EP3687292A1

EP3687292A1 - New sap-compatible formulation

Info

Publication number: EP3687292A1
Application number: EP18786047.3A
Authority: EP
Inventors: Eliana Rita SOLORZANO; Elisa DAL MASO; Paolo Pastore; Lucio MONTECCHIO; Marco Frasconi; Sara BOGIALLI
Original assignee: Piante Acqua Natura Srl PAN
Current assignee: Newpharm SRL
Priority date: 2017-09-29
Filing date: 2018-09-27
Publication date: 2020-08-05
Also published as: WO2019064219A1; IT201700109583A1

Abstract

The present invention relates to a new sap-compatible formulation for the carrying of active ingredients injectable into the vascular system of woody plants or plants, methods of treatment of plants by injection of said formulation, kit for the treatment of plants comprising said formulation.

Description

"NEW SAP-COMPATIBLE FORMULATION"

DESCRIPTION

The present invention relates to a new sap-compatible formulation for the carrying of active ingredients (principles) injectable into the vascular system of plants, methods of treatment of plants by injection of said formulation, kit for the treatment of plants comprising said formulation.

STATE OF THE PRIOR ART

The distribution of plant protection products to tree crops of agronomical, forest and ornamental interest is a process still exhibiting well-known critical issues, such as, e.g., non-complete selectivity of the active ingredient toward the target parasite, non-homogeneous in-plant distribution, toxicity to the operator, as well as frequent phenomena of accumulation and pollution in the ecosystem.

In vascular plants, xylem sap rises from roots to leaves along sap vessels. By exploiting said mechanism, fluids (e.g., pesticides, fungicides, bactericides, fertilizers, desiccants) compatible with the chemico-physical characteristics of sap can be injected in the xylem system and transported passively in the entire plant (Montecchio L, 2013. A Venturi effect can help cure our trees. Journal of Visualized Experiments 80, 51199. doi: 10.3791/51 199 Montecchio L, 2013. A Venturi effect can help cure our trees. Journal of Visualized Experiments 80, 51199. doi: 10.3791/51199; Liang N., Lili T., 2016. Special nutrient solution for preventing and controlling peach tree yellowing and preparation and application thereof. CN 105732197 (A); Yonggang M., Zhonggui S., Jiangning Z., Zhongwei Y., Futang L. et al., 2015. Full-effect tree nutrition infusion liquid. CN104649814 (A); Jiulan H., 2017. Injection nutritional liquid for fruit trees. CN106892705 (A)). This method is known as endotherapy. Among the most significant aims that can reasonably be reached with the endotherapeutical approach, there may be mentioned:

1) reduction of the amount of plant protection products to be used, and of that dispersed in the environment;

2) targeted carrying of the plant protection product;

3) reduction of exposure to phytosanitary product residues in the environment of non-target organisms;

4) preservation of soil, waste water and air from contamination;

5) safer use for operators;

6) option of carrying out the treatments under windy conditions;

7) increase of the effectiveness of a single treatment, even up to 24 months. Said aspects comply with the contents of Directive 2009/128/EC, legislative decree n.150/2012 and the current National Action Plan for the sustainable use of phytosanitary products.

The greatest obstacle in the use of the endotherapeutical technique consists in the scarce presence on the market of formulations studied for the purpose. In Italy, in comparison with 329 active ingredients employed for traditional sprinkling, those employed also or exclusively for endotherapy are six (Azadirachtin, Chlorpyrifos- methyl, Imidacloprid, Abamectin, potassium phosphites and Glyphosate), for all of which the sole carrier prescribed by the producing company is water. The potentials of carriers for endotherapy different from water and capable of enabling the injection of non-soluble active ingredients, or to speed up those already sufficiently soluble, have been investigated for many years, but the greatest efforts were addressed to the use of protic (alcoholic) and aprotic (acetone, dimethyl sulfoxide) polar alcoholic organic solvents, of difficult practical use and with an inherent toxicity for plant and operator. E.g., Takai K., Soejima T., Suzuki T., Kawazu, K., 2001 , Pest Management Science 54, 463-466. doi: 10.1002/ps.301 , describes the development of a water-soluble preparation of emamectin benzoate and its use in-plant, but also reports phenomena of chromatic alteration and cambium necrosis caused by the solvents used. In 2014, Dal Maso E., Cocking J., Montecchio L, 2014, Urban Forestry & Urban Greening 13, 697-703. doi: 10.1016/j.ufug.2014.07.005, tested the use of acids (e.g., acetic acid) or salts (e.g., ammonium nitrate) to speed up injection on European Ash (fraxinus excelsius), but such formulations did not prove applicable with a wide range of active ingredients and plant species (personal communication).

