Solid composition comprising particles of silicate and diutan gum

Abstract

The present invention is related to a solid composition comprising: - particles of at least one silicate, and - diutan gum. The present invention also discloses a method for treating a seed and / or a plant wherein such a composition is applied directly onto or next to at least one seed or at least one part of a plant, or is dispersed just before application with a liquid diluent comprising water or a mixture of water and one or more organic fluid(s), or is mixed just before application with another agrochemical composition.

Description

[0001] SOLID COMPOSITION COMPRISING PARTICLES OF SILICATE AND DIUTAN GUM

[0002] The present invention is related to a solid composition comprising particles of at least one silicate and diutan gum.

[0003] Solid compositions, notably wettable powders (WP) and water dispersible granules (WG or WDG), are encountered in a variety of industries, including agrochemicals. Agrochemical compositions comprising mineral components such as silicates is known by those skilled in the art.

[0004] As example, a method of preparation of herbicidal granules with "active agents" is demonstrated in WO 93 / 05652.

[0005] Also, US patent US6677399 describes agrochemical formulations in solid granular form including styrene (meth)acrylic copolymers as dispersing agents.

[0006] Silicate particles, as inorganic components, are not soluble in majority of liquid mediums used to dilute or disperse solid compositions in agrochemical field. Besides, the final concentration of insoluble particles after dispersion in a liquid medium may be a drawback when solid compositions is developed. Solid compositions are advantageous when considering it can be easily stored and transported, besides advantages on less problems of stability and waste disposal of packaging materials.

[0007] However, for agrochemical applications solid compositions exhibit some disadvantages mainly directed to its suspensibility, which means, when the solid composition is dispersed in a liquid medium, in case of spraying application is selected, it must be capable of maintaining not soluble particles under suspension throughout the time of being applied in the field, i.e. in the soil, seeds or plants. Generally, the addition of dispersant is performed as a way to try to guarantee the suspensibility of particles. Particularly, the suspensibility is important not only to guarantee correct dose application, but also to avoid equipment clogging due to particles aggregation and sedimentation.

[0008] There is a continuous need to provide improved compositions for agriculture needs, particularly solid compositions, notably on its suspensibility after dilution which must last from the moment of their dispersion until the end of the application.

[0009] Pursuing its research in this field, the Applicant has been now discovered that solid compositions comprising silicate particles and diutan gum are capable of exhibit improved suspensibility without solid sedimentation, avoiding equipment clogging and dosing problems during application.

[0010] Therefore, the first object of the present invention concerns a solid composition comprising:

[0011] - particles of at least one silicate, and

[0012] - diutan gum.

[0013] Plant, soil and seed treatments are used on almost every commercial crop on the market today.

[0014] The present invention also concerns a method for treating a seed and / or a plant wherein a composition as defined in the invention is applied directly onto or next to at least one seed or at least one part of a plant, or is dispersed just before application with a liquid diluent comprising water or a mixture of water and organic solvent, or is mixed just before application with another agrochemical composition.

[0015] Last, another object of the present invention concerns the use of the composition to improve the germination of seeds.

[0016] Other subjects, characteristics, aspects and advantages of the invention will emerge even more clearly on reading the description and the examples that follow.

[0017] In the present description, and unless otherwise indicated:

[0018] - the expression "at least one" is equivalent to the expression "one or more" and can be replaced therewith;

[0019] - the expression "between" is equivalent to the expression "ranging from" and can be replaced therewith and implies that the limits of the range are included.

[0020] - the expression “weight percent,” “wt%,” “percent by weight,” “% by weight,” and variations thereof refer to the concentration of a substance as the weight of that substance divided by the total weight of the composition and multiplied by 100.

[0021] - the expression "comprising one" or “comprising an" should be understood as being synonymous with the term "comprising at least one", unless otherwise specified, "between" and “from... to...” should be understood as being inclusive of the limits.

[0022] - the expression “dilution” or dispersion” as used herein, should be understood as synonymous and meaning a mixture of a liquid carrier or liquid medium in a solid or powder which can spread across the area where the mixture occurs.

[0023] The solid composition according to the invention may be in the form of a powder, a particle, an agglomerate, a flake, a granule, a pellet, a tablet, a brick, a paste, a block such as a molded block, a unit dose, or another solid form known to those of skill in the art. Preferably, the solid composition is in the form of a powder or a granule.

[0024] In some aspects, the solid composition is in the form of a granule. Granules compositions may be prepared in a three-step procedure: wet granulation followed by drying and sieving. The wet granulation step notably involves introduction and mixing of silicates, diutan gum and a carrier, and optionally a suspending agent and / or other ingredients, in granulation equipment (such as a mixing granulator). The mixing is conducted with spraying of water to the mixture. The wet granulation step will yield wet granules containing silicate and diutan gum. The weight ratio between the silicate and carrier which are to be mixed may be between 15: 1 to 1 : 1, preferably, between 10: 1 to 1 : 1. The water content introduced may be between 10 wt% to 50 wt% based on the total weight of the wet granules. The carrier may be silicon dioxide, amorphous silica, precipitated silica, hydrated amorphous silica, precipitated silica, hydrated amorphous synthetic calcium silicate, hydrofobized precipitated silica, silica gel, sodium aluminium silicate, clay, zeolite, bentonite, layered silicate, caolim, sodium carbonate, sodium bicarbonate, sodium sulfate, sodium tripolyphosphate, sodium chloride, sodium silicate (water glass), magnesium chloride, calcium chloride, ammonium chloride, magnesium sulfate, calcium carbonate, calcium oxide, and / or calcium sulphate, or a mixture thereof. Notably, the carrier is selected from sodium bicarbonate, caolim and silicon dioxide. The drying step notably involves drying the wet granules by using hot air flow. This step can usually be conducted in a fluid bed equipped with an air inlet and an air outlet. The sieving step may be conducted by using a vibrating plate.

