biostimulants

Abstract

A biostimulant product containing a synergistic mixture of compounds, plant growth medium comprising the biostimulant product and related methods of preparation and use of the biostimulant product including methods of improving plant health, increasing leaf biomass, improving root development, improving drought resistance, improving crop yield and improving soil health.

Description

[0001] BIOSTIMULANTS

[0002] FIELD OF THE INVENTION

[0003] The present invention relates generally to biostimulant products, plant growth media, and to methods of treating plants and plant growth media with biostimulant products. More particularly, but not exclusively, this invention concerns improved biostimulant products comprising bioflavonoids. It also relates to biostimulant stock compositions comprising bioflavonoids, which stock compositions may be diluted, typically with water, to provide a biostimulant product for treating plants and plant growth media.

[0004] The invention also concerns related methods, uses and further products.

[0005] BACKGROUND OF THE INVENTION

[0006] Various biostimulants have been developed to enhance plant health, soil health and plant crop productivity. Plant health may be increased, and plant growth rates accelerated by using such stimulants. Many compounds and other nutrients (for example, elemental nutrients) have been proposed for use as biostimulants.

[0007] In particular, flavonoids are known in general to have a role in plant stress response and plant microbial associations. They have been proposed for use in inducing resistance to biotic and abiotic stress in plants. Flavonoids are secondary metabolites used by plants as signalling agents with a role in allopathy and communication with rhizosphere microbes (see for example, Shah & Smith (2020) Agronomy 10,1209. http: / / doi.org / 10.3390 / agronomy 10081209).

[0008] The present invention provides, in one of several aspects, improved biostimulant products. Those biostimulant products comprise various phytochemicals including flavonoids (also known as bioflavonoids).

[0009] SUMMARY OF THE INVENTION

[0010] The present invention provides in one aspect a biostimulant product comprising: formulation A and formulation B, wherein formulation B comprises: vanillic acid or a derivative thereof, cinnamic acid or a derivative thereof, dicaffeoylguinic acid or a derivative thereof, coumaroylguinic acid or a derivative thereof, caffeoylguinic acid or a derivative thereof, one or more quercetin glycosides, or one or more derivatives thereof, kaempferol rhamnoside or a derivative thereof, gentisic acid or a derivative thereof, and procyanidin trimer or a derivative thereof; and wherein formulation A comprises: vanillic acid or a derivative thereof, cinnamic acid or a derivate thereof, decaffeoylquinic acid or a derivative thereof, chlorogenic acid or a derivative thereof, coumaroylquinic acid or a derivative thereof, syringic acid or a derivative thereof, procyanidin dimers or a derivative thereof, and prodelphinidin dimers or a derivative thereof.

[0011] This Applicant has surprisingly found that a biostimulant product containing both formulation B and formulation A is advantageous over a biostimulant product containing formulation B only and advantageous over a biostimulant product containing formulation A only. In particular, it has been discovered that formulation A and formulation B have a synergistic effect in promoting soil respiration, and plant growth.

[0012] BRIEF DISCRIPTION OF DRAWINGS

[0013] Figure 1 is a photograph showing visually the effect of biostimulus treatment on leaf growth in rye grass. Columns of pots labelled “control” (no treatment), “A” (treatment with formulation A) or “A+B” (treatment with biostimulus product containing formulation A and formulation B). It can be seen that the plants in the “A + B” column show more vigorous leaf growth than those in the other columns.

[0014] Figure 2 is a photograph showing visually the effect of biostimulus treatment on leaf growth in bluegrass. Columns of pots labelled “control” (no treatment), “A” (treatment with formulation A) or “A+B” (treatment with biostimulus product containing formulation A and formulation B). It can be seen that the plants in the “A + B” column show more vigorous leaf growth than those in the other columns.

[0015] Figure 3 is a photograph showing visually the effect of biostimulus treatment on root development in rye grass. Rows of pots labelled “control” (no treatment), “A” (treatment with formulation A) or “A+B” (treatment with biostimulus product containing formulation A and formulation B). Increasing root development is shown by greater visibility of white roots against the dark compost background. It can be seen that the plants in the “A + B” row show the most vigorous root growth.

[0016] Figure 4 is a photograph showing visually the effect of biostimulus treatment on root development in bluegrass. Rows of pots labelled “control” (no treatment), “A” (treatment with formulation A) or “A+B” (treatment with biostimulus product containing formulation A and formulation B). Increasing root development is shown by greater visibility of white roots against the dark compost background. It can be seen that the plants in the “A + B” column show the most vigorous root growth.

[0017] Figure 5 shows quantification of leaf biomass in bluegrass treated with control (water), formulation A, formulation B or biostimulant product containing formulation A and formulation B.

[0018] Figure 6 shows quantification of leaf biomass in rye grass treated with control (water), formulation A, formulation B or biostimulant product containing formulation A and formulation B.

[0019] Figure 7 shows quantification of plant condition in rye grass treated with control (water), formulation A, formulation B or biostimulant product containing formulation A and formulation B.

[0020] Figure 8 shows quantification of plant condition in bluegrass treated with control (water), formulation A, formulation B or biostimulant product containing formulation A and formulation B.

[0021] Figure 9 shows quantification of root condition in bluegrass treated with control (water), formulation A, formulation B or biostimulant product containing formulation A and formulation B.

[0022] Figure 10 shows quantification of root condition in rye grass treated with control (water), formulation A, formulation B or biostimulant product containing formulation A and formulation B. Figure 11 shows soil microbial respiration rate following treatment of soil with control (water), formulation A, formulation B or biostimulant product containing formulation A and formulation B.

[0023] THE BIOSTIMULANT PRODUCT

[0024] A biostimulant product according to the invention comprises formulation B and formulation A as described herein. It is preferred that formulation B and formulation A additionally each comprise a liquid carrier, for example, an aqueous solution or water.

[0025] According to certain embodiments, formulation B and formulation A may be provided in the biostimulant product in separate containers. In such embodiments the biostimulant product of the invention comprises formulation A in a first container and formulation A in a second container. For example, a biostimulant product of the invention may comprise a formulation and formulation A in separate liquid carriers in separate containers for mixing before use (and optionally the biostimulant product may optionally additionally comprise instructions for mixing and / or additional outer packaging (for example, an outer box to contain the separate containers).

[0026] According to preferred alternative embodiments, the biostimulant product comprises formulation B and formulation A pre-mixed, for example, in a single liquid carrier and / or as a single container. Such a product may optionally additionally comprise instructions for use and / or additional outer packaging (for example, an outer box to contain the separate containers).

[0027] According to other embodiments of the biostimulant product according to the invention, the various components of formulation B and / or the various components of formulation A may optionally be provided in any number of separate containers. In such embodiments, the biostimulant product as a whole will contain each of the components or formulation b and each of the components of formulation A by virtue of the any number of separate containers being provided together in some additional outer packaging, for example, an outer box.

[0028] DERIVATIVES

[0029] Each of the specific components of formulation B and formulation A may optionally be provided as the specified compound or as a derivative of the specified compound. For example, where the specified compound is an acid such as vanillic acid it may be provided in the acid form or as a suitable salt form such as calcium vanillate or potassium vanillate. Other derivatives encompassed by the invention include ester forms (such as carboxylic ester forms). According to certain embodiments, derivatives of each of the components must retain at least 50% of an activity, in particular biostimulant activity, of the corresponding non-derivatized compound. Optionally, it may be preferred to provide a component of a formulation as a derivative for ease of formulation, stability, safety, compatibility or handing. For example, where the component is an acid, it may be preferred to provide that acid as a derivative which is a salt or ester form of that acid so that it may be provided at a preferred pH.

[0030] According to certain preferred embodiments, one or more of the specified compounds of formulation B and formulation A are the compounds specified or salt forms thereof. Suitable salt forms include sodium, potassium, magnesium, calcium, ammonium, and lithium salt forms.

[0031] In certain embodiments, the compounds are not derivatives of the specified compounds.

[0032] COMPONENTS OF FORMULATION B AND FORMULATION A

[0033] Vanillic acid (4-hydroxy-3-methodbenzoic acid) is a monohydroxybenzoic acid. It may be obtained from a variety of natural sources including extracted from Acai oil from Euterpe oleracea. It may also be synthesized artificially by oxidation of vanillin which in turn can be produced from lignin. In certain embodiments, the component is provided as a salt of vanillic acid.

[0034] Cinnamic acid (2E-3-phenylprop-2-enoic acid) is a monocarboxylic acid consisting of acrylic acid with a phenyl substitute at the 3-position. It is found in oil of cinnamon obtained from Cinnamomum cassia. It may also be prepared synthetically, for example, via the Perkin reaction. It exists as both a cis and trans isomer and according to the invention is present in either form or in certain embodiments as a mixture of both forms. In certain embodiments, the component is provided as a salt of cinnamic acid.

[0035] Dicaffeoylquinic acid (3,5-dicaffeoylquinic acid or (1 S,3R,4S,5R)-1 ,3,4,5-tetrahydroxy-1- carobxycyclohexane-3, 5-di-3-(3,4-dihydroxyphenyl propenoate) is a carboxylic ester. It can be isolated from propolis or Suaeda glauca. In certain embodiments, the component is provided as a salt of dicaffeoylquinic acid. Chloroqenic acid (1 S,3 , 4 ,5 )-3 {[(2E)-3-(3,4-dihydroxyphenyl) prop-2-enoyl]oxy}-1 ,4,5- trihydroxycyclohexane-1 -carboxylic acid) is a cinnamate ester and tannin and an intermediate metabolite in the biosynthesis of lignin. It is found in many plants including Phyllostachys edulis and Calluna vulagris. In certain embodiments, the component is provided as a salt of chlorogenic acid.

[0036] Coumarolyquinic acid (3-p-coumarolyquinic acid, 3-O-coumarolyquinic acid or 1 ,3 ,4S,5 )-1 ,3,4-trihydroxy-5-[E]-3-(4-hydroxyphenyl) prop-2-enoyl] oxycyclohexane-1- caroboxylic acid is a cinnamate ester present in many plants including cherry (Prunus avium, P. cerasus). In certain embodiments, the component is provided as a salt of coumarolyquinic acid.

[0037] Quercetin is a plant flavonoid found in many plants and foods. It exists in a number of glycoside forms including quercetin-3-O-rutinoside ((42S,43R,44S,45S,46R,72R,73R, 74R,75R,76S)-13,14,25,27,43,44,45,73,74,75-Decahydroxy-76-methyl-24H-3,6-dioxa- 2(2,3)-[1]benzopyrana-4(2,6),7(2)-bis(oxana)-1 (1)-benzenaheptaphane-24-one, also known as rutin), quercetin-3-O-galactoside (2-(3,4-Dihydroxyphenyl)-5,7-dihydroxy-3- {[(2S,3R,4S,5R,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy}-4H-1-benzopyran-4- one, also known as hyperoside) and quercetin-3-0-rhamnoside (2-(3,4-Dihydroxyphenyl)- 5,7-dihydroxy-3-{[(2S,3R,4R,5R,6S)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxy}-4H-1- benzopyran-4-one, also known as quercitrin and thujin). According to preferred embodiments, the one or more quercetin glycosides of formulation B are quercetin 3-0- galactoside, quercetin 3-0-rhaminoside and quercetin 3-0-rutinoside.

[0038] Syrinqic acid is a naturally occurring phenolic compound (4-hydroxy-3,5- dimdohyoxybenzoic acid). In certain embodiments, the component is provided as a salt of syringic acid.

[0039] Procyanidin dimers are a class of proanthocyanidins. They may be type A or type B dimers. According to certain preferred embodiments they are B type procyanidin dimers (also known as catechin dimers). It is preferred that the procyanidin dimer of formulation A is procyanidin B2 dimer (epicatechin-(4(i^8) epicatechin which is a proanthocyanin consisting of two molecules of (-)-epicatechin joined between positions 4’ and 8’ in a beta configuration. It can be found in the bark of many trees including Cinchona pubescens.

[0040] Procyanidin trimers are a class of proanthocyanidins. They may be type A or type B trimers. According to certain preferred embodiments the procyanidin trimer of formulation A is a type B trimer. More preferably, it is a procyanidin C2 trimer (catechin-(4a^8) catechin-(4a^8)-catechin trimer C2).

[0041] Kaempferol rahmnoside (also known as kaempferol-3-O-rhamnoside and 5,7-dihydroxy-2- (4"hydroxyphenyl)-3-(3,4,5-trihydroxy-6-methyloxan-2-yl)oxychromen-4-one) is a flavonoid glycoside.

[0042] Prodelphinidin dimer (also known as prodelphinidin B3, galloccatechin-(4a^8)-catechin and 2-(3,4-dihydroxyphenyl)-8-[3,5,7-trihydroxy-2-(3,4,5-trihydroxyphenyl)-3,4-dihydro-2H- chromen-4-yl]-3,4-dihydro-2H-chromene-3,5,7-triol is a proanthocyanidin consisting of three (+)-catechins joined by two 4a^8 linkages.

[0043] Gentisic acid is found in Alchornea cordifolia and is a dihydroxybenzoic acid also known as gentianic acid and 2,5-dihydroxybenzoic acid. In certain embodiments, the component is provided as a salt of gentisic acid.

[0044] A biostimulant product of the invention is preferably a liquid product. For example, an aqueous liquid product, with the components of formula B and the components of formula A present in a lipid carrier, for example an aqueous carrier as dissolved or suspended components. It may optionally be produced from one or more biostimulant stock composition, for example it may be produced from a biostimulant stock composition, for example by diluting the biostimulant stock composition, for example by adding water to the biostimulant stock composition. According to preferred embodiments, a liquid biostimulant product of the invention has the components present in each of formulation B and formulation A at the concentrations indicated below.

[0045] Formulation B components

[0046] Vanillic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0047] Cinnamic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml. Dicaffeoylquinic acid or a derivative thereof preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0048] Chlorogenic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0049] Coumaroylquinic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0050] Each of the one or more quercetin glycosides or derivates thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0051] In certain embodiments, the one or more quercetin glycosides or derivates thereof comprise: i, quercetin-3-O-galactoside or a derivative thereof which is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml. ii, quercetin-3-O-rhamnoside or a derivative thereof which is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml. iii, quercetin-D-rutinoside or a derivative thereof which is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml. Formulation A components

[0052] Vanillic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0053] Cinnamic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0054] Dicaffeoylquinic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0055] Chlorogenic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0056] Coumaroylquinic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0057] Each of the or more quercetin glycosides or derivates thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0058] Syringic acid or a derivative thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0059] Procyanidin dimer or a derivate thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml. Prodelphinidin dimer or a derivate thereof is preferably present at a concentration of between 0.05 and 5.0 mg / ml, for example between 0.1 and 2 mg / ml, for example between 0.2 and 1 mg / ml, for example between 0.2 and 0.8mg / ml, for example between 0.25 and 0.75mg / ml.

[0060] A liquid biostimulant stock composition typically has each component present at higher concentrations than those concentrations stated above, for example, at 10, 50, 100, 200 or 500 times as concentrated (optionally provided with instructions to dilute by that factor). According to certain embodiments, a biostimulant stock composition may comprise the components of formulation B or formulation A or formulation B and formulation A. That is to say that the biostimulant product may be prepared from two separate biostimulant stock compositions, one for formulation B and one for formulation A, or the biostimulant stock composition may comprise the components of both formulation B and formulation A such that a complete biostimulant product may be prepared from a single stock solution.

[0061] Further components

[0062] A biostimulant product or a biostimulant stock composition may optionally further comprise additional components, for example, surfactants, and / or preservatives. Preferably, a biostimulant product or a biostimulant stock composition according to the invention do not contain any phytotoxic components, or do not contain any components that are phytotoxic when at a dilution appropriate for application to plant.

[0063] PLANT GROWTH MEDIA

[0064] The invention also provides according to a further aspect plant growth media. Plant growth media may be soil, compost or any other plant growth medium, or a mixture of any thereof. It may be used to propagate plants in either alone, or when mixed with other plant media. Plant growth media according to the invention comprises the components of formulation B and the components of formulation A as defined above. According to certain embodiments, the components may be present at concentrations which correspond to one tenth, one hundredth or one thousandth, of the preferred concentrations given above in respect of a biostimulant product of the invention. Optionally, plant growth media of the invention may be prepared by applying a biostimulant product of the invention to a plant growth medium. METHODS OF THE INVENTION

[0065] Methods of preparation

[0066] According to a further aspect of the invention, there is provided a method of making a biostimulant product of the invention, by diluting a biostimulant stock composition of the invention, for example by a factor or at least 5, at least 10, at least 15, at least 20, at least 25 at least 30.

[0067] The biostimulant stock composition may be optionally diluted by a factor of no more than 500, not more than 400, no more than 300, no more than 200, no more than 150, or no more than 100.

[0068] The diluent is preferably aqueous. In certain embodiments it may be water, for example, tap water, borehole water, river water, lake water or harvested rainwater. It is preferably fresh water (not salty or brackish water). It will be appreciated that the water may be, but does not necessarily have to be, potable water.

[0069] According to a further aspect of the invention, there is provided a method of preparing a biostimulant product of the invention, or a biostimulant stock composition of the invention comprising the step of bringing together the components. According to certain embodiments, this bringing together of components may comprise the bringing together of components of formulation B with components of formulation A. Preferably the components are brought together in a single solution or suspension, for example in an aqueous carrier. Alternatively, they are brought together in more than one single solution or suspension, for example by being brought together in a outer packaging containing the more than one solution or suspension.

[0070] Methods of use

[0071] Accord to a further aspect of the invention, there is provided a method of treating an area comprising one or more plants and / or plant growth media, the method comprising applying to said area a biostimulant product of the invention. The one or more plants or plant growth media may optionally comprise, or be derived from, a monocotyledon, such as ryegrass, or a dicotyledon, such as lettuce. The method may comprise applying the biostimulant product to one or more plants or plant growth media, and / or to the substrate in which the one or more plants or plant growth media are located. In this case, the biostimulant product contacts the plants or plant growth media. The method may comprise applying the biostimulant product to plant growth media. This may be carried wherein there is a plant, for example a plant intended to benefit from the biostimulant product, present in the plant growth media. In alternative embodiments, the biostimulant product may be applied to the plant growth media prior to the plant intended to benefit from the biostimulant product being placed into the plant growth medium, for example prior to sowing of plant seeds or prior to the transplantation of plant seedlings.

[0072] The biostimulant product may be provided as a wash or spray, for example. In such embodiments, method of the invention may optionally include the step of washing or spraying one or more plants or washing or spraying plant prorogation material. The method may comprise applying biostimulant product to individual growth receptacles, containers or pots. Alternative it may comprise applying biostimulant product to an open or enclosed field, lawn or sports pitch.

[0073] The method may comprise adding the biostimulant stock composition of the invention to an irrigation supply or soil drench.

[0074] The method may comprise applying from 0.1 to 200 ml of the biostimulant product of the present invention per hectare of the area, for example between 0.2 and 100 ml per hectare, for example between 0.5 and 75 ml per hectare, for example between 1 and 50 ml per hectare, for example between 2 and 20 ml per hectare. According to certain embodiments, the total polyphenol applied is below 5 mg per hectare, for example below 2 mg per hectare, for example below 1mg per hectare. It may be, for example, between 0.1 and 5 mg per hectare, between 0.2 and 2 mg per hectare, or between 0.3 and 1.5 mg per hectare.

[0075] The method may comprise applying a biostimulant product in accordance with the present invention at least once every three years, optionally at least once every two years, optionally at least once every year, optionally at least once every nine months, optionally at least once every six months, optionally at least once every four months, optionally at least once every three months, optionally at least once every two months, optionally at least once a month and optionally more than once per month. It will be understood that for short-lived crops, such as salad vegetables, the frequency of application may be better expressed as applications per crop. Accordingly, the method may comprise applying a biostimulant product in accordance with the present invention once, twice or three times in the interval between planting and harvesting the crop. It will, of course, be appreciated that features described in relation to one aspect of the present invention may be incorporated into other aspects of the present invention.

[0076] According to certain embodiments of the invention, there are provided methods of increasing leaf biomass, methods of improving plant health and condition and methods of improving root development. Such improvements may optionally be mediated via increases in soil respiration (i.e., increases in the respiration rate of the soil microbiome). The invention may also provide methods of improving plant drought resistance and methods of improving crop yield. In all these methods, the plant may be a crop plant, for example a salad vegetable, a culinary herb or spice, a cereal, a root vegetable or a fruit or nut. In other embodiments the plant day be an ornamental plant, for example an ornamental houseplant or ornamental garden plant. In other embodiments of the invention, the plant may be a grass, for example a pasture grass, a silage grass or a meadow grass. In certain embodiments, the grass is a ryegrass for example. In certain embodiments the grass may be a lawn or the grass of a sports pitch or other sporting surface, for example a golf course or tennis court. In other embodiments the plant may be a soft fruit crop plant. A method of increasing leaf biomass, a method of improving plant health and condition, a method of improving root development, a method of improving plant drought resistance and a method of improving crop yield may comprise the step of comprise applying a biostimulant product in accordance with the present invention, and optionally having one or more additional compositional or application features as described herein.

[0077] According to certain embodiments of the invention, there are provided methods of increasing the respiration rate of a soil microbiome.

[0078] Preparation of biostimulant products and stock compositions

[0079] The components of formulation B and formulation A of biostimulant products of the invention and of biostimulant stock compositions of the invention, may be prepared from any suitable material. Because many of the components are present in plant material, the biostimulant product of the invention and the biostimulant stock composition of the invention, may optionally be prepared from suitable plant material. Because plant material may contain more than one of the components of formulation B or more than one of the components of formulation A, the use of plant material for preparing the biostimulant product of the invention or the biostimulant stock composition of the invention may usefully simplify the method of preparation. Method of improving health of plant growth media

[0080] The invention also provides a method of improving the health of plant growth media, for example a method of improving soil health comprising applying a biostimulant product of the invention, optionally further comprising one or more additional compositional or application features as described above to the plant growth media, for example to soil or compost.

[0081] Preferably, this method increases the microbial activity of the plant growth medium, for example it may increase the respiration rate of microbes in the plant growth medium. Respiration rate can be measures by detecting the rate of carbon dioxide production or the rate of oxygen consumption in a sample of plant growth medium.

[0082] Embodiments of the present invention will now be described by way of the following Examples.

[0083] EXAMPLES

[0084] MATERIALS AND METHODS

[0085] Preparation of biostimulant products

[0086] Formulation B containing vanillic acid, cinnamic acid, dicaffeoylguinic acid, chlorogenic acid, coumaroylguinic acid, caffeoylguinic acid, guercetin 3-0 galactoside, guercetin 3-0 rhamnoside, guercetin 3-0 rutinoside kaempferol rahmnoside, gentisic acid and procyanidin trimer were prepared with each component present at approximately 0.46 mg / ml and a total polyphenol level of approximately 0.06 mg / ml.

[0087] Formulation A containing vanillic acid, cinnamic acid, dicaffeoylguinic acid, chlorogenic acid, coumaroylguinic acid, syringic acid, procyanidin dimer, and prodelphinidin dimer were prepared with each component present at approximately 0.46 mg / ml and a total polyphenol level of approximately 6.87 mg / ml.

[0088] A biostimulant product comprising formulation B and formulation A was prepared by mixing egual volumes of formulation B and formulation A. EXAMPLE 1 : effect of product on plants

[0089] Plants to be tested

[0090] Rye grass (Lolium perenne), Kentucky bluegrass (Poa pratensis) and thale cress (Arabidopsis thaliana), were sown in compost in individual pots.

[0091] Testing of products

[0092] Formulation B, formulation A or a biostimulant product comprising both formulation B and formulation A was applied and mixed in equal volumes to the pots of plants at sowing and at day 7 and 14. No treatment controls were also used.

[0093] Sampling of plants

[0094] Rye grass, and thale cress was harvested at day 28, and bluegrass, which took longer to grown at day 43.

[0095] Leaf biomass, root development and plant condition was assessed for each of the grasses. For the thale cress, RNA was extracted and quantified to assess gene expression. Leaf biomass was weighed and plant condition and root development were scored on a scale 1 to 10. Statistical analysis was carried out using GraphPad 9 to 95% confidence levels.

[0096] RESULTS

[0097] Plant growth and condition.

[0098] As can be seen in figures 1 to 10, in both species tested, compared to the no treatment (water) control, treatment with formulation A showed an improvement in overall plant condition, in root development and leaf biomass. However, the addition of formulation B to a biostimulant product containing both formulation A and formulation B produced significantly greater improvement, suggesting an advantage of such a product over the use of a single formulation, A or B on its own Because the biostimulant product comprising both formulation B and formulation A was prepared by mixing formulation A and formulation B together such that the combined “B + A” product contained half the quantity of formulation B and formulation A as the single formulation products, advantages of “B + A” can be attributed to the combination of components and not simply an overall increase in biostimulant products. RNA

[0099] In order to investigate possible mechanisms of biostimulation of a product of the invention, gene expression was measured in Arabidopsis thaliana following treatment with either formulation A on its own or with a biostimulus product comprising a mixture of equal parts of formulation A and formulation B.

[0100] Formulation A on its own induced upregulation of the six genes listed below:

[0101] Treatment with a product comprising formulation A and formulation B resulted in the upregulation of 132 genes as listed below:

[0102] EXAMPLE 2: effect of product on soil microbial respiration Testing of products

[0103] 20 ml of formulation B, formulation A or 20ml of a biostimulant product comprising 10 ml of formulation B and 10 ml of formulation A was applied to 300g of soil and the effect on respiration of soil microbes assessed by measuring CO2 levels resulting.

[0104] RESULTS

[0105] Measured respiration rates are shown in the table below and in table 11. It can be seen that both formulation A and formulation B result in an increase in respiration compared to the water control. However, the greatest effect is shown from a product containing formulation A and formulation B, suggesting that their a synergistic effect of such a product.

Claims

CLAIMS1. A biostimulant product comprising: formulation A and formulation B, wherein formulation B comprises: vanillic acid or a derivative thereof, cinnamic acid or a derivative thereof, dicaffeoylquinic acid or a derivative thereof, coumaroylquinic acid or a derivative thereof, caffeoylquinic acid or a derivative thereof, one or more quercetin glycosides, or one or more derivatives thereof, kaempferol rhamnoside or a derivative thereof, gentisic acid or a derivative thereof, and procyanidin trimer or a derivative thereof; and wherein formulation A comprises: vanillic acid or a derivative thereof, cinnamic acid or a derivate thereof, decaffeoylquinic acid or a derivative thereof, chlorogenic acid or a derivative thereof, coumaroylquinic acid or a derivative thereof, syringic acid or a derivative thereof, procyanidin dimers or a derivative thereof, and prodelphinidin dimers or a derivative thereof.

2. A biostimulant product according to claim 1, further comprising a liquid carrier, for example, an aqueous solution or water.

3. A biostimulant product according to claim 1 or claim 2, wherein formulation B and formulation A are provided in separate containers and the biostimulant product further comprises additional outer packaging (for example, an outer box containing the separate containers).

4. A biostimulant product according to claim 1 or claim 2, wherein formulation B and formulation A are provided mixed in a single container.

5. A biostimulant product according to any of claims 1 to 4, wherein the one or more quercetin glycosides of formulation B are quercetin 3-O-galactoside, quercetin 3- O-rhaminoside and quercetin 3-O-rutinoside.

6. A biostimulant product according to any of claims 1 to 5, wherein the procyanidin dimers are B type procyanidin dimers (also known as catechin dimers).

7. A biostimulant product of according to claim 6, wherein the procyanidin dimer of formulation A is procyanidin B2 dimer (epicatechin-(4(i^8) epicatechin)8. A biostimulant product according to any of claims 1 to 7, wherein the procyanidin trimers are type B trimers.

9. A biostimulant product according to claim 8, wherein the procyanidin trimer of formulation A is procyanidin C2 trimer (catechin-(4a^8) catechin-(4a^8)-catechin trimer C2).

10. A biostimulant stock composition comprising formulation B and formulation A11. A biostimulant stock composition according to claim 10, further comprising a liquid carrier, for example, an aqueous solution or water.

12. A biostimulant stock composition according to claim 10 or claim 11 , wherein formulation B and formulation A are provided in separate containers and the biostimulant product further comprises additional outer packaging (for example, an outer box containing the separate containers).

13. A biostimulant stock composition according to claim 10 or claim 11 , wherein formulation B and formulation A are provided mixed in a single container.

14. A biostimulant stock composition according to any of claims 10 to 13, wherein the one or more quercetin glycosides of formulation B are quercetin 3-O-galactoside, quercetin 3-O-rhaminoside and quercetin 3-O-rutinoside.

15. A biostimulant stock composition according to any of claims 10 to 14, wherein the procyanidin dimers are B type procyanidin dimers (also known as catechin dimers).

16. A biostimulant stock composition according to claim 15, wherein the procyanidin dimer of formulation A is procyanidin B2 dimer (epicatechin-(48>^8) epicatechin)17. A biostimulant stock composition according to any of claims 10 to 16, wherein the procyanidin trimers are type B trimers.

18. A biostimulant stock composition according to claim 17, wherein the procyanidin trimer of formulation A is procyanidin C2 trimer (catechin-(4a^8) catechin-(4a^8)- catechin trimer C2).

19. A biostimulant product according to any of claims 1 to 9, or a biostimulant stock composition according to any of claims 10 to 18 further comprising one or more surfactants, and / or one or more preservatives.

20. A plant growth medium comprises the components of formulation B and the components of formulation A wherein formulation B comprises: vanillic acid or a derivative thereof, cinnamic acid or a derivative thereof, dicaffeoylquinic acid or a derivative thereof, coumaroylquinic acid or a derivative thereof, caffeoylquinic acid or a derivative thereof, one or more quercetin glycosides, or one or more derivatives thereof, kaempferol rhamnoside or a derivative thereof, gentisic acid or a derivative thereof, and procyanidin trimer or a derivative thereof; and wherein formulation A comprises: vanillic acid or a derivative thereof, cinnamic acid or a derivate thereof, decaffeoylquinic acid or a derivative thereof, chlorogenic acid or a derivative thereof, coumaroylquinic acid or a derivative thereof, syringic acid or a derivative thereof, procyanidin dimers or a derivative thereof, and prodelphinidin dimers or a derivative thereof.

21. A plant growth medium according to claim 10, which is or which comprises soil.

22. A plant growth medium according to claim 10, which is or which comprises compost23. A plant growth medium according to any of claims 20 to 22, wherein the one or more quercetin glycosides of formulation B are quercetin 3-O-galactoside, quercetin 3-O-rhaminoside and quercetin 3-O-rutinoside.

