Method for improving the cultivation of plants under abiotic stress conditions

Abstract

The present invention falls within the technical field of agricultural farming under abiotic stress conditions and discloses a method intended to improve the yield and efficacy of the cultivation of plants that combines applying a biostimulant product to the aerial parts of the plant and selecting a specific biostimulant product based on a filtrate that is free from cells of fungal origin and obtained from the cultivation of fungi of the genus Trichoderma. Said method aims to revert or prevent the alteration of the expression of genes related to the primary metabolism of carbohydrates, lipids and amino acids, and secondary metabolism, the production and signalling of hormones, the synthesis and processing of RNA, the synthesis, modification and stabilisation of proteins, the transport of solutes and nutrients, and the structure of the cell wall in plants.

Description

[0001] DESCRIPTION METHOD FOR IMPROVING PLANT CULTIVATION UNDER ABIOTIC STRESS CONDITIONS Field of the invention The present invention falls within the agricultural sector. Specifically, it relates to methods intended to improve plant cultivation under abiotic stress conditions through the application of biostimulant compositions to the aerial parts of the plants. Background Drought and salinization caused by global warming are by far the main environmental stress factors in agriculture that limit the overall productivity of major crops by directly reducing the potential yield of plants, but also by indirectly influencing their interactions with biotic factors that play a fundamental role in global food security. The expected climate changes will have adverse effects on the yield and functionality of crops, mainly in cereals (rice, wheat and corn),tomate, sunflower and cotton 1,2In the Mediterranean countries of southern Europe, drought and salinization are expected to severely reduce the yield and quality of important vegetable crops such as tomatoes. This reduction will be particularly severe in Spain, one of the world's largest tomato producers. In addition to the problems arising from human-caused global warming, the environmental damage inflicted by practices based on the depletion of soil and water resources and the intensive application of nitrogen and phosphate fertilizers has become a major limitation to conventional agriculture.Therefore, it is mandatory to establish strategies for sustainable and environmentally friendly agriculture aimed at improving crop yield, drought and salinity tolerance, and water and nutrient use efficiency, while reducing the negative impact of agrochemicals on the environment. Over the past ten years, accumulating evidence has shown that many of these goals can be achieved through the use of biostimulants, defined as any substance or microorganism applied to plants that stimulates natural processes to improve nutrient efficiency, abiotic stress tolerance, and / or crop quality traits, regardless of their nutrient content. .Plants are not axenic organisms, but metaorganisms that host a complex and dynamic microbial consortium of bacteria, fungi, archaea, and protists that communicate with plants by exchanging chemical signals throughout the phytosphere. These symbiotic interactions are important not only for plant productivity, quality, and fitness, but also for the functioning of terrestrial ecosystems. 4,5,6. Therefore, understanding the relationships between plant growth and soil microbial populations is necessary when seeking new and efficient agricultural and ecological intensification strategies to improve yield and tolerance to abiotic and biotic stresses. A common, safe, and environmentally friendly practice to increase crop yield and / or protect plants from abiotic stress and pests, while reducing the use of agrochemicals, is based on soil inoculation with plant growth-promoting microorganisms that act as biostimulants7,8,9,10,11. US patent US8716001B2 describes a method for enhancing plant growth that comprises contacting a Trichoderma strain with the plant under conditions effective for the Trichoderma strain to colonize the plant roots, thereby creating a plant-Trichoderma system.The patent describes methods for improving plant resistance to abiotic stress, increasing nitrogen use efficiency in plants, reducing nitrous oxide emissions into the air, reducing nitrate leaching into soil and water, and enhancing carbon sequestration from the air. US patent application US2020275618 also describes a plant system that promotes plant resistance to stress growing conditions ^^ ...US patent US11118159 relates to the desert endophytic bacterium SA187, which can provide resistance or tolerance to abiotic stress conditions in seeds or plants. Compositions containing SA187 can be used to improve plant development and performance under environmental stress conditions. Although microbial products have enormous potential to contribute to economic growth and sustainable agricultural development, many challenges limit the widespread adoption of this technology worldwide. Limitations in their application are often related to the differential efficacy of microbial products under controlled laboratory conditions. o greenhouse, to field conditions 12 . It is even possible that the effectiveness of a microbial product may vary depending on the type of soil, crop or environment used, which quelimits its wider adoption by farmers 13 The effectiveness of the product may also be compromised because the native microbial communities associated with a plant or soil may outnumber the inoculated microbes, causing the latter to disappear within a matter of weeks or persist at low and ineffective levels. 14 .Other factors, such as extreme climatic conditions, soil characteristics, and the presence of environmental or soil contaminants, can also reduce the efficacy of a strain compared to the same strain under controlled conditions. Additionally, other practical problems with the use of microbial inoculants include incompatibility with agrochemicals or with the farmer's equipment and production practices. Finally, storage and transportation problems for these types of products are also notable, as are the corresponding practical difficulties in implementing their use in developing regions, due to both a lack of scientific knowledge and awareness.Beneficial microorganisms applied directly to the soil emit diffusible substances including phytohormones, carbohydrates, proteins, fatty acids, flavonols, organic acids, amino acids and volatile compounds that promote root branching and nutrient uptake, enhance photosynthesis, alter metabolism, confer resistance to abiotic stresses and. patógenos 16,17 , and stimulate beneficial microbial communities residing in the soil and phytosphere,18,19,20,21,22 thereby boosting plant growth and yield. Agronomic studies have consistently shown that soil application of cell-free culture (CF) filtrates of plant-associated beneficial microbes improves seed germination, seedling growth, and crop yield. 23,24,11 .The present inventors have previously demonstrated that soil application of cell-free filtrates of the beneficial fungus Trichoderma harzianum and fungal phytopathogens (e.g., Alternaria alternata and Penicillium aurantiogriseum) promotes root growth and improves the yield of pepper plants grown under optimal irrigation conditions. 