[0025] Alternatively, other suitable granule preparation techniques may be utilized to prepare the composition according to the present invention. Equipment that may be utilized can include but are not limited to fluidized beds, spray driers and pan granulator. It is appreciated that any suitable equipment or technique known by a person skilled in the art may be employed.

[0026] The granules may have a diameter of 0.1 to 2 cm. Generally, normal granules have a diameter of 0.1-1.5 cm and micro granules have a diameter of 0.1-2 mm. Preferably, granules having a diameter of 0.1- 2.0 cm are used.

[0027] Alternatively, the granules containing silicate and diutan gum may be prepared by using extrusion methods well known by a person skilled in the art. The extrusion methods are described in U.S. Patent US6146570. For example, the silicate, diutan gum and the carrier, and optionally a suspending agent and / or other ingredients, may be blended with heating. The weight ratio between the silicates and carrier may be between 15: 1 to 1 : 1. Then a binder may be melted and introduced into the mixture of the silicate, diutan gum and the carrier. Then, an extrusion step may be carried out with extruder temperature maintained between 55°C and 65°C. The soft warm granules may be formed and may be subsequently cooled below solidification point of the molten binder (at room temperature for instance) in order to obtain solid granules.

[0028] According to a most preferred embodiment the composition is in the form of wettable powders (WP) or water dispersible granules (WG or WDG).

[0029] The solid composition according to the invention preferably further comprises one or more suspending agent(s).

[0030] Indeed, it was observed, totally unexpected, that the use of a combination of diutan gum and a suspending agent was able to improve in a significant way the suspensibility of the composition after dispersion, in a way that no aggregation / sedimentation of parti cles / solid was obtained with its maintenance lasting throughout the time of use of the composition.

[0031] Preferably, the one or more suspending agent are selected from at least one guar derivative, xanthan gum, alginates, carboxylated or hydroxylated methylcelluloses, synthetic macromolecules of the polyacrylate, polymaleate, polyvinylpyrrolidone, polyethylene glycol or polyvinyl alcohol type.

[0032] The expression "guar" is understood to cover guars and guar derivatives, so both expressions are equivalent and can be replaced therewith.

[0033] A guar is a polymer of the family of galactomannans. Galactomannans are polysaccharides consisting mainly of the monosaccharides mannose and galactose. The backbone is a linear chain of P 1,4-linked mannose residues to which galactose residues are 1,6-linked at every second mannose in average, forming short side units. Naturally occurring galactomannans are available from numerous sources, including guar gum, guar splits, locust bean gum and tara gum, flame tree gum and cassia gum.

[0034] Additionally, galactomannans may also be obtained by classical synthetic routes or may be obtained by chemical modification of naturally occurring galactomannans.

[0035] Guar gum refers to the mucilage found in the seed of the leguminous plant Cyamopsis tetragonolobus. The water soluble fraction (85%) is called “guaran,” which consists of linear chains of (1,4)-P-D mannopyranosyl units- with a-D-galactopyranosyl units attached by (1,6) linkages. The ratio of D- galactose to D-mannose in guaran is 1 :2.

[0036] In the present application, “native guar” designates macromolecular chains of the galactomannan type, derived from guar endosperm, not having been subjected to chemical modification by the grafting of chemical groups. Native guar comprises macromolecules containing a principal chain of D- mannopyranose units linked in the beta (1-4) position substituted by D- galactopyranose units in the beta (1-6) position. Native guar has a mannose / galactose ratio of 2. In the present application, “guar gum” designates a product substantially consisting of native guar, in the form of guar splits, or of guar flour or powder. Processes for making derivatives of guar gum splits are generally known. Typically, guar splits are reacted with one or more derivatizing agents under appropriate reaction conditions to produce a guar polysaccharide having the desired substituent groups. Suitable derivatizing reagents are commercially available and typically contain a reactive functional group, such as an epoxy group, a chlorohydrin group, or an ethylenically unsaturated group, and at least one other substituent group, such as a cationic, nonionic or anionic substituent group, or a precursor of such a substituent group per molecule, wherein substituent group may be linked to the reactive functional group of the derivatizing agent by bivalent linking group, such as an alkylene or oxyalkylene group. Suitable cationic substituent groups include primary, secondary, or tertiary amino groups or quaternary ammonium, sulfonium, or phosphinium groups. Suitable nonionic substituent groups include hydroxyalkyl groups, such as hydroxypropyl groups. Suitable anionic groups include carboxyalkyl groups, such as carboxymethyl groups. The cationic, nonionic and / or anionic substituent groups may be introduced to the guar polysaccharide chains via a series of reactions or by simultaneous reactions with the respective appropriate derivatizing agents.

