RO133307A2 - Liquid foliar fertilizer with bio-stimulant and process for its preparation - Google Patents

Abstract

The invention relates to a composition of foliar liquid fertilizer and to a process for its preparation. According to the invention, the composition comprises, as macroelements: 70...112 g/l total nitrogen, 31...80 g/l soluble phosphorus, 36...80 g/l water-soluble potassium, 5...20 g/l glycyl betaine from natural sources, as microelements: 0.35...0.45 g/l iron, 0.33...0.40 g/l manganese, 0.15...0.22 g/l copper, 0.10...0.15 g/l magnesium, 0.04...0.08 g/l zinc, 0.018...0.023 g/l molybdenum, 0.04...0.07 g/l selenium, conditioning adjuvants: 10...150 g/l glycerine and/or polyols and water-soluble and fat-soluble surface-active substances, as well as 0.35...0.7 g/l salicylic acid and deionized water. The claimed process consists in preparing a microbiogically-stable solution by diluting, with deionised water, a standardized vinasse resulting from bakery yeast production or molasses resulting from sugar production, having a content of 5...20% glycyl-betaine and adding salicylic acid, preparing the macroelements solution and the microelements solution, whereto conditioning adjuvants are added, after which it is added over the macroelements solution, while continuously stirring, to result in a solution of liquid fertilizer which is recirculated through a homogenization system under pressure for stabilization.

Description

The invention relates to a composition of foliar liquid fertilizer containing macroelements, microelements and betainic biostimulant and to a process for making it.

They are known from the patent literature (RO 198954, RO 108953, RO 91355, RO 93426), a series of processes for obtaining liquid fertilizer compositions for foliar application, containing the macro-elements nitrogen, phosphorus, potassium, as well as a number of essential microelements, as iron, manganese, copper, boron, cobalt, zinc etc. The processes generally consist in the neutralization in the aqueous phase of phosphoric or nitric acid with ammonia, carbonate or potassium hydroxide, with the addition of urea to ensure the need for amide nitrogen, and to the solution thus prepared are added the microelements in the form of sulphates or nitrates, the products ensuring by foliar application an additional fertilization of the crop plants as well as the correction of nutritional deficiencies of the plants.

From the patents RO 103652, RO 95689, RO 116080, RO 116081, RO 116189, US ni

5302180, US 7198805, is known a wide range of foliar application fertilizers, containing nitrogen, phosphorus, potassium and microelements, which additionally contain a series of natural or synthetic organic substances, plant extracts, protein hydrolysates or glycoproteins, naphthenates, polycarboxylic acids, humic substances, introduced in order to stimulate the metabolism of the nutrients and to facilitate the absorption and penetration by leaves of the nutritional species.

Also, patents RO 127192 and RO 127894 describe compositions of liquid complex fertilizer with humic substances, containing total nitrogen, phosphorus, potassium, microelements iron, zinc, copper, manganese, magnesium complexed with disodium salt of EDTA and organic substances, the resulting fertilizer having a pH = 6.8 ... 8.4. The process for obtaining it consisted in neutralizing the solution with humic and fulvic acids with potassium carbonate, after which to the mixture thus obtained was added a solution of complexes and microelements complexed with disodium salt of EDTA, and finally urea was added.

A disadvantage of such liquid compositions that contain significant amounts of biodegradable organic matter is determined by the fact that they do not contain betainic biostimulants that ensure a significant resistance of plants to abiotic and saline abiotic stress. Also, the lack of specific conditioning adjuvants may result in their poor adherence to the foliage of the crop plants, in the case of an extra-root application, these compositions also having a stability

reduced by the tendency to precipitate humic acids in aqueous solutions. According to a generally accepted definition at the level European Union

(http://www.biostimulants.eu/), plant biostimulant is any substance from natural sourcesep-sb ^x I / \

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10/30/2017 or microorganisms whose function, when applied on plants or in the rhizosphere, is to stimulate natural processes to increase / promote nutrient absorption, nutrient efficiency, tolerance to abiotic stress and crop quality. By extension, plant biostimulants also designate commercial products that contain mixtures of such substances and / or microorganisms. It is well known in the literature the biostimulatory effect of derivatives with betaine structure - including glycyl betaine - on the development of plants, which favorably influence stress resistance - especially the abiotic stress generated by the lack of water or an excess of salts - of plants (Patrick du Jardin, Plant biostimulants: Definition, concept, main categories and regulation, Scientia Horticulturae 196 (2015) 3-14).

