GB2043448A

GB2043448A - Insecticide adjuvant system

Info

Publication number: GB2043448A
Application number: GB8005244A
Authority: GB
Original assignee: Sandoz AG
Current assignee: Sandoz AG
Priority date: 1979-02-20
Filing date: 1980-02-15
Publication date: 1980-10-08
Also published as: IL59402A0; FR2449401A1; BR8000965A; IT8047936A0; DE3005016A1; PL222102A1; NL8000952A; DK58880A; BE881737A; ZA80977B; AU5564780A; JPS55113701A; KR830001608A

Abstract

The invention provides an insecticide adjuvant system for use in conjunction with or incorporating an insecticide, said adjuvant system comprising certain combinations of natural sugars and/or molasses, mineral carriers and/or inorganic pigments and surfactants. The invention further provides a method of combating insects in a locus with the aid of the adjuvant in conjunction with an insecticide.

Description

SPECIFICATION Insecticide adjuvant system The present invention relates to an insecticide adjuvant system appropriate in particular for stomach poison and/or light degradable insecticides such as microbial, e.g. virus or bacterial, insecticides.

The object of the present invention is to provide a practical commercial form of an insecticide having optimal biological properties. This is a very complex problem, in particular when a stomach poison type insecticide and/or a light degradable insecticide, especially a virus insecticide is used.

Adjuvants may be generally defined as constituting a system of one or more materials which in association with the active ingredient provide a beneficial result. Adjuvants therefore may be viewed as materials that form either an integral part of an insecticide formulation or may be made and sold separately for use in conjunction with an insecticide formulation.

The insecticide should be capable of being applied by practical means which, at the present time, involves largely spray applications.

The adjuvant systems should therefore have good wettability and storage stability, be capable of passing through fine spray nozzle orifices and of remaining at the site of application, such as the leaf of a plant, despite rain and other adverse ambient conditions.

In addition, an adjuvant for an unstable insecticide, e.g. a virus insecticide, must provide protection or additional protection for the insecticide against conditions which depreciate the potency thereof, particularly heat and light.

As stomach poison type insecticides act essentially as stomach poison, they must be ingested by the insect or insect larva. The adjuvant system must not be inedible or otherwise offensive to the insect or larvae but should rather have a baiting property that attracts the insect or larvae and encourages eating of the adjuvant and consequently the ingestion of the stomach poison type insecticide.

Moreover, the adjuvant system must not affect the biological properties of the insecticide adversely but should rather increase its effectiveness.

Hitherto developed adjuvant systems, whilst enhancing the biological efficacy of such insecticides have tended not to fully satisfy the requirements of ease of manufacture of the adjuvant system, of storage stability, of ease of preparation of the spray forms and of problem-free sprayability of such spray preparations.

The present invention is based on the finding that certain combinations of natural sugars and/or molasses, mineral carriers and/or inorganic pigments and surfactants provide the basis for an insecticide adjuvant system meeting the requirements to a very satisfactory extent.

More specifically, the present invention provides a water dispersible insecticide adjuvant system which system comprises 30 to 90 parts by weight of natural sugars and/or molasses, 5 to 60 parts by weight of mineral carriers and/or inorganic pigments and 1 to 1 2 parts by weigh of a surfactant.

The water dispersible adjuvant system according to the invention may be in solid or liquid form.

A preferred and advantageous embodiment of the present invention is in solid particulate free-flowing wettable powder form.

The solid water dispersible adjuvant system comprises preferably 40 to 85 parts of natural sugars and/or molasses (the sugars most preferably being present in an amount of 70 to 85 parts and the molasses in an amount of 40 to 50 parts) 10 to 30 parts of mineral carriers and/or inorganic pigments, and 2 to 6 parts of surfactant.

The water dispersible liquid adjuvant system comprises preferably 20 to 70 parts, more preferably 25 to 40 parts of water, preferably 30 to 65 parts, more preferably 35 to 45 parts of natural sugars and/or molasses, preferably 5 to 55 parts, more preferably 10 to 25 parts of mineral carriers and/or inorganic pigments, and preferably 2 to 6 parts surfactant.