[0037] The guar may be treated with a crosslinking agent, such for example, borax (sodium tetra borate) is commonly used as a processing aid in the reaction step of the water-splits process to partially crosslink the surface of the guar splits and thereby reduces the amount of water absorbed by the guar splits during processing. Other crosslinkers, such as, for example, glyoxal or titanate compounds, are known.

[0038] According to one embodiment, the one or more suspending agent is a guar, particularly guar gum.

[0039] It may be especially guar gum having an average molecular weight (Mw) of between 2,000 Daltons and 90,000 Daltons. Preferably, the guar gum may have an average molecular weight of between 5,000 Daltons and 60,000 Daltons, more preferably, the guar gum may have an average molecular weight of between 5,000 Daltons and 40,000 Daltons, still more preferably, the guar gum may have an average molecular weight of between 8,000 Daltons and 30,000 Daltons.

[0040] As used herein, the “average molecular weight” of the guar means the weight average molecular weight of said guar.

[0041] The average molecular weight of the guar gum may be measured by GPC (Gel Permeation Chromatography). Measurements may be carried out using Shodex OH Pak columns and Agilent Refractive Index Detector, for instance with the conditions detailed in the examples.

[0042] The guar gum according to the present invention may be prepared by depolymerizing natural guars that have high molecular weight, so as to “split” the guar polymers to desired sizes. Various depolymerisation methods are well known in the art and may be used for the present invention, such as treatment by using peroxo compound (e.g., hydrogen peroxide) and irradiation. Examples of such methods are disclosed in U.S. Pat. No. 4,547,571, U.S. Pat. No. 6,383,344 and U.S. Pat. No. 7,259, 192. Various methods for cross-linking guars are also known, see for example U.S. Pat. No. 5,532,350 and U.S. Pat. No. 5,801,116. Alternatively, low molecular weight guars can be obtained by harvesting guar beans which are still at an early developmental stage such that the harvested guar beans contain low molecular weight natural guar gums.

[0043] Advantageously such low molecular weight guar gum may be compliant or suitable for organic farming.

[0044] In another embodiment, the one or more suspending agent of the invention is a derivatized guar derivative that is substituted at one or more sites of the polysaccharide with a substituent group that is independently selected for each site from the group consisting of cationic substituent groups, nonionic substituent groups, and anionic substituent groups.

[0045] According to a preferred embodiment, the one or more suspending agent of the composition of the present invention is at least one guar derivative, preferably derivatized guars selected from a cationic guar, a nonionic guar, an anionic guar and mixtures thereof.

[0046] In a particular preferred embodiment, the derivatized guars are chosen from the group consisting of: hydroxypropyl trimethyl ammonium guar, hydroxypropyl lauryldimethylammonium guar, hydroxypropyl stearyldimethylammonium guar, hydroxypropyl guar, carboxymethyl guar, guar with hydroxypropyl groups and hydroxypropyl trimethylammonium groups, guar with carboxymethyl hydroxypropyl groups and mixtures thereof.

[0047] The amount of derivatizing groups in a derivatized polysaccharide polymer may be characterized by the degree of substitution of the derivatized polysaccharide polymer or the molar substitution of the derivatized polysaccharide polymer.

[0048] As used herein, the terminology “degree of substitution” in reference to a given type of derivatizing group and a given polysaccharide polymer means the number of the average number of such derivatizing groups attached to each monomeric unit of the polysaccharide polymer. In one embodiment, the derivatized guar derivative exhibits a total degree of substitution (“DST”) of from 0.001 to 3.0, wherein:

[0049] DST is the sum of the DS for cationic substituent groups (“D Scationic”), the DS for nonionic substituent groups (“DSnonionic”) and the DS for anionic substituent groups (“DSanionic”),

[0050] DScationic is from 0 to 3, more typically from 0.001 to 2.0, and even more typically from 0.001 to 1.0,

[0051] DSnonionic is from 0 to 3.0, more typically from 0.001 to 2.5, and even more typically from 0.001 to 1.0, and

[0052] DSanionic is from 0 to 3.0, more typically from 0.001 to 2.0.

[0053] According to an embodiment of the invention, the degree of substitution of the derivatized guar is comprised between 0.01 and 3.0, for instance between 0.05 and 1.5.

[0054] As used herein, the term “molar substitution” or “ms” refers to the number of moles of derivatizing groups per moles of monosaccharide units of the guar. The molar substitution can be determined by the Zeisel-GC method. The molar substitution utilized by the present invention is typically in the range of from 0.001 to 3.

[0055] According to the invention embodiments, the guar has typically a weight average molecular weight (Mw) ranging from 2,000 to 3,000,000 g / mol. In some embodiments, it can be interesting to target a low molecular weight guar, having an average molecular weight of between 2,000 g / mol and 90,000 g / mol, preferably between 5,000 and 90,000 g / mol, more preferably between 5,000 and 60,000 g / mol, still more preferably between 5,000 and 50,000 g / mol, notably of between 7,000 and 40,000 g / mol.

[0056] Alternatively, it can be interesting to target a high molecular weight guar, having an average molecular weight of between 100,000 g / mol and 4,000,000 g / mol, for instance between 100,000 g / mol and 3,000,000 g / mol, for instance between 150,000 g / mol and 4,000,000 g / mol, for instance between 150,000 g / mol and 3,000,000 g / mol, for instance between 200,000 g / mol and 4,000,000 g / mol, for instance between 200,000 g / mol and 3,000,000 g / mol.

