rapidly penetrate the foliage of the plant to be 15 killed, thereby leaving exposed for a far lesser time on the surface of the foliage to be removed by inclement weather or the like.

OBJECTS OF THE INVENTION Accordingly, an object of this invention is to provide for a glyphosate salt based herbicide which has increased efficacy over existing formulations utilising the 20 same level or lower of the active ingredient of the glyphosate salt compared to those previously available.

A further object of this invention is to provide for a herbicidal composition based on glyphosate salts that have a faster penetration rate into the foliage to which the herbicidal activity of the glyphosate salt is required to activate.

Further objects and advantages of the invention will become apparent from a complete reading of this document.

SUMMARY OF THE INVENTION 574159 Accordingly, in one form of the invention there is provided a herbicidal composition, said composition including a glyphosate salt, fulvic acid and a surfactant blend, said surfactant blend including the following components (a) to (e)' (a) a salt of a sulphated alkoxylated alcohol; (b) a C10-C18 alcohol; (c) a water miscible organic solvent capable of dissolving component (b); (d) one or more solubilizing agents; and (e) water.

Preferably the salt of sulphated alkoxylated alcohol is sodium lauryl ether sulphate.

Preferably the C10-C18 alcohol is lauryl alcohol.

In preference the water in the surfactant blend contains a chelating and/or 15 sequestering agent In preference the solubilising agent is sodium xylene sulphonate and/or ethanol.

Preferably the alcohol portion of component (a) is lauryl alcohol.

In preference the herbicidal composition further includes a plant nutrient.

An advantage of such a herbicidal composition is that as the surfactant of the 20 defined ingredients is used in combination with the glyphosate salt active ingredienl of the herbicide, the effectiveness of the active ingredient is substantially improved.

Still further, the use of the fulvic acid improves the metabolic rate of the plants biological- systems, of which this speeding up activity of the plant means that the 25 glyphosate ions are able to be absorbed into the plant at a much faster rate. 574159 6 A further advantage of such an arrangement is that as the glyphosate salt is combined with a particularly defined and determined surfactant, there is far greater improvement in the dispersion and wetting of the composition when the droplets are sprayed onto the foliage of the treated plants.

Advantageously, as the droplets are extremely well separated into some of the smallest dimensions possible in order to obtain their individual identify, the spraying droplets by being of improved minute dimensions are able to wet and penetrate the foliage surface at a much faster rate.

Hence, advantageously the surfactant by improving the wetting action means 10 that rather than having the active ingredient tied up in globules of large droplets sitting on the surface of the foliage to be treated, they are dispersed outwards which then allows the pesticide through the hydrophobic cuticle that covers the foliar surface to more quickly penetrate the plant to bring about the kill.

Advantageously, this improved dispersion and wetting action of the herbicidal 15 compositions through the combination of the surfactant and the active ingredient salt means that killing time of a plant being treated can be reduced to hours compared to previously available herbicide compositions, such as the well known commercial brands referred to previously, such as Round Up which takes initia' effect within 3 to 5 days.

As introduced above this increase in an efficacy by allowing improved access of the active ingredient by virtue of the surfactant dispersing the product at a far higher level, is again improved upon by the further edition of the fulvic acid such that the intake of the herbicide is increased because the biological activity of the plant has been increased by this addition.

It is well known in the art that the nutritional function of the fulvic acid is bdth direct and immediate. Fulvic acid substances tend to chelate various nutrients and metals in the soil, thus preventing the precipitation of the metals in the forms of oxide, hydroxides or carbonates, which then become unstable because they are in soluble forms that cannot be absorbed by the root hairs of the plant. 574159 WO 2007/143791 PCT/AU2007/000835 7 Advantageously, the use of the fulvic acid is increasing the nutritional functions of the plant being controlled, thereby allowing it to grow faster Regrettably for the plant being treated with the herbicidal composition of the invention, this is a disadvantage because the faster growth rates transpires to faster intake of the & herbicide thus the faster rate of killing said plant.