24. A plant growth medium according to any of claims 20 to 23, wherein the procyanidin dimers are B type procyanidin dimers (also known as catechin dimers).

25. A plant growth medium according to claim 24, wherein the procyanidin dimer of formulation A is procyanidin B2 dimer (epicatechin-(4(i^8) epicatechin)26. A plant growth medium according to any of claims 20 to 25, wherein the procyanidin trimers are type B trimers.

27. A plant growth medium according to claim 26, wherein the procyanidin trimer of formulation A is procyanidin C2 trimer (catechin-(4a^8) catechin-(4a^8)-catechin trimer C2).

28. A method of making a biostimulant product according to any of claims 1 to 9, by diluting a biostimulant stock composition of any of claims 10 to 19, by a factor or at least 5, at least 10, at least 15, at least 20, at least 25 at least 30.

29. A method of making a biostimulant product according to any of claims 1 to 9, by diluting a biostimulant stock composition of any of claims 10 to 19, by a factor of no more than 500, not more than 400, no more than 300, no more than 200, no more than 150, or no more than 100.

30. A method of claim 28 or claim 29, wherein the diluent comprises water.

31. A method of making a biostimulant product of any of claims 1 to 9, or a biostimulant stock composition according to any of claims 10 to 19 comprising the step of bringing together the components of formulation B with components of formulation A in a single solution or suspension, for example in a single aqueous carrier.

32. A method of treating an area comprising one or more plants and / or plant growth media, the method comprising applying to said area a biostimulant product of the invention.

33. A method according to claim 32 wherein the one or more plants or plant growth media comprise, a monocotyledon, such as ryegrass,34. A method according to claim 32 wherein the one or more plants or plant growth media comprise a dicotyledon, such as lettuce.

35. A method according to any of claims 32 to 34 comprising applying the biostimulant product to plant growth media, for example prior to sowing of plant seeds or prior to the transplantation of plant seedlings.

36. A method according to any of claims 32 to 35 comprising applying the biostimulant product as a wash or spray, for example by washing or spraying the one or more plants or washing or spraying the plant prorogation material.

37. A method according to any of claims 32 to 36 wherein the area comprising one or more plants and / or plant growth media is an open or enclosed field, lawn or sports ground (for example football pitch, tennis court or golf course).

38. A method according to any of claims 32 to 36 comprising adding a biostimulant stock composition as claimed in any of claims 10 to 19 to an irrigation supply or soil drench.

39. A method according to any of claims 32 to 37 wherein the biostimulant product is applied at least once every three years, optionally at least once every two years, optionally at least once every year, optionally at least once every nine months, optionally at least once every six months, optionally at least once every four months, optionally at least once every three months, optionally at least once every two months, optionally at least once a month and optionally more than once per month.

40. A method of increasing leaf biomass, a method of improving plant health or condition, a method of improving root development, a method of improving plant drought resistance or a method of improving crop yield comprising a method of applying a biostimulant product according to any of claims 32 to 39.

41. A method according to any of claims 32 to 40, wherein the one or more plants and / or plant growth media comprise a crop plant, for example a salad vegetable, a culinary herb or spice, a cereal, a root vegetable or a fruit or nut, an ornamental plant, for example an ornamental houseplant or ornamental garden plant, or a grass, for example a pasture grass, a silage grass, a meadow grass, a ryegrass, or a grass which is a lawn or the grass of a sports pitch or other sporting surface, for example a golf course or tennis court.

42. A method according to any of claims 32 to 41, wherein the method results in an increase of plant leaf growth by at least 30% by weight, compared with corresponding plants.

43. A method according to any of claims 32 to 41, wherein the method results in an increase of plant root growth by at least 30% by weight, compared with corresponding plants.

44. A method of improving the microbial health of plant growth media, for example a method of improving soil health comprising applying a biostimulant product according to any of claims 10 to 19, optionally in accordance with a method of any of claims 32 to 43, comprising application of a biostimulant product according to any of claims 1 to 9 to a plant growth medium, for example to a soil or compost.

45. A method according to claim 44 which increases the microbial activity of the plant growth medium, for example it may increase the respiration rate of microbes in the plant growth medium, by a factor of at least 2 or at least 4, compared to the respiration rate of microbes in the plant growth medium prior to the application of the biostimulant product.

46. Respiration rate can be measured by detecting the rate of carbon dioxide production or the rate of oxygen consumption in a sample of plant growth medium.

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