[0057] The average molecular weight of the derivatized guar of the invention may be measured for instance by SEC-MALS or by using gel permeation chromatography.

[0058] In a particular embodiment, the amount of one or more suspending agent ranges from 0.05 to 1%, preferably from 0.1 to 0.5% by weight based on the total weight of the composition.

[0059] The solid composition of the present invention contains solid particles of one or more silicate(s).

[0060] The silicate is preferably selected from the group consisting of micas, aluminosilicates, tourmalines, serpentines and mixtures thereof.

[0061] The aluminosilicates can belong to clays or not.

[0062] Among the aluminosilicates, mention can be made of some groups such as feldspars, zeolites and kaolinites, and of specific aluminosilicates such as for example petalite, prehnite, delhayelite, bannisterite, allophane, crysocolla, minehillite, wickendurgite, franklinphilite.

[0063] Among the aluminosilicates from clay materials, besides the kaolinites, mention can be made of minerals from chlorite group, illite, glauconite, montmorillonite, palygorskite, pyrophyllite, Sauconite and vermiculite.

[0064] According to a most preferred embodiment, the silicate is selected from the group consisting of tourmalines. Tourmalines are crystalline boron silicate minerals compounded with elements such as aluminum, iron, magnesium, sodium, lithium, or potassium. We can cite Schorl, Dravite and Elbaite species.

[0065] The D90 size of the particles of silicate preferably ranges from 0.1 to 30 pm, preferably from 0.5 to 20 pm, more preferably from 1 to 15 pm, even more preferably from 2 to 10 pm and most preferably from 5 to 7 pm.

[0066] In a manner known per se in the field of particle size analysis, D90 designates the point in the volume size distribution of a population of particles, up to and including which, 90% of the total population is contained. In other words, D90 is defined by the value in the particle size distribution of a sample where 90% of the particles present in the sample are equal or below that value. For example, a sample of particles having a D90 of 1 pm means that 90% by volume of the sample has a size of 1 pm or smaller.

[0067] The size distribution of a sample of particles can be measured using the laser diffraction particle size analysis method (using, for example, Malvern or Cilas particle size analyzers). One advantageous way to carry out the process consists in suspending the particles in water and in determining their particle size by laser diffraction using the method described in standard ISO 13320:2009.

[0068] The particles of at least one silicate represent from 65 to 85% by weight with regard to the total weight of the composition, preferably from 70 to 80% by weight, with regard to the total weight of the composition. The above quantities are defined for the composition before any dilution that could be performed before application onto plants and / or seeds and / or soil.

[0069] The composition of the invention further contains diutan gum.

[0070] Diutan gum is a natural high-molecular-weight polysaccharide produced by carefully controlled aerobic fermentation, specifically via fermentation of strain Sphingomonas sp. ATCC 53159.

[0071] The repeating unit of diutan gum is composed of a six-sugar unit. A tetrasaccharide backbone structure that contains L-mannose, L-rhamnose, D- glucose and D-glucuronic acid while the side chain contains two L-rhamnose. Progress has been made in elucidating the genetics and biochemistry underlying biosynthesis of diutan gum. A cluster of genes involved in biosynthesis of diutan has been identified that includes genes for glycosyl transferases, genes encoding enzymes for synthesis of a precursor molecule dTDP rhamnose, and genes for secretion of the polysaccharide.

[0072] The above diutan gum is well known in the art and is commercially available and is currently used mainly in cement and concrete.

[0073] In a preferred embodiment, the amount of diutan gum ranges from 0.05 to 5%, preferably from 1 to 2% by weight, based on the total weight of the composition.

[0074] In some aspects, the molecular weight of diutan gum is 2.88 to 5.18 million Daltons.

[0075] In one embodiment, the composition of the invention further comprises one or more active compound selected from fertilizers, organominerals, biostimulants, biopesticides and mixtures thereof.

[0076] According to one embodiment, the one or more fertilizers are chosen from water-soluble fertilizers such as for example foliar fertilizers (fertilizers which are taken up by the leaves of the plants), such as urea or foliar macro- or microelement fertilizer, including chelates. Fertilizers are generally used for foliar and soil applications.

[0077] According to another embodiment, the composition of the invention may further contain one or more organominerals. As used herein, the term “organominerals” should be understood as a mineral product whose formation is induced by byproducts of biological activity, dead and decaying organisms, or nonbiological organic compounds, to be distinguished from the biomineral components of living organisms. Useful organominerals may be chosen from fulvic acid, humic acid, and organic wastes in general.

[0078] According to another embodiment, the composition according to the present invention may further contain one or more biostimulant or biopesticide, such as microorganisms. Useful microorganisms may be chosen, in a non- limitative manner, among the following: Trichoderma harzianum, Beauveria bassiana, Metarhizium anisopliae, Bacillus thuringiensis, Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus sphaericus, Bacillus popilliae, Bacillus cereus, Pseudomonas fluorescens, Serratia marcescens, Escherichia coli, Bacillus megaterim, Bradyrhizobium japonicum, and Pseudomonas putida species.

[0079] By “microorganism” is meant herein a microscopic organism which may exist in its single-cell form or as a colony of cells. In a particular embodiment, said microorganism is unicellular.

[0080] The composition may further contain additional ingredients, which can be chosen from all additives and adjuvants useful in agrochemical compositions such as for example anti-foaming agents; organic fluids such as alcohols, polyols and saccharides; colorants such as pigments, surfactants, nutrients such as algae extract, aminoacids, cobalt, molybdenum, micronutrients; pesticides such as herbicides, insecticides and fungicides; etc. . .

[0081] All the amounts above are defined considering a solid composition. Particularly, the above solid composition according to the invention can be dispersed before an application onto the crop, onto the leaves of the plant, for use in the soil or onto the seeds. Advantageously the composition can be mixed together with other compositions (e.g. fungicide compositions, nutrient compositions, etc, which generally contain a liquid carrier).

[0082] The components of the composition as defined above may be used in a solid composition.

[0083] In one embodiment, the solid composition comprising at least one silicate and diutan gum is used in a liquid or solid form.

[0084] For a ready-to-use composition, the solid composition according to the present invention is applied directly onto or next to the seeds or at least one part of a plant.

[0085] Alternatively, the composition according to the invention can be dispersed to be applied by spraying by simple disintegration and dispersion of wettable powders (WP) or water dispersible granules (WG and WDG) into a liquid diluent or an agrochemical composition.

[0086] Commonly, agrochemical compositions are applied by spraying in a liquid diluent, in which such a composition may be dissolved, dispersed or emulsified. Notably, the diluent can be made of water, or of water mixed with one or more organic fluid(s), which can be water-miscible or not.

[0087] When the diluent contains water and one or more water-immiscible organic fluid(s), said carrier may be in the form of an emulsion.

[0088] The organic fluids can be for example chosen from natural or synthetic oils, in particular mineral oils, vegetable oils, fatty or non fatty alcohols, fatty acids, esters containing at least one fatty acid and / or at least one fatty alcohol.

[0089] The fatty alcohols and fatty acids mentioned above are those which contain from 8 to 32, preferably from 10 to 26 and more preferentially from 12 to 22 carbon atoms.

[0090] It is of course possible to use mixtures of organic fluids and in particular any mixtures of any of the fluids described above.

[0091] According to one particularly preferred embodiment, the diluent of the composition used in the present invention is water.

[0092] Advantageously, after dispersion of the solid composition, the obtained diluted composition may be adjusted in terms of concentration of diluted composition in a manner well know by person in the art.

[0093] For a solid composition dispersed just before application with a liquid diluent comprising water or a mixture of water and organic solvent, or mixed just before application with another agrochemical composition, the resulted liquid composition according to the present invention is applied directly onto or next to the seeds or at least one part of a plant.

[0094] The dilution may be considered by a skilled person in the art according to the need and target of application of the composition of the invention. Typically, dilution from 2 to 3 g silicate / kg seeds, for seeds application; and from 0.15 to 2.0 kg silicate / ha for soil or foliar / plant applications.

[0095] The present invention also concerns a method for treating a seed and / or a plant wherein a composition as described above is applied directly onto or next to at least one seed or at least one part of a plant, or is dispersed just before application with a liquid diluent comprising water or a mixture of water and with one or more organic fluid(s), or is mixed just before application with another agrochemical composition. The method of the present invention can be implemented on any type of seed or plant. The seeds or plants are preferably chosen among agricultural and horticultural plants, shrubs, trees and grasses.

[0096] In one embodiment, the seed is of the crop or plant species including but not limited to corn (Zea mays), Brassica sp. (e.g., B. napus, B. rapa, B. juncea), alfalfa (Medicago sativa), rice (Oryza sativa), rye (Secale cereale), sorghum (Sorghum bicolor, Sorghum vulgare), millet (e.g., pearl millet (Pennisetum glaucum), proso millet (Panicum miliaceum), foxtail millet (Setaria italica), finger millet (Eleusine coracana)), sunflower (Helianthus annuus), safflower (Carthamus tinctorius), wheat (Triticum aestivum), soybean (Glycine max), tobacco (Nicotiana tabacum), potato (Solanum tuberosum), peanuts (Arachis hypogaea), cotton (Gossypium barbadense, Gossypium hirsutum), sweet potato (Ipomoea batatus), cassava (Manihot esculenta), coffee (Cofea spp.), coconut (Cocos nucifera), pineapple (Ananas comosus), citrus trees (Citrus spp.), cocoa (Theobroma cacao), tea (Camellia sinensis), banana (Musa spp.), avocado (Persea americana), fig (Ficus casica), guava (Psidium guajava), mango (Mangifera indica), olive (Olea europaea), papaya (Carica papaya), cashew (Anacardium occidentale), macadamia (Macadamia integrifolia), almond (Prunus amygdalus), sugar beets (Beta vulgaris), sugarcane (Saccharum spp.), canola, oats, barley, vegetables, ornamentals, woody plants such as conifers and deciduous trees, squash, pumpkin, hemp, zucchini, apple, pear, quince, melon, plum, cherry, peach, nectarine, apricot, strawberry, grape, raspberry, blackberry, sorghum, sugarcane, rapeseed, clover, carrot, and Arabidopsis thaliana.

[0097] Further examples of seeds or plants is of any vegetables species including but not limited to tomatoes (Lycopersicon esculentum), lettuce (e.g., Lactuca sativa), green beans (Phaseolus vulgaris), lima beans (Phaseolus limensis), peas (Lathyrus spp.), cauliflower, broccoli, turnip, radish, spinach, cabbage, asparagus, onion, garlic, pepper, celery, and members of the genus Cucumis such as cucumber (C. sativus), cantaloupe (C. cantalupensis), and musk melon (C. melo). Mention can further be made of seeds or plants of ornamentals species including but not limited to hydrangea (Macrophylla hydrangea), hibiscus (Hibiscus rosasanensis), petunias (Petunia hybrida), roses (Rosa spp.), azalea (Rhododendron spp.), tulips (Tulipa spp.), daffodils (Narcissus spp.), carnation (Dianthus caryophyllus), poinsettia (Euphorbia pulcherrima), and chrysanthemum; and of conifer species including but not limited to conifers pines such as loblolly pine (Pinus taeda), slash pine (Pinus elliotii), ponderosa pine (Pinus ponderosa), lodgepole pine (Pinus contorta), and Monterey pine (Pinus radiata), Douglas-fir (Pseudotsuga menziesii); Western hemlock (Tsuga canadensis); Sitka spruce (Picea glauca); redwood (Sequoia sempervirens); true firs such as silver fir (Abies amabilis) and balsam fir (Abies balsamea); and cedars such as Western red cedar (Thuja plicata) and Alaska yellow-cedar (Chamaecyparis nootkatensis).

[0098] In one embodiment, the seed or plant is chosen from leguminous plant species including but not limited beans and peas. Beans include guar, locust bean, fenugreek, soybean, garden beans, cowpea, mungbean, lima bean, fava bean, lentils, chickpea, green pea, moth bean, broad bean, kidney bean, lentil, dry bean, etc. Legumes include, but are not limited to, Arachis, e.g., peanuts, Vicia, e.g., crown vetch, hairy vetch, adzuki bean, mung bean, and chickpea, Lupinus, e.g., lupine, trifolium, Phaseolus, e.g., common bean and lima bean, Pisum, e.g., field bean, Melilotus, e.g., clover, Medicago, e.g., alfalfa, Lotus, e.g., trefoil, lens, e.g., lentil, and false indigo. Typical forage and turf grass for use in the methods described herein include but are not limited to alfalfa, orchard grass, tall fescue, perennial ryegrass, creeping bent grass, lucerne, birdsfoot trefoil, clover, stylosanthes species, lotononis bainessii, sainfoin and redtop. Other grass species include barley, wheat, oat, rye, orchard grass, guinea grass, sorghum or turf grass plant.

[0099] According to a preferred embodiment, the seed or plant is selected from the group consisting of soy, cane, cotton, wheat, beans, rice, and preferably the plant is soy.

[0100] It is understood that the term “seed” or “seedling” is not limited to a specific or particular type of species or seed. The term “seed” or “seedling” can refer to seed from a single plant species, a mixture of seed from multiple plant species, or a seed blend from various strains within a plant species. In one embodiment, crop seeds include but are not limited to rice, corn, wheat, barley, oats, soybean, cotton, sunflower, alfalfa, sorghum, rapeseed, sugarbeet, tomato, bean, carrot, tobacco or flower seeds.

[0101] In a general manner, the composition of the invention can be easily applied onto plants or parts thereof using any conventional and commercially available application equipment.

[0102] Typically, the composition of the present invention can be applied onto or next to seeds.

[0103] In one embodiment, the method of the present invention comprises a step in which the seed is coated with the composition as described above. Then the coated seed may be applied onto or in the soil, notably, in order to set in contact the coated seed with the ground.

[0104] Suitable coating techniques may be utilized to coat the seed or agglomeration of the seeds with the composition according to the present invention. Equipment that may be utilized for coating can include but are not limited to drum coaters, rotary coaters, tumbling drums, fluidized beds and spouted beds. It is appreciated that any suitable equipment or technique known by a person skilled in the art may be employed. The seed may be coated via a batch or continuous coating process. The seed may be coated with the composition according to the present invention.

[0105] One advantage of the present invention is that the solid composition after dispersion according to the present invention has excellent suspensibility and, thus, delivers the desired dosage and can be conveniently used for treating the seeds or the soil.

[0106] As used herein, the term "suspensibility" designates the amount of particles that remains as a suspension after 30 min. The reference method used to determine the supensibility was Brazilian standard ABNT NBR 13313.

[0107] The seeds may be separated prior to the coating step. In one embodiment, mechanical means, such as a sieve, may be employed for separating the seeds. The separated seeds can then be introduced into a coating machine having a seed reservoir. In one embodiment, the seeds are combined with the composition described herein, optionally with a binder and / or adhesive, in a mixing bowl.

[0108] In some aspects, one or more layers of coating which comprises the composition according to the present invention may be added onto the seeds or the agglomeration thereof. Outer layers can be introduced sequentially by coating the seeds or the agglomeration thereof in a rotating drum.