The term sugar is employed herein in a broad sense to include any of the sweet C6 ,2 carbohydrates or mono or disaccharides capable of being processed into fine powdered form, e.g. sucrose, maltose, dextrose, lactose, levulose and mixtures thereof, including invert sugars. The preferred sugars are the disaccharides, particularly sucrose.

By the term molasses is meant the uncrystallised sirup that is obtained as a by-product of sugar manufacture.

The term mineral carrier is employed herein to include any silica, Diatomaceous earth, or natural silicate, in particular clay material, processable into a finely powdered form. Examples of useful clay material are Kaolin clays, Olancho clays, Attapulgite clays and Bentonite clays. Attapulgite clays are preferably used when wettable powders are formulated.

The term inorganic pigments is employed herein to include in particular white pigments such as titanium dioxide, zinc oxide, calcium sulphate, aluminium oxide etc. The preferred inorganic pigment is titanium dioxide.

For suspension concentrates, preferably Kaolin clays and/or titanium dioxide are used.

The term surfactant is employed herein in a broad sense to include the usual wetting and dispersing agents, and comprises anionic and nonionic types, the main purpose thereof being to permit easy water dispersibility of the adjuvant composition as well as compatibility of the adjuvant system with the insecticide in the spray liquor. The preferred surfactants are lignin sulphonates (dispersing agent), sodium lauryl sulphate (wetting agent), phosphoric acid esters of ethoxylated alkyl phenols, phosphoric acid esters of ethoxylated fatty alcohols and ethoxylated sorbitan fatty acid esters or mixtures thereof.

The solid or liquid adjuvant systems of the invention may contain further additives, e.g.

buffering agents such as an alkali metal dihydrogen phosphate e.g. KH2PO4 or NaH2PO4, antifoam, preserving agents and/or stabilizers.

In addition, the solid adjuvant system may contain up to 50%, preferably 30 to 40%, by weight of vegetable flour.

The vegetable flour may be any flour of vegetable origin including any finely divided material obtained from vegetable seeds. Such flour may be derived from the whole or only the germ portion of the seeds and may be defatted or non-defatted. In general, however, except for cereal flours, it is preferred that the flour be defatted, i.e. the vegetable oil therein is removed. The preferred flours include soya bean powder, wheat flour, cotton seed powder and cornmeal (maize) powder. Particularly preferred is defatted cornmeal powder.

Any insecticide, in particular stomach poison and/or light degradable insecticide, may be used in conjunction or be formulated with the adjuvant systems of the invention.

The adjuvants are, however, particularly preferably employed in conjunction with microbial insecticides, for example the bacterial insecticide Bacillus Thuringiensis or virus insecticides reported for a variety of insects including the cotton bollworm, the tobacco budworm, the cabbage looper, the fall armyworm, the beetarmyworm, the alfalfa caterpillar and the like.Inclusion bodies with occluded virions, and the production and use of virus insecticides containing them, are described, inter alia, in Steinhaus and Thompson, Preliminary Field Tests Using a Polyhedrosis Virus to Control the Alfalfa Caterpillar, Journal of Economic Entomology, Vol. 42, No. 2, pp. 301-305 (April 1949); Ignoffo, Production and Virulence of a Nuclear-Polyhedrosis Virus from Larvae of Trichopulsia ni (Hubner) Reared on a Semi-synthetic Diet, Journal of Insect Pathology, 6 pp. 318-326 (1964); Ignoffo, The Nuclear-Polyhedrosis Virus of Heliothis zea (Boddie) and Heliothis virescens (Fabricius), Journal of Invertebrate Pathology, 7, No. 2, pp. 209-216 and 217-226 (June, 1965); Ignoffo, Possibilities of Mass-Producing Insect Pathogens, Internat.

Colloq. Insect Pathol. Netherlands, pp.

91-117 (1967); Ignoffo, Virus Living Insecticides, Current Topics in Microbiology and Immunology, Vol., 42, pp. 129-167 (1968); and U.S. Patent 3,639,578. The peferred virus insecticide is Heliothis zea NPV(Nuclear Polyhedrosis Virus).

As will be appreciated, in relation to microbial insecticides, in general the microbial pathogens are not in practice isolated from the mediums in which they are processed. However, the microbial insecticide employed is preferably reasonably concentrated especially in relation to water content such that no more than 80%, more preferably no more than 25% by weight thereof comprises water. In general, in connection with microbial insecticides such as virus insecticides, it is desirable that no more than 8%, more preferably no more than 3% by weight of water is introduced into the composition when incorporating the insecticide.

The adjuvants of the invention are obtained in conventional manner.

The liquid adjuvant system provided by the invention may, for example, be prepared by mixing the surfactant with the mineral carriers and/or inorganic pigments in a blender. This mixture is added to a solution of natural sugars and/or molasses in water containing optionally a buffer, preserving agents, stabilisers and/or antifoam. The resulting dispersion is milled and homogenised, e.g. by passing through a pearl mill.

For the preparation of the solid adjuvant system, the surfactant, mineral carriers and/or inorganic pigments, the natural sugar and optional vegetable flour may be mixed in a blender, then milled, e.g. in a hammer mill, and blended once more.

If molasses is used, this is preferably absorbed to a suitable carrier, e.g. silica, most preferably in a weight proportion molasses: carrier of approximately 1:1, e.g. from 1:0.8 to 1:1.2, then a surfactant is added eventually together with another mineral carrier, e.g. clay and/or an inorganic pigment and, if desired, a vegetable flour and/or formulating agents.

The mixture is milled, e.g. using a hammer mill, and blended once again.

The solid constituents employed in the adjuvant systems defined above are finely divided, desirably pass through a 200 Tyler Standard Mesh Screen and preferably have a particle size of from 0.1 to 20 microns.

The method of combating insects and protecting plants employing the adjuvant of the invention is conjunction with an insecticide also forms part of the present invention. The preferred method employs Heliothis NPVas insecticide for combating Heliothis insects in the treatment of cotton, tomato, tobacco, soya bean or sorghum cultures.

In application, thel liquid adjuvant system is suitably applied to a rate of 1/4 to 5 litre per hectare, preferably 1/2 to 2-1 /2 litre per hectare. The solid adjuvant system is suitably applied at a rate of from 1/4 to 6 kilogram per hectare, preferably 1/2 to 3 kilogram per hectare. The insecticide is employed at the normal rate, the amount of insecticide being preferably chosen so that, on application at the above-mentioned adjuvant application rates, the insecticide is applied at an effective insecticidal rate.

In general, they are applied in a weight ratio insecticide:adjuvant in the range of 1:1 to 1:1500, preferably of 1:3 to 1:20 when synthetic insecticides and of 1:30 to 1:1 500 when microbial insecticides are involved.

The adjuvants may be applied in conjunction with an insecticide in a manner known peruse, e.g. by mixing them with an insecticide as a tank mix, or incorporated in an insecticidal composition.

Insecticidal compositions comprising an insecticide in association with an adjuvant of the invention also form part of the present invention. Such compositions may include additional adjuvants. They may be formulated in any conventional form or in the form of a twin packet.

The amount of insecticide employed in insecticide compositions based on the adjuvant systems of the invention will naturally vary depending on the insecticide employed. However, in general, it is preferred that the composition comprise 0.1 to 50%, more preferably 0.2 to 20% by weight of insecticide.

When microbial insecticides are used, the compositions preferably comprise 0.1 to 20%, more preferably 0.1 to 10% by weight of insecticide.

Insecticide compositions incorporating the adjuvant systems defined above may be employed in manner known per se, e.g. by dispersion in water in the tank of a spray applicator and spraying the resulting suspension onto the locus to be protected. The degree of water dilution may vary depending inter alia on the insecticide and the applicator employed. When incorporating a microbial insecticide for example, the application form may include from 50 to 99.9%, more preferably 90 to 99.8% by weight of water.

The baiting properties, the protection against photo-irradiation, the wettability, the storage stability, the dispersibility and the homogenous character of the dispersions of the insecticide adjuvant system may be determined by standard test methods.

In the following examples which illustrate the present invention parts are by weight unless otherwise noted. In the example ATTA CLAY is a trademark designation for a commercially available Attapulgite clay.

EXAMPLE 1: Preparation of a solid adjuvant 1.5 Parts of sodium lauryl sulphate, 2.5 parts of lignin sulphonate (Polyfon 0), 2.0 parts of potassium dihydrogen phosphate and 12.0 parts of Attaclay (attapulgus clay) rue mixed in a ribbon blender for approximately 1 hour, then passed through a hammer mill and mixed in a blender for a further hour. To 1 8 parts of this premixture are added in a blender 82 parts of crystalline sucrose, the particle size of which is mainly between 100 and 250 micron (which favours an easy spray preparation due to quick wetting and dissolving of the sugar).

EXAMPLE 2: Solid adjuvant with pigment 1.5 Parts of sodium lauryl sulphate, 2.5 parts of Polyfon 0, 2.0 parts of potassium dihydrogen phosphate, 10.0 parts of titanium dioxide and 12.0 parts of Attaclay are mixed in a ribbon blender for 1 hour, then passed through a mill (e.g. Bauermeister or hammer mill) and mixed in a blender for a further hour. To 28 parts of this pemixture are added in a blender 72 parts of crystalline sucrose, the particle size of which is mainly between 100 and 250 micron.

EXAMPLE 3: Liquid adjuvant A finely divided mixture of 1.5 parts of sodium lauryl sulphate, 2.5 parts off Polyfon 0, 10.0 parts of Kaolin (fine grade), 15.0 parts of titanium dioxide and 1.0 part of ammonium caseinate is prepared (premixture A).

In a stirring vessel a solution is prepared by dissolving in 29.79 parts of water 0.01 part off Biopolymere XB 23 (a high molecular weight xanthan gum), 0.1 part sorbic acid, 0.1 part of potassium sorbate, 1.0 part of potassium dihydrogen phosphate, 38.8 parts of molasses and 0.2 parts of Antifoam Emulsion B (premixture B). 30 Parts of premixture A are stirred into 70 parts of premixture B, and the whole is passed through a pearl mill to make a homogeneous and stable suspension concentrate.

EXAMPLE 4: Adjuvant/lnsecticide Composition 1 900 g of a technical concentrate of Heliothis nuclear polyhedrosis virus (containing 14.2 X 109 polyhedral inclusion bodies per gram), 1000 ml of water and 1 g of Polysorbate 80 (commercially available polyoxyethylene (20) sorbitan mono-oleate; The Merck Index 9th Ed., p. 985, reference number 7360) are well mixed and homogenized (premixture A; slurry) 5000 g of titanium dioxide, 10.000 g sucrose, 500 g sodium lauryl sulphate, 500 g of lignin sulphonate, 6000 g of silica and 500 g of KH2PO4 are mixed and milled to a fine powder (premixture B).

Premixture A is uniformly sprayed onto premixture B. Then 25.6 kg of fine sucrose (about 50 to 1 50 mesh) is added and the whole mixed for 1 hour.

The resulting wettable powder has good physical properties and a biological potency of 0.54 X 109 polyhedral inclusion bodies per gram.

Claims

1. A water dispersible insecticide adjuvant system which system comprises 30 to 90 parts by weight of natural sugars and/or molasses, 5 to 60 parts by weight of mineral carriers and/or inorganic pigments, and 1 to 1 2 parts by weight surfactant.

2. An adjuvant according to Claim 1 in solid form.

3. An adjuvant according to Claim 2 in particulate free-flowing wettable powder form.

4. An adjuvant according to Claim 3 comprising 40 to 85 parts by weight of natural sugars and/or molasses, 10 to 30 parts by weight of mineral carriers and/or inorganic pigments and 2 to 6 parts by weight of surfactant.

5. An adjuvant according to Claim 4 comprising 70 to 85 parts by weight of natural sugars.

6. An adjuvant according to Claim 4 comprising 40 to 50 parts by weight of molasses.

7. An adjuvant according to Claim 6 wherein the molasses is absorbed to a carrier in a weight proportion molasses:carrier of from 1:0.8 to 1:1.2.

8. An adjuvant according to Claim 1 in liquid form.

9. An adjuvant according to Claim 8 comprising 20 to 70 parts by weight of water, 30 to 65 parts by weight of natural sugars and/or molasses, 5 to 55 parts by weight of mineral carriers and/or inorganic pigments and 2 to 6 parts by weight of surfactant.