25. Therefore, cell-free filtrates of beneficial and phytopathogenic fungi can be used as biostimulants to improve crop yield, as described in international patent application WO 2011 / 135121 A2 . Compositional analyses of these cell-free fungal filtrates revealed the presence of volatile organic compounds (VOCs), some of which have been shown to promote plant growth. Thus, the present invention proposes a solution to the technical problems identified above, especially with respect to methods for improving the yield and efficiency of plant cultivation under abiotic stress conditions.particularly high salinity and / or water scarcity. This solution is based on a method that combines two essential technical characteristics: the application of a biostimulant to the aerial parts of the plant and the selection of the specific biostimulant as a cell-free filtrate obtained from the cultivation of fungi belonging to the Trichoderma genus. Description of the Invention In one aspect, the present invention provides a method for improving the method for increasing plant tolerance to abiotic stress comprising: provide the plant with resistance to abiotic stress,where the CF biostimulant composition or product according to the present invention comprises a cell-free culture filtrate of one or more fungi of the genus Trichoderma. In a further aspect, the invention relates to the above method, wherein the cell-free culture filtrate of one or more fungi of the genus Trichoderma, comprises one or more volatile organic compounds emitted into the culture medium by the microorganism(s), where the volatile organic compounds are selected from the group comprising: ethanol, 1-propanol, 1-propanol, 2-methyl, 1-butanol-3-methyl, 1-butanol, 2-methyl, 3-methyl-1-pentanol, 1-butanol, 3-methyl-, acetate, 1-butanol, 2-methyl-, acetate, 2-heptanol, 2-nonanol, 2-undecanol, benzaldehyde-2-methyl, 2,4-dimethyl-1-heptene, toluene, 2-phenylethyl alcohol, phenol, 4-ethyl, 2-acetyl-3-methylthiophene, benzene-1,3-bis(1,1-dimethylethyl), 2,5-di-tert-butyl-1,4-benzoquinone, ethyl acetate, acetic acid, propenoic acid ethyl ester, isobutyl acetate,butanoic acid, ethyl ester, butanoic acid, 2-methyl-ethyl ester, 2-pentanone, 2- heptanone, butyrolactone, 2-heptanone-4- methyl, 2-heptanone-4,6-dimethyl, 2- nonanone, (+)-isomenthol, citronellol, citral, cis-beta-farnesene, betahumulene, alpha- bisabol, beta-selinene, alpha-gurjunene and alpha-cedrene. In another aspect of the invention, the method as defined above is characterized in that the biostimulant composition comprises a cell-free filtrate from the culture of microorganisms of the genus Trichoderma comprising one or more of: Trichoderma afroharzianum, Trichoderma asperelloides (strain T203), Trichoderma asperellum (strain T-203), Trichoderma atroviride (strains IMI 206040, MUCL 45632, P1), Trichoderma ghanense, Trichoderma hamatum (strains DIS 219b, GD12), Trichoderma harzanium (strains 1295-22, ALL-42, AK20G, CECT2413, GT3-2, NF-9, OTPB3, T-1, T-22, T-39, T-203), Trichoderma longibrachiatum, Trichoderma parareesei, Trichoderma virens (strains G-6, G-6-5, G-11, PDBCTVs 12,PDBCTVs 13, T3, Tv29.8, ^ppt1), Trichoderma viridae (strain T-67, TV 97) and / or Trichoderma yunnanense. In another aspect of the invention, the application of the biostimulant composition on the aerial parts of the plants comprises covering at least 3%, 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 99% or 100% of the total surface of the aerial parts of the plant with said biostimulant composition. In another aspect of the invention, it is contemplated that the application of the biostimulant product to the plant is carried out to the aerial parts of the plant that comprise: stem(s), hypocotyls, cotyledons, leaf(s), flower(s), fruit(s) and / or seed(s). In another aspect of the invention, as defined in previous paragraphs, applying the biostimulant composition to the aerial parts of the plant comprises: watering, spraying, spreading, atomizing, pulverizing, spraying under pressure by sprinkling,micro-spraying or misting. In another aspect of the invention described above, the application of the biostimulant composition to the aerial parts of the plant is carried out 1-4 times per month. In another aspect of the invention, the method for improving the crop yield of a plant comprises abiotic stress conditions selected from the group consisting of: cold temperature, freezing, cooling, heat or high temperature, drought, reduction of irrigation input or water stress, salinity or high electrical conductivity in soil or irrigation water, high light intensity, low light intensity, ozone,high concentration of heavy metals in soil and / or irrigation water, and any combination thereof. Another aspect of the invention provides that the method can be applied under abiotic stress conditions that include a combination of drought and / or salinity stress. In another aspect of the invention, it is contemplated that the method defined in previous paragraphs is applicable to plants selected from the group comprising: wheat, rye, oats, buckwheat, chia, flax, rice, corn, potato, sweet potato, tomato, pepper, eggplant, lettuce, lamb's lettuce, endive, escarole, arugula and other leafy vegetables, zucchini, cucumber, cauliflower, broccoli, onion, garlic, carrot, tiger nut, ginger, strawberry, blueberry, raspberry, blackberry, cherry, currant and other red fruits, artichoke, melon, watermelon, pumpkin, green legumes, chickpea, lentil, bean, soybean, cotton, sunflower, tobacco, oregano, thyme, lavender, alfalfa, basil, mint, parsley, peach tree, almond tree, plum tree,nectarine, apricot and other species of trees of agricultural interest of the genus Prunus sp., vine, avocado, mango, custard apple, papaya, kiwi, medlar, guava, carambola, pomegranate, banana, mandarin, orange, lemon, grapefruit, olive, walnut,hazelnut and / or cashew. Another aspect of the invention contemplates that the method defined in previous paragraphs is applicable to a tomato plant of the species Solanum lycopersicum L. Another aspect of the invention contemplates how to improve the crop yield of a plant: increase the number of fruits per plant and / or increase the total weight of fruits per plant and / or increase the weight and size of the fruits and / or reduce the amount of water and / or nutrients necessary to obtain the same amount of fruits as in plants grown under normal conditions. It is also an aspect of the present invention that the biostimulant composition used in the method of the invention also comprises other additional active compounds selected from the group consisting of: pesticides, plant hormones, insecticides, bactericides, fungicides, antibiotics, proteins, peptides, amino acids,organic acids and / or carbohydrates and / or an agriculturally acceptable carrier. It is also an aspect of the present invention that the method for improving the crop yield of a plant under abiotic stress conditions described in the preceding paragraphs is applicable to plant growth under field conditions or in a pot in a greenhouse. A further aspect of the present invention is also a method for reversing or preventing the alteration of the expression of genes related to primary and secondary carbohydrate, lipid and amino acid metabolism, hormone