Title: Organosulfur compounds as plant biostimulants FIELD OF THE INVENTION The disclosure relates to organosulfur containing compositions, in particular di-n- propyl thiosulfonate (PTSO) and di-n-propyl thiosulfinate (PTS), di-methyl thiosulfonate, di-phenyl thiosulfonate and di-n-propyl disulfide. Such compositions are useful for as biostimulants for plants. In particular such compositions may result in increased nutrient use efficiency, increased tolerance to abiotic stress, and/or improved quality characteristics. Compositions comprising said organosulfur compounds are also provided for agricultural use. BACKGROUND OF THE INVENTION Plants are cultivated, ideally, under optimal conditions in order to obtain desired characteristics such as high yield or high quality. Growth conditions may be optimised in terms of root substrate, fertilisation, watering, drainage, light supply, temperature, air movement, air humidity and pest control. During crop and plant production in horticulture, most of mentioned growth conditions are kept under strict control. There are however situations where the control systems are not capable of keeping the optimal parameters under accurate control, for example sudden changes in weather conditions. Examples are alternating sunny and cloudy periods that result in short periods of light and high temperatures or vice versa; sudden temperature changes, such as cold nights that go together with increased heating and low humidity and result in high evaporation rates by the plants; long periods of cloudy weather that result in low photosynthesis rate and high humidity; long periods of sun that result in excess heat and low humidity and high evaporation by the plants. Even during favourable growth periods, growth conditions may occur such that the plant is not able to take up sufficient water and nutrients and grows less rapidly compared to the situation that nutrients and water are present in excess. Plant nutrients are chemical elements and compounds necessary for plant growth and/or plant metabolism. For example, for the growth and development of vascular plants, the following elements are needed, namely carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), potassium (K), sulfur (S), calcium (Ca), magnesium (Mg), boron (B), chlorine (Cl), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), and zinc (Zn). A number of vascular plants also need silicium (Si). In agriculture, nitrogen (N), phosphorus (P), potassium (K), sulfur (S), calcium (Ca), magnesium (Mg), boron (B), chlorine (Cl), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), zinc (Zn) and silicium (Si) are generally provided in fertilisers. These elements can be supplied as relatively pure salts or as complex organic material, e.g. compost, plant waste, (partially) decomposed animal dung from cows, chickens, pigs etc. and are usually supplemented in excess, in order to prevent nutrient limitations. It is clear that during agriculture in the open fields the plants are cultivated under conditions more variable than in greenhouses. Not only temperature, sunlight and root substrate/ air humidity are important abiotic factors, but also wind, frost, salinity, flooding and drought. The described conditions result in abiotic stress for the crops and result in lower yields and/or worse quality parameters of the crops. Abiotic stress is defined as the negative impact of non-living factors on the living organisms in a specific environment. It is clear that some crops and ornamental plants, even under controlled greenhouse conditions, have a lower tolerance to abiotic stress. This is strongly dependent on the species, subspecies hybrid, variant or cultivar. In recent years, the use of plant biostimulants has emerged as a means to improve plant characteristics. According to Du Jardin, P (2012) “The science of plant biostimulants—a bibliographic analysis. Ad hoc Study Report to the European Commission DG ENTR; 2012”, a plant biostimulant is any substance or microorganism applied to plants with the aim to enhance nutrition efficiency, abiotic stress tolerance and/or crop quality traits, regardless of its nutrients content. Biostimulants have the capacity to modify physiological processes of plants in a way that provides potential benefits to growth, development and/or stress response. One object of the present disclosure is to provide plant biostimulants suitable for use in agriculture. SUMMARY OF THE INVENTION The disclosure provides the following preferred embodiments. 1. Use of a compound according to Formula I, or a composition comprising a compound according to Formula I, as a biostimulant for a plant; wherein Formula I is: Formula I, wherein n is 2; wherein one X is -S- and the other X is selected from the group consisting of -S-, - S(O)-, and -S(O) _2- ; and R ¹ and R ² are independently selected from the group consisting of optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroalkyl, optionally substituted heteroaryl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, and optionally substituted heterocycloalkyl, preferably wherein the compound according to Formula I is di-n- propyl thiosulfonate (PTSO), di-n-propyl disulfide, di-methyl thiosulfonate, or di- phenyl thiosulfonate. 2. A method, comprising providing to a plant a compound according to Formula I, or a composition comprising a compound according to Formula I: Formula I, wherein n is 2; wherein one X is -S- and the other X is selected from the group consisting of -S-, - S(O)-, and -S(O) _2- ; and R ¹ and R ² are independently selected from the group consisting of optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroalkyl, optionally substituted heteroaryl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, and optionally substituted heterocycloalkyl, preferably wherein the compound according to Formula I is di-n- propyl thiosulfonate (PTSO), di-n-propyl disulfide, di-methyl thiosulfonate, or di- phenyl thiosulfonate. Preferably the method is for increasing the growth rate, development, yield, and/or harvest of a plant. The method may also increase the vigor of a plant. Preferably the method is for increasing nutrient use efficiency, increasing tolerance of a plant to abiotic stress, improving the quality characteristics of a plant, and/or increasing the availability of nutrients retained in soil or in the rhizosphere for a plant 3. The use or method according to any one of the preceding embodiments, wherein R ¹ and R ² are independently selected from the group consisting of optionally substituted alkyl, and optionally substituted aryl. 4. The use or method according to any one of the preceding embodiments, wherein R ¹ and R ² are independently selected from C _1-6 alkyl, and phenyl; wherein the phenyl group is optionally substituted with C _1-3 alkyl or C _1-3 alkoxy; wherein preferably R ¹ and R ² are independently selected from methyl, ethyl, n- propyl, n-butyl, phenyl, p-tolyl, and 4-methoxyphenyl. 5. The use or method according to any one of the preceding embodiments, wherein R ¹ and R ² are identical. 6. The use or method according to any one of embodiments 1 to 4, wherein the compound according to Formula I is selected from the group consisting of di-n- propyl thiosulfonate (PTSO), S-methyl methanethiosulfonate, S-phenylbenzene thiosulphonate, di-n-propyl thiosulfinate (PTS), methyl methane thiosulfinate, butyl butane thiosulfinate, methyl propene thiosulfinate, di-n-propyldisulfide, dimethyl disulfide, diethyl disulfide, di-n-butyl disulfide, diphenyl disulfide, di-p- tolyl disulfide, and bis(4-methoxyphenyl) disulfide; wherein preferably the compound according to Formula I is di-n-propyl thiosulfonate (PTSO) or di-n-propyl thiosulfinate (PTS). 7. The use or method according to any one of the preceding embodiments, wherein at least 60 wt%, preferably at least 80 wt%, more preferably at least 95 wt%, of organosulfur compounds in said composition are selected from compounds according to Formula I. 8. The use or method according to any one of the preceding embodiments, wherein when said composition comprises diallyl thiosulfinate, the ratio of the compound or compounds according to Formula I to diallyl thiosulfinate by weight is greater than 0.1 preferably greater than 1 and wherein when said composition comprises diallyl disulfide, the ratio of the compound or compounds according to Formula I to diallyl disulfide by weight is greater than 0.1, preferably greater than 1. 9. The use according to any of the preceding embodiments wherein said use as a biostimulant improves one or more of the following: a) nutrient use efficiency, b) tolerance to abiotic stress, c) quality characteristics, and d) availability of confined nutrients retained in soil or in the rhizosphere. 10. The use or method according to any one of the preceding embodiments, according to any of the preceding claims wherein the composition is essentially free of diallyl thiosulfinate. 11. The use or method according to any one of the preceding embodiments, according to any of the preceding claims wherein the composition is essentially free of diallyl disulfide. 12. The use, method or composition according to any of the preceding embodiments wherein the composition comprises at least 0.5 mg/L of a compound according to Formula I. 13. The use or method according to any of the preceding embodiments, wherein the plant belongs to the clade Embryophyta or to the clade Angiospermae. 14. The use or method according to any of the preceding embodiments, wherein the plant is selected from the group consisting of Phalaenopsis, Chrysanthenum, Solanum lycopersicum, and Lactuca sativa. 15. The use or method according to any of the preceding embodiments, wherein the composition further comprises a fertilizer, a pesticide, a wetting agent, an antimicrobial compound, disinfectant, chelating compound, aromatic compound, and/or an additional biostimulant. 16. The use or method according to any of the preceding embodiments, wherein said compound or composition is applied directly to said plant, to the seed of said plant, or to the soil of said plant or seed. 17. The use or method of embodiment 16, wherein said compound or composition is applied via drip irrigation. 18. A method comprising providing to a plant, preferably via irrigation, a composition comprising a compound according to Formula I: Formula I, wherein n is 2; wherein one X is -S- and the other X is selected from the group consisting of -S-, - S(O)-, and -S(O) _2- ; and R ¹ and R ² are independently selected from the group consisting of optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroalkyl, optionally substituted heteroaryl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, and optionally substituted heterocycloalkyl, preferably wherein the compound according to Formula I is di-n- propyl thiosulfonate (PTSO), di-n-propyl disulfide, di-methyl thiosulfonate, or di- phenyl thiosulfonate, wherein said composition is provided to the plant at least six times during the crop cycle of the plant and/or the composition is provided to the plant every 4-21 days during the crop cycle of said plant. 19. The use, method, or composition according to any one of the preceding embodiments, wherein said composition comprises an emulsifier. 20. The use, method, or composition according to any one of the preceding embodiments, wherein said composition comprises an amino acid based biostimulant. 21. The use, method, or composition according to any one of the preceding embodiments, wherein said composition comprises free amino acids and peptides. 22. The use of method according to any one of embodiments 1-19, wherein said use or method further comprises providing to said plant an amino acid based biostimulant. 23. The use of method according to embodiment 22, wherein the amino acid based biostimulant comprises between 8-15% (w/w) free amino acids and between 45-55% attached amino acids. 24. The use of method according to any one of embodiments 22-23, wherein the composition comprising a compound according to Formula I and the amino acid based biostimulant are provided within the same crop cycle. 25. The use of method according to any one of embodiments 22-24, wherein the composition comprising a compound according to Formula I is provided at least 24 hours prior or 24 hours after the amino acid based biostimulant is provided to said plant. DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENTS The disclosure provides organosulfur compounds for use as plant biostimulants as well methods to increasing the growth rate, development, yield, harvest of a plant, and other plant characteristics described herein. In some embodiments, the organosulfur compound is a compound according to Formula I: Formula I, wherein n is 2; wherein one X is -S- and the other X is selected from the group consisting of -S-, - S(O)-, and -S(O) _2- ; and R ¹ and R ² are independently selected from the group consisting of optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroalkyl, optionally substituted heteroaryl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, and optionally substituted heterocycloalkyl. In preferred embodiments, the compound according to Formula I is not In preferred embodiments, the compound according to Formula I is not The compounds according to Formula I are referred to herein as “organosulfurorganosulfur compounds” or ‘the biostimulant organosulfurorganosulfur compounds”. Preferably, R ¹ and R ² are independently selected from the group consisting of optionally substituted alkyl, and optionally substituted aryl. More preferably, R ¹ and R ² are independently selected from C _1-6 alkyl, and phenyl; wherein the phenyl group is optionally substituted with C _1-3 alkyl or C _1-3 alkoxy. Most preferably, R ¹ and R ² are independently selected from methyl, ethyl, n-propyl, n-butyl, phenyl, p- tolyl, and 4-methoxyphenyl. In preferred embodiments, R ¹ and R ² are identical. In preferred embodiments, each X is -S-. In preferred embodiments, one X is -S- and the other X is -S(O)-. In other preferred embodiments, one X is -S- and the other X is -S(O) _2- . Preferably, the compound of Formula I is selected from the compound according to Formula I is selected from the group consisting of di-n-propyl thiosulfonate (PTSO), S-methyl methanethiosulfonate, S-phenylbenzene thiosulphonate, di-n-propyl thiosulfinate (PTS), methyl methane thiosulfinate, butyl butane thiosulfinate, methyl propene thiosulfinate, di-n-propyldisulfide, dimethyl disulfide, diethyl disulfide, di-n-butyl disulfide, diphenyl disulfide, di-p-tolyl disulfide, and bis(4- methoxyphenyl) disulfide. More preferably, the compound according to Formula I is di-n-propyl thiosulfonate (PTSO), or di-n-propyl thiosulfinate (PTS). In preferred embodiments of formula I, n is 2 and one X is -S- and the other X is - S(O) _2- ; and R ¹ and R ² are independently selected from C _1-6 alkyl and phenyl, preferably selected from the group consisting of methyl, phenyl, and n-propyl. In preferred embodiments the compound of Formula I is propyl-propane thiosulfonate (PTSO), also referred to as di-n-propyl thiosulfonate. PTSO has the structure: In preferred embodiments, the compound of Formula I is propyl-propane- thiosulfinate (PTS), also referred to as di-n-propyl thiosulfinate. PTS has the structure: In preferred embodiments, the compound of Formula I is di-methyl thiosulfonate. In preferred embodiments, the compound of Formula I is di-phenyl thiosulfonate. PTSO and PTS are preferred compounds of the disclosure and may be used together or individually as biostimulants and in the methods described herein. As used herein, “alkyl” relates to a saturated aliphatic hydrocarbyl group. Unless stated otherwise, an alkyl group can be linear or branched. Preferably, alkyl groups are linear. As used herein, alkyl groups can be substituted or unsubstituted. Preferably, alkyl groups are unsubstituted. In preferred embodiments, in Formula I an alkyl is a C _1-6 alkyl, more preferably a C _1-4 alkyl. As used herein, “aryl” refers to an aromatic hydrocarbon ring system that comprises six to twenty-four carbon atoms, more preferably six to twelve carbon atoms, and may include monocyclic and polycyclic structures. When the aryl group is a polycyclic structure, it is preferably a bicyclic structure. Optionally, the aryl group is substituted by one or more substituents further specified in this document. Preferably, the aryl group is substituted with a methyl or methoxy group. Examples of aryl groups are phenyl and naphthyl. Most preferably, an aryl group is phenyl. As used herein, “alkenyl” relates to an unsaturated aliphatic hydrocarbyl group comprising one or more carbon-carbon double bonds. Unless stated otherwise, an alkenyl group can be linear or branched. Preferably, alkenyl groups are linear. As used herein, alkenyl groups can be substituted or unsubstituted. Preferably, alkenyl groups are unsubstituted. In preferred embodiments, in Formula I an alkenyl is a C _2-6 alkenyl, more preferably a C _1-4 alkenyl. As used herein, “alkynyl” relates to an unsaturated aliphatic hydrocarbyl group comprising one or more carbon-carbon triple bonds. Unless stated otherwise, an alkynyl group can be linear or branched. Preferably, alkynyl groups are linear. As used herein, alkynyl groups can be substituted or unsubstituted. Preferably, alkynyl groups are unsubstituted. In preferred embodiments, in Formula I an alkynyl is a C2-6 alkynyl, more preferably a C _1-4 alkynyl. As used herein, “cycloalkyl” refers to a cyclic saturated aliphatic hydrocarbyl group. Cycloalkyl groups can be substituted or unsubstituted. Preferably, cycloalkyl groups are unsubstituted. In preferred embodiments, in Formula I a cycloalkyl is a C _3-6 cycloalkyl, more preferably a C _3-5 cycloalkyl. As used herein, “heteroalkyl” relates to a saturated aliphatic hydrocarbyl group containing one or more heteroatoms. Unless stated otherwise, a heteroalkyl group can be linear or branched. Preferably, heteroalkyl groups are linear. As used herein, heteroalkyl groups can be substituted or unsubstituted. Preferably, heteroalkyl groups are unsubstituted. In preferred embodiments, in Formula I an heteroalkyl is a C _1-6 heteroalkyl, more preferably a C _1-4 heteroalkyl. Preferably, heteroalkyl groups contain one or more heteroatoms selected from the group consisting of O, N, and S, More preferably, heteroalkyl groups contain at most two heteroatoms, most preferably one heteroatom. Examples of suitable heteroalkyl groups include alkoxy groups (such as methoxy and ethoxy groups), and ethers. As used herein, “heterocycloalkyl” refers to a cyclic saturated aliphatic hydrocarbyl group containing one or more heteroatoms. Heterocycloalkyl groups can be substituted or unsubstituted. Preferably, heterocycloalkyl groups are unsubstituted. In preferred embodiments, in Formula I a heterocycloalkyl is a C _1-5 heterocycloalkyl, more preferably a C _1-4 heterocycloalkyl. Preferably, a heterocycloalkyl group is a 5-membered or 6-membered ring structure containing at most two heteroatoms, more preferably one heteroatom. Preferably, heterocycloalkyl groups contain heteroatoms selected from the group consisting of O, N, and S. As used herein, “heteroaryl” refers to an aromatic ring system comprising one or more heteroatoms. Preferably, heteroaryl groups comprise at least two carbon atoms (i.e. at least C ₂ ) and one or more heteroatoms N, O, or S. Preferably, heteroaryl groups contain at most five carbon atoms. Preferably, heteroaryl groups contain at most two heteroatoms selected from the group consisting of N, O, and S. In preferred embodiments, heteroaryl groups are 5-membered or 6-membered ring structures. Optionally, the heteroaryl group may be substituted by one or more substituents further specified in this document. Preferably, the heteroaryl groups are unsubstituted. Examples of suitable heteroaryl groups include pyridinyl, quinolinyl, pyrimidinyl, pyrazinyl, pyrazolyl, imidazolyl, thiazolyl, pyrrolyl, furanyl, triazolyl, benzofuranyl, indolyl, purinyl, benzoxazolyl, thienyl, phospholyl and oxazolyl. As used herein, “substituted” indicates that a group contains one or more substituents. Preferably, the substituents are independently selected from the group consisting of halogen, C _1-3 alkyl, -C(O)OH, -C(O)NH ₂ , -OH, =O, C _1-3 alkoxy, - NH ₂ , -NH-C _1-3 alkyl, -NHC(O)-C _1-3 alkyl, -NO ₂ , -SO ₃ H, and CF3. Preferably, halogens are selected from the group consisting of -Cl, -F, -Br, and -I. In preferred embodiments, the groups as disclosed herein contain at most three substituents, more preferably at most two substituents, and most preferably at most one substituent. A number of organosulfurorganosulfur compounds have been identified in extracts from plants belonging to the Allium family. Propyl- propane-thiosufinate (PTS) is a natural compound found in plants belonging to the Allium family; in particular Allium cepa (onion), Allium ampeloprasum (leek), Allium schoenoprasum (chive) and Allium chinense (Chinese onion). Propiin is hydrolysed by alliinase into propylsulfenic acid which condenses to produce PTS under loss of water (J. Chromatogr. A 1112 (2006) 3–22). Further reactions with PTS result in the production of PTSO. One of the best plant sources for PTS is from Allium schoenoprasum (chive) (see, table 3 of Rose et al. Nat. Prod. Rep., 2005, 22, 351–368). In contrast to PTS, PTSO is not present in onions. Although PTSO has been described in the literature as “Allium derived”, the inventors are not aware of any literature describing the measurement of PTSO from onion extract. Example 10 demonstrates that PTSO is not present at detectable limits in onion oil, onion extract, garlic oil, or garlic extract. Allium sativum (garlic) is reported to have non-detectable levels of PTS but significant amounts of allicin (i.e., diallyl thiosulfinate), which is not detectable in extracts of Allium cepa (onion), Allium ascalonicum (shallot), or Allium schoenoprasum (chive) (Rose et al.) Allicin is produced, upon raw garlic tissue damage from the non-proteinogenic amino acid alliin (S-allylcysteine sulfoxide) in a reaction that is catalyzed by the enzyme alliinase, as a major compound along with a small amount of methyl allyl thiosulfinate (Molecule, 19, 2014, 12591-12618 and J. Chromatogr. A 1112 (2006) 3–22). Allicin is unstable and quickly converts into a series of other sulfur-containing compounds such as diallyl disulfide. Since allicin is an unstable compound, its use in agriculture is limited (Fujisawa et al (2008) J Agric Food Chem: 56 (11): 4229-4235. The compounds can be either extracted from a natural source or can be produced synthetically. Both compounds PTS and PTSO are also commercially available. In some embodiments, the compounds are obtained from natural sources such as plants. Compounds can be extracted from plant material in various ways. The appropriate method depends on the chemical properties of the compounds. For example, the extraction can start with a non-polar solvent and follow that with solvents of increasing polarity. Alternatively, the compounds of the plant can be extracted in alcohol. The disclosure provides compositions comprising the biostimulant organosulfurorganosulfur compounds disclosed herein (i.e. according to Formula I). In some embodiments, the composition comprises at least 40%, preferably at least 50%, of one or more organosulfurorganosulfur compounds. Preferably, the composition comprises at least 40%, preferably at least 50%, of PTSO. In some embodiments, the composition further comprises PTS, preferably less than 20%, more preferably less than 10% PTS. Such compositions are also referred to herein as a “concentrated solution of organosulfurorganosulfur compound”. In some embodiments, at least 60 wt%, preferably at least 80 wt%, more preferably at least 95 wt%, of organosulfurorganosulfur compounds of the composition as disclosed herein are selected from compounds according to Formula I. In some embodiments, at least 60 wt%, preferably at least 80 wt%, more preferably at least 95 wt%, of organosulfurorganosulfur compounds of the composition as disclosed herein are selected from PTSO and PTS. The concentrated compositions will generally be diluted from between 1:100 to 1:100,000 before use to form working solutions. Herein, it will be understood that “working” indicates that the composition, e.g. a solution, can be applied to a plant, and not that other concentrations would relate to non-working embodiments. Suitable compositions comprise at least 0.5 mg/L of a organosulfurorganosulfur compound disclosed herein. Preferably, the composition comprises at least 0.5 mg/L, more preferably at least 1 mg/L of organosulfur compound (in particular PTSO) In some embodiments, a working solution comprises at least 10 mg/L of organosulfur compound (in particular at least 10 mg/L of PTSO). Preferably, the composition comprises at least 1 µmol/L, more preferably at least 10 µmol/L of organosulfur compound (in particular PTSO). In some embodiments, a working solution comprises at least 35 µmol/L of organosulfur compound (in particular at least 35 µmol/L of PTSO, more particularly at least 50 µmol/L of PTSO). Preferably, the composition, in particular when used as a working solution, comprises at most 10 mmol/L, more preferably at most 8 mmol/L of organosulfur compound (in particular PTSO). In some embodiments, a working solution comprises at most 6 mmol/L of organosulfur compound (in particular PTSO). In preferred embodiments a working solution comprises at most 3.5 mmol/L of PTSO, more preferably at most 1.5 mmol/L. In preferred embodiments, the compound according to Formula I is applied to plants (i.e., working solution) at a concentration of at most 200 mg /L, preferably at most 150 mg /L, more preferably at most 100 mg /L. In preferred embodiments, the composition that is applied to plants comprises at most 50 mg /L In some embodiments, the composition applied to plants comprises between 0.5-150 mg /L, preferably between 0.5-100 mg /L. In some embodiments, the composition applied to plants comprises between 0.5-50 mg/L. In some embodiments, the composition applied to plants comprises between 1-50 mg/L. In some embodiments, the composition applied to plants comprises between 1-10 mg/L. As a skilled person will recognize, the amount of PTSO needed will depend on the size of the crop, as larger crops generally need higher amounts. As an exemplary embodiment, an average plant density may be, e.g.30,000 plants/ha and 10,000 liters PTSO solution/ha is applied. In some embodiments, the compositions comprise additional organosulfur compounds, which may or may not also act as biostimulants. Preferably, at least 60 wt% of organosulfur compounds in said composition are selected from compounds according to Formula I. In some embodiments, when said composition comprises diallyl thiosulfinate, the ratio of the compound or compounds according to Formula I to diallyl thiosulfinate by weight is greater than 0.1 preferably greater than 1, and more preferably at least 10:1. It will be understood that when the composition comprises more than one compound of Formula I, the weight of all these compounds is compared to the weight of diallyl thiosulfinate to arrive at said ratio. In some embodiments, when said composition comprises diallyl disulfide, the ratio of the compound or compounds according to Formula I to diallyl disulfide by weight is greater than 0.1, preferably greater than 1, and more preferably at least 10:1. It will be understood that when the composition comprises more than one compound of Formula I, the weight of all these compounds is compared to the weight of diallyl disulfide to arrive at said ratio. Preferably, such compositions are substantially free of diallyl thiosulfinate. As used herein, “substantially free”, when referring to concentrated compositions having, for example, 50% or more of PTSO, refers to compositions comprising less than 5 wt%, preferably less than 1 wt%, more preferably less than 0.5 wt% diallyl thiosulfinate. Working solutions that have been diluted will comprise significantly less diallyl thiosulfinate. The compositions of the present disclosure are also preferably substantially free of diallyl disulfide. As used herein, “substantially free”, when referring to concentrated compositions having, for example, 50% or more of PTSO, refers to compositions comprising less than 5 wt%, preferably less than 1 wt%, more preferably less than 0.5 wt% diallyl disulfide. Working solutions that have been diluted will comprise significantly less diallyl disulfide. The compositions may include any suitable "agriculturally acceptable carrier, excipient, and/or solvent". Such carriers and solvents are known to a skilled person. and are not unacceptably damaging to a plant or its environment, and/or not unsafe to the user or others that may be exposed. For example, an agriculturally acceptable carrier may be a solid carrier, a gel carrier, a liquid carrier, a suspension, or an emulsion. A non-limiting example of a solvent is water. In preferred embodiments, the compositions further comprise an emulsifier. Suitable emulsifiers include propylene glycol and glyceryl polyethyleneglycol ricinoleate. Yuka extract as well as Tween are also suitable emulsifiers. In some embodiments, the compositions comprise 40-70% of an emulsifier, preferably between 55-60% emulsifier, in particular when the emulsifier is a combination of propylene glycol and glyceryl polyethyleneglycol ricinoleate. In some embodiments, the compositions comprise 70-92% of an emulsifier, preferably around 90% emulsifier, in particular when the emulsifier is yuka extract. In some embodiments, the compositions comprise 25-70% of an emulsifier, preferably between 25-35% emulsifier, in particular when the emulsifier is tween. Preferably, the composition comprises between 1-30%, preferably 3-10%, of a compound as disclosed herein (e.g., PTSO). The composition may further comprise vitamins and minerals such as vitamin H, vitamin B1, B2, B3, B5, B6, and B12. Such compositions can be diluted to a working solution to be applied on the plant as disclosed further herein. In some embodiments, the composition further comprises a fertilizer, a pesticide, a wetting agent, an antimicrobial compound, disinfectant, chelating compound, aromatic compound, and/or an additional biostimulant. A skilled person will also appreciate that a fertilizer, a pesticide, a wetting agent, an antimicrobial compound, disinfectant, chelating compound, aromatic compound, and/or an additional biostimulant (in particular an amino acid based biostimulant as described herein) may also be provided in a separate composition. For example, the disclosure further contemplates methods comprising providing to said plant a compound or composition of the invention as disclosed herein and providing to the plant one or more additional agents selected from fertilizer, a pesticide, a wetting agent, an antimicrobial compound, disinfectant, chelating compound, aromatic compound, and/or an additional biostimulant. Preferably, the additional agent is provided at around the same time as a compound of the invention. The additional agent may also be provided before or after a compound of the invention, for example several hours or days before or after a compound of the invention. Preferably the compound of the invention and the additional agent are provided within 7 days of each other. The additional agent is preferably provided multiple times during a crop cycle. For example, the additional agent may be applied every 4-14 days. The additional agent may be applied at least 4, preferably at least 6 times during a crop cycle. In particular, the composition comprising formula I and the additional agent are both provided during the same crop cycle. In some embodiments, the methods and uses disclosed herein further comprise applying an amino acid based biostimulant to a plant. An “amino acid based biostimulant” as referred to herein comprises at least 10%, preferably at least 15% (w/w) amino acids. In some embodiments, the biostimulant comprises at least 50%, preferably at least 55% (w/w) amino acids. The amino acids may be free amino acids (i.e., free form amino acids) or attached to other amino acids (e.g., via peptide bonds). In some embodiments, the amino acid biostimulant comprises between 8- 15% (w/w) free amino acids and between 45-55% attached amino acids. Such biostimulants are generally diluted 1:10 to 1:1,000 prior to use. Amino acid based biostimulants and their method of use are known to a skilled person and include Metalosate Calcium and Metalosate Fe (Albion Minerals, Layton, UT, USA); Agrocean B (Agrimer, Plouguerneau, France); Tecamin Brix, Tecamin Max, Tecnokel Amino Mix, and Terra-Sorb Foliar (Agritecno Fertilizantes, Valencia, Spain); Amino Quelant Ca (Bioibérica, Barcelona, Spain); Bosfoliar Activ (COMPO EXPERT, Münster, Germany); NaturalCrop SL (NaturalCrop Poland Sp. z o.o., Warszaw, Poland); and Delfan Plus (Tradecorp, Madrid, Spain). See table 2 of Molecules.2018 Feb; 23(2): 470 for a description of the composition of amino acid biostimulants AminoPrim and AminoHort, containing 15% and 20% amino acids, respectively, and 0.27% and 2.1% microelements, respectively. Terra Sorb ^TM Complex is another suitable amino acid based biostimulant comprising 20% (w/w) free amino acids; ASP, SER, GLU, GLY, HIS, ARG, THR, ALA, PRO, CIS, TYR, VAL, MET, LYS, ILE, LEU, PHE, and TRP. Terra Sorb Complex also contains 5.5% nitrogen of which 5% is organic N, as well as B (1.5%), Mg (0.8%), Fe (1%), Zn (0.1%), Mn (0.1%), Mo (0.001%), and 25% organic matter. A preferred amino acid based biostimulant is Isabion ^TM . Isabion ^TM is a mixture of water, ashes, free amino acids, as well as short-chain and long-chain peptides. Preferably, Isabion is a mixture of 33.5 % (w/w) of water, 4 % (w/w) of ashes and 62.50 % (w/w) of organic matter. In particular, the mixture comprises 10.3 % (w/w) free amino acids and 47.96 % (w/w) attached amino acids. Free amino acids include 3.80 % (w/w) of glycine, 1.45 % (w/w) of proline, 1.87 % (w/w) of alanine, 0.27 % (w/w) of glutamic acid, 0.85 % (w/w) of hydroxy-proline, 0.35 % (w/w) of aspartic acid, 0.20 % (w/w) of leucine, 0.35 % (w/w) of lysine, 0.09 % (w/w) of valine, 0.33 % (w/w) of tyrosine, 0.16 % (w/w) of phenylalanine, 0.07 % (w/w) of isoleucine, 0.12 % (w/w) of arginine, 0.08 % (w/w) of threonine, 0.08 % (w/w) of methionine, 0.10 % (w/w) of histidine and 0.13 % (w/w) of serine. Attached amino acids include 8.65 % (w/w) of glycine, 8.78 % (w/w) of proline, 5.16 % (w/w) of alanine, 6.33 % (w/w) of glutamic acid, 5.35 % (w/w) of hydroxy-proline, 2.71 % (w/w) of aspartic acid, 1.90 % (w/w) of leucine, 1.68 % (w/w) of lysine, 1.67 % (w/w) of valine, 1.14 % (w/w) of tyrosine, 1.18 % (w/w) of phenylalanine, 0.87 % (w/w) of isoleucine, 0.80 % (w/w) of arginine, 0.66 % (w/w) of threonine, 0.57 % (w/w) of methionine, 0.37 % (w/w) of histidine and 0.14 % (w/w) of serine. Further, attached amino acids can be short chain peptides and/or long chain peptides. The molecular weight of the short chain peptides is generally between approximately 1160 Da to approximately 3500 Da. The molecular weight of the long chain peptides is generally between approximately 3600 Da to approximately 8500 Da. Isabion is usually diluted with water and applied in a manner of foliar spraying or in irrigation water. When providing a working solution for foliar spraying, Isabion is normally diluted as 200-300ml/ 100 L water. The recommended dosage of Isabion is between 200 ml/hl to 300 ml/hl for foliar spraying and 2 l/ha to 3 l/ha for irrigation system. In case of frost or affected crops the dosage can be increased up to 400 ml/hl for foliar spraying and up to 4 l/ha for irrigation system.

In an exemplary embodiment, a method is provided comprising providing to said plant a compound according to Formula I, or a composition comprising a compound according to Formula I and providing to said plant an amino acid based biostimulant such as Isabion ^TM . In some embodiments, the compound according to Formula I and the amino acid based biostimulant are provided in a single composition. Accordingly, the disclosure provides compositions comprising a compound according to Formula I and an amino acid based biostimulant. In some embodiments, a composition comprises a compound according to Formula I, glycine, and proline. In some embodiments, a composition comprises a compound according to Formula I and free amino acids selected from the group comprising glycine and proline. Preferably, comprises a compound according to Formula I, free amino acids selected from the group comprising glycine and proline, and peptides. Preferably, the composition further comprises free amino acids selected from the group comprising alanine, glutamic acid, and hydroxy-proline; more preferably, the composition even further comprises free amino acids selected from the group comprising aspartic acid, leucine, lysine, valine, tyrosine, phenyl-alanine, isoleucine, arginine, threonine, methionine, histidine, and serine. In some embodiments a composition is provided, comprises a compound according to Formula I; alanine, glutamic acid, hydroxy-proline, aspartic acid, leucine, lysine, valine, tyrosine, phenyl-alanine, isoleucine, arginine, threonine, methionine, histidine, serine, glycine and proline as free amino acids; and peptides. In a preferred embodiment, the composition comprising Formula I as described herein and the amino acid based biostimulant as described herein are provided as separate compositions. Preferably, the composition comprising a compound according to Formula I is provided at least 24 hours prior (or between 1-3 days prior) or 24 hours after (or between 1-3 days after) the amino acid based biostimulant is provided to said plant. A kit of parts is also provided comprising i) a composition comprising Formula I as described herein and ii) an amino acid based biostimulant as described herein. In preferred embodiments, the composition comprising Formula I further comprises cadmium (Cd) in an amount of at most 1,5 mg/kg dry matter. In preferred embodiments, the composition comprises hexavalent chromium (Cr VI) in an amount of at most 2 mg/kg dry matter. In preferred embodiments, the composition comprises lead (Pb) in an amount of at most 120 mg/kg dry matter. In preferred embodiments, the composition comprises mercury (Hg) in an amount of at most 1 mg/kg dry matter. In preferred embodiments, the composition comprises nickel (Ni) in an amount of at most 50 mg/kg dry matter. In preferred embodiments, the composition comprises inorganic arsenic (As) in an amount of at most 40 mg/kg dry matter. In preferred embodiments, the composition comprises inorganic zinc (Zn) in an amount of at most 1500 mg/kg dry matter. di-methyl thiosulfonate, di-phenyl thiosulfonate The disclosure provides the organosulfur compounds and compositions comprising said compounds as disclosed herein, for use as plant biostimulants. Said compounds and compositions may be used in methods for treating plants. Such methods may be useful for increasing the growth rate and/or development of plants, increasing the yield of plants, or increasing the harvest of plants. In some embodiments, methods are provided comprising providing a plant with the compounds or compositions disclosed herein. A plant may be provided with said compounds or compositions by any means known in the art such as topical, watering feed, spray or damp solution, coating, piling, aerial solution, epidermal, intravascular via the roots, flowers, leaves and stalks. Preferred routes are uptake via the roots, spraying, aerial or topical administration. A preferred route of administration is via the roots using irrigation (e.g., drip/trickle irrigation). While not wishing to be bound by theory, providing the compounds directly to the roots may provide an improved effect over, e.g., spraying the leaves. Compare results between spray and drip irrigation in Table 17. Spraying the plants can also be effective, in particular when the composition is able to soak into the ground and reach the roots. In some embodiments, a compound of the invention is provided multiple times during a crop cycle. As used herein, a crop cycle refers to the time from germination until crop harvest. For example, the compound may be applied at least 4, preferably at least 6 times during a crop cycle. Preferably, the compound is applied every 4-27 days, in particular every 4-14 days. In an exemplary embodiment, the compound is provided every 1-2 weeks. In an exemplary embodiment the compound is provided every 4-27 days, preferably every 4-14, days and at least 4, preferably at least 6, times during a crop cycle. The first administration of said compound is preferably shortly after germination. Although the effect of the compounds lasts for several weeks after the last administration, it is recommended to apply the compound at least until 7 days prior to expected harvest. Said compounds or compositions may be applied to a plant (including cuttings, emerging seedlings, and established vegetation, including roots and above-ground portions, for example, leaves, stalks, flowers, fruits, branches, limbs, root, and the like), to the seed of a plant (e.g., prior to germination), or to the surrounding soil, in particular the plant rhizosphere. As used herein, the term rhizosphere refers to area of soil adjacent to the roots of living plants. The width of the rhizosphere is generally within 100 mm from the root surface. The compounds and compositions may be applied in a single administration or as multiple administrations. For example, the compositions may be provided daily, weekly, monthly or annually. In an exemplary embodiment the composition may be provided once daily for a week or until the biostimulant becomes effective. Watering the plants are performed as watering turns and the amount of supplied water is chosen such, that the plants discharge a part of the supplied water as drain. This means that organosulfur compositions rinse out relatively fast. To enable an even concentration in the root substrate, the organosulfur compositions may be dosed as a granulate that releases the composition at the desired rate. In this manner constant concentrations are provided over longer periods. In some embodiments, the compositions disclosed herein are provided as a spray solution. When the compositions are sprayed on the plants, the solution may be deposited on the leaves as droplets with a small surface volume ratio that evaporate, which may lead to the compositions remaining of the leaves as a residue. This effect can be reduced by including a wetting agent to the compositions. The amount of organosulfur compounds applied will depend upon a variety of factors including, the method of administration, the time of administration, the rate of decomposition of the particular compound being employed, the duration of the treatment, pesticide treatment, compounds and/or materials used in combination, the age, weight, general health and prior treatments, and like factors well known in the agricultural arts. A horticulturist, plant grower or a farmer having ordinary skill in the art can readily determine the effective amount of the composition required. It is clear to a skilled person that lower concentrations/amounts of the organosulfur compounds can be administered to slow growing plants, e.g. cactus and succulents. It is also clear to a skilled person that the concentrations/amounts in water and frequency of application are dependent on the plant species, subspecies, cultivar, hybrid, variant. Furthermore, it is clear to a skilled person in the art that the dosage that the plants can tolerate, is dependent on the growth stage and size of the plant. Furthermore, it is clear to a skilled person in the art that the concentrations/amounts in water and frequency of application are dependent on the growth conditions e.g. light, temperature, evaporation, nutrient concentration and pH in the root substrate, air movement and the application of other pesticides. Furthermore, it is clear to a skilled person in the art that the concentrations/amounts in water and frequency of application is dependent on the moment that it is administered, day, night and the season and weather conditions. In an exemplary embodiment, the organosulfur compound, preferably PTSO, is provided in an amount of from 0.01 kg/ha to 100 kg/ha. Preferably, for use on orchids, preferably Phalaenopsis, the organosulfur compound, preferably PTSO, is provided in an amount of from 10 kg/ha to 100 kg/ha, more preferably from 20 kg/ha to 60 kg/ha. Preferably, for use on Chrysanthemum the organosulfur compound, preferably PTSO, is provided in an amount of from 0.01 kg/ha to 1 kg/ha, more preferably from 0.01 kg/ha to 0.25 kg/ha. In some embodiments, the compound of Formula I, or a composition comprising said compound, is applied directly to said plant, to the seed of said plant, or to the soil of said plant or seed. As demonstrated in the examples, the compounds disclosed herein have advantageous effects on plants, in particular on the quality characteristics of plants. Said compounds are therefore useful as plant/soil additives, fertilizers, and biostimulants. In a preferred embodiment, the term “biostimulant” as used herein refers to a product, in particular a compound or composition, that stimulates the nutritional processes of a plant independently of the nutrient content of the product with the aim of improving one or more of the following properties of the plant or the plant rhizosphere: a) nutrient use efficiency, b) tolerance to abiotic stress, c) quality traits (also known as quality characteristics), and d) availability of confined nutrients in soil or rhizosphere. In a preferred embodiment, the use of a compound as described herein as a biostimulant, relates to improving one or more of the following: a) nutrient use efficiency, b) tolerance to abiotic stress, c) quality traits, and d) availability of confined nutrients retained in soil or in the rhizosphere. In preferred embodiments, the use as a biostimulant does not encompass the use as an antimicrobial and/or antifungal agent. Preferably, the organosulfur compounds disclosed herein: - increase nutrient use efficiency and/or - increase tolerance of a plant to abiotic stress and/or - improve the quality characteristics of a plant and/or - increase the availability of nutrients retained in soil or in the rhizosphere for a plant. More preferably, the organosulfur compounds disclosed herein: - - increase nutrient use efficiency and/or - - increase tolerance of a plant to abiotic stress and/or - - improve the quality characteristics of a plant. Nutrient use efficiency As used herein, nutrient use efficiency is used in its normal definition in the art. Typically, nutrient use efficiency is defined as yield (biomass) per unit input (fertilizer, nutrient content) (see, e.g., Nutrient Use Efficiency in Plants, Concepts and Approaches, Editors: Hawkesford, Malcolm J., Kopriva, Stanislav, De Kok, Luit J. (Eds.) ISBN 978-3-319-10635-9). Preferably, the nutrient is nitrogen (N) and/or phosphorus (P). The skilled person is well aware of methods to determine the nutrient use efficiency of a plant, and therefore is also fully capable of establishing whether a biostimulant increases said nutrient use efficiency. For example, in field studies nutrient use efficiencies can be either calculated based on differences in crop yield and/or nutrient uptake between plots treated with a biostimulant and an untreated control, or by using isotope-labeled nutrients to estimate crop and soil recovery of applied nutrients (see for example A. Dobermann, Nutrient use efficiency – measurement and management, in: Fertilizer Best Management Practices, 2007, ISBN: 2-9523139-2-X). Abiotic stress As used herein, abiotic stress is defined as the negative impact of non-living factors on living organisms in a specific environment. As such, an improvement of tolerance of a plant to abiotic stress indicates that the plant is better capable to tolerate abiotic stress factors that typically have a negative impact on the plant, e.g. reduction of plant growth rate. Abiotic stress factors include, but are not limited to, drought, excess of water (in particular, too much rain or too high a humidity), too much or too little direct sunlight, strong wind, suboptimal soil structure, salinity (in particular hypersalinity), too low or too high temperatures, strong and/or sudden fluctuations in temperature, and other environmental extremes. By contrast, plant pathogens or insect pests are referred to as biotic stresses. The negative impact on the plant resulting from abiotic stress includes, but is not limited to, slower growth rate of the plant, lower maximum height of the plant, decreased root formation, improper leaf development (such as smaller leaves, leaves having a different colour), higher susceptibility to insect damage or pathogen damage, and fewer flowers or flower stalks. An average improvement of the tolerance to abiotic stress of a plant as the result of treating a plant with a biostimulant can be measured by comparing plots with plants treated with a biostimulant with an untreated control, wherein the treated plants and control plants are subjected to substantially the same abiotic stress factors, e.g. when the treated plants and control plants are grown on the same or neighboring plots. In a preferred embodiment the abiotic stress is drought, excess of water, direct sunlight, heat, and/or coldness, that results in slower growth, decreased root formation, pale or red leaves, higher susceptibility to insect or pathogen damage, and/or fewer flowers or flower stalks, in a plant of the genus Phalaenopsis. In a preferred embodiment, the abiotic stress relates to the uptake of too little nutrients or too little water because of the lack of sufficient roots, too high temperatures, and/or air movement that results into poor and slow root formation in a plant of the genus Chrysanthemum. Quality traits The definition of quality traits (also known as quality characteristics) may depend on the plant genus or species. Typically, the skilled person, e.g. a farmer or a grower, knows which plant relates to which quality trait. Some examples of crops/ornamental plants and some of their quality characteristics are described below. Other quality traits are described at table 31.

The term "improvement in plant quality" refers to the qualitative or quantitative improvement of certain traits when compared with the same trait in a control plant which has been grown under the same conditions in the absence of the application of the compounds disclosed herein. Such traits include, but are not limited to, improved visual appearance of the plant, improved quality of harvested material, e.g. seeds, fruits, leaves, vegetables; including visual improvement of harvested material, improved nutritional content, enhanced shelf-life, etc. In some embodiments, the plant quality is plant vigor. Improved plant vigor includes, e.g., improved plant vitality of the plant; improved plant stand; improved emergence; and/or more developed root system; enhanced nodulation; larger leaf blade; improved leaf color, increased plant size; increased plant weight; increased plant height; increased yield when grown on poor soils or unfavorable climate; earlier flowering/fruiting/germination/grain maturity; faster and more uniform ripening; and the like. In some embodiments, the plant quality is plant yield and refers to the yield of a plant (e.g., grains, nuts, fruits, vegetables, seeds, etc). Improved plant yield includes, e.g., an increase in biomass production and an improved ability to harvest plant matter. In some embodiments, improved quality characteristics refers to one or more of the following characteristics selected from improved visual appearance of the plant, improved quality of harvested material, improved nutritional content, enhanced shelf-life, improved plant vigor, and improved plant yield. Availability of confined nutrients retained in soil or in the rhizosphere As the skilled person is aware, part of the nutrients may be confined in the soil or in the rhizosphere, rendering some amount of nutrients unavailable to the plant. Confined nutrients include, but are not limited to, nutrients with low mobility in the soil or rhizosphere, and/or nutrients that are poorly soluble in water. Low mobility may for example be the result of the nutrient interacting with other soil components, such as clay-sized particles or mineral-associated organic matter. The physicochemical interactions between the nutrient and the other soil component may result in limited availability of the nutrient to the plant (Jilling et al. Biogeochemistry (2018) 139: p.103–122). Various methods to measure the availability of confined nutrients in soil and the rhizosphere are available (see, for example, Brinkley and Vitousek, Soil nutrient availability, in: Plant Physiological Ecology: Field Methods and Instrumentation (ed. by Pearcy, Ehleringer, Mooney, and Rundel), 2000, ISBN: 13:978-0-412-40730- 7). Furthermore, methods are provided for: - increasing the growth rate and/or development of plants, - increasing the yield of plants, - increasing the harvest of plants. As is understood by the skilled person, an increase in, e.g., in the growth rate of a plant refers to the increase of growth rate of a planted treated with a compound disclosed herein as compared to the growth rate of a plant grown under similar conditions without treatment. As used herein, the term "plant" encompasses crop plants, ornamentals, trees, grasses, annuals, perennials or any other commonly cultivated member of the kingdom Plantae. The term "crop plant" as used herein includes plant species with commercial value, which are planted and cultivated for commercial use. Thus, crop plants include floral and non-floral plants, perennials and annuals, trees, shrubs, vegetable plants, fruit trees, turf, and ground cover. Suitable plants include Cymbidium, Oncidium, Miltonia, Paphiopedilum, Cypripedium, Calanthe and the orchid genus hybrids, Bromelia, Begonia, Impatiens, Azalea, ferns; the horticultural crops sweet pepper, tomato, egg-plant, cucumber, zucchini, etc; the arable crops: wheat, potato, beet, chore, Luzerne etc; arable horticulture crops, endive, cauliflower, Brussels sprouts, lettuce, broccoli, chicory, peas, beans, red cabbage, kale, etc; the garden plants Azalea, magnolia, forsythia, peony, hollyhock, laburnum, palm, wisteria, etc; fruit trees and bush: apple tree, pear tree, cherry tree, prune tree, gooseberry, black currant, blueberry, cranberry, etc; tropical fruits: banana, papaya, cassava, pineapple, avocado, mango, etc. Preferably the plant belongs to the clade Embryophyta. Preferably, the plant is a vascular plant. In exemplary embodiments the plant is a crop plant such as Lactuca sativa (lettuce). In other preferred embodiments, the plant belongs to the clade Angiospermae. Preferably, the plant belongs to a family selected from the group consisting of nightshades (Solanaceae), cucumber (Cucurbitaceae), roses (Rosaceae), orchids (Orchidaceae), lily (Liliaceae), composite (Asteraceae or Compositae), carnation (Caryophyllaceae), crucifers (Brassicaceae or Cruciferae), grass (Poaceae), and umbellifers (Apiaceae or Umbelliferae). In a preferred embodiment, the plant belongs to the nightshades family (Solanaceae). Preferably, the plant belongs to the genus Solanum or Capsicum. Preferably, the plant belongs to the genus Solanum and is selected from the group consisting of tomato (S. lycopersicum), potato (S. tuberosum), eggplant (S. melongena), and pepino (S. muricatum). In other preferred embodiments, the plant belongs to the genus Capsicum and belongs to the species pepper (C. annuum), in particular sweet pepper, chili pepper, and jalapeño. In a preferred embodiment, the plant belongs to the cucumber family (Cucurbitaceae). Preferably, the plant belongs to the genus Cucumis or Cucurbita. Preferably, the plant belongs to the genus Cucumis and is selected from the group consisting of cucumber (C. sativus), sugar melon, and gherkin (C. anguria). In other preferred embodiments, the plant belongs to the genus Cucurbita and is selected from the group consisting of C. pepo (in particular zucchini), and pumpkins (C. argyrosperma, C. digitate, C. maxima, and C. moschata). In a preferred embodiment, the plant belongs to the rose family (Rosaceae). Preferably, the plants belong to a genus selected from the group consisting of strawberries (Fragaria), pears (Pyrus), apples (Malus), roses (Rosa), and Rubus (in particular of the subgenus Rubus, viz. blackberries). In a preferred embodiment, the plant belongs to the orchid family (Orchidaceae). In exemplary embodiments, the plant is an ornamental plant such as an orchid, in particular of the Phalaenopsis genus, or another flowering plant such as from the genus Cymbidium. In a preferred embodiment, the plant belongs to the lily family (Liliaceae). Preferably, the plant belongs to the genus of tulips (Tulipa) or lilies (Lillium). In a preferred embodiment, the plant belongs to the composite family (Asteraceae or Compositae). Preferably, the plant belongs to the genus of Chrysanthemum, Asterea, or Lactuca. In a preferred embodiment, the plant belongs to the carnation family (Caryophyllaceae). In a preferred embodiment, the plant belongs to the crucifers family (Brassicaceae or Cruciferae). Preferably, the plant belongs to the genus Brassica. In a preferred embodiment, the plant belongs to the grass family (Poaceae). Preferably, the plant belongs to the genus of Triticum, Oryza, or Zea. In a preferred embodiment, the plant belongs to the umbellifers family (Apiaceae or Umbelliferae). Preferably, the plant is selected from the group consisting of carrots (Caucus carota), parsnip (Pastinaca sativa), anise (Pimpinella anisum), coriander (Coriandrum sativum), cumin (Cuminum cyminum). In some embodiments, the plant is not cumin. Preferably the plant is selected from the group consisting of Phalaenopsis, Cymbidium, Chrysanthenum, Rosa, Fabaceae (preferably Phaseolus, more preferably Phaseolus vulgaris), Brassica (preferably Brassica oleracea and Brassica rapa), Cucurbita (preferably Cucurbita pepo giromontiina, Cucumus melo, and Cucumus sativus), Solanaceae (preferably Solanum or Capsicum, more preferably Solanum lycopersicum or Capsicum annuum), Vitis (preferably Vitis vinifera), Vaccinia (preferably Vaccinia corymbosum or Vacciniumcyanococcusi), and Lactuca (preferably Lactuca sativa). As used herein, "to comprise" and its conjugations is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. In addition the verb “to consist” may be replaced by “to consist essentially of” meaning that a compound or adjunct compound as defined herein may comprise additional component(s) than the ones specifically identified, said additional component(s) not altering the unique characteristic of the invention. The articles “a” and “an” are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, “an element” means one element or more than one element. The word “approximately” or “about” when used in association with a numerical value (approximately 10, about 10) preferably means that the value may be the given value of 10 more or less 1% of the value. The invention is further explained in the following examples. These examples do not limit the scope of the invention, but merely serve to clarify the invention. EXAMPLES The present experiments demonstrate for the first time the effect of PTSO/PTS as a biostimulant. Despite that the growth conditions (watering, fertilization, light, temperature, air movement, air humidity) were optimal for the ornamental pot plant Phalaenopsis hybrid “Pure silk”, the administration of various amounts of PTSO/PTS resulted in higher growth rates and improved plant characteristics, as is demonstrated in example 2. In periods of high temperatures and much light in the greenhouse, the treated plants continued growing at high rates, whereas growth of untreated plants slowed down. Apparently, the PTSO treated plants were better capable of resisting periods of increased abiotic stress. Example 3 shows that treating Chrysanthemum cuttings with various amounts of PTSO/PTS resulted in increased growth and better root development. In this experimental design, treated cuttings were compared to untreated cutting under the same conditions for optimal rooting and pregrowth of the cuttings. In this example, treatment with PTSO/PTS demonstrated increased root formation and growth of the cuttings compared to untreated cuttings under optimal conditions. Moreover, these experiments also showed an additional effect of a more efficient nutrient uptake. This indicates that the PTSO/PTS compositions used herein are biostimulants. Example 1 Isolation of PTSO and PTS. Scope: For a number of examples described herein, an aqueous extract of PTSO was used, referred to herein as PTSO EXTRACT (PE), comprising at least 56% PTSO wt % and up to 14% PTS wt %. Study design: the order of elution of compounds according to their polarity is estimated from high-performance liquid chromatography (HPLC). The conditions for separation are determined by thin-layer chromatography (TLC) using heptane and ethyl acetate as the mobile phase. A flash column with a length of 110 cm and a diameter of 25 cm was packed with 15 kg silica (particle size 40-60 µm from ACROS Organics™) in heptane and the column was allowed to stabilise overnight. Purification was carried out by increasing the polarity gradually from 0% to 40%. The fractions of interest, PTS (= peak 6) and PTSO (= peak 7), both identified by proton nuclear magnetic resonance ( ¹ H-NMR), started to elute after 20 litres use of mobile phase and were collected in 2 litres fraction size. The fractions were separated according to the TLC identification of each compound and the corresponding fractions for each compound (PTS or PTSO) were combined. The solvent was evaporated by rotary evaporation to obtain a purified fraction of PTS (32435-2-A) and two purified fractions of PTSO (MHA32435-2-B, MHA32435-2-C) as outlined in table 1. The required purity of >98% was only achieved with the fraction MHA32435-2-B (= PTSO) while the fraction MHA32435-2-A (PTS) and MHA32435-2-C (= 2 ^nd fraction of PTSO) showed a purity < 98% and needed further purification individually by a second flash chromatography to obtain the desired purity. The repurification of PTS (MHA32435-2-A) was carried out by packing a flash column (50 cm length and 20 cm diameter) with 2 kg silica (particle size 40-60 µm from ACROS Organics™), using ethyl acetate and heptane as the mobile phase and by increasing the polarity from 0% to 20%. The fractions of interest were collected in 250ml fraction size, identified by TLC and combined. The solvent was evaporated by rotary evaporation to obtain PTS (EWR32514-01-1) with >98% purity. The repurification of the impure fraction of PTSO (MHA32435-2-B) was done at the same flash column, using the same mobile phase as for MHA32435-2-A with the difference of 3kg silica (for packing the column), increasing the polarity from 0% to 30%, and the fraction size was 100 ml. The repurification resulted in two fractions (EWR32514-02-1 and EWR32514-02-02) of PTSO with a purity >98% as outlined in table 1.

From this example it is demonstrated that PTSO and PTS were purified up to high purity. For examples 2-5 described below, PTSO EXTRACT (PE) contains 56% PTSO and around 30% glyceryl polyethyleneglycol ricinoleate. Example 2. Treatment of ornamental plants Scope: in this example the biostimulant effect of PTSO EXTRACT was demonstrated. For this purpose, the orchid Phalaenopsis “Pure silk” was selected. Growth and development of plants encompasses three stages: (1) vegetative growth, (2) flower induction, and (3) development of flower stalks. After the treatments as mentioned below, the plants were evaluated at the end of the flower induction period. At the time of sale flowering of the plants were evaluated. Plant cultivation procedure Plants of Phalaenopsis “pure silk” (Floricultura B.V.) were produced from meristems and pregrown. Upon delivery at the Phalaenopsis grower the plants were processed according to the following procedure. The plants were potted up in a transparent 12 cm pot in middle-sized bark (Supplier: Bas van Buuren B.V., De Lier), cultivated for 30 weeks at 29°C, and showered every 5 days with water plus fertiliser (100 litres per m ² ) (EC 1.1). If needed, the plants were exposed to artificial light (from 7:00 a.m. until 6:00 p.m.). For flower induction, the plants were cooled down and cultivated for two months at 19°C. Hereafter, the plants were kept for 3-4 months at 20 – 25°C, and were optionally exposed to artificial light if needed. In this way, flowering plants were obtained that had the appropriate size in line with market demands. In July 2020 young Phalaenopsis plants were potted up in bark. July was a hot and sunny month, and despite that the grower was using shadowing screens, the plants showed hanging, thin leaves that had a dark green/reddish colour, with little growth progress. This indicated that the plants suffered from abiotic stress. The number of roots and root growth, was monitored by visual inspection through the transparent pots. Considerable variations in number of roots and root growth were observed within the plant population. The following experimental design was set up with the objective to determine the sensibility of the plants for various dilutions and number of treatments by PTSO EXTRACT. Areas of 1 m ² (containing about 100 plants) were treated with dilutions of PTSO/PTS containing extract and were manually showered by dilutions in water (10 L/m ² ), as follows. Manual watering with the diluted PTSO EXTRACT took place directly after the regular 5 day’s showers. In this way, the water content of the root substrates of the control and treated plants were about the same. Treatment 1: 2x treated with 1,000x dilution of PTSO EXTRACT in a feed solution (EC 1.1), supplied every other watering (interval was 10 days); Treatment 2: 2x treated with 2,500x dilution of PTSO EXTRACT in a feed solution (EC 1.1), supplied every other watering (interval was 10 days); Treatment 3: 8x treated with 1,000x dilution of PTSO EXTRACT in a feed solution (EC 1.1), supplied every other watering (interval was 10 days); Treatment 4: 8x treated with 2,500x dilution of PTSO EXTRACT in a feed solution (EC 1.1), supplied every other watering (interval was 10 days); After the treatments, the treated plants undergo the same cultivation procedure as the control plants, i.e. the untreated plants. After 36 weeks the plants were scored on the features as follows. Differences between plants were expressed in terms of amount of roots, interrupted root growth, progressive leaf development, number and length of leaves, plant and bark quality (assessed by colour and water retention, i.e. estimated weight). Evaluation went as follows: from the Control plants, the largest and the smallest plant were selected. The largest was rated 5, and the smallest 1. The same scoring procedure was followed with regard to the rating of root formation: the plant with the most roots is rated 5, and the one with the fewest roots is rated 1. The length of the largest fully developed leaf was measured with a tape measure. “6-7” leaves means that 6 leaves were already fully developed, and a seventh leaf was still growing. “Leaf thickness” was scored by the resistance of the leaf when it was bowed by hand. “Bark quality” was scored by judging the degree of composition that has taken place. The wetter and muddier the bark was, the lower the score was. “Progressive growth” is an estimate of the extent to which a plant's leaves are larger than the previous leaf. In particular, the last fully developed leaf was compared with the penultimate leaf developed. “Plant size was scored as follows: the bigger the plant, the higher the score. For “Plant characteristics” the main focus was on the size of the plant. The control plants were rated from 1 to 5, and compared to treated plants. If any one of the treated plants had developed better with regard to an assessment criterion, they can score above 5. The plants with the worst “Plant characteristics” was rated “1”, and the plants with the best characteristics was rated 5. Results and discussion The averages of the measurements are summarised in Table 2, and are based on the raw data. The data were collected 36 weeks after the treatments: the plants had just left the refrigerated part of the greenhouse for two weeks for flower induction.

The plants that are treated twice with the 1,000x and 2,500x dilutions of PTSO EXTRACT showed significantly less root growth than the control. Despite that the roots of these treated plants were less developed than those of the control plants, the roots of the treated plants enable the plant to grow faster. Similar, but more pronounced observations were done for the plants that were treated 8 times with both dilutions: the size of the plants were largest of all treatments. Additionally, the roots showed a considerably better root development. Furthermore, there were not only more roots, but the roots had larger growth tops and were thicker. It was concluded that the largest effect on the Phalaenopsis plant was the treatment with the 1,000x dilution that was applied 8 times. As is shown in table 1, the quality of the root substrate bark was also scored. Bark slowly decomposes by microbial activity during the cultivation of plants. When the bark is decomposed, it changes into a wet anaerobic substance that could result in die off of roots. While Table 1 shows a slightly lower rating of bark quality for the treated plants (2.72-3) as compared to the control plants (3.18), these differences are so small that no adverse effects were expected for the treated plants. Conclusions A very pronounced effect of PTSO EXTRACT on the scored plant properties was demonstrated. Growth stimulation was observed compared to the control plants. Since no plant growth hormones were present in the PTSO EXTRACT, this composition falls under the category of Biostimulants. During the test period it was clear that the plants were not capable of growing at the maximal growth rate during the experiments that resulted in abiotic stress (there were periods of drought, heat and very much light). In the experiments it was shown that PTSO EXTRACT is capable to compensate for the abiotic stress. The fertilising conditions were exactly the same for all plants, yet more plant biomass was formed together with improved plant characteristics in the plants treated with PTSO EXTRACT. This indicates that the nutrient use efficiency was higher for the plants treated with PTSO EXTRACT. Another interesting observation was that the plants had a very clear shine on the leaves. This was attributed to the formation of a thicker layer of wax on the leaf and is considered as an indication of better plant health. Without wishing to be bound by theory, it is believed that a thick layer of wax typically decreases water evaporation from the upper leaf surface, which contributed to the decrease in abiotic stress. The observations made after the treatments on Phalaenopsis in which PTSO EXTRACT was applied two times, have shown that this was sufficient to induce a long term effect over a cultivation time of more than 6 months, which was very surprising. Flowering of the plants was unaffected by the treatments and the plants represented an excellent commercial product. No deviations have been observed in terms of wilting, abnormal flowers, stalk shape or size. In this example it is clearly shown that the PTSO EXTRACT is a powerful biostimulant. Example 2b. Treatment of Phalaenopsis plants Scope: in this example the biostimulant effect of PTSO EXTRACT was demonstrated on survival after repotting and flower stalk production during the cultivation trajectory. For this purpose, various Phalaenopsis hybrids were selected. Growth and development of plants encompasses three stages: (1) vegetative growth, (2) flower induction, and (3) development of flower stalks. The same grow-up regime was followed as described in example 2. After the treatments as mentioned below, the plants were evaluated at failure after repotting and the number of flower stalks at the end of the cultivation cycle. Scope: during grow up of Phalaenopsis, the grower is regularly confronted with significant loses after transplanting. This may count up to 10% dependent on the size, condition and genetic background of the hybrid. In this example it was demonstrated that PTSO EXTRACT strongly decreases the failure of (young) Phalaenopsis plants after transplanting and increases the number of flower stalks prior to sale of the plants. For this purpose, various hybrids of Phalaenopsis were grown from meristems and pregrown in 70 hole trays until a diameter of 5 cm with Floricultura. Hereafter the plants were delivered at the grower and were transplanted from 70 hole trays to 45 hole trays with pea/cocos plugs as a substrate (Xcellent Plug Quick plug B.V., Monster, The Netherlands). Repotting of a plant is considered as a stressful period. It is inevitable that roots are damaged and directly after repotting the root substrate (bark) often has not the optimal properties in terms of moisturising and capillarity. The plants experience this as drought, a kind of abiotic stress. After repotting, the plants were treated with 2500x diluted PTSO EXTRACT weekly (800 ml/ha). After 26 weeks after repotting 13,000 plants were checked on failure (= complete die-off) and compared to 13,000 untreated plants. The results are presented in table 2a. Table 2a. Failure of some Phalaenopsis hybrids of untreated and treated plants. Failure means: completely die off. From these results it is clear that treatment with PTSO-Extract has a strong positive effect on survival after a repotting that may be considered as a stressful handling. After 26 weeks, the plants were potted up in transparent 12 cm pots and cultivated in the same cultivation regime as is indicated in example 2. The hybrids Mekong, Orinoco, Ferrara and Goya were evaluated on gowth as indicated in Example 2, and with all these hybrids growth stimulation was observed (raw data are not shown here). After flower stalk induction in a refrigerated room the number of flower stalks are counted per plant. For that purpose 800 plants were evaluated per hybrid (see table 2b). Table 2b. Average number of flower stalks of treated and untreated plants of various Phalaenopsis hybrids after bloom induction.

Example 3. Treatment of Chrysanthemum cuttings PTSO EXTRACT was tested on biostimulant activity as is defined in Regulation 2019/1009 of the EU. The results were checked for the occurrence of the 4 mentioned properties on rooting and growth of Chrysanthemum cuttings. The experiments were performed by an independent research institution Vertify. The Netherlands. Scope: in this example the effect of PTSO EXTRACT was demonstrated as a biostimulant. For this purpose, cuttings of the Chrysanthemum variety “Chic” were selected. Chrysanthemum cuttings were planted in fertilised standard potting soil in a flat plant container (a “plot”. Each plot consisted of 30 plants). With all treatments, three repeated treatments were done on the roots as indicated below with a 1-week interval. Temperature, light control and relative humidity in the greenhouse compartment were recorded with a climate computer (Sercom). After the treatments the plants were evaluated at the end of the flower induction period. The last assessment was performed 13 days after the last treatment. The cuttings were judged on root formation, length of the stalks, and overall condition of the plant. Plant cultivation procedure Rooted Chrysanthemum “Chic” cuttings with the same length were delivered by Royal van Zanten, the Netherlands. The trial was done under controlled conditions in greenhouse facilities. Crates of 40x60 cm and 10 cm depth were filled with a fertilised standard potting soil (organic medium) in which the Chrysanthemum cuttings were planted. Each plot consisted of 2 crates with 15 plants each (30 plants per plot). The treatments (a specific dilution) existed of three applications with intervals of 1 week, the first application was done at 1 week before transplant (rooting phase), a second application was done at transplant. A final application was done 1 week after transplant. Randomisation of the treatments takes place in the test greenhouse, and where the plants are positioned is determined using Genstat software. Statistical analysis of trial results is done with the same software. Details are given in de result section of this example. Temperature and relative humidity in the greenhouse compartment were recorded with the climate computer and were set at 23 °C and 50% respectively. Applications targeting roots were done as drench or spray. The first application on roots was done by drenching the plants in the solutions during approx. 15 minutes. The untreated plots were drenched in water. The cuttings were kept in crates with their roots in a layer of water until transplanting them into crates with soil. Further applications were done by spraying the solutions on the soil, followed by a gentle rain to incorporate the products in the rooting zone. The application and assessment details are summarized in Table 3. The treatments are summarized in Table 4. Previcur Energy is a fungicide, and Trianum-P is a biological fungicide.

At each assessment date, the height of 10 centre plants per plot were measured. Additional assessments on general crop vigor were done. General crop vigor was recorded in 1-10 index scale (1=very poor crop vigor; 10=excellent (above normal) crop vigor) and is based on the impression of the general health. At the last assessment date, fresh weight of the above ground plant mass was measured. Rooting density at the bottom side of the crates was recorded. For this purpose, the crates were turned over and the percentage of roots that covers the underside of the bottom were estimated. Statistical analysis was done with Genstat (LSD test at 95%). In the table P means probability. When P has a value of 0.05 or less, the difference between two treatments is statistically significant. The least significant difference (lsd) is the smallest difference between significant different treatments at 95% (P = 0.05). Values indicated with the same letter do not significantly differ (P = 0.05). 1 litre PTSO EXTRACT was dissolved into 1,000 litres of water (dilution rate 1:1,000) and this volume of 1,001 litres was sprayed onto the soil with a surface of 1 ha). Results Results after analysis of the crop height are summarized in Table 5.

Table 5. Development of the crop height with the various treatments as a function of time. The columns with the crop height indicate the statistic groups after LSD statistical analysis. With PTSO EXTRACTat the highest concentration (1:1000), at transplant 0 DA-B, plants were significantly shorter compared to all other treatments. At a concentration of 1:2,500, no adverse effect of the drench treatment on crop height was found. After repeated applications and during the trial period, the differences remained visible. A dose response was constructed with PTSO EXTRACT. The tallest plants were measured at concentrations 1:10,000 and 1:50,000. General crop vigor was recorded in 1-10 index scale (1=very poor crop vigor; 10=excellent (above normal) crop vigor). Crop vigor is a subjective measurement on plant color and shape. Results are summarized in Table 6.

On general crop vigor, only PTSO EXTRACT at a concentration of 1:1,000 performed less compared to all other treatments. At the last assessment date (19 days after transplant), fresh weight of the above ground plant mass was measured. Rooting density at the bottom side of the crates was recorded. Results are summarized in Table 7.

The fresh weight of the above ground plant mass of plants treated with PTSO EXTRACT at 1:1,000 concentration, applied as soil treatment, was less compared to the other treatments. Although rooting at transplant seemed to be affected, the final results obtained 19 days after transplant, showed no adverse effects on rooting. With this treatment the rooting density was even higher compared to the other treatments. After all soil treatments with PTSO EXTRACT, the rooting density was equal (entry 7 in Table 7) or even higher (entries 4-6, and 8 in Table 7) as compared to the untreated plots and also both references Previcur Energy and Trianum-P. After the first application during the rooting phase (drench) with PTSO EXTRACT at the highest concentration (1:1,000), hardly any roots were noted. The plants were also shorter compared to the untreated plots. Also at a concentration of 1:2,500 of PTSO EXTRACT fewer roots were observed compared to the untreated and reference plants Previcur Energy and Trianum-P. After repeated applications and during the trial period, after soil applications a dose-response relationship was observed for treatments with PTSO EXTRACT. The tallest plants were measured at the lower concentrations of PTSO EXTRACT, viz. 1:10,000 and 1:50,000. At these concentrations, the plants were significantly taller compared to the untreated plants until 2 weeks after planting. When subjected to the highest concentration of PTSO EXTRACT, viz.1:1,000, plants were smaller compared to all other treatments. The differences were also reflected by fresh weight at the last assessment date (19 days after transplant). Although during treatments with PTSO EXTRACT at 1:1,000 concentration, rooting during the rooting phase (drench) was affected, and plants were smaller compared to those subjected to other treatments, no adverse effects on final rooting were found. After treatment with PTSO EXTRACT at 1:1,000 concentration, rooting at 19 days after transplant was numerally even better compared to the other treatments. with the other tested concentrations. Furthermore, PTSO EXTRACT when applied as soil treatment resulted in numerally better rooting compared to the untreated plots and also both references Previcur Energy and Trianum-P. Chrysanthenum is a cut flower that is produced in large quantities and it is retailed by weight. In this example it is clearly demonstrated that said compositions result in more weight and is therefore beneficial for the horticulturist. From these experiments it is also clear that the right dosages of this biostimulant must be dosed in order to obtain the biostimulating effects. Example 4. Treatment of lettuce seeds and seedlings Seeds of the lettuce (Lactuca sativa) variety “volare” were obtained from Enza Zaden, and Trianum P from Bayer AG, Crop Science Division. Seeding boxes (45 with 30 cm, 8 cm depth, 9 litres of soil/seeding box) were filled with standard seeding soil (BVB Substrates) that consisted of fine organic medium in which lettuce was seeded. The obtained seeding soil was fertilized by the producer, no additional fertilisation was performed during the experiment. Each plot consisted of 1 seeding box with 50 seeds and planted at a depth of 2 cm. The seeds were treated close before seeding as indicated in table 8. The solutions with PTSO EXTRACT were prepared with tap water. Applications were done by drenching the seeds in the prepared solutions for 10 minutes. After drenching the seeds were dried to the air dried and seeded. The untreated seeds were drenched in water. “Vigor seed” was used as a reference agent. The boxes were covered with a lid until germination. Temperature was set at 21 °C, an air humidity varied between 70 – 95%. Light exposure was realised by three 25 Watt LED-tubes at 30 cm distance from the plants (50 µmol). After germination the lid was removed. Randomisation of the treatments was done manually. Statistical analysis of trial results is done with Genstat software. Temperature, light control and relative humidity in the climate were controlled and recorded with a climate computer (Sercom). Trial details are summarized in table 9. When all seeds had fully germinated, the plants were scored as normal, small or abnormal (plants with malformed cotyledons or leaves), general crop vigor was recorded in 1-10 index scale. At the last assessment date (4 weeks after planting the seeds,) fresh weight of the above ground plant mass was measured. At each assessment date the numbers of germinated plants were counted per plot. After full germination, the plants were scored as normal, small or abnormal (plants with malformed cotyledons or leaves). Additionally, general crop vigor was recorded in 1-10 index scale (1=very poor crop vigor; 10=excellent (above normal) crop vigor). At the last assessment date, fresh weight of the above ground plant mass were measured. Statistical analysis was done with Genstat (LSD test at 95%). In the table P means probability. When P has a value of 0.05 or less, the difference between two treatments is statistically significant. The least significant difference (lsd) is the smallest difference between significant different treatments at 95% (P = 0.05). Figures with the same letter do not significantly differ (P = 0.05).For example, in the treatments at 12 DA-S, no statistically significant difference was observed between untreated plants (“a”) and Vigor Seed (“a”), PE; 1:50,000 (“a”), or PE; 1:25,000 (“ab”); but statistically significant differences were observed between untreated plants (“a”) and PE; 1:10,000 (“bc”) and PE; 1:5,000 (“c”). Similarly, the PE; 1:5,000 (“c”) treatment different significantly from all other treatments except PE; 1:10,000 (“bc”). Results and discussion At each assessment date the numbers of germinated plants were counted per plot. When all plants had fully germinated, the plants were scored into the categories normal, small or abnormal (abnormal plants have malformed cotyledons or leaves). Results are summarized in tables 10 and 11.

Only some minor differences were found between numbers of germinated plants and numbers of normal plants, indicating that only few small or abnormal plants were found. During germination and at full germination, no significant differences were found between treatments on both numbers of germinated and numbers of normal plants. The germination level with all treatments was very good. The treatments did not affected germination or quality of the seedlings either positive or negative. At 12 days after seeding and later assessment dates, fall out of plants was found, specifically in the untreated, vigor seed and lower PE concentrations. No explanation was found: plant pathogens or other plaques were not detected. Significant differences were found between the treatments. A dose response was constructed with PE. With PE at the highest concentration (1:5,000), no fall out of plants was found. At the lowest concentration (1:50,000), PE was comparable to the untreated plots. With the lower dilutions of PE (i.e. PE at the higher concentrations), when applied as drench application on seeds, the seedlings were more resilient compared to seedlings from untreated seeds. Significant effects were measured at concentrations 1:5,000 and 1:10,000. With Vigor Seed, no effects were observed with the untreated plots. General crop vigor was recorded in 1-10 index scale (1=very poor; 10=excellent (above normal). Crop vigor is an estimation on plants, in this case color and shape (table 12).

At 1:5,000 and 1:10,000 dilution rate resulted in some better vigorous plants compared to lower concentration, Vigor Seed and the untreated plots. At the last assessment date (28 days after seeding; 24 days after germination), fresh weight of the above ground plant mass was measured. The results are summarized in table 13. All treatments with PTSO EXTRACT dilutions lead to an increase in fresh weight over control. Conclusive, the germination level with all treatments was very good. The treatments had not negatively affected germination or initial quality of the seedlings. Seedlings germinating from seeds treated with PE 1:5,000 and 1:10,000 were significantly more resilient compared to seedlings from untreated seeds and Vigor Seed. Less fall out of plants (± 1% versus ± 10% untreated) was found, while also crop vigor was better compared to untreated plots. Also the weight of the crop measured 28 days after seeding was more when treated with PE 1:5,000 and 1:10,000 and resulting in 11% more crop weight versus untreated and 26% more than benchmark Vigor Seed. The plant size was 4 – 6 full-grown leaves on that moment. With the reference agent Vigor Seed, no effects were measured compared to the untreated plots. Conclusion The present example demonstrates that the use of PTSO EXTRACT leads to larger heads of lettuce and greater yield per input of nutrients (i.e., a marker of nutrient utilization efficiency), as well as increased crop vigor, providing further evidence of the biostimulant effect of the compounds disclosed herein. Example 5. Treatment of tomato plants Scope: in this example the biostimulant effect and the manner of administration of PTSO EXTRACT (PE) was demonstrated. For this purpose, the commercial tomato production race “Xandor” was selected. Plant cultivation procedure The tomato race “Xandor”, from Axia seeds, The Netherlands was used. The tomato plants were pregrown at a size of 60 cm. Tomato plants of the race “Xandor” were precultivated and the plants were placed on rock wool mats (Grodan (ROCKWOOL B.V.) in a greenhouse in spring. The plants were fed and on-line adjusted dependent on the actual evaporation and weather by a computer system delivered by Priva B.V. All the nutrients in the plant feed were supplied in excess and the composition was sampled weekly and checked on nutrient limitations. The EC value was maintained between 2.3 – 3.0 and the pH was kept at 5.4 and continuously corrected. In table 14 the growth parameters are presented that were adjusted, monitored and controlled. Table 14 indicates the settings, but the actual values vary considerably because of the variable changes in weather conditions during the day.

The treatments are summarized in Table 16. Serenade is a fungicide that is often applied in tomato crops. Table 16. Treatment list. Each treatment consists of a group of 13 plants. The applied spray volumes were 150 ml/m2 each time, in case of administering on the mat 100 ml/plant was dosed. Additional assessments on general crop vigor were done. General crop vigor was recorded in 1-10 index scale (1=very poor crop vigor; 10=excellent (above normal) crop vigor) and is based on the impression of the general health. Crop vigor criteria were “the general condition of the plants (freshness of the plant, firmness of the leaves, healthy leaves)” “tomato head quality” (diameter of the head, thickness of the stalk and were rated from 1 (very poor) to 10 (excellent) and colour of the leaves (rated from 1 (yellow) – 5 green). Furthermore, once per week the ripe tomatoes were harvested and measured. Statistical analysis was done with Genstat (LSD test at 95%). In the table P means probability. When P has a value of 0.05 or less, the difference between two treatments is statistically significant. The least significant difference (lsd) is the smallest difference between significant different treatments at 95% (P = 0.05). Values indicated with the same letter do not significantly differ (P = 0.05). After planting on the mats crop development took place as was expected for this race. On Day 124 the assessments were started. The results are presented in tables 17-20. Table 17 demonstrates that the PTSO-EXTRACT does not have a negative effect on cumulative tomato production and at a dilution of 1:10,000 slightly increased cumulative tomato production. A number of plant quality parameter were scored, including tomato head quality (Table 18), plant health condition (Table 19) and crop colour (Table 20). All dilutions of the PTSO-EXTRACT showed improved quality with respect to tomato heads, plant condition and plant colour. The fertilising conditions were the same for all plants, yet more plant biomass was formed together with improved plant characteristics in the plants treated with PTSO EXTRACT. This indicates that the nutrient use efficiency was higher for the plants treated with PTSO EXTRACT. The observations made after the treatments on tomato plants in which PTSO EXTRACT was applied in the first 4 weeks of tomato crop cultivation, have shown that this was sufficient to induce a positive effect over the cultivation time of more than 6 months, which was very surprising. No deviations have been observed in terms of wilting, flower bud and/or flower fall, abnormal fruit, stalk or leaf shape or size. Despite that all the treatments showed an improvement of crop quality parameters, it was found that only one administration method was effective in increasing the harvest, namely repeated treatments by dripping with a 25,000 x diluted PTSO EXTRACT: this resulted in a cumulative tomato production increase of 8% In this example it is clearly shown that the PTSO EXTRACT is a powerful biostimulant, in particular when it is administered more than once by the irrigation water . 0 1777 11.50 11.39 11.47 11.26 11.09 11.38 12.49 11.4 xample 5b. Treatment of various tomato races. this example the biostimulant effect of PTSO EXTRACT (PE) was demonstrated various tomato races and with different growers. ope: tomato plants of various races were cultivated with different growers and re treated with PTSO Extract. In table 20a the tomato races and growers are mmarised. The same tomato cultivation regime was used as described in ample 5. ble 20a. Applied tomato races, treatment data and the percentage cumulative ld increase compared to untreated tomato plants of the same race grown under e same conditions at the end of cultivation. nclusion: treatment with PTSO Extract clearly shows a yield increase with all ted tomato races and is broadly applicable. xample 6 Lettuce sed on the results from above, an agricultural composition was prepared mprising 5.2% PTSO. The composition further comprises 59% emulsifier opylene glycol and glyceryl polyethyleneglycol ricinoleate). The composition is erred to herein as “PTSO Composition 5.2”. orchard of open field lettuce variety Iceberg was selected. A randomised mplete block design was done, with 4 replications per treatment. Six drip plications were conducted through drip irrigation system, with 120 kPa of essure and 10000 l/ha of water volume. eatment 1: UNTREATED CHECK + FARMER ROGRAM + MATTER ORGANIC 10 L/ha eatment 2: 0.5 l/ha PTSO Composition 5.2 + FARMER PROGRAM + MATTER RGANIC 10 L/ha. eatment 3: 1 l/ha PTSO Composition 5.2 + FARMER PROGRAM + MATTERRGANIC 10 L/ha the examples described herein, “FARMER PROGRAM” refers to the standardowing conditions used by the farmers, such as for example, nutrients, standardop protection, light regime, etc. eatment e treatments were applied six times approximately every two weeks with ervals from 14-24 days. The last treatment is referred to as treatment “F” and DA-F referred to blow refers to the assessment carried out 10 days after the al treatment (treatment “F”). e marketable yield (the number of lettuces per hectare, the kilograms of lettucesr hectare (kg/ha), weight per lettuce in grams and the percentage of marketable tuces in the harvest) was assessed at 10 DA-F. In addition, the number of non-arketable lettuces per hectare and the percentage of non-marketable tuces in the harvest, was carried out at 10 DA-F. hen treatment 1 is give the value 100%, the rest of the treatments showed higher lues for marketable yield. Treatment 3 showed the highest value (102% on the mber fruit per hectare, 121% on the kilograms per hectare, 118% on averageams per fruit and 102% on percentage of marketable lettuces in the harvest), lowed treatment 2 (101% on the number fruit per hectare, 110% on the ograms per hectare, 108% on average grams per fruit and 102% onrcentage of marketable lettuces in the harvest). hen treatment 1 is give the value 100%, the rest of the treatments showed lower lues for unmarketable yield. Treatment 3 showed the lowest value (61% on the mber fruit per hectare and on percentage of unmarketable lettuces in the rvest) followed by treatