ENGINEERING IMPROVED CHEMICAL PERFORMANCE IN PLANTS

Abstract: The effect of certain agricultural chemicals, viz. fungicides, herbicides, insecticides, nematicides and plant-growth regulators, is improved by co-administration of them with one or more additives which modify the uptake of the chemical by modifying physico-chemical properties of the leaf or which alter the physical relationship between the agricultural chemical and the leaf surface such that the uptake of the agricultural chemical is altered beneficially including by holding the agricultural chemical in a layer on the leaf surface during a period when it is not needed by the plant (as during the winter months) and then releasing it as a result of increased temperature and/ or light degradation in the spring. The invention provides compositions containing one or more of the said agricultural chemicals and one or more of the said additives, and methods of improving the harvest of a given crop by applying it to one or more of the said agricultural chemicals and one or more of the said additives simultaneously or within up to about 15 days of one another. The compositions may be made up with purgatives e.g. phenolpthalein, or emetics such as apomorphine and ipecahuana although the additives themselves have the ability to reduce the mammalian toxicity of agricultural chemicals with which they are mixed.

Description: ENGINEERING IMPROVED CHEMICAL PERFORMANCE IN PLANTS Modification of Chemical Uptake This invention relates to agricultural chemicals, which term is used herein to mean fungicides, herbicides, insecticides, nematicides and plant growth regulators, and to methods of using them and compositions containing them. The present invention is concerned with altering the performance of such chemicals. Conventional approach to this involves altering the chemical structure to a greater or lesser degree without altering the class or basic chemical type to which the compound belongs, and/or altering the physico-chemical properties of the formulation containing the chemical, e.g. by the addition of chemicals to stick the agricultural chemical to the target organism or to improve.the rainfastness of the agricultural chemical. The literature (including patents) is full of examples of how the conventional approach may be carried I out, in particular it is known that addition of a wetting agent (surfactant/surface active agent) can enhance the effect of many agricultural chemicals when it is used at rates which lower the surface tension of the spray solution and enable it to spread over leaf surfaces (particularly where these are waxy) with better effectiveness. This invention is based on the discovery that the efficiency of agricultural chemicals can be markedly improved by the use of wetting agents/surfactants at levels far higher than are required- to reduce surface tension as hereinbefore described. At high levels (see Appendix I) such compounds may physically modify the structure of the outer walls of plant cells and leaf surfaces and hence physically modify the " structure of a plant leaf such that an agricultural chemical may penetrate it better. Suitable 5 surfactants (wetting agents) include but are not limited to those defined in Appendix I (page 10). Where this is done then it has been found beneficial to make a further addition of a coating agent as hereinafter defined in Appendix II (page 12). Alternatively such a coating agent may be used beneficially without a surfactant 10 (wetting agent). This invention provides an agricultural formulation comprising an agricultural chemical as hereinbefore described together with a wetting agent (surfactant) and/or a coating agent as hereinafter described. Such formulations may be in concentrate form, needing 15 addition of, for example, water to make them ready for use. This invention also provides a method of applying an agricultural chemical to a target plant, in which a surfactant (wetting agent) and/or coating agent as hereinafter described is also applied either simultaneously with the agricultural chemical or not more 20 than fifteen days (preferably 10 days) before or after. When the application is simultaneous, the agricultural chemical and the surfactant (wetting agent) and/or coating agent may be supplied in a single formulation or may be mixed in situ in a spray or other chemical-applying apparatus. - . . r - - 25 The wetting agents (surfactants) and/or coating agents used in the formulations and methods of the present invention include but are not limited to those listed in Appendix I wetting agents (surfactants) and Appendix II (coating agents). Such chemicals for use in combination with an agricultural chemical are herein referred 30 to as "Additives". The use of compositions in accordance with the present invention can enhance the effectiveness of chlormequat (B-chloroethyl trimethylammonium chloride or CCC). They may also be beneficially used with other plant growth regulators including auxins, 35. gibberellins, ethephon and with mixtures of these. The use of high OMPI IPO level of surfactants (wetting agents) and/or coating