production and signaling, RNA synthesis and processing, protein synthesis, modification and stabilization, solute and nutrient transport, and cell wall organization in plants subjected to water stress or drought conditions, wherein said method is characterized in that it comprises, as in the method described in the preceding paragraphs,growing a plant in a substrate ^^ ... No.2 of plants grown under water stress conditions, comprising: growing a plant in a plant an effective amount of a biostimulant composition or product,also referred to herein as “CF biostimulant composition or product”, to provide the plant with resistance to abiotic stress, where the CF biostimulant composition or product according to the present invention comprises a cell-free culture filtrate of one or more fungi of the genus Trichoderma. Figures Figure 1. Number of commercial (A) and non-commercial (B) fruits, and total commercial fruit production (C) of tomato plants grown under CNT, WS60 and WS30 irrigation conditions with or without foliar application of CF biostimulant product of 3 dilutions (D1, D2, D3) of Trichoderma harzianum . Plants treated with W-MS and untreated plants (NT) were used as negative controls. Data are the mean of 10 replicates and error bars represent standard deviations. Different letters indicate significant differences at P < 0.05 (LSD test). Figure 2. Average fruit weight of tomato plants grown under CNT irrigation conditions,WS60 and WS30 with or without foliar application of 3 dilutions (D1, D2, D3) of Trichoderma harzianum biostimulant CF. Plants treated with W-MS and untreated plants (NT) were used as negative controls. Data are the mean of 10 replicates and error bars represent standard deviations. Different letters indicate significant differences at P < 0.05 (LSD test). Figure 3. Volume of water required to obtain 1 kg of commercial fruits per tomato plant grown under CNT irrigation conditions, WS60 and WS30 with or without foliar application of 3 dilutions (D1, D2, D3) of Trichoderma harzianum biostimulant CF. Plants treated with W-MS and untreated plants (NT) were used as negative controls. Data are the mean of 10 replicates, and error bars represent standard deviations. Different letters indicate significant differences at P < 0.05 (LSD test). Figure 4. Nitrogen (A),Phosphorus (B) and potassium (C) required to obtain 1 kg of commercial fruits per tomato plant, grown under CNT, WS60 and WS30 irrigation conditions with or without foliar application of 3 dilutions (D1, D2, D3) of Trichoderma harzianum biostimulant CF. Plants treated with W-MS and untreated plants (NT) were used as negative controls. Data are the mean of 10 replicates and error bars represent standard deviations. Different letters indicate significant differences at P < 0.05 (LSD test). Figure 5. Number of commercial (A) and non-commercial (B) fruits, and total commercial fruit production (C) of tomato plants grown under CNT and SS40 irrigation conditions with or without foliar application of 3 dilutions (D1, D2, D3) of Trichoderma harzianum biostimulant CF.D3) of Trichoderma harzianum. Plants treated with W-MS and untreated plants (NT) were used as negative controls. Data are the mean of 10 replicates, and error bars represent standard deviations. Different letters indicate significant differences at P < 0.05 (LSD test). Figure 6. Average fruit weight of tomato plants grown under CNT and SS40 irrigation conditions with or without foliar application of CF biostimulant product of 3 dilutions (D1, D2, D3) of Trichoderma harzianum. Plants treated with W-MS and untreated plants (NT) were used as negative controls. Data are the mean of 10 replicates, and error bars represent standard deviations. Different letters indicate significant differences at P < 0.05 (LSD test). Figure 7. Volume of water required to obtain 1 kg of commercial fruits per tomato plant grown under CNT and SS40 irrigation conditions with or without foliar application of 3 dilutions (D1, D2, D3) of Trichoderma harzianum biostimulant CF. Plants treated with W-MS and untreated plants (NT) were used as negative controls. Data are the mean of 10 replicates and error bars represent standard deviations. Different letters indicate significant differences at P < 0.05 (LSD test). Figure 8. Nitrogen (A), phosphorus (B) and potassium (C) required to obtain 1 kg of commercial fruits per tomato plant, grown under CNT and SS40 irrigation conditions with or without foliar application of 3 dilutions (D1, D2, D3) of Trichoderma harzianum biostimulant CF.D3) of Trichoderma harzianum. W-MS-treated plants and untreated (NT) plants were used as negative controls. Data are the mean of 10 replicates, and error bars represent standard deviations. Different letters indicate significant differences at P < 0.05 (LSD test). Figure 9: Functional categorization of the 687 “golden genes” identified by comparing the differences between the transcriptomes of the groups [WS (plants grown under water stress conditions) vs. OI (well-irrigated plants)] and [WS+CF (plants grown under water stress conditions + foliar application of CF biostimulant composition) vs. WS (plants grown under water stress conditions)]. The graph shows the number of overexpressed and underexpressed “golden genes” classified by functional categories according to MAPMAN (https: / / mapman.gabipd.org / ) in the WS+CF vs. WS comparison. Figure 10A: Represents a diagram of the 2C-methyl-D-erythritol-4-phosphate (MEP) pathway for the synthesis of plastidial isoprenoids in the plant. Figure 10B: Represents a diagram of the mevalonic acid pathway,(MVA) for the synthesis of cytosolic isoprenoids in plants. Detailed description of the invention As a result of an intense research process, the inventors of the present invention have managed to design a method for improving the crop performance of a plant under stress conditions. that is, a method for increasing the tolerance of plants to abiotic stress and thus reversing the harmful processes that occur in the growth and development of the plant under such circumstances. As used in this patent application, the term "abiotic stress" refers to the effect caused by non-biological external factors, such as rainfall, high or low temperatures, drought, reduction in water supply, wind, salinity, soil problems, chemicals, etc., that is, external factors,in which proper plant development is impeded, potentially causing detrimental effects on plant growth and development performance. Thus, according to the present invention, abiotic stress comprises low temperatures, cold temperatures resulting in freezing, cooling, heat or high temperatures, drought, reduction of irrigation input or water stress, salinity or high electrical conductivity in soil or irrigation water, high light intensity, low light intensity, ozone, high concentration of heavy metals in soil and / or irrigation water, and any combination of the aforementioned conditions. These external factors directly affect plant metabolism, including photosynthesis, respiration, solute transport, translocation, protein synthesis, nutrient assimilation, tissue differentiation, formation of carbohydrates, lipids, plant structural substances, and the different stages of crop development.which causes significant yield losses. As is well known, under conditions of water stress, for example, plants react by modulating their transcription and hormonal signaling machinery, which allows them to make metabolic adjustments to cope with low water availability. Biochemical and cellular mechanisms such as water / ion uptake and transport, redox homeostasis, reactive oxygen species (ROS) scavenging, osmoregulation, and membrane protection are accompanied by physiological responses such as the regulation of stomatal opening, root development, and protection of the photosynthetic machinery, which translates, among others, into a reduction in the chlorophyll and carotenoid content of plants. According to the results of the experimental work carried out by the authors of the present invention,The foliar application of the CF biostimulant composition as defined in the present invention is capable of preventing the alteration of the expression of numerous genes or "reversing" their expression when the plant is subjected to water stress, such that it contributes positively to alleviating the deficiencies developed in the plant during its cultivation in such conditions. The researchers of the present invention have determined that the foliar application of the CF biostimulant composition of the invention to plants suffering from water stress largely prevents the alteration of gene expression caused by water stress. Such genes are related to primary (carbohydrates, lipids and amino acids) and secondary metabolism, hormone production and signaling, RNA synthesis and processing, protein synthesis, modification and stabilization, solute and nutrient transport, cell wall organization,etc. (Figure 9). Specifically, it has been confirmed that the DXS2 and HMGR1 genes with SEQ ID No. 1 and SEQ. ID No. 2, respectively, are not differentially expressed after the application of the CF biostimulant composition when the plant is grown under optimal irrigation conditions. However, their expression is negatively affected when the plant is subjected to water stress or "suboptimal" irrigation conditions. The negative effect of drought on the expression of these genes is largely avoided by foliar application of the CF biostimulant composition. These two genes turn out to be essential for the plant to carry out vital growth functions. In the plant, plastidial isoprenoids such as photosynthetic pigments (e.g., chlorophylls and carotenoids), tocopherols, gibberellins, abscisic acid, cytokinins, plastoquinones, etc. are metabolites involved in basic functions such as respiration and photosynthesis.cell division, photoprotection, nutrient uptake, etc. and are synthesized through the 2C-methyl-D-erythritol-4-phosphate (MEP) pathway. The DXS2 gene with SEQ ID. No.1 catalyzes the step that limits metabolic flow through the MEP pathway, thereby limiting the functioning of the MEP pathway for the synthesis of these essential metabolites. (Figure 10A). The expression of this gene (SEQ ID No. 1) is regulated by transcriptional and post-translational mechanisms. On the other hand, the production of cytosolic isoprenoids in the plant, such as sterols, brassinosteroids, polyprenols, triterpenes, cytokinins, etc., are synthesized through the mevalonic acid pathway (MVA). The HMGR1 gene with SEQ ID No.2 catalyzes the rate-limiting step of metabolic flux toward the mevalonate (MVA) pathway and therefore,from the production of cytosolic isoprenoids. (Figure 10B). The HMGR1 gene with SEQ ID No. 2 is therefore an important determinant of plant growth and its expression is also transcriptionally regulated. The authors of the present invention have been able to verify that the application of the CF biostimulant composition to plants grown under water stress conditions prevents the reduction in the expression of the aforementioned genes, DXS2 with SEQ ID No. 1, and HMGR1 with SEQ ID No. 2 induced by drought, such that the effect produced by the CF biostimulant composition manages to reverse the effect produced by the drought and thus manages to increase photosynthesis, growth and yield of the plants grown under such conditions. The method of the invention is applicable both in field conditions and in a greenhouse pot. Therefore,The invention is intended for improving the cultivation performance of horticultural plants and woody plants. Non-limiting examples of horticultural and woody plants that can benefit from the method of the present invention are: wheat, rye, oats, buckwheat, chia, flax, rice, corn, potato, sweet potato, tomato, pepper, eggplant, lettuce and other leafy vegetables, zucchini, cucumber, cauliflower, broccoli, onion, garlic, carrot, tiger nut, ginger, strawberry, and other red fruits, artichoke, melon, watermelon, pumpkin, green legumes, chickpea, lentil, bean, soybean, cotton, sunflower, tobacco, oregano, thyme, lavender, alfalfa, basil, mint, parsley, peach tree and other species of trees of agronomic interest of the genus Prunus sp., vine, avocado, mango, custard apple, papaya, kiwi, medlar, guava, star fruit, pomegranate, banana tree, mandarin tree, orange tree, lemon tree, grapefruit, olive, walnut,hazelnut and / or cashew. Preferably, the method of the present invention is intended for improving the yield of tomato plants of the species Solanum lycopersicum L. As defined above, the method of the present invention is directed towards improving the crop yield of plants and as such comprises increasing the number of fruits per plant and / or increasing the total weight of fruits per plant and / or increasing the weight and size of the fruits and / or reducing the amount of water and nutrients necessary to obtain a given number of fruits. Such improvements may be determined in comparison with the crop yield in the same plants without them being subjected to the method of the present invention, which comprises growing a plant in a plant substrate in the presence of the nutrients necessary for the growth and development of the plant, and applying an effective amount of a biostimulant composition to the aerial parts of the plant,where the biostimulant composition comprises a cell-free culture filtrate of one or more fungi of the genus Trichoderma. Therefore, the method of the present invention is mainly characterized by growing a plant and applying an effective amount of a biostimulant composition to the aerial parts of said plant during its growth. Said composition, called CF biostimulant composition, is characterized in that it is the result of growing a microorganism of the genus Trichoderma in an appropriate culture medium and removing this microorganism from the culture medium when the growth of the microorganism has entered the logarithmic growth phase, thus obtaining the composition free of microorganisms, that is, free of cells or microorganism particles. For the purposes of the present invention, the use of a composition resulting from the previous procedure is contemplated,using one or more of the following species and strains of the genus Trichoderma: Trichoderma afroharzianum, Trichoderma asperelloides (strain T203), Trichoderma asperellum (strain T-203), Trichoderma atroviride (strains IMI 206040, MUCL 45632, P1), Trichoderma ghanense, Trichoderma hamatum (strains DIS 219b, GD12), Trichoderma harzanium (strains 1295-22, ALL-42, AK20G, CECT2413, GT3-2, NF-9, OTPB3, T-1, T-22, T- 39, T-203), Trichoderma longibrachiatum, Trichoderma parareesei, Trichoderma virens (strains G-6, G-6-5, G-11, PDBCTVs 12, PDBCTVs 13, T3, Tv29.8, ^ppt1), Trichoderma viridae (strain T-67, TV 97) and / or Trichoderma yunnanense. Thus, the use of Trichoderma harzanium strain CECT2413 is preferably contemplated, the use of CF biostimulant compositions obtainable from said strain and described in patent application WO2017174503 being preferable. Said CF composition is further characterized by not containing cells, that is,be free of any cells and contain parts per billion of one or more volatile organic compounds emitted into the culture medium by the microorganism(s) of the genus Trichoderma, where the volatile organic compounds are selected from the group comprising: ethanol, 1-propanol, 1-propanol, 2-methyl, 1-butanol-3-methyl, 1-butanol, 2-methyl, 3-methyl-1-pentanol, 1-butanol, 3-methyl-, acetate, 1-butanol, 2-methyl-, acetate, 2-heptanol, 2-nonanol, 2-undecanol, benzaldehyde-2-methyl, 2,4-dimethyl-1-heptene, toluene, 2-phenylethyl alcohol, phenol, 4-ethyl, 2-acetyl-3-methylthiophene, benzene-1,3-bis(1,1-dimethylethyl), 2,5-Di-tert-butyl-1,4-benzoquinone, ethyl acetate, acetic acid, propenoic acid ethyl ester, isobutyl acetate, butanoic acid, ethyl ester, butanoic acid, 2-methyl-ethyl ester, 2-pentanone, 2-heptanone, butyrolactone, 2-heptanone-4- methyl, 2-heptanone-4,6-dimethyl, 2-nonanone, (+)- isomenthol, citronellol, citral, cis- beta- farnesene, betahumulene, alpha- bisabol,beta-selinene, alpha-gurjunene and alpha-cedrene. Said composition can be used directly or in diluted form in ^^^^^^^^^^^^^ ^^^^^ ^^^^^ ^^ ^^ ^^ ^^!^ ^^^^^^ ^^^^ aerial parts of the plant. Optionally, said composition can form part of a biostimulant product and can also contain other active ingredients such as: pesticides, plant hormones, insecticides, bactericides, fungicides, antibiotics, proteins, peptides, amino acids, organic acids and / or carbohydrates, commonly known and used in agriculture by those skilled in the art. And finally, it can also contain any of the vehicles accepted in agriculture and well known to those skilled in the art. Examples of agriculturally acceptable carriers include, but are not limited to, adjuvants, diluents, surfactants, conditioning agents, antifreezes, antifoaming agents, thickeners, wetting agents, spreading agents, dispersing agents,emulsifying agents, antimicrobial agents, and the like. The agricultural compositions or products must be in a form acceptable for application to the aerial parts of the plant, so they can be presented in the form of particulate solids, solutions, dispersions, suspensions, or emulsions. One of the most relevant characteristics of the present invention is that, in order to achieve the yield-improving effects, the composition described above must be applied to the aerial parts of the plant to be treated. For these purposes, the aerial part of the plant is understood to be the stems, hypocotyls, cotyledons, leaves, flowers, fruits, and / or seeds. For the application of the composition to be effective in improving the yield of the plant's crop, the application must cover at least 3% of the total surface area of ​​the aerial parts of the plant, that is, it must cover at least 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%,99% or 100% of the total surface area of ​​the aboveground part of the plant being treated. The composition is applied to the aboveground part of the plant by watering, spraying, spreading, atomizing, spraying, pressure spraying, micro-spraying, or nebulizing. There is no limitation on the number of times the composition should be applied to the aboveground part of the plant during cultivation to improve the plant's crop yield, although application is contemplated between 1 and 6 times per month, preferably 1 to 4 times per month, and more preferably 2 to 3 times per month. Unlike existing market proposals that are based on the application of various types of treatments to the seeds to primarily produce an increase in germination vigor, that is, the percentage and speed of germination, in this case,The treatment is applied at a specific growth stage once the various germination phases have been completed, and which visually mostly coincides with the formation of 2 to 4 true leaves until fruiting, when the method of the invention is applied to horticultural plants, and at any time of year when it comes to woody plants. The beneficial effects of the method of the invention under abiotic stress conditions due to reduced water supply translate into a substantial improvement in the crop yield of the plants. Specifically, the method of the invention results in an increase in the total number of commercial fruits per plant compared to plants not treated with the method according to the invention. Said increase, as demonstrated in the experimental part that follows, reaches at least 13%, preferably between 15% and 30%, for example, 16% or 17%, or even greater than 30%.for example 32%. Also under conditions of abiotic stress due to reduced water supply, the method of the present invention can result in an increase in the total number of commercial fruits, as demonstrated in the experimental part, where said increase is at least 15%, preferably between 20% and 30%, specifically 21%, 24% or 26%. Likewise, the yield of plant crops under conditions of reduced water supply can be measured through an increase in the average weight of the fruits, where, as demonstrated below, there is an increase in the average weight of the fruits in the treated plant of 7%. Additionally, the improvement in plant crop yield can be achieved through a reduction in the water required to obtain one kilo of commercial fruits. That is, under normal conditions such as reduced water supply,The plant treated with the method of the invention requires a substantially lower amount of water to produce one kilo of fruit compared to untreated plants. Thus, the reduction in water required to produce one kilo of fruit is at least 10%, preferably between 20 and 30% and even to values ​​higher than 30%, such as 34% or 35%. Similarly, the treated plants, both under normal and drought conditions, perform better efficiency in the use of nutrients, nitrogen (N), phosphorus (P) and potassium (K), reaching the same efficiency values ​​as those achieved in the case of reduced water input. The beneficial effects of the method of the invention under salt stress conditions translate into a substantial improvement in the crop yield of the plants. Specifically,The method of the invention achieves an increase in the total number of marketable fruits per plant compared to plants not treated with the method according to the invention. This increase, as demonstrated in the following experimental section, reaches at least 30%, preferably at least 60%. Thus, under salt stress conditions, the loss of non-marketable fruit was much lower than in untreated plants, with losses of non-marketable fruit only reaching values ​​not exceeding 30% compared to values ​​exceeding 40% in plants grown under normal conditions. As for the total yield of marketable fruit,Losses in treated plants were less than 48% compared to untreated plants, where losses can be quantified at at least 60%. The average fruit weight in plants treated under salt stress conditions reflects an increase in average fruit weight of more than 11% compared to untreated plants grown under the same conditions. Similarly, the reduction in water and NPK required to produce the same amount of fruit is estimated at values ​​of up to 41% and 28%, as illustrated in the practical examples of the invention. Foliar application of a cell-free filtrate based on Trichoderma harzianum CECT2413 to tomato plants Solanum lycopersicum L. under abiotic stress conditions. The research was carried out at the facilities of the "Instituto de Hortofruticultura Subtropical y Mediterránea" (IHSM), located in Algarrobo (Málaga) in an 800 gauge plastic multi-tunnel greenhouse. At the 6-8 true leaf stage, tomato plants of the Macizo F1 variety were transplanted into 17 L pots with a mixture of peat: coconut fiber: vermiculite (45:45:10). After transplanting, the plants were irrigated with a nutrient solution containing the macronutrients NO3- (1.27 mM), NH3 (3.52 mM), CaO (2.31 mM), MgO (0.74 mM), P 2 O 5 (0.48 mM), K2O (2.16 mM) and SO3 (1.11 mM). Regarding micronutrients, the nutrient solution contained B (23.12 µM), Cu (2.36 µM), Fe (67.15 µM), Mn (36.40 µM), Mo (1.042 µM) and Zn (3.82 µM). The electrical conductivity (EC) was 1.5 dS m-1 and a pH of 6.73. Fifteen days after transplanting, tomato plants were subjected to two types of abiotic stresses that were maintained until the end of the experiment. (i) 40 mM (SS40) sodium chloride (NaCl) and (ii) reduction to 60% (WS60) and 30% (WS30) of the water volume used for 100% irrigation. Plants without NaCl treatment or reduction in water content were used as controls (CNT). The electrical conductivity of the SS40 irrigation water was 5.78 dS m -1and a pH of 6.63. Ten plants were established per stress condition and cell-free (CF) fungal treatment. The fungal species used to obtain the cell-free (CF) biostimulant composition used in the trial on fruit yield and quality of tomato plants grown under stress conditions due to reduced water supply and salinity was Thrichoderma harzianum "#$^^^^^^^^^%&%# 2413). Obtaining CF biostimulant composition To obtain the biostimulant composition based on fungal cultures of Thrichoderma harzianum "#$^ code CECT 2413), the fungi were first grown in Petri dishes containing 0.22% (w / v) Murashige & Skoog solid basal medium with vitamins (PhytoTech, code number '(^!^ MS), 3% (w / v) D-sucrose (PanReac AppliChem, code number A3925) and 0.8% (w / v) vegetable agar (Duchefa Biochemie, code number P1001), pH adjusted to 5.74 and sterilized.Cultures were maintained at 28 ˚C for 7 days in the dark. Colonies were then transferred to 500 mL Erlenmeyer flasks containing 200 mL of sterilized liquid culture medium (0.22% w / v DM and 3% w / v D-sucrose). These cultures were maintained for 7 days on a shaker at 150 rpm and 28 ˚C in the dark and transferred to 2 L Erlenmeyer flasks containing 900 mL of liquid culture medium. The cultures were placed on a shaker and incubated at 28 ˚C under continuous shaking (150 rpm) for 3 days in the dark, after which the fungal mycelium was removed using Whatman No. 1 filter paper. The resulting filtrate was sterilized using a 0.22 )m Millipore membrane filter and stored at 4 ˚C awaiting further use.Foliar application of biostimulant products The fungal CF biostimulant products were sprayed onto plant leaves at three different dilutions in water: undiluted, 1:2, and 1:4 dilutions (D1, D2, and D3, respectively). Untreated plants (NT) and plants treated with a growth medium based on MS (W-MS) were used as controls. W-MS contained a 1:6 dilution of MS and 0.036 g / L of D(+)-glucose (Carlo Erba, code number 454337) and D(-)-fructose (VWR, code number 103674Y). Applications were made in four different phases: i) 2-4 leaves ^^^^^^^^^^^ ii) after ^^^^^^^^^^^ iii) during *^^^^^^^^^^^ iv) at fruiting time. Results Foliar application of Trichoderma fungal CF biostimulant products or compositions increases fruit production in plants grown under conditions of reduced water input.Figures 1-3 show the fruit production parameters of plants treated and untreated with the CF biostimulant products or compositions of T. harzianum grown under mild and severe water stress conditions (WS60 and WS30, respectively). Statistically significant differences were found in both the type of stress and the application. In plants grown under the mild irrigation regime WS60, foliar application of D1, D2, and D3 increased the total number of marketable fruits per plant by approximately 16, 13, and 17%, respectively, compared to the control treatments NT and W-MS (Fig. 1A). Furthermore, foliar application of D2 and D3 increased total marketable fruit production by 15 and 21%, respectively, compared to the NT and W-MS treatments (Fig. 1C).Under CNT conditions, plants treated with D1 and D2 increased the average fruit weight by 7% compared to NT and W-MS combinations (Fig. 2). Regarding the volume of water needed to obtain 1 kg of commercial fruits, it is worth highlighting the significant reduction when applying D2 and D3 compared to NT and W-MS under WS60 conditions (13 and 20% reduction, respectively) and compared to D2 and D3 under CNT conditions (35 and 34% of ^^^^^^^^^^^^^^^^^^^^^^^^^^+^",^^-^.+^^^^^^^^^^^^^^^^^^^^^*^^ / ^^^^^^^^^ a better efficiency of use of NPK nutrients (Fig. 4). In plants grown under the WS30 irrigation regime, foliar application of D1 and D2 increased the total number of commercial fruits by 32% and 26%, respectively, compared to the control treatments NT and W-MS (Fig. 1A). In plants grown under the WS60 irrigation regime, foliar application of D1 and D2 increased the total number of commercial fruits by 32% and 26%, respectively, compared to the control treatments NT and W-MS (Fig. 1A). D1, D2 and D3 increased the total number of commercial fruits by 12%, 15% and 20% respectively.Furthermore, WS30 treatments increased total marketable yield by 26 and 24%, respectively, compared to the NT and W-MS control treatments (Fig. 1C). Foliar application of D1 and D2 reduced the number of unmarketable fruits by 40% (Fig. 1B). Foliar application of the fungal CF biostimulants increased fruit production in plants grown under salt stress conditions. The production parameters of plants grown under SS40 conditions are presented in Figures 5-8. Regarding the number of marketable fruits, D1- and D2-treated plants produced 67 and 31% more marketable fruits than NT and W-MS-treated plants (negative controls under the same stress conditions), respectively (Fig. 5A).Losses in D1- and D2-treated plants (15 and 31%, respectively) were significantly lower than in NT and W-MS controls (54 and 45%, respectively) compared to non-stressed plants (Fig. 5A). In terms of total marketable fruit yield, losses in D1- and D2-treated plants (43% and 48%, respectively) were lower than in NT and W-MS plants (65% and 61%, respectively) compared to non-stressed plants (Fig. 5C). The positive results at D1 and D2 dilutions were also reflected in an increase in average fruit weight compared to NT and W-MS under SS40 of up to 11 and 13%, respectively (Fig. 6), as well as in a reduction in water and NPK required to produce the same amount of fruit of up to 41 and 28% (Figs. 7 and 8).Consequently, under salinity stress, the ability to reduce the amount of water and nutrients necessary to produce commercial quality tomato fruits and improve yield using these biostimulant products is proven. In conclusion, foliar application of CF biostimulant products based on microorganisms of the genus Trichoderma, and in particular, T. harzianum, improves fruit production in tomato plants grown under stress conditions by reducing water and salinity input and reduces the amount of water and nutrients necessary to produce the same amount of fruit as untreated plants. Leaf transcriptomics of the experiment described in example 1 Leaf transcriptomics by RNA sequencing was carried out using leaves of plants grown under CNT and WS60 irrigation conditions subjected to D3 dilution and W-MS, as described in example 1. RNA was extracted using the TRIzol-chloroform method.Specifically, 50 mg of leaf samples were mixed with TRIzol reagent and centrifuged for 10 min at 4°C and 12,000 rpm. The supernatants were removed and mixed with chloroform. After 3 min at room temperature, the samples were centrifuged for 15 min at 4°C and 12,000 rpm. The supernatants were mixed with isopropanol and incubated at room temperature for 10 min. The samples were then centrifuged for 10 min at 4°C and 12,000 rpm. The pellet was recovered and mixed with 75% (V / V) ethanol and then centrifuged for 5 min at 4°C and 7500 rpm. After removing the supernatant and evaporating the ethanol, the samples were resuspended in water. DNA digestion was performed using TURBO™ DNAse (Thermo Fisher Scientific, Cat. No. AM2238). RNA cleanup was then performed using the phenol:chloroform:NaAc method. Specifically, samples were mixed with phenol (pH 8) and chloroform:isoamyl alcohol (24:1).The samples were then centrifuged for 10 min at 4°C and 13,000 rpm. The supernatant was mixed with 3 M sodium acetate and absolute ethanol. After 45 min at -80°C, the samples were centrifuged for 15 min at 4°C and 13,000 rpm. The pellet was recovered, and 70% (V / V) ethanol was added. After centrifugation for 15 min at 4°C and 13,000 rpm, the pellet was recovered. After evaporation, the samples were resuspended in water. Quality control was performed using the agarose gel, NanoDrop, and Qubit methods. Only samples with no signs of degradation in agarose gel, A260 / A280 and A260 / A230 ratios > 2 in NanoDrop, and Qubit concentrations above the company's requirements were sent to Sistemas Genómicos, which was responsible for RNA sequencing. The data obtained were transferred for bioinformatics analysis using the Supercomputing and Bioinformatics Service of the Bioinnovation Center, located at the University of Malaga.Sequence quality control was performed using FastQC. In this step, several quality metrics were assessed, such as per-base sequence quality, GC content, sequence duplication levels, and overrepresented sequences. Any detected anomalies were addressed to ensure the reliability of downstream analyses. Fastp and Ribodetector were used for read preprocessing. Fastp facilitated adapter trimming, quality filtering, and other preprocessing steps to improve read quality. Ribodetector was used to identify and remove potential ribosomal RNA contaminants that could interfere with downstream analyses. The reference genome was indexed using BWA, a widely used alignment tool. Reads were then mapped to the reference genome using Bowtie2 and Sambamba.This alignment step ensured accurate read placement, allowing for subsequent analyses such as expression quantification and differential expression analysis. Expression quantification was performed using Sam2counts, which consisted of counting the number of reads aligned to each gene. This provided quantitative information on gene expression levels under different experimental conditions or sample groups, thereby determining when a gene is overexpressed or underexpressed. Differential expression analysis was performed using DESeq2, a powerful tool for detecting differentially expressed genes across conditions.By comparing expression levels across conditions, taking into account variability and experimental design, DESeq2 identified genes with statistically significant changes in expression, providing insight into the biological processes underlying the treatments or experimental conditions. Gene functional classification was performed using the MAPMAN program (https: / / mapman.gabipd.org / ). A first group of genes was identified whose expression in leaves is altered by foliar application of the CF biostimulant composition, resulting from a comparison of transcriptomes between the following groups: WS+CF (plants grown under water stress conditions + foliar application of CF biostimulant composition) vs. WS (plants grown under water stress conditions), and OI+CF (well-irrigated plants + foliar application of CF biostimulant composition) vs. OI (well-irrigated plants).From the comparison made between the transcriptomes of both groups, a group of genes, called "CF genes" is defined, which comprises the coincidence of 306 differentially expressed genes (DEGs), which, regardless of the cultivation conditions of the plant, their expression is altered by the foliar application of the CF biostimulant composition of the invention. Additionally, a list of genes potentially involved in the response of the plant grown under water stress conditions to the foliar application of the CF biostimulant composition of the invention was prepared, resulting from the comparison of the transcriptomes between the following groups: - WS (plants grown under water stress conditions without foliar application of the CF biostimulant composition) vs.OI (well-irrigated plants without foliar application of the CF biostimulant composition), and - WS+CF (plants grown under water stress conditions + foliar application of CF biostimulant composition) vs. WS (plants grown under water stress conditions without foliar application of the CF biostimulant composition). From the comparison made between both groups, 687 genes, called "golden genes", were identified that are differentially and inversely expressed in both groups, which shows that foliar application of the CF biostimulant composition of the invention to stressed plants "reverses" or prevents the alteration of the expression of numerous genes in plants grown under water stress conditions. Of these 687 so-called "golden genes", the genes with SEQ ID No. 1 (DXS2 gene) and SEQ. ID No. 2, (HMGR1 gene) stand out.The alteration of the expression of these genes by the foliar application of the CF biostimulant composition as defined in the present invention requires that the plant be subjected to water stress. In conclusion, based on the previous experimental work it has been possible to deduce that the foliar application to plants suffering from water stress of a CF biostimulant composition comprising a cell-free culture filtrate of one or more fungi of the genus Trichoderma, implies a reversal or a significant reduction of the transcriptional differences existing between a well-irrigated plant and a plant grown under water stress conditions. Specifically, it has been confirmed that the application of the CF biostimulant composition prevents the reduction in the expression of the DXS2 genes with SEQ. ID. No. 1 and HMGR1, with SEQ. ID. No. 2 induced by drought. That is, the application of the CF biostimulant composition prevents the reduction in the expression of the DXS2 genes with SEQ. ID. No.1 and HMGR1, with SEQ.ID.No.2 induced by the sequence, thus avoiding the reduction of plastidial activity and the cytosolic route of isoprenoid production.

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Claims

CLAIMS 1. A method for improving the crop performance of a plant under abiotic stress conditions comprising: - growing a plant in a plant substrate in the presence of ^^^^^^^^^^^ and - applying to the aerial parts of the plant an effective amount of a biostimulant composition to provide the plant with resistance to abiotic stress, wherein the biostimulant composition comprises a cell-free culture filtrate of one or more fungi of the genus Trichoderma.

2. The method according to claim 1, wherein the cell-free culture filtrate of one or more fungi of the genus Trichoderma comprises one or more volatile organic compounds emitted into the culture medium by the microorganism(s), wherein the volatile organic compounds are selected from the group comprising: ethanol, 1-propanol, 1-propanol, 2-methyl, 1-butanol-3-methyl, 1-butanol, 2-methyl, 3-methyl-1-pentanol, 1-butanol, 3-methyl-, acetate, 1-butanol, 2-methyl-, acetate, 2-heptanol,2-nonanol, 2-undecanol, benzaldehyde-2-methyl, 2,4-dimethyl-1-heptene, toluene, 2-phenylethyl alcohol, phenol,4-ethyl, 2-acetyl-3-methylthiophene, benzene-1,3- bis (1,1-dimethylethyl), 2,5-di- tert-butyl-1,4-benzoquinone, ethyl acetate, acetic acid, propenoic acid ethyl ester, isobutyl acetate, butanoic acid, ethyl ester, butanoic acid, 2-methyl-ethyl ester, 2-pentanone, 2-heptanone, butyrolactone, 2- heptanone-4-methyl, 2-heptanone-4,6-dimethyl, 2-nonanone, (+)- isomenthol, citronellol, citral, 3. The method according to any one of the preceding claims, characterized in that the microorganisms of the genus Trichoderma comprise one or more of: Trichoderma afroharzianum, Trichoderma asperelloides (strain T203), Trichoderma asperellum (strain T-203), Trichoderma atroviride (strains IMI 206040, MUCL 45632, P1), Trichoderma ghanense, Trichoderma hamatum (strains DIS 219b, GD12),Trichoderma harzanium (cepas 1295-22, ALL-42, AK20G, CECT2413, GT3-2, NF-9, OTPB3, T-1, T-22, T-39, T-203), Trichoderma longibrachiatum, Trichoderma parareesei, Trichoderma virens (cepas G-6, G-6-5, G-11, PDBCTVs 12, PDBCTVs 13, T3,Tv29.8, ^ppt1), Trichoderma viridae (strain T-67, TV 97) and / or Trichoderma yunnanense.

4. The method according to any of the preceding claims wherein applying the biostimulant composition to the aerial parts of the plants comprises covering at least 3%, 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 99% or 100% of the total surface of the aerial parts of the plant with the biostimulant composition.

5. The method according to any of the preceding claims wherein the aerial parts of the plant comprise: stem(s), hypocotyls, cotyledons, leaf(s), flower(s), fruit(s) and / or seed(s).

6. The method according to any of the preceding claims, wherein applying the biostimulant composition to the aerial parts of the plant comprises: watering, spraying, spreading, atomizing, spraying, pressure spraying, micro-spraying, or nebulizing. 7.The method according to any one of the preceding claims, wherein the application of the biostimulant composition to the aerial parts of the plant is carried out 1-4 times a month.

8. The method according to any one of the preceding claims, wherein the abiotic stress conditions are selected from the group consisting of: cold temperature, freezing, cooling, heat or high temperature, drought, reduction of irrigation input or water stress, salinity or high electrical conductivity in soil or irrigation water, high light intensity, low light intensity, ozone, high concentration of heavy metals in soil and / or irrigation water and any combination thereof.

9. The method according to claim 8, wherein the abiotic stress is a combination of drought and / or salinity. 10.The method according to any of the preceding claims, wherein the plant is selected from the group comprising: wheat plant, rye, oats, buckwheat, chia, flax, rice, corn, potato, sweet potato, tomato, pepper, eggplant, lettuce, lamb's lettuce, endive, escarole, arugula, zucchini, cucumber, cauliflower, broccoli, cabbage, onion, garlic, carrot, tiger nut, ginger, strawberry, blueberry. raspberry, blackberry, cherry, currant, strawberry tree, artichoke, melon, watermelon, pumpkin, green legumes, chickpea, lentil, bean, kidney bean, soybean, cotton, sunflower, tobacco, oregano, thyme, lavender, alfalfa, basil, mint, parsley, spearmint, peach tree, almond tree, plum tree, nectarine tree, apricot tree, vine, avocado, mango, custard apple, papaya, kiwi, medlar tree, guava, star fruit, pomegranate tree, banana tree, mandarin tree, orange tree, lemon tree, lime tree, grapefruit tree, olive tree, walnut tree, hazelnut tree and / or cashew tree.

11. The method according to claim 10, wherein the plant is a tomato plant of the species Solanum lycopersicum L. 12.

13. The method according to any of the preceding claims, wherein improving the crop yield of a plant comprises: increasing the number of fruits per plant and / or increasing the total weight of fruits per plant and / or increasing the weight and size of the fruits and / or reducing the amount of water and nutrients needed to obtain the same yield as plants grown under normal conditions.

14. The method according to any of the preceding claims, wherein the biostimulant composition further comprises other additional active compounds selected from the group consisting of: pesticides, plant hormones, insecticides, bactericides, fungicides, antibiotics, proteins, peptides, amino acids, organic acids and / or carbohydrates.

15. The method according to any of the preceding claims, wherein the biostimulant composition further comprises an agriculturally acceptable carrier.The method according to any one of the preceding claims, wherein the plant or a part thereof is grown under field conditions or in a pot in a greenhouse.

16. A method for reversing or preventing the alteration of the expression of genes related to primary carbohydrate, lipid, and amino acid metabolism, secondary metabolism, hormone production and signaling, RNA synthesis and processing, synthesis, modification, and. protein stabilization^ solute and nutrient transport^ and cell wall organization in plants, comprising according to claims 1 to 15: growing a plant in a plant substrate in ^^ ...

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