Advantageously, with the faster growth rate of the plant, the improved wetting dispersion of the active ingredient onto the surface of the plant by virtue of the surfactant mixture means that the product can be sprayed onto the foliage even if rain is expected shortly. An advantage of this invention as introduced above 10 by virtue of the synergestic interaction between the glyphosate salt, surfactant and fulvic asid means that the formulation becomes rain fast on the foliage within minutes compared to 2 to 4 hours that one would expect from well known commercial formulations of herbicides'such as Round-Up®.

Advantageously, as efficacy of the overall herbicidal composition of this 15 invention can be improved without the need of simply increasing the quantity of the glyphosate in the product, means that cost savings can be made, and there is no problems associated with reducing the amount of surfactant in the product, which as to be expected if such undertakings were completed, the ability of the surfactant to wet the surface will be substantially reduced.

Alternatively, if efficacy using traditional methods was to increase one way was to in fact increase the surfactant level, but this could only be done at expense reducing the glyphosate salt levels, and such an approach in any event was limited because in time the surfactant itself would begin to drop from suspension of which the problems associated with such an action were referred 25 to above.

A further advantage is that as the glyphosate salt is not left active on the surface of the foliage being killed for a prolonged period of time there is a lower risk in having any of the salt ending up in the ground, to which certain •envjronmer-tal people still argue have some consequences if introduced into the 30 soil. 574159 8 Advantageously, with this invention the result provides benefits to the soil as potentially an enhancement rather than any type of degradation. The addition of the fulvic acid into the soil will automatically increase the bicactivity of the soil, and hence we are enhancing the biological nutritional functionality of the 5 soil rather than producing any risk or the like through the application of this herbicidal composition.

An advantage of having the surfactant including a C10 - C18 alcohol, is that such alcohols such as lauryl alcohol, means that with the evaporation of the other ingrecients the lauryl alcohol can remain with the molecular coating on the 10 foliage which almost protects it from water or the like.

Hence, the water can literally bead or bounce off the foliage rather than washing away the applied herbicidal composition.

A further advantage of such an arrangement, is that the surfactant defined to work in synergy with the active glyphosate salt and fulvic acid in providing the 15 herbicidal composition is all naturally derived and very rapidly biodegradable by ultra violet light.

Still further, the formulation is substantially non drift, particularly if used with air induction nozzles and does not require additional adjunctives commonly used by the well recognised commercial formulations of glyphosate salt herbicides 20 such as Round-Up® to ensure against drift.

Still further, the herbicidal composition defined above assists in trapping the fine odour causing particles which advantageously has benefits for occupational, health and safety issues associated with such herbicidal compositions.

In preference, the glyphosate salt is isopropylamine, diammoniun or 25 trimethylsolfonium or a combination thereof, and/or esters and/or derivatives of said salts and combinations thereof.

In preference, there is between 8 to 60% of the surfactant blend making up 2 to 20% solid weight of the herbicidal composition. 574159 9 i Preferably, there is between 0.08% to 0.46% solids of fulvic acid in the herbicidal composition.

In preference the fulvic acid is in combination with chelated nutrients including potassium, phosphorus, nitrogen or a combination thereof.

In preference the plant nutrient is ammonium sulphate.

In preference there is between 0.26 to 0.33% solids of ammonium sulphate in the herbicidal composition.

Advantageously the ammonium sulphate provides a nutrient intake for the plant under herbicidal attack, increasing the plants metabolism which then also 10 increases the intake rate of the herbicidal compostion.

In preference the herbal composition further includes triethanolamrne.

In preference there is between 0.4% to 4% of trrethanolamine in the herbicidal composition.

In preference the herbal composition further includes polysiioxane.

In preference the polysiioxane is between .4% to 2% of a polyether modified polysiioxane in the herbicidal composition.

Advantageously the polysiioxane provides surfactant synergy with the surfactant blend defined by components (a) to (e), and wherein the triethanolamine adjusts the final pH of the composition to around 7,0 for the 20 effective operating conditions for the polysiioxane.

Preferably the sodium iaurly ether sulphate contains between 1 and 5 moles of an alkoxy gJoup.

Preferably, the alkoxy group is ethoxy. 574159 Preferably, sodium laurly ether sulphate contains 2 or 3 moles of ethylene oxicle.

Preferably component (b) is lauryl alcohol, cetyl alcohol, steryl alcohol, or a combination thereof. s Preferably component (c) is an ether or a C1-C4 branched or unbranched alcohol, or a mixture thereof.