agents as described in this invention, have a very general property on the uptake of' agricultural chemicals- by plant leaves, such that the activity of a wide range of agricultural chemicals may be beneficially enhanced. In the case of surfactants (wetting agents) by a greater amount than would be expected from their use as a method of reducing surface tension alone especially at temperatures below 10 C. A further aspect of this invention is the use of the substances acting as surfactants• (wetting agents) forming this invention to produce a further enhancement of activity when used in conjunction with a coating agent as described in Appendix II. The coating agents used in the formulation and methods of the present invention include, but are not limited to, those polymeric coating agents listed with examples in Appendix II (page 12). Two or more such coating agents in the same or different classes may be used together. Although it is beneficial for a surfactant (wetting agent) to be used with a coating agent as described in Appendix II of this invention, such coating agents may be used alone to hold an agricultural chemical onto the leaf of a crop plant during a period when there is no growth and/or necessity for the chemical. An example of such a period would be during the months of December and January in the U.K. where there is little plant growth and fungal diseases are not developing * - Thus a growth regulator as hereinbefore described and/or a fungicide may be applied in combination with a coating agent as defined hereinafter in Appendix II or the said coating agent may be applied to the plant within fifteen days of the application of the agricultural chemical. On the return of Spring when the plant may beneficially use a growth regulator and/or the action of a fungicide against fungal disease becomes of importance, then with increasing air temperatures and/or increasing solar radiation, the coating agent breaks down to free the trapped agricultural chemical. At this point in the utilisation of the agricultural chemical by the crop the presence of the surfactant (wetting agent) contained also within the coating is especially beneficial. -£ T EA OMPI Additives as defined in Appendix I (page 10) and Appendix II (page 12)- can act as purgative- agents and thus reduce the mammalia toxicity of an agricultural chemical with which they are formulate or with which a formulation containing these additives are mixed in the spray tank or before adding to the spray tank. This decrease in mammalian toxicity may be further enhanced by the addition of known purgatives and/or emetics including phenolphthal castor oil, ipecachuana and apomorphine. Although within the patent literature there are reports of encapsulated agricultural chemicals that slowly release their contents, the use of a coating agent to preserve an agricultural chemical in position during what is effectively a dormant period and its subsequent release with the return of growing conditions, is a novel and hitherto unexpected feature of such coating process The following experimental data show effects produced by certain compositions and methods in accordance with the present invention and compare such effects with those of the prior art. gmtEΛ OMPI Examples of Additives % Concentration in final spray solution applied to plants imple No. (1) Alkyl phenol ethylene oxide condensate 0.75 (v/v) (2) Alkyl phenol ethylene oxide condensate 2.5 (v/v) (3) Lissapol 1.0 (v/v) (4) Na lauryl sulphate 0.5 (w/v) (5) Ethomeen 1.5 (v/v) (6) Di - 1 - p - menthene 0.3 (v/v) (7) Di - 1 - p - menthene 1.0 (v/v) (8) D - 1 - p - menthene 2.0 (v/v) (9) Epikote 825 5.0 (v/v) (10) Methyl Cellulose 2.5 (v/v) (11) Poly vinyl acetate 1.5 (v/v) Concentrations are expressed as a % in the final spray solution applied to the plants. -gU EΛ - OMPI _ Additives are defined as in the numbered examples on page 5. EXPERIMENT 1- (Spring Application) This is a comparison of a standard commercially available formulation of Chloremequat viz Mandops chlormequat 46 (contains 460 g Chlorocholine chloride per litre) to which has been added surfactant (wetting agent) viz 250 ml of alkyl phenol ethylene condensate per 1000 litres of spray solution), with Mandops Chlormequat 46 to which the additives as in: (a) Example 1 (b) Example 6 (c) Example 1 -f Example 6 have been added, with respect to their ability to shorten the stems of wheat. Stem Height °l- Reduction cm Control (untreated) 94.3 Chlormequat 46 84.0 10.9 (a) Chlormequat 46 + Additives as in Example 1 81.6 13.5 (b) Chlormequat 46 + Additives as in Example 6 79.8 15.4 (c) Chlormequat 46 + Additives as in Example 1 + Example. ,6- • 77.4 17.9 The application rate is equivalent to 1.6 kg per hectare of ' chlorocholine chloride applied in 225 litres of water to Maris Huntsman wheat in March (during the late tillering stage). Result are expressed as an average of 250 measurements. EXPERIMENT 2 (Autumn Application) This is a comparison of a standard commercially available chlormequat (Mandops Chlormequat 46) to which has .been added surfactant (wetting agent) viz 250 ml of alkyl phenol ethylene oxide condensate in 1000 litres of spray; with Mandops Chlormequat to which the additives as in: - REX O PI IPO (a) Example 1 (b) Example 6 (c) Example-1 + Example 6 have been added, with respect to their ability to shorten the stems of wheat. Stem Height % Reduction (cm) Control (untreated) 95.1 Chlormequat 46 94.4 0.7 (a) Chlormequat 46 + Additives as in Example 1 91.2 4.1 (b) Chlormequat 46 + Additives as in Example 6 90.6 4.7 (c) Chlormequat 46 + Additives as in Example 1 + Example 6 88.9 6.5 The application rate was 1.6 kg per hectare of chlorocholine chloride applied in 225 litres of water per hectare to Maris Huntsman wheat in late November (during the early tillering period). Results are expressed as an average of 250 measurements. EXPERIMENT 3 (Barley) This is a comparison of a " standard commercially available formulation of chlormequat viz Mandops Chlormequat 46 to which has been added surfactant (wetting agent) viz (250 ml of alkyl phenol ethylene oxide condensate per 1000 litres of spray solution); with Mandops Chlormequat 46 to which the additives as in: (a) Example 1 (b) Example 6 (c) Example 1 + Example 6 have been added, with respect to their ability to strengthen the stems of barley plants . 7. Increase in Breaking Strain Control (untreated) " Chlormequat 46 6.8 (a) Chlormequat 46 + Additives as in Example 1 15.5 (b) Chlormequat 46 + Additives as in Example 6 13.9 (c) Chlormequat 46 + Additives as in Example 1 + Example 6 18.4 Application was made in May to Mazurka spring barley at the late tillering stage. The application rate was 1.6 kg Chloro¬ choline chloride per hectare applied in 225 litres of water. The stem strength was measured by applying a force through a spring balance to the mid point of the first inter-node until breakage occurred. Results expressed as an average of 250 measurements. EXPERIMENT 4 (Paraquat) A standard commercially available formulation of paraquat viz Gramoxone to which has been added additional surfactant (wetting agent) viz 500 ml of alkyl phenol ethylene condensate per 1000 litres of spray solution was compared with Gramoxone to which additives in: (a) Example 2 * -. . * - (b) Example 7 (c) Example 2 + Example 7 have been added, with respect to their abilities to destroy an old sward. Score 7 days after application: 0 = nil effect 10 = 1007. kill Score Gramoxone 6 Gramoxone + Additives as in Example 2 7 Gramoxone + Additives as in Example 7 7.5 Gramoxone- + Additives as in Example 2 + Example 7 9 O PI The application rate was 1.1 kg paraquat per hectare in 400 litres of water. EXPERIMENT 5 (Glyphosate) A standard commercially available formulation of glyphosate viz Roundup to which has been added additional surfactant (wetting agent) viz 250 ml of alkyl phenol ethylene oxide condensate per 100 litres of spray solution was, compared with Roundup to which additives as in: (a) Example 2 (b) Example 7 (c) Example 2 + Example 7 had been added, with respect to their ability to kill a mixed weed population (grasses and broad leaf weeds) two weeks after spraying. Score; 0 = nill effect Score Roundup 7 Roundup + Additives as in Example 2 8 Roundup + Additives as in Example 7 8 Roundup + Additives as in Example 2 + Example 7 9 The application rate is ^ quivalent to 0.5 kg of glyphosate per hectare applied in 225 litres of water . OMPI APPENDIX I Suitable surfactants (surface active agents) or wetting agents, include but are not limited to: 1 Condensation products of ethylene oxide.with fatty alcohols such as oleyl alcohol and cetyl alcohol, with alkyl phenols such as octylphenol, nonylphenol and octylcresol. Partial esters derived from long chain fatty acids and hexitol anhydrides. The condensation products of the said partial esters (2) with ethylene oxide. Lecithins. Sodium or calcium salts of polyacrylic acids and lignin sulphonic acids. Fatty acid esters of glycerol, sorbitan, sucrose or pentaerythr condensates of these with ethylene oxide and/or propylene oxid Quaternary salts and condensates of ethylene oxide with amines. Substances sold under the Trade Marks: • Ethomeen Ethodu ' omeen Duoquod Arquad Lissapol Citowett Agral Substances sold under the trivial chemical names: . Sodium lauryl sulphate Alkyl phenol ethylene oxide condensate Sodium dodecylbenzene sulphonate Such surfactants are normally employed on crops not possessing waxy surface (e.g. cereals) in the final spray solution applied to the plants .at. from 0..01 - 0.025 (w/w for solids, w/v for liquids). On plants possessing a waxy surface e.g. Brussels sprouts up to 0.05% concentration of surfactant is used. Such solutions have been considered to give the maximum benefit in farm use. In this invention the final concentration in the applied spray solution is from 0.075 (w/v) in solids 0.0757. v/v in liquids) on all plants to 5% w/v (solids) or 57. v/v (liquids). APPENDIX II Suitable coating agents include but are not limited to the following: 1 Di-1-p-menthene (a terpene sold under the trade names of Miller Gard, Vapor Gard and Miller Aide. 2 Acrylic polymers and copoly ers e.g; Plyacrylic acid Polyacrylamide Poly aer lonitrile Polymethyl methacry Poly (Ethylacrylate Butylacrylate) Cellulose Ethers e.g: Hydroxethyl cellulo Sodium carboxymethy cellulose 4 Cellulose Esters e.g: Methyl cellulose 5 Epoxy ' Resins e.g: Epikote 828, Epikote 1001 6 Hydrocarbon Resins e.g: Petroleum Resins 7 Polyester Resins Polyether Resins 8 Poly amide Resins 9 Rubbers e.g: Natural Rubber Polyurethane Butyl Rubber Nitrile Rubber Pol chloroprene Rubber/oil Emuline 10 Silicone Resins and polymers " R OM 11 Styrene Polymers and Copolymers e.g: Polystyrene Styrene/Butadiene copolymer 12 Thermosetting Polymers e.g: Melamine formaldehyde copolymer Phenol-formaldehyde resins Urea-formaldehyde resins 13 Vinyl Polymers and Copolymers e.g: Polyvinyl Acetate Polyvinyl Alcohol Polyvinyl Butyral Polyvinyl Pyrrolidone Poly (Vinylacetate- Vinyl chloride) Poly (Vinylacetate- Acrylate) 14 Natural drying oils e.g: Linseed Linseed/Tung These coating agents are applied in from 2 - 10 gallons of water per acre using aerial application or controlled droplet application and from 10 - 500 gallons per acre using conventional ground spray equipment. -. .. The application rate is from 100 ml - 25 litres of the coating agent per sprayed acre of crop. O PI

Claims: CLAIMS 1 A method of applying an agricultural chemical that is a fungicide, herbicide, insecticide, nematicide or plant-growth regulator, characterised in that an additive or additives in the form of a surfactant (wetting agent) sufficient to modify the physico-chemical structure of a plant surface and/or a coating agent is also applied to the same locus as the agricultural chemical not more than fifteen days earlier than or more than fifteen days later than the agricultural chemical, whereby the desired effect of the agricultural chemical is enhanced especially at temperatures below 10 C. 2 A method as claimed in claim 1 in which the surfactant (wetting agent) is as defined " -iιj ^Appendix I and the coating agent is as defined in Appendix II. 3 A method as claimed in claim 1 in which the coating agent is di-1-g-methene. 4 A method as claimed in claim 2 in which the agricultural chemical is chlorocholine (CCC) and it is applied to wheat, oats or rye to improve the yield of the crop by shortening and/or strengthening the stem to control lodging and/or effecting beneficially the development of the grain bearing ear. 5 A method as claimed in claim 2 in which the agricultural chemical is chlorocholine chloride (CCC) and it is applied to barley, maize, millet, sorghum or rice to improve the yield of the crop by shortening and/or strengthening the stem to control lodging and/or effecting beneficially the development of the grain bearing ear. 6 A method as claimed in claim 2 in which the agricultural chemical is a herbicide and is being applied to established weeds. 7 A method as claimed in claim 5 in which the herbicide is of the bipyridylium type. 8 A method as claimed in claim 5 in which the herbicide is glyphosate. 9 A method as claimed in any one of claims 1-8 in which the agricultural chemical and the additive surfactant and/or coating agent are applied by spraying onto plants. 10 A method as claimed in any one of claims 1-9 in which an agricultural chemical not containing -an additive as defined in claim 1 is applied not more than fifteen days before and not more than fifteen days after a mixture of an agricultural chemical and an additive as defined in claim 1. 11 An agricultural composition suitable for application, either as such or diluted, to plants, characterised in that it contains an agricultural chemical as defined in claim 1 together with an additive as defined in claim 1. 12 The composition as claimed in claim 11 in which the additive is as defined in claim 2. O PI /., WIPO .* 13 A composition as claimed in claim 12 in which the agricultural chemical is chlorocholine chloride. 14 A composition as claimed in claim 12 in which the agricultural chemical is a herbicide of the bipyridylium type. 15 A composition as claimed in claim 12 in which the agricultural chemical is the herbicide glyphosate. 16 A composition as claimed in any one of claims 11-15, that also includes a purgative or emetic to decrease its toxicity hazard to mammals. 17 A composition as claimed i claims 11-16 in the form of a sprayable liquid. 18 A composition as claimed in any one of claims 11-17 also mixed with a second agricultural chemical whereby toxic risk to mammals is reduced-. 19 A method as claimed in any one of claims 1-9 in which the application is made to plants not less than two weeks before the stage of plant growth or time of fungal or insect infestation at which the agricultural chemiάa-1. ould have been applied without the use of an additive or additives as claimed in claim 2. 20 The method as claimed in any one of claims 1-5 in which the agricultural chemical is chlorocholine chloride and the application is made during the autumn or winter months preceding the spring in which the growth regulator would normally have been applied.

Inventors: SAMPSON M
Applicants: SAMPSON M
Application year: 1980
Main classification: A01N25
IPC codes: A01N25, A01N33, A01N43, A01N57