In the actual state of the art, the factors that most limit the use of endotherapy are:

- nil or very slow injectability (due to incompatibility with sap) of many authorized phytosanitary products

- phytotoxicity to the plant and/or toxicity to the operator of some solvents tested/used in the past or employed to date in numerous Countries (e.g., acetone, acetonitrile, dioxane, dipropylene glycol, hexanol, ethanol, methanol, methyl ethyl ketone, tetrahydrofuran)

- in case of slow injectability, the need to force the injection by high-pressure applications to speed up the process. Such a methodology can cause considerable damage to the plant (e.g., embolism and/or bark detachment); moreover, said technique is usually more expensive and requires greater skill by the operator, also to avoid counterproductive spills and leakages of solution to be injected. SUMMARY OF THE INVENTION

The Authors of the present invention have made an innovative formulation compatible with plant sap, suitable for solubilising commercial products and active ingredients registered for endotherapy, both lipophilic and hydrophilic ones, exhibiting the following peculiarities:

- compatibility with the chemico-physical characteristics of sap;

- at the concentration of administration, full solubility with many water-mixable commercial phytosanitary products currently registered for endotherapy;

- absence of phytotoxicity at the doses of use;

- increase of injection rate as compared to solvents used to date (e.g., water)

- possibility of injecting the sole formulation as agent having a chelating, anti- oxidising and anti-scorching effect.

The Authors of the present invention have discovered that the use of carboxylic acids in combination with potassium chloride, at appropriate concentrations of use, significantly improves the effectiveness of diffusion of the carrier and of any phytotherapeutic product dissolved therein into sap vessels. Moreover, the combination made by the Inventors significantly speeds up absorption by the sap of commercial products, both hydrosoluble and liposoluble ones, already authorized for endotherapeutical applications.

Therefore, the Authors have made a formulation, non-phytotoxic at the doses of use, capable of carrying in the sap flow of woody plants and palms active ingredients usually absorbed very slowly when dissolved in the solvents commonly used in endotherapy practice (e.g., water, glycol ethers).

Therefore, object of the invention are a mixture comprising at least one carboxylic acid and at least one potassium chloride in the appropriate proportions, as defined in the detailed description and in the claims, a liquid formulate in concentrated and non-concentrated form comprising said mixture, a phytopharmaceutical carrier comprising said mixture, a phytopharmaceutical composition comprising said mixture or carrier and optionally one or more phytopharmaceutical active ingredients, the use of said mixture or of said carrier for the preparation of said composition, the use of said mixture, or of said formulate, or of said carrier for the treatment of woody plants and palms by injection into the vascular system of said plants (e.g. by BITE, "blade for infusion in trees", as defined above), a therapeutic method for the treatment of woody plants or palms comprising at least one step wherein a phytopharmaceutical composition comprising a mixture or a formulate as defined below or in any one of the claims, a carrier as defined below or in any one of the claims, and optionally one or more phytopharmaceutical active ingredients, is injected into the vascular system of said plants. DETAILED DESCRIPTION OF THE FIGURES

Figure 1. In the graph, histograms indicate the average injection rate for each solution, with the related standard error.

* The absorption rate depends on physiological and environmental variables (e.g., phenological state, soil moisture, solar irradiation, windiness).

Figure 2. In the graph, histograms indicate the average injection rate for each solution, with the related standard error; the pH is indicated with orange-coloured dots.

* As already indicated for example 1 , the absorption rate depends on physiological and environmental variables (e.g., phenological state, soil moisture, solar irradiation, windiness).

Figure 3. In the graph, histograms indicate the average injection rate for each solution, with the related standard error.

The figure shows how the combination between carboxylic acid and potassium chloride significantly increases the hydraulic mobility of the mixture.

* As already indicated for examples 1 and 2, the absorption rate can vary depending on physiological and environmental variables (e.g., phenological state, soil moisture, solar irradiation, windiness).

Figure 4. In the graph, the histogram of the average injection rate for each solution, with relative standard error.

The figure shows how the combination of carboxylic acids with potassium chloride significantly increases the hydraulic mobility of the mixture.

* As already indicated for the examples 1 and 2 and 3, the speed of absorption can vary according to physiological and environmental variables (phenological status, soil moisture, absolution, windiness).