Preferably the solvent (o) is Methylene glycol mpnobuty! ether or isopropanol. DETAILED DESCRIPTION OF THE INVENTION To further cescribed this invention a preferred herbicidal composition is listed 10 here under examples 1 and 2. Nonetheless these examples are provided for illustrative purposes only and it is to be recognised that many of the components included and the quantities detailed are not essential to the general working of the invention- SURFACTANT BLEND to be used with Example 1 and Example 2 Herbicidal 15 Compositions BLEND TO 1000 LITRES Sodium Lauryl Ether Sulphate (3LES 70% Active) 533Kg Lauryl Alcohol 17Kg Di Glycol Monobutyl Ether 53.3Kg Ethyl Alcohol 180Litres EDTA Di-Sodium Salt 1.7Kg Sodium Xylene Sulphonate 50.6Kg Water 167Litres 49% Solids Formulation 574159 11 EXAMPLE! TO 1000 Litres Soft Water (pH adjusted to 6.5 with citric acid) 474 gms/litre glyphosate IPA salt Fulvic Acid (11.5% solids) Ammonium Sulphate Solution (at SSgms/Litre) Surfactant Blend 10 (at 30% solids) T.E.A 85% Polyether Modified Polysiioxane 860Litres .1kg 2QLitres 4QLitres SOLitres 4kg 4 Litres Adjust final pH to 7,0 with TEA 85% EXAMPLE 2 TO 1000 Litres 474 gms/litre glyphosate IPA salt Fulvic Add (11.5% solids) Ammonium Sulphate Solution (at l55gms/Litre) Surfactant Blend (at 30% solids) 231.5kg 115Litres SOLitres 565Litres

Claims

WO 2007/143791 574159 PCT/AU2007/000835 12 T.E.A 85% 20kg Polyether Modified Polysiioxane 20Litres Adjust final pH to 7.0 with TEA 85% 574159 13 CLAIMS:

1. A herbicidal composition, said composition including a glyphosate salt, fulvic acid and a surfactant blend, said surfactant blend including the following components: 5 (a) sodium lauryl ether sulphate; (b) a C10-C18 alcohol; (c) a water miscible organic solvent capable of dissolving component (b); (d) one or more solubilizing agents; 10 (e) polysiioxane; and (f) water.

2. The herbicidal composition of claim 1 wherein the C10-C18 alcohol is lauryl alcohol.

3. The herbicidal composition of any one of claims 1 or 2 wherein the 15 water in the surfactant blend contains a chelating and/or sequestering agent.

4. The herbicidal composition of any one of the preceding claims wherein the solubilizing agent is sodium xylene sulphonate and/or ethanol.

5. The herbicidal composition of any one of the preceding claims wherein the alcohol portion of component (a) is lauryl alcohol. 20

6. The herbicidal composition of any one of the preceding claims further including a plant nutrient.

7. The herbicidal combination of any one of the preceding claims wherein there is between 8 to 60% of the surfactant blend making up 2 to 20% solid weight of the herbicidal composition. 25

8. The herbicidal composition of any one of the preceding claims wherein there is between 0.08% to 0.46% solids of fulvic acid in the herbicidal composition. 574159 14

9. The herbicidal composition of any one of claims 5 to 8 wherein the plant nutrient is ammonium sulphate.

10. The herbicidal composition of claim 9 wherein there is between 0.26% to 0.6% solids of ammonium sulphate in the herbicidal composition. 5

11. The herbicidal composition of any one of the preceding claims further including triethanolamine.

12. The herbicidal composition of claim 11 wherein there is between 0.4% to 4% of triethanolamine in the herbicidal composition.

13. The herbicidal composition of any one of the preceding claims wherein 10 the polysiioxane is between 0.4% to 5% of a polyether modified polysiioxane in the herbicidal composition.

14. The herbicidal composition of any one of the preceding claims wherein the sodium lauryl ether sulphate contains between 1 and 5 moles of an alkoxy group.

15 15. The herbicidal composition of claim 15 wherein the alkoxy group is ethoxy.

16. The herbicidal composition of any one of the preceding claims wherein the fulvic acid is in combination with chelated nutrients including potassium, phosphorus, nitrogen or a combination thereof.