The technical problem to be solved by the invention consists in obtaining fertilizing compositions with physico-chemical stable foliar application based on macro- and microelements containing also biostimulants from natural sources, with high efficiency on the development of crop plants on various vegetation phases, ensuring a their increased resistance to stressors, especially the abiotic or saline stress, which significantly affects crop productivity and quality.

The composition of foliar liquid fertilizer containing macroelements, microelements and betainic biostimulant according to the invention contains: macroelements 70 ... 112 g / liter total nitrogen, 31 ... 80 g / liter soluble phosphorus (expressed as P2O5), 36 ... 80 g / liter of water-soluble potassium (expressed as K2O),

5 ... 20 g / liter glycyl betaine from natural sources, microelements: 0.35 ... 0.45 g / liter iron, 0.33 ... 0.40 g / liter manganese, 0.15 ... 0 , 22 g / liter copper, 0.10 ... 0.18 g / liter boron, 0.10 ... 0.15 g / liter magnesium, 0.04 ... 0.08 g / liter zinc, 0.018 ... 0.023 g / liter molybdenum, 0.04 ... 0.07 g / liter selenium, as well as 10 ... 150 g / liter glycerin and / or natural or synthetic polyols, 0.35 ... 0.7 g / liter salicylic acid and 10 ... 150 g / liter water-soluble and fat-soluble surfactants, the rest deionized water.

The process of obtaining the foliar liquid fertilizer containing macroelements, microelements and betainic biostimulant according to the invention consisted of the following steps:

- the realization under intense agitation of a microbiologically stable solution from the natural source of glycyl betaine, by diluting with deionized water the standardized vinegar resulting in the production of baking yeast or molasses resulting in the production of sugar, having a continuous of 5 ... 20% glycyl betaine and a protein content of up to 5%, and the addition of 5 to 10 grams of salicylic acid or sodium salicylate;

- realization of the microelement solution, by adding to the stabilized solution of glycyl betaine the salts of microelements Fe, Mn, Cu, B, Mg, Zn, Mo, Se, together with EDTA disodic or tetrasodic salt in sufficient quantity for the complete chelatization of the microelements from the salts introduced;

- realization of the macroelement solution, by neutralizing an aqueous solution of phosphoric acid with potassium hydroxide, followed by the addition of urea and / or ammonium nitrate, iii of 2017 00885

10/30/2017 quantities to ensure a continuous 70 ... 112 g / liter total nitrogen, 31 ... 80 g / liter soluble phosphorus (expressed as P2O5), 36 ... 80 g / liter soluble potassium in water (expressed as K2O); adding in the macro-solution of the conditioning aids, consisting of

10 ... 150 g / liter glycerin and / or natural or synthetic polyols and 10 ... 150 g / liter water-soluble and fat-soluble surfactants;

adding the microelement solution with biostimulants over the macroelement solution, under continuous stirring, with the formation of the foliar liquid fertilizer composition;

homogenizing and stabilizing the solution of foliar liquid fertilizer by subjecting it to a pressure of at least 150 bar for 30 ... 90 minutes, by recirculating it through a system of homogenization under pressure, capable of achieving a pressure of at least 150 bar.

The foliar liquid fertilizer according to the invention is perfectly miscible with water in any proportion, as well as with a wide range of agrochemicals used in the treatment of plants, having a balanced ratio of macronutrients and quantities of micronutrients and biostimulants that favor a very efficient and fast supplementary nutrition. plants, for various phases of vegetation.

By applying the invention, the nutrition of the plants is optimized, the root and extraradical vegetative development is significantly stimulated, the resistance of the plants to the factors of climatic stress is increased, especially the resistance to the water stress, at the same time with a substantial increase in the productivity and quality of the agricultural products.

3 examples of embodiments of the invention are given below, which are not limiting.

Example 1. As the source of natural betainic biostimulant, a standardized aqueous solution of vinegar, derived from the manufacture of baking yeast, containing 12 ... 15% glycylbetaine, 5 ... 21% crude protein, 5. was used. .7% potassium and 5 ... 15% amino acids and peptides from protein hydrolysates from yeast manufacture.

In a stirring vessel with the capacity of about 1 liter, add 100 g of standardized vinegar with the above composition, over which add 250 ml deionized water. Start stirring energetically for 20 minutes and, under continuous stirring, introduce the following amounts of metal salts - the source of microelements:

Source of microelements

Iron sulphate FeSO4.7H2O

Manganese sulphate MnSO4 H2O

Copper sulphate CUSO4.5H2O

Boric acid H3BO3

Magnesium sulphate MgSO4.7H2O

Zinc sulphate ZnSC> 4.7H2O

Sodium molybdate Na2MoC> 4.2H2O

Sodium selenate Na2SeO4

Quantity (g)

1.1

0.9

0.7

1.1

0.25

0.05

0.15

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10/30/2017

Add 4 g of citric acid to facilitate complete solubilization. After their complete solubilization, 8 kg of Na4-EDTA chelating agent (tetrasodic salt of ethylenediaminetetraacetic acid) is added to chelate the metal elements. Under continuous stirring, adjust the pH of the microelement solution in the range 5.5-6.5, by adding 0.5 g of salicylic acid. There is a process of chelating the metallic elements, with their rapid solubilization and changing the color of the solution from greenish-white to dark-green, clear blue.

In another stirring vessel with a capacity of about 2 liters, 400 ml deionized water is introduced, over which 57 g of 85% phosphoric acid are added and homogenized for 15-30 minutes. Under continuous stirring, 40 kg of technical solid potassium hydroxide (minimum 90%) is added gradually over the phosphoric acid solution. After dosing the whole amount of KOH, the pH of the solution is measured, which should be in the range 5.2-7.0. Otherwise, it is adjusted by additional dosage of phosphoric acid (if larger), or KOH (if smaller). Under continuous stirring, the reaction mass is cooled down until the temperature drops below 50 ° C, and at this temperature, 228 kg of urea granules are added (46% N, gradually, under continuous stirring. The reaction mass is gradually cooled, due to the process Endotherm for dissolving urea in water After the entire amount of urea has been added, stirring is continued until the entire amount of urea is dissolved, add 5 kg of potassium chloride KC1 and 5 kg of potassium sulfate K2SO4, and stir for solubilization. , making an aqueous solution of macroelements with a mass ratio N: P ₂ O ₅ : K ₂ O of 3: 1: 1.

Separately, a mixture of 75 g of 99% glycerin, 25 g of surfactant SPAN 80 (sorbitan monooleate) and 50 g surfactant Lutensol TO 10 (fatty alcohols C ₁₂ ... C ₅ ethoxylates with 10 moles of ethylene oxide) is added. 3 g polydimethylsiloxane antifoam, under vigorous stirring. After complete homogenization, the mixture of additives is added over the macronutrient solution, maintaining the temperature of 3O ... 5O ° C for optimum homogenization of the mixture.

Next, add the solution of microelements and biostimulants over the solution of macroelements, cool below 25 ° C, add deionized water up to 1 liter and recycle for 2 hours through a pressure homogenizer with pistons which ensures a pressure of 200 bar work, at a weak 11 liters / hour.

After 2 hours of recirculation through the homogenizer, a homogeneous composition of foliar liquid fertilizer, of dark brown color, having a density of 1.195 kg / liter, a pH of 7.05 and containing 105 g / liter of total nitrogen, 37 g is obtained. / liter P ₂ 0s, 39.7 g / liter K ₂ O and 14.5 g / liter glycyl betaine, showing good physical and chemical stability for a storage period of more than 6 months without tendency to deposit or separation .

Example 2. Has the procedure been similar to Example 1, with the exception that it was used as the source of 7 betainic natural biostimulant, an aqueous fraction of standardized molasses, derived from the manufacture of ' ^Λ -' *? sugar, which contains 5 ... 9% glycyl betaine, 44 ... 52% total sugar, 7.5 ... 12% mineral substances,

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1,2 ... 2,4% total nitrogen, alloys of vitamins and amino acids in very small quantities, and as a source of nitrogen a mixture of urea and ammonium nitrate granules was used.

Thus, in a stirring vessel with a capacity of about 1 liter, 200 g molasses containing 7% glycyl betaine and 47% total sugar are added, on top of which 300 ml deionized water is added. Start stirring energetically for 20 minutes and, under continuous stirring, introduce the following amounts of metal salts - the source of microelements:

Source of microelements Quantity (g) Iron sulphate FeSO4.7H2O 3 Manganese sulphate MnSO ₄ H2O 1.1 Copper sulphate CUSO4.5H2O 0.9 Boric acid H3BO3 0.7 Magnesium sulphate MgSO4.7H2O 1.1 ZnSO4.7H zinc sulphate ₂ O 0.25 Sodium molybdate Na2MoO ₄ .2H2O 0.05 Sodium selenate Na2SeO4 0.15

Add 4 g of citric acid to facilitate complete solubilization. After their complete solubilization, 8 kg of Na4-EDTA chelating agent (tetrasodic salt of ethylenediaminetetraacetic acid) is added to chelate the metal elements. Under continuous stirring, adjust the pH of the microelement solution in the range 5.5-6.5, by adding 0.5 g of salicylic acid. There is a process of chelating the metallic elements, with their rapid solubilization and changing the color of the solution from greenish-white to dark-green, clear blue.

In another stirring vessel with a capacity of about 2 liters, 350 ml deionized water is introduced, over which 57 g of 85% phosphoric acid are added and homogenized for 15-30 minutes. Under continuous stirring, 40 kg of technical solid potassium hydroxide (minimum 90%) is added gradually over the phosphoric acid solution. After dosing the whole amount of KOH, the pH of the solution is measured, which should be in the range 5.2-7.0. Otherwise, it is adjusted by additional dosage of phosphoric acid (if larger), or KOH (if smaller). Under continuous stirring, the reaction mass is cooled down until the temperature drops below 50 ° C, and at this temperature, a mixture of 114 g urea granules (46% N) and 187 g ammonium nitrate granules (28% N) is added. , gradually, under continuous stirring. The reaction mass is gradually cooled, due to the endothermic process of dissolving urea and ammonium nitrate in water. After the whole amount of urea and nitrogen has been added, stirring is continued until the whole amount of urea and nitrogen is dissolved. Add 5 kg of potassium chloride KC1 and 5 kg of potassium sulphate K2SO4, and stir for solubilization, obtaining an aqueous solution of macroelements with a mass ratio N 3 Os ^ O of 3: 1: 1.

Separately prepare a mixture of 50 g of 99% glycerin, 25 g of surfactant SPAN 80 (sorbitan monooleate) and 50 g surfactant LAURETH 9 (C12 ... C15 fatty alcohols with 9 moles of ethylene oxide), to which is added 3 g of antifoam polydimethylsiloxane, under vigorous stirring. Because the amount of. introduced molasses contains about 80 g polyols as sugary substances, it is no longer necessary

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10/30/2017 introduction into the composition of aglycerin or other depolole forms. After complete homogenization, the mixture of surfactants is added over the macronutrient solution, maintaining the temperature of 30 ... 50 ° C for optimum homogenization of the mixture.

Next, add the solution of microelements and biostimulants over the solution of macroelements, cool below 25 ° C, add deionized water up to 1 liter and recycle for 2 hours through a pressure homogenizer with pistons which ensures a pressure of 200 bar work, at a weak 14 liters / hour.

After 2.5 hours of recirculation through the homogenizer, a homogeneous composition of foliar liquid fertilizer, yellow-brown, having a density of 1.21 kg / liter, a pH of 6.87 and containing 107.3 g / is obtained. total nitrogen liter, 34.8 g / liter P2O5, 36.3 g / liter K2O and 12.8 g / liter glycyl betaine, which has good physical and chemical stability for a storage period of more than 6 months without trends deposit or separation.

Example 3. It was performed similar to Example 1, using the other ratio of the raw materials used as the source of macronutrients, so that finally a composition of foliar liquid fertilizer with a mass ratio between macronutrients N: P2Os: K2O of 1 was obtained. 1: 1.

As the source of the natural betainic biostimulant, the standardized aqueous vinegar solution described in Example 1 was used.

Thus, in a stirring vessel with the capacity of about 1 liter, 100 g of standardized vinegar with the above composition is introduced, over which 250 ml deionized water is added. Start stirring energetically for 20 minutes and, under continuous stirring, introduce the following amounts of metal salts - the source of microelements:

Source of microelements

Iron sulphate FeSO4.7H2O

Manganese sulphate MnSChIUO

Copper sulphate CUSO4.5H2O Boric acid H3BO3

Magnesium sulphate MgSO4.7H2O

ZnSO4.7H2O zinc sulphate

Sodium molybdate Na2MoO4.2H2O Sodium selenate Na2SeO4

Quantity (g)

1.1

0.9

0.7

1.1

0.25

0.05

0.15

Add 4 g of citric acid to facilitate complete solubilization. After their complete solubilization, 8 kg of Na4-EDTA chelating agent (tetrasodic salt of ethylenediaminetetraacetic acid) is added to chelate the metal elements. Under continuous stirring, adjust the pH of the microelement solution in the range 5.5-6.5, by adding 0.5 g of salicylic acid. There is a process of chelating the metallic elements, with their rapid solubilization and changing the color of the solution from greenish-white to dark-green, clear blue.

In another stirring vessel with the capacity of about 2 liters, 400 ml deionized water is introduced, ⁴ . upon which 123 g of 85% phosphoric acid was added and stirred for 15-30 minutes. Under shaking Vv - / a 2017 00885

30/10/2017 continues, gradually adding under stirring and cooling over the phosphoric acid solution, 62 kg technical solid potassium hydroxide (minimum 90%). After dosing the whole amount of KOH, the pH of the solution, which should be in the range 5.0-6.5, is measured. Otherwise, it is adjusted by additional dosage of phosphoric acid (if larger), or KOH (if smaller). Under continuous stirring, the reaction mass is cooled down until the temperature drops below 50 ° C, and at this temperature, 163 kg urea granules (46% N) are added, gradually, under continuous stirring. The reaction mass is gradually cooled, due to the endothermic process of dissolving urea in water. After the entire amount of urea has been added, stirring is continued until the entire amount of urea is dissolved. 19 kg of potassium chloride KC1 and 22 kg of potassium sulphate K2SO4 were added and stirred for solubilization, making an aqueous solution of macroelements with a mass ratio N ^ Os ^ O of 1: 1: 1.

Separately, a mixture of 75 g of 99% glycerin, 25 g of surfactant SPAN 80 (sorbitan monooleate) and 50 g surfactant Lutensol TO 10 (C12 ... C15 fatty alcohols with 10 moles of ethylene oxide) is added, to which is added 3 g. polydimethylsiloxane antifoam, under vigorous stirring. After complete homogenization, the mixture of additives is added over the macronutrient solution, maintaining the temperature of 30 ... 50 ° C for optimum homogenization of the mixture.

Next, add the solution of microelements and biostimulants over the solution of macroelements, cool below 25 ° C, add deionized water up to 1 liter and recycle for 2 hours through a pressure homogenizer with pistons which ensures a pressure of 200 bar work, at a weak 11 liters / hour.

After 3 hours of recirculation through the homogenizer, a homogeneous composition of foliar liquid fertilizer, of dark brown color, having a density of 1.22 kg / liter, a pH of 6.28 and containing 75.5 g / liter of nitrogen is obtained. total, 75.1 g / liter P2O5, 76.2 g / liter K2O and 14.0 g / liter glycyl betaine, which has good physical and chemical stability for a storage period of more than 6 months without tendency to deposit or separation.

The foliar liquid fertilizers containing betainic biostimulants from natural sources, prepared according to Examples 1 ... 3 were tested under field conditions on a number of crops, on different soils, the results of these tests, particularly efficient, are presented in the Tables below .

Table 1. The productive efficiency of fertilization with liquid foliar fertilizers cf. 1-3, applied to tomatoes, Buzau variety, cultivated on cernoziom cambie in the field, with irrigation.

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1 Unfertilized witness - - - - 38.147 - 100.0 - 2 Ingram. foliar cf. 1 (FI) 3 1.0 3 9 52.567 14.420 137.8 1602 3 Ingram. foliar cf. 2 (F2) 3 1.0 3 9 53.235 15.106 139.6 1678 4 Ingram. foliar cf. 3 (F3) 3 1.0 3 9 51.122 12.975 134.0 1441

*) Without basic soil fertilization

Table 2. Productive efficiency of fertilization with liquid foliar fertilizers cf. 1-3, applied to the potato, the Sânte variety, cultivated on the cernoziom cambie in the field, without irrigation.