Thus, owing to the above-reported reasons, the results reported in the figures of examples 1 , 2, 3 and 4 cannot be compared, but must be referred to the relative control in the same figure (demineralized water).

DETAILED DESCRIPTION OF THE INVENTION

The present description relates to a mixture consisting of one or more inorganic acids or one or more carboxylic acids, or a combination thereof at a total weight/weight concentration of 20 to 60% and one or more potassium chloride at a total weight/weight concentration of 80 to 40% of said mixture, optionally in combination with one or more phytopharmacologically acceptable active ingredient, compositions comprising said mixture, uses thereof and methods for the treatment of plants comprising the endotherapeutical administration of said compositions or of said mixture. The mixture according to the present description can therefore be a solid-state mixture in the form of powders, tablets, granulates, crystals, capsules wherein said solid-state mixture is soluble in suitable solvents as defined hereinafter.

In particular, as better described hereinafter, the mixture according to the present description can appear in a solid state, e.g. as a soluble powder (SP), or liquid, for instance as a soluble concentrated formulate (SL), in accordance with FAO (Food and Agricultural Organization of the United Nations) international denomination, depending on the end application. Such a mixture could then be appropriately diluted into phytopharmaceutically acceptable substances for endotherapeutical use in the plant. Such use may be for therapeutic purposes or to prevent plant diseases.

In the present description, the term "concentrated liquid formulate" is used to define the soluble concentrate as described above. The skilled person is well aware that mixtures in a solid state are often suspended in a concentrated form (commonly defined also as stock solutions or soluble concentrate, concentrated liquid formulate in the present description) that will subsequently be diluted into the working concentration, depending on the selected protocol. Therefore, concentrated liquid formulate is used herein to define the stock solution, or soluble concentrate, that will be further diluted by the operator before use.

The concentrated liquid formulate is, in fact, defined in terms of a weight/volume ratio, i.e. the weight of mixture in solid-state/the volume of the solvent, whereas the further dilution thereof herein also simply defined as "liquid formulate" as opposed to "concentrated liquid formulate" (i.e. the working solution) is defined in terms of volume/volume, i.e. the volume of concentrated liquid formulate (stock solution, or SL)/the volume of the solvent.

In any part of the description and of the claims, all the liquid formulates or mixtures whose composition is expressed in weight/volume terms fall in the definition of "concentrated liquid formulate" or stock solution or SL.

All the liquid formulates or mixtures expressed in volume/volume terms fall into the definition of "dilution of the concentrated liquid formulate", working solutions or, more simply, "liquid formulates".

According to the present description, said one or more carboxylic acids are monocarboxylic, dicarboxylic, tricarboxylic and/or polycarboxylic acids.

According to one embodiment, said acids are aliphatic saturated or unsaturated organic acids with linear or branched or cyclic C1-C16 carbon chains, including aromatic acids.

In specific embodiments, said acids can be (without limitation) acetic acid, propionic acid, butyric acid, capric acid, caprylic acid, glutaric acid, succinic acid, tartaric acid, fumaric acid, maleic acid, adipic acid, citric acid, salicylic acid, caffeic acid, benzoic acid, cynnamic acid, optionally substituted with amino, carbonyl and/or hydroxyl groups; and inorganic acids, such as boric acid, hydrochloric acid.

According to one embodiment, always without limitation, said substituted acids may be selected, e.g., among aspartic acid, malic acid, glutamic acid, p-cumaric acid. The acids according to the invention are preferably organic aliphatic ones, with Carbon (C) chains of 3 to 16 C units, be them of simple linear or branched or cyclic chain, saturated, or, in case, water-soluble unsaturated ones, and non-phytotoxic at the concentrations assayed. Aromatic carboxylic acids can also be considered. Some non-limiting examples of said acids are reported in Table 1.

Table 1 : Examples of acids useful in the solid- or liquid-state mixture

In the SP form, said acids will be used in the solid state.

As mentioned above, said acids could be optionally substituted, e.g. aromatic and aliphatic acids with amino (-NH2), carbonyl (C=0), and/or hydroxyl (OH) substituents could be used. Some non-limiting examples of such substituted acids may be *succinic acid with amino substituent (aspartic acid) or with hydroxyl substituent (malic acid); glutaric acid with amino substituent (glutamic acid); cynnamic acid with hydroxyl substituent (p-cumaric).

In one embodiment, also inorganic acids at non-phytotoxic concentrations can be used. Non-limiting examples of the latter can be represented by boric acid, hydrochloric acid.

Potassium chloride is advantageously comprised in the mixture, since potassium increases, as shown in Figure 3, hydraulic mobility inside xylem vessels, increases anti-oxidizing abilities in the plant and enhances plant resistance to biotic (phytopathogenic microorganisms) and abiotic (drought, excessive exposure to light, etc) stress, and finally, since potassium concentration in the apoplast is usually low, potassium ion tends to accumulate in vacuoles, and, along with chloride ion, increases their osmotic potential. This fact induces stomatal closure post- application, avoiding possible embolisms and fostering plant resistance against hydric stress.

The description also relates to a liquid formulate (concentrate) comprising from 0.2 to 10% by weight/volume of the solid mixture according to any one of claims or according to any one of the above-described embodiments, and at least one phytopharmacologically acceptable solvent.

In one embodiment, the concentrated liquid formulate comprises from 1 to 2% by weight/volume of the solid mixture according to any one of the claims, or according to any one of the above-described embodiments, and at least one phytopharmacologically acceptable solvent.

In one preferred embodiment, the concentrated liquid formulate comprises from 1.5 to 1.7 % by weight/volume of the solid mixture according to any one of claims or according to any one of the above-described embodiments, and at least one phytopharmacologically acceptable solvent.

In one particularly preferred embodiment, the concentrated liquid formulate comprises about 1.61 % by weight/volume of the solid mixture according to any one of claims or according to any one of the above-described embodiments, and at least one phytopharmacologically acceptable solvent.

In other terms, the concentrated liquid formulate may comprise from 0.04 to 4 g of carboxyl acid(s) per 100 ml of said formulate and from 0.12 to 8 g of potassium chloride per 100 ml of said formulate.

For instance, the concentrated liquid formulatemay comprise from 0.2 to 0.8 g of carboxyl acid(s) per 100 ml of said formulate and from 0.6 to 1.6 g of potassium chloride per 100 ml of said formulate.

In one preferred embodiment, the concentrated liquid formulate may comprise from 0.3 to 0.68 g of carboxyl acid(s) per 100 ml of said formulate and from 0.9 to 1.36 g of potassium chloride per 100 ml of said formulate.

In case the concentrated liquid formulate comprises about 1.61 % by weight/volume of the solid mixture as defined above, this corresponds to about 0.55 g of carboxylic acid per 100 ml of said formulate and about 1.06 g of potassium chloride in case the acid is citric acid and the solid mixture is composed by 34.01 % citric acid and 65,99 % potassium chloride.

According to the present description, the solvent could be water, or an aqueous solution of water-miscible solvents, an aqueous solution of water-soluble active ingredients, an aqueous solution of formulations of water-miscible active ingredients. Non-limiting examples of water-miscible solvents suitable for the making of the formulates according to the invention may be:

aqueous solutions containing propanol, glycerol, propylene glycol, ethanol, methanol, dimethyl sulfoxide.

Non-limiting examples di aqueous solutions of water-soluble active ingredients suitable for the making of the formulates according to the invention may be:

aqueous solutions of active ingredients used in endotherapy, such as potassium phosphite.

Aqueous solutions of active ingredients, such as salicylic acid.

Non-limiting examples of aqueous solutions of formulations of water-miscible active ingredients suitable for the making of the formulates according to the invention may be:

Solutions of commercial formulations of the type Vertimec EC (abamectin), Imidachem and Confidor (Imidacloprid), Tecto 20S (thiabendazole)

According to a further embodiment, the concentrated formulate in liquid form as described herein could be further diluted, until comprising from 5 to 50% by volume/volume of the concentrated formulate as defined above, and at least one phytopharmacologically acceptable solvent.

The formulations or pure active ingredients combinable with the mixture, the formulates or the carrier according to the claims or according to the present description are all those employed in endotherapy having an activity on vascular plants, such as antiparasitic (e.g., abamectin), insecticide (e.g., azadirachtin, clorpirifos, imidacloprid), fertilizing (e.g., potassium phosphite), growth-retarding (e.g., salicylic acid) activities, or active ingredients, such as desiccants (e.g., glyphosate), or other purposes adopted in endotherapy. The formulations or pure active ingredients combinable with the present invention could be natural or synthetic products.

The mixture, the formulates or the carrier of the invention could be used effectively to carry active ingredients of difficult solubilization for non-endotherapeutical use. As defined above, said solvent could be water, or an aqueous solution of water- miscible solvents, an aqueous solution of water-soluble active ingredients, an aqueous solution of formulations of water-miscible active ingredients.