10. An adjuvant according to Claim 9 comprising 25 to 40 parts by weight of water, 35 to 45 of natural sugars and/or molasses and 10 to 25 parts by weight of mineral carriers and/or inorganic pigments.

11. An adjuvant according to any one of Claims 1 to 10, wherein the inorganic pigment is a white pigment.

12. An adjuvant according to Claim 11, wherein the white pigment is titanium dioxide.

13. An adjuvant according to any one of Claims 1 to 12, wherein the mineral carrier is a finely divided clay material.

14. An adjuvant according to Claim 13 as appendent to any one of Claims 1 to 7, wherein the clay material is an Attapulgite clay.

1 5. An adjuvant according to Claim 1 3 as appendent to any one of Claims 8 to 12, wherein the clay material is a Kaolin clay.

1 6. An adjuvant according to any one of Claims 1 to 15, wherein the surfactant comprises a lignin sulphonate, sodium lauryl sulphate, a phosphoric acid ester of an ethoxylated fatty alcohol, an ethoxylated sorbitan fatty acid ester, or mixtures thereof.

1 7. An adjuvant according to Claim 16, wherein the surfactant comprises a lignin sulphonate as dispersing agent and sodium lauryl sulphate as wetting agent.

18. An adjuvant according to any one of Claims 1 to 1 7 comprising a buffering agent.

1 9. An adjuvant according to Claim 18, wherein the buffering agent is KH2PO4 or NaH2PO4

20. An adjuvant according to any one of Claims 1 to 1 9 substantially as hereinbefore described.

21. An insecticidal composition comprising an adjuvant as defined in any one of Claims 1 to 20 in association with an insecticide.

22. A composition according to Claim 21 comprising from 0.1 to 50% by weight of insecticide.

23. A composition according to Claim 22 comprising from 0.1 to 20% by weight of insecticide.

24. A composition according to Claim 23, wherein the insecticide is a stomach poison and/or light degradable insecticide.

25. A composition according to Claim 24, wherein the light degradable insecticide is a microbial insecticide.

26. A composition according to Claim 25, wherein the microbial insecticide is a bacterial insecticide or a virus insecticide.

27. A composition according to Claim 26, wherein the bacterial insecticide is Bacillus Thurigiensis.

28. A composition according to Claim 26, wherein the virus insecticide is a Nuclear Polyhedrosis Virus of Heliothis zea, Heliothis virescens or Trichopulsia ni.

29. A composition according to Claims 21 to 28 in application form including from 50 to 99.9% by weight of water.

30. A composition according to Claim 29 including from 90 to 99.8% by weight of water.

31. A method of combating insects in a locus which comprises spraying onto the locus an aqueous dispersion of an adjuvant system claimed in any one of Claims 1 to 20 in conjunction with an insecticide.

32. A method according to Claim 31, in which a liquid adjuvant as defined in any one of Claims 8 to 20 is applied at a rate of i to 5 litre per hectare.

33. A method according to Claim 32, in which the liquid adjuvant is applied at a rate of + to 2+ litre per hectare.

34. A method according to Claim 31, in which a solid adjuvant as defined in any one of Claims 1 to 7 and 11 to 20 as appendent to Claims 1 to 7 is applied at a rate of i to 6 kilogram per hectare.

35. A method according to Claim 34, in which the adjuvant is applied at a rate of + to 3 kilogram per hectare.

36. A method according to any one of Claims 31 to 35, wherein the insecticide is a Heliothis virus insecticide and the insects are Heliothis insects.

37. A method according to any one of Claims 31 to 36 in which an aqueous disper sion of an insecticidal composition as defined in any one of Claims 21 to 28 is applied.

38. A method according to Claim 36 or 37, wherein the plants to be protected are selected from the group consisting of cotton, tomatoes, tobacco, soya beans or sorghum cultures.

39. A method according to Claim 38, wherein the plants are cotton.

40. A composition according to any one of Claims 21 to 30 substantially as hereinbefore described.

41. A method according to any one of Claims 31 to 39 substantially as hereinbefore described.