[0109] Agglomerators or agglomerator devices may also be utilized. Coating may be performed within a rotary coater by placing the seeds within a rotating chamber, which pushes the seeds against the inside wall of the chamber. Centrifugal forces and mixing bars placed inside the coater allow the seeds to rotate and mix with a coating layer comprising the composition according to the present invention. Binder or other coating materials can be pumped into the proximate center of the coater onto an atomizer disk that rotates along with the coating chamber. Upon hitting the atomizer disk, liquid adhesive is then directed outward in small drops onto the seeds.

[0110] Seed coating techniques also include, for example, placing the seeds in a rotating pan or drum. The seeds are then mist with water or other liquid, and then gradually a fine inert powder, e.g., diatomaceous earth, is added to the coating pan. Each misted seed becomes the center of a mass of powder, layers, or coatings that gradually increases in size. The mass is then rounded and smoothed by the tumbling action in the pan, similar to pebbles on the beach. The coating layers are compacted by compression from the weight of material in the pan. Binders often are incorporated near the end of the coating process to harden the outer layer of the mass. Binders can also reduce the amount of dust produced by the finished product in handling, shipping and sowing. Screening techniques, such as frequent hand screening, are often times utilized to eliminate blanks or doubles, and to ensure uniform size. For example, tolerance for seed coating compositions described herein can be + / -1 / 64 inch (0.4mm), which is the US seed trade standard for sizing, established long before coatings were introduced. For example, coated lettuce seed is sown most frequently with a belt planter through an 8 / 64 inch (3.2 mm) diameter round holes in the belt. This hole size requires that the lettuce seeds coated with the composition according to the present invention can be sized over a 7.5 / 64 inch (3.0 mm) screen and through an 8.5 / 64 inch (3.4 mm) screen.

[0111] In one embodiment of the present invention, the seed may be contacted with the composition by using an “in situ coating” process, notably by implanting in a hole or “in-furrow” in the soil a seed of a plant, and then applying the composition according to the present invention to surround or partially surround, or to be adjacent to the seed, so that the seed come into contact with the composition, notably with the silicate particles. According to the invention, the hole or furrow may notably be a hole, a cavity or a hollowed area. The seed may be one that has not be treated by any agent, or a seed that has been treated with an agrochemical (such as fungicide and insecticide) and that has not been treated with the composition of the present invention. Preferably, the composition is in liquid form, such as in the form of aqueous suspension.

[0112] In still another embodiment, the composition according to the present invention is administered to a soil in which a plant is cultivated. Then the seeds of the plant can be applied to the soil so that the seeds will come into contact with the composition, particularly with the silicate particles. Notably, the composition is in solid or liquid form. When in the liquid form, aqueous suspension may be used.

[0113] Preferably, the application of the seed and the application of the composition according to the present invention are performed mechanically. It is appreciated that either or both of the referenced applications can be performed manually as well.

[0114] In a particular preferred embodiment, the composition is applied onto or next to a seed, preferably by coating the seed with the composition or by directly applying the composition in-furrow of seed planting immediately before, during or immediately after planting a seed in the furrow.

[0115] In one embodiment of the present invention, the silicate is used in an amount ranging from 240 to 1360 g / quintal seed. The composition of the invention can be applied on the plant at any stage of its development. It can be applied on the whole plant or on parts thereof.

[0116] According to a preferred embodiment, the composition is applied onto the foliar system of the plant. Such application is preferably carried out by spraying a composition as disclosed above onto the leaves of the plant. For example, the composition can be sprayed onto a field using appropriate means well known in agriculture.

[0117] In a general manner, the composition of the invention can be easily applied onto or next to plants or parts thereof using any conventional and commercially available application equipment.

[0118] The invention also concerns the use of a solid composition as disclosed above for improving the germination of seeds.

[0119] In one preferred embodiment, the use of the composition as disclosed above leads to an improvement in the germination of seeds treated with such a composition and consequently, not only enhancing the yield of the crop, but also enhancing the growth of the obtained plant, notably permitting to develop and to increase its biomass.

[0120] Advantageously, microorganisms such as biostimulants help enhance plant growth by providing nutrients from natural products or by helping plants to access nutrients.

[0121] Finally, the invention also concerns the use of a solid composition as disclosed above for maintaining or increasing the growth rate of microorganisms on a plant, on a seed or in the soil.

[0122] The above description of the method of the invention also applies to the use according to the invention.

[0123] Should the disclosure of any patents, patent applications, and publications which are incorporated herein by reference conflict with the description of the present application to the extent that it may render a term unclear, the present description shall take precedence.

[0124] The examples of implementation of the invention below are given purely by way of illustration and shall not be interpreted at limiting the scope thereof. EXAMPLES A series of compositions (samples SI to S3), including comparative composition (sample SI) were prepared and evaluated according to suspensibility. Comparative composition (sample SI) was prepared without the addition of diutan gum and suspending agent. TABLE 1 summarizes the samples.

[0125] Materials:

[0126] The minerals used in the below described experiments is a powder of black tourmaline from Micro Service - Tecnologica em Micronizagao, Produtos e Processos Industrials with D90 = 6 pm (referenced as G2g below).

[0127] Other compound used to prepare samples:

[0128] - Silicon dioxide - Tixosil® 43 B from Solvay

[0129] - Caolim - Caulim coat 87 from Monte Pascal

[0130] - Polynaphthalenmethan-sulphonate - Supragil® RM / 210-EL from Solvay

[0131] - Dispersant containing sodium polycarboxylate in aqueous solution at a concentration of 90% by weight - Geropon® T / 36 from Solvay

[0132] - Diutan gum at a concentration of 1% by weight in aqueous solution - Kelco-Vis® DG from CP Kelco

[0133] - Hydroxypropyl guar - Jaguar® HP 105 from Solvay.

[0134] EXAMPLE 1: Preparation of compositions

[0135] Different samples of solid composition were prepared by adding the components and thoroughly mixing in a planetary mixer until achieving visual homogeneity. Water was gradually added to achieve a paste-like consistency. The resulting formulation was then passed through a basket extruder to form the granules. The granules were dried using a fluidized bed batch scale.

[0136] Different samples are demonstrated in TABLE 1 below: TABLE 1 : Solid compositions

[0137] EXAMPLE 2: Suspensibility Evaluation

[0138] The suspensibility evaluation of the samples was determined according to the Brazilian standard ABNT NBR 13313. The results obtained are detailed in TABLE 2 below:

[0139] TABLE 2: Suspensibility results

[0140] It can be seen that sample S2, corresponding to the composition containing diutan gum showed excellent suspensibility after dilution and sample S3 showed even better suspensibility when compared to comparative sample S 1.

[0141] Comparative sample SI corresponding to similar composition but without the addition of diutan gum and suspending agent demonstrated poor suspensibility.

[0142] Solid compositions according to the present invention demonstrated unexpected better suspensibility avoiding aggregation and sedimentation of particles, which could damage equipments and impair the correct dosage administration in the agricultural field.

Claims

C L A I M S1. A solid composition comprising:- particles of at least one silicate, and- diutam gum.

2. The composition of claim 1, wherein the composition is in the form of wettable powders (WP) or water dispersible granules (WG or WDG).

3. The composition of claims 1 or 2, further comprising one or more suspending agent selected from at least one guar derivative, xanthan gum, alginates, carboxylated or hydroxylated methylcelluloses, synthetic macromolecules of the polyacrylate, polymaleate, polyvinylpyrrolidone, polyethylene glycol or polyvinyl alcohol type.

4. The composition of claim 3, wherein the one or more suspending agent is at least one guar derivative, preferably derivatized guars selected from a cationic guar, a nonionic guar, an anionic guar and mixtures thereof.

5. The composition of claim 4, wherein said derivatized guars are chosen from the group consisting of: hydroxypropyl trimethylammonium guar, hydroxypropyl lauryldimethylammonium guar, hydroxypropyl stearyldimethylammonium guar, hydroxypropyl guar, carboxymethyl guar, guar with hydroxypropyl groups and hydroxypropyl trimethylammonium groups, guar with carboxymethyl hydroxypropyl groups and mixtures thereof..

6. The composition of claims 4 or 5, wherein said derivatized guar has a degree of substitution comprised between 0.01 and 3.0, for instance between 0.05 and 1.5.

7. The composition of claims 4 to 6, wherein the derivatized guar has an average molecular weight comprised between 2,000 g / mol and 3,000,000 g / mol.

8. The composition of claims 3 to 7, wherein the amount of each one of the at least one additional suspending agent ranges from 0.05 to 1%, preferably from 0.1 to 0.5% by weight based on the total weight of the composition.

9. The composition of anyone of the preceding claims, wherein the particles of at least one silicate is selected from the group consisting of micas, aluminosilicates, tourmalines, serpentines and mixtures thereof, and preferably from the group consisting of tourmalines.

10. The composition of anyone of the preceding claims, wherein the D90 size of the particles of silicate ranges from 0.1 to 30 pm, preferably from 0.5 to 20 pm, more preferably from 1 to 15 pm, even more preferably from 2 to 10 pm and most preferably from 5 to 7 pm.

11. The composition of anyone of the preceding claims, wherein the particles of at least one silicate represent from 65 to 85% by weight with regard to the total weight of the composition, preferably from 70 to 80% by weight with regard to the total weight of the composition.

12. The composition of anyone of the preceding claims, wherein the amount of diutam gum ranges from 0.05 to 5%, preferably from 1 to 2% by weight, based on the total weight of the composition.

13. The composition of anyone of the preceding claims, further comprising one or more active compound selected from fertilizers, organominerals, biostimulants, biopesticides and mixtures thereof.

14. A method for treating a seed and / or a plant wherein a composition as defined in anyone of the preceding claims is applied directly onto or next to at least one seed or at least one part of a plant, or is dispersed just before application with a liquid diluent comprising water or a mixture of water and one or more organic fluid(s), or is mixed just before application with another agrochemical composition.

15. The method of claim 14, wherein the seed or plant is selected from the group consisting of soy, cane, cotton, wheat, beans, rice, and preferably the seed or plant is soy.

16. The method of anyone of claims 14 or 15, wherein the composition is applied onto or next to the seed, preferably by coating the seeds with the composition or by directly applying the composition in-furrow of seed planting immediately before, during or immediately after planting a seed in the furrow.

17. The method of anyone of claims 14 to 16, wherein the composition is applied onto the foliar system of the plant, preferably by spraying said composition onto the leaves of the plant.

18. Use of a composition of claims 1 to 13 to improve the germination of seeds.

19. Use of a composition of claims 1 to 13 for maintaining or increasing the growth rate of microorganisms on a plant, on a seed or in the soil.

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