In short, the liquid formulate according to the present invention could be in the form of soluble concentrate (SL), herein "concentrated liquid formulate" or in a form suitable to be injected in-plant (WS - working solution), herein "liquid formulate", and will comprise:

1) mono-, di-, tri-carboxylic, polycarboxylic acids as above-defined, with a final concentration in the range of 0.01 M - solubility limit at room environment;

2) potassium chloride, with a final concentration in the range of 0.01 M - solubility limit at room environment.

According to the invention, the liquid formulate will have, at concentrations suitable for in-plant injection, a final pH not higher than 6, like, e.g., a final pH of 2 to 5.

In case of a liquid appearance, the addition of any emulsifiers, preferably non-ionic ones, and phytopharmaceutically acceptable antioxidants, useful for the specific application and/or preservation, may be considered for the formulation.

The formulation of the carrier is not suitable for dissolution/dilution in buffered formulations with a pH higher than 6, or with formulations containing iron salt concentrations higher than 5 mM.

Therefore, the present description also relates to a carrier comprised of the mixture according to any one of claims 1 to 5 or according to any one of the embodiments herein described, and at least one phytopharmacologically acceptable excipient and/or solvent, wherein said acids have a final concentration of 0.12 to 0.34 % by weight/volume and potassium chloride have a final concentration of 0.46 to 0.23% by weight/volume wherein said carrier is injectable into the vascular system of woody plants and palms.

Moreover, the carrier as defined herein could also comprise one or more phytopharmacologically acceptable active ingredients.

In accordance with the foregoing, the carrier described herein is characterised in that it has a pH not greater than 6, such as, e.g., a final pH of 2 to 5.

Non-limiting examples of the mixture or of the formulates according to the present invention are provided hereinafter.

Example 1 of solid mixture:

Citric acid 23.7 % (w/w)

Potassium chloride 47.0 % (w/w)

Adipic acid 5.8 % (w/w) Ascorbic acid 23.5 % (w/w)

Example 2 of solid mixture:

Citric acid 23.2 % (w/w)

Potassium chloride 47.0 % (w/w)

Succinic acid 17.4 % (w/w)

Ascorbic acid 1 1.2 % (w/w)

Gallic acid 1.2 % (w/w)

Example 1 of concentrated liquid formulate:

Citric acid 0.57 g

Sorbic acid 0.045 g

Potassium chloride 1.14 g

Dimethyl sulfoxide 1.15 ml

Lactic acid 0.3 ml

Water (qsp)* 100 ml

*qsp=quantity sufficient to reach a total volume of 100ml Example 2 of concentrated liquid formulate:

Citric acid 0.570 g

Sorbic acid 0.045 g

Propyl gallate 0.020 g

Potassium Chloride 1.140 g

Sodium metabisulphite 0.030 g

Poly(ethylene glycol)200 2.25 ml

Lactic acid 0.3 ml

Water (qsp)* 100 ml

*qsp= quantity sufficient to reach a total volume of 100ml

Example 3 of concentrated liquid formulate:

Citric acid 0.57 g

Sodium benzoate 0.03 g

Potassium chloride 1.14 g

Fumaric acid 0.10 g

Lactic acid 0.1 ml

Water (qsp)* 100 ml *qsp= quantity sufficient to reach a total volume of 100ml

For end use, the above-mentioned concentrated liquid formulates, as described in Examples 1 , 2, and 3 can be suitably diluted from 5 to 50% by volume/volume to give the liquid formulates according to the present description. The ideal dilution of the concentrated liquid formulates is of 35% by volume/volume.

The mixture, the formulates (concentrated or non-concentrated), or the carrier, both in solid and liquid form, according to the invention may be prepared as follows:

a) preparing the acids mixture and optional solubilising in a suitable solvent, preferably water; dissolving can be conveniently facilitated by heating (e.g., by keeping it at 30-50 °C for 10-60 minutes) or through the use of ultrasounds (e.g., 3 to 30 minutes), or by mechanical stirring;

b) weighing potassium chloride and optional solubilising in a suitable solvent, preferably water; dissolving can be conveniently facilitated by heating (e.g., by keeping it at 30-50 °C for 10-60 minutes) or through the use of ultrasounds (e.g., 3 to 30 minutes), or by mechanical stirring;

c) slowly adding the mixture or the solution obtained in b) to the mixture or the solution obtained in a).

The mixture, the formulates (concentrated or non-concentrated), or the carrier according to the invention could be used for the preparation of phytopharmaceutical compositions.

Said preparing will comprise a step of adding one or more phytopharmaceutically acceptable active ingredients to the carrier or to the mixture or to the formulates (concentrated or non-concentrated), as defined above, or as defined in the claims. The present description also relates to the use of any of the mixtures, of the formulates (concentrated or non-concentrated), or of the carrier as described herein or as defined in the claims for the endotherapeutical treatment of woody plants and of palms, wherein said mixture, or formulate, or carrier is administered to said plants by injection into their vascular system.

In particular, the present description also relates to a kit for the treatment of plants by injection into the vascular system, comprising one or more vials containing the mixture or the formulates (concentrated or non-concentrated) as described herein or as defined in the claims, and optionally one or more phytopharmaceutically acceptable solvents.

Moreover, said mixture, said formulates (concentrated or non-concentrated)or said solvent can further comprise one or more phytopharmacologically acceptable active ingredients.

The vials present in the kit may be, by way of a non-limiting example, cartridges or syringes apt to be used in devices for injection into the sap system of plants like, e.g., BITE-type devices as described, e.g., in Patent Applications PD2011A000245, EP2012/063680, WIPO WO/2013/010909, or in Montecchio 2013 "A Venturi Effect Can Help Cure Our Trees" J Vis Exp. 2013; (80): 51199.

The device as known in the literature and as described, e.g., in the abovecited documents, may be advantageously used for the administration of the mixture, of the carrier, or of the phytopharmaceutical composition according to the invention. The present description also relates to a method for the endotherapeutical treatment of woody plants or palms, comprising a step wherein a phytopharmaceutical composition comprising a mixture, a formulate (concentrated or non-concentrated), or the carrier as defined in any one of the claims or in the present description, and optionally one or more active phytopharmaceutical ingredients, is injected into the vascular system of said plants.

According to one preferred, but non-limiting embodiment, the injection is carried out by an endotherapy device such as, e.g., a Bite (blade for infusion in trees) device as defined above.

According to the present description, the treatment could be carried out with the sole mixture or with the sole formulate or with the sole carrier, which can act, e.g. by using at least citric acid or carboxylic acids, as chelating agent toward some constituent ions of xylem sap, known to a person skilled in the art (Haggag L.F., Fawzi M.I.F., Shahin M.F.M., El-Hady E.S., 2016. Effect of yeast, humic acid, fulvic acid, citric acid, potassium citrate and some chelated micro-elements on yield, fruit quality and leaf minerals content of "Canino" apricot trees. International Journal of ChemTech Research 9(4), 7-15). Other suitable acids may be one or more among malic, lactic, acetic, gluconic, fumaric, tartaric, adipic acid, and all mono-, di-, tri- and polycarboxylic acids at non-phytotoxic concentrations having the characteristics provided in the description or in any one of the claims.

By 'non-phytotoxic' it is meant a compound that, at the concentration of use, has no negative effects on plant health or on parts thereof. Since chelation stability constants are strongly affected by pH, an optimal range of pH of 2 to 5 of the solution of use of the mixture, or of the carrier as described herein, is envisaged. This pH value enables to involve the pectinic material of plant cell walls of xylem vessels, which is one of the main elements affecting hydraulic resistance.

Advantageously, it was also demonstrated that potassium ions increase the anti- oxidising properties in the plant and enhance plant resistance to biotic (phytopatogenetic microorganisms) and abiotic (drought, excessive exposure to light, etc.) stress (The Critical Role of Potassium in Plant Stress Response. Min Wang, Qingsong Zheng, Qirong Shen and Shiwei Guo. International Journal of Molecular Sciences. 2013, 14, 7370-7390).

Since potassium concentration in the apoplast is usually low, potassium ion tends to accumulate in vacuoles, and, along with chloride ion, increases their osmotic potential. This fact induces stomatal closure post-application, avoiding possible embolisms and fostering plant resistance and fostering plant resistance against hydric stress (Amelioration of water stress by potassium fertilizer in two oilseed species. H.R. Fanaei, M. Galavia, M. Kafi, A. Ghanbari Bonjar. International Journal of Plant Production 3 (2), 41-54).

Finally, the present description also relates to a phytotherapic composition comprising the mixture or the concentrated or non-concentrated liquid formulate or the carrier as defined in any one of the claims or in the present description, and optionally one or more phytopharmacologically acceptable active ingredients.

EXAMPLES

In all examples hereinafter, injections were carried out by natural infusion with Bite (blade for infusion in trees) instrument as described in Italian Patent Application PD2011A000245 and International Patent Application WO2013010909.

Example 1: injection of acid solutions on Tilia cordata

Five acids (citric, malic, adipic, acetic, hydrochloric) were dissolved or diluted in demineralized water at a concentration such as to obtain a solution with pH 2.5-2.6.

Molar concentrations used:

0.01 M citric acid (0.192 g/100 ml_)

0.016 M malic acid (0.215 g/100 ml_)

0.1 M adipic acid (1.461 g/100 ml_)

0.3 M acetic acid (1.716 ml_/100 mL)

0.0025 M hydrochloric acid (0.008 mL/100 mL)

The injection rate was tested on Tilia cordata, with 3 replicates per solution; demineralized water was used as control.

Results are reported in Figure 1.

Example 2: injections of citric acid solutions on Tilia cordata Citric acid was dissolved in demineralized water until obtaining 7 dilutions in a range of 0.0003 M (0.006 g/100 ml_) to 0.1 M (1.92 g/100 ml_). The pH of each solution was measured. Their injection rate was tested on Tilia cordata, with 3 replicates per solution; demineralized water was used as control.

Results are reported in Figure 2.

Example 3: variation of citric acid solutions with potassium chloride addition

Citric acid was dissolved in demineralized water at 0.01 M (0.192 g/100 ml_) and 0.02 M (0.384 g/100 ml_) concentrations; potassium chloride was added at a 0.05 M (0.373 g/100 ml_) concentration. Their injection rate was tested on Tilia cordata; demineralized water was used as control.

Results are reported in Figure 3.

Example 4: injection speed of acid solutions with potassium chloride addition on Fraxinus excelsior

Three acids (citric, maleic, acetic) were dissolved or diluted in demineralized water at the following molar concentrations:

Citric acid 0.01 M (0.192 g/100 ml_)

Maleic acid 0.016 M (0.371 g/100 ml_)

Acetic acid 0.3 M (1.716 ml_/100 ml_)

Injection speed for each solution was tested on Fraxinus excelsior in triplicate; demineralized water was used as reference solution.

Results are reported in figure 4.

Example 5: injection rate of 0.01 M citric acid solution on Ceitis austraiis and Betula pendula

Citric acid was dissolved in demineralized water at 0.01 M (0.192 g/100 ml_) concentrations. Its injection rate was tested on Ceitis austraiis and Betula pendula; demineralized water was used as control.

Example 6: injection rate of 0.01 M citric acid solution on 7 tree species

Citric acid was dissolved in demineralized water at the 0.01 M (0.192 g/100 ml_) concentration. The commercial product Vertimec EC (Syngenta Italia S.p.A) was diluted to 4% in water or with 0.01 M (0.192 g/100 mL) citric acid or in solvent Biotek-JET (Lamas s.r.l., San Marino). Its injection rate was tested on Juglans nigra, Cedrus deodara, Fraxinus excelsior, Acer sp., Pinus pinea, Cedrus libani, Cedrus atlantica; demineralized water was used as control.

Example 7: absence of phytotoxicity

A citric acid phytotoxicity assay was carried out, assayed at 0.005 M (0.096 g/100 mL) and 0.01 M (0.192 g/100 mL) concentrations in demineralized water, with leaves of Salix alba, Prunus avium and Malus sp. Any presence of phytotoxicity symptoms was assayed after 24 and 48 hours, by observing any presence of chlorosis or necrosis on foliar surface (Vikrant et al., 2006; Martos et al., 2008; EPPO, 2014). No phytotoxicity symptom was detected at 24 and at 48 hours for both solutions on all species assayed.

EPPO, 2014. PP 1/135 (4) Phytotoxicity assessment. EPPO Bull. 44, 265-273.

Martos S., Andolfi A., Luque J., Mugnai L, Surico G., Evidente A., 2008. Production of phytotoxic metabolites by five species of Botryosphaeriaceae causing decline on grapevines, with special interest in the species Neofusicoccum luteum and N. parvum. European Journal of Plant Pathology 121 : 451-461.

Vikrant P., Verma K. K., Rajak R. C, Pandey A. K., 2006. Characterization of a phytotoxin from Phoma herbarum for management of Parthenium hysterophus L. Journal of Phytopathology 154: 461-468.

Claims

1. A mixture consisting of one or more inorganic acids or one or more carboxylic acids, or a combination thereof at a total weight/weight concentration of

20 to 60%, and one or more potassium chloride at a weight/weight concentration of 80 to 40% of said mixture and, optionally, one or more phytopharmacologically acceptable active ingredients.

2. The mixture according to claim 1 , wherein said one or more carboxylic acids are monocarboxylic, dicarboxylic, tricarboxylic and/or polycarboxylic acids.

3. The mixture according to claim 2, wherein said acids are aliphatic saturated or unsaturated organic acids with linear or branched or cyclic C1-C16 carbon chains, and/or aromatic acids.

4. The mixture according to claim 2 or 3, wherein said acids are acetic acid, propionic acid, butyric acid, capric acid, caprylic acid, glutaric acid, succinic acid, tartaric acid, fumaric acid, maleic acid, adipic acid, citric acid, salicylic acid, caffeic acid, benzoic acid, cynnamic acid; optionally substituted with amino, keto and/or hydroxy groups; and/or inorganic acids such as boric acid, hydrochloric acid.

5. The mixture according to claim 4, wherein said substituted acids are aspartic acid, malic acid, glutamic acid, p-cumaric acid.

6. A concentrated liquid formulate comprising from 0.2 to 10 % by weight/volume of the mixture according to any one of claims 1 to 5 and at least one phytopharmacologically acceptable solvent.

7. The concentrated liquid formulate according to claim 6, wherein said solvent is water, or an aqueous solution of water-miscible solvents, an aqueous solution of water-soluble active ingredients, an aqueous solution of formulations of water- miscible active ingredients.

8. A liquid formulate comprising from 5 to 50% by volume/volume of the concentrated formulate according to any one of claims 6 or 7 and a phytopharmacologically acceptable solvent.

9. The liquid formulate according to claim 8, wherein said solvent is water, or an aqueous solution of water-miscible solvents, an aqueous solution of water-soluble active ingredients, an aqueous solution of formulations of water-miscible active ingredients.

10. The formulate according to any one of claims 6 to 9, characterised in that it has a pH not greater than 6 and not less than 2.

1 1. A phytopharmaceutical carrier comprising the mixture according to any one of claims 1 to 5 and at least one phytopharmacologically acceptable excipient and/or solvent.

12. The phytopharmaceutical carrier according to claim 1 1 , wherein said acids have a final concentration of 0.12 to 0.34% by weight/volume and said sodium chloride has a final concentration respectively from 0.46 to 0.23% by weight/volume, wherein said carrier is injectable into the vascular system of woody plants or palms.

13. A phytopharmaceutical composition comprising the mixture according to any one of claims 1 to 5 or the formulate according to any one of claims 6 to 9 or the phytopharmaceutical carrier according to claim 11 and one or more phytopharmacologically acceptable active ingredients.

14. The phytopharmaceutical carrier according to any one of claims 11 or 12, or the composition according to claim 13, characterised in that it has a pH not greater than 6 and not less than 2.

15. Use of any of the mixtures as defined in claims 1 to 5, or the formulate according to any one of claims 6 to 10, or of the carrier according to any one of claims 1 1 , 12 or 14, for the preparation of phytopharmaceutical compositions.

16. The use of any of the mixtures as defined in claims 1 to 5, or the formulate according to any one of claims 6 to 10, or of the carrier according to any one of claims 1 1 , 12 or 14, or of the composition according to claims 13 or 14 for the endotherapeutical treatment of woody plants or palms, wherein said mixture or carrier is administered by injection into the vascular system of said plants or of said palms.

17. A kit for the treatment of plants by injection into the vascular system comprising one or more vials containing the mixture according to any one of claims 1 to 5 or the formulate according to any one of claims 6 to 10 and optionally one or more phytopharmaceutically acceptable solvents, each dosed in the same or separated vials.

18. The kit according to claim 16, wherein said mixture or said solvent further comprises one or more phytopharmacologically acceptable active ingredients.

19. A method for the endotherapeutical treatment of woody plants or palms, comprising at least a step wherein a phytopharmaceutical composition comprising a formulate as defined in any of the claims 6 to 10, or a carrier as defined in claims 1 1 , 12 or 14, or a phytopharmaceutical composition as defined in claims 13 or 14, is injected into the vascular system of said woody plants or palms.

20. The method according to claim 19, wherein said injection is carried out by Bite (blade for infusion in trees) technology.