No. Crt. Fertilization treatment * Nr. treat the minds I have a solution to the application Amount of fat used, L / ha Fruit product, kg / ha Production increase at a treat total kg / ha % Kg / liter leaf fat 1 Unfertilized witness - - - - 20789 - 100.0 - 2 Ingram. foliar cf. 1 (FI) 3 1.0 3 9 28651 7862 137.8 873,5 3 Ingram. foliar cf. 2 (F2) 3 1.0 3 9 29027 8238 139.6 915.3 4 Ingram. foliar cf. 3 (F3) 3 1.0 3 9 27211 6422 713.5

*) Without basic soil fertilization

Table 3. The productive efficiency of fertilization with liquid foliar fertilizers cf. 1-3, applied to wheat, Glosa variety, cultivated on vermicelli cernoziom in the field

No. Crt. Fertilization treatment * Nr. treat the minds I have a solution to the application Amount of fat used, L / ha Fruit product, kg / ha Production increase at a treat total kg / ha % Kg / liter leaf fat 1 Wet fertilized soil - - - - 5250 - 100.0 - 2 Ingram. foliar cf. 1 (FI) 3 1.0 3 9 7161 1911 136.4 212.3 3 Ingram. foliar cf. 2 (F2) 3 1.0 3 9 6972 1722 132.8 191.3 4 Ingram. foliar cf. 3 (F3) 3 1.0 3 9 7749 2499 147.6 277

*) Basic soil fertilization with N-90, P2O5-115 kg / ha

Claims (3)

claims 1. Composition of foliar liquid fertilizer containing macroelements, microelements and betainic biostimulant, characterized in that it contains: macroelements 70 ... 112 g / liter total nitrogen, 31 ... 80 g / liter soluble phosphorus expressed as P2O5, 36. ..80 g / liter water soluble potassium expressed as K2O, 5 ... 20 g / liter glycyl betaine from natural sources, microelements: 0.35 ... 0.45 g / liter iron, 0.33 ... 0 , 40 g / liter manganese, 0.15 ... 0.22 g / liter copper, 0.10 ... 0.18 g / liter boron, 0.10 ... 0.15 g / liter magnesium, 0 , 04 ... 0.08 g / liter zinc, 0.018 ... 0.023 g / liter molybdenum, 0.04 ... 0.07 g / liter selenium, as well as 10 ... 150 g / liter glycerine and / or natural or synthetic polyols, 0.35 ... 0.7 g / liter salicylic acid and 10 ... 150 g / liter water-soluble and fat-soluble surfactants, the rest up to 1 liter deionized water. 2. A process for obtaining the composition of foliar liquid fertilizer containing the macroelements, microelements and betainic biostimulant described in claim 1, characterized in that it contains the following steps: the realization under intense agitation of a microbiologically stable solution of the natural source of glycobetaine, by diluting with deionized water the standardized vinegar resulting in the production of baking yeast or molasses resulting in the production of sugar, having a continuous of 5 .. .20% glycyl betaine and a maximum of 5% protein content, and adding a quantity of 5 .. .10 grams of salicylic acid or sodium salicylate; making the microelement solution, by adding to the stabilized glycyl betaine solution of the microelement salts Fe, Mn, Cu, B, Mg, Zn, Mo, Se, together with EDTA disodic or tetrasodic salt in sufficient quantity for the complete chelation of the microelements from the salts introduced and the microbiological stabilization with salicylic acid or its salts; - realization of the solution of macroelements, by neutralizing an aqueous solution of phosphoric acid with potassium hydroxide, followed by the addition of urea and / or ammonium nitrate, in quantities that will provide a content of 70 ... 112 g / liter total nitrogen, 31 ... 80 g / liter soluble phosphorus (expressed as P2O5), 36 ... 80 g / liter water soluble potassium (expressed as K2O); adding in the macro-solution solution of the conditioning aids, consisting of 10 ... 150 g / liter glycerin and / or natural or synthetic polyols and 10 ... 150 g / liter water-soluble and fat-soluble surfactants; adding the microelement solution with biostimulants over the macroelement solution, under continuous stirring, with the formation of the foliar liquid fertilizer composition; homogenization and stabilization of the solution of foliar liquid fertilizer by subjecting it to a pressure of at least 150 bar for 30 ... 90 minutes, by recirculating it through a system of homogenization under pressure, capable of achieving a pressure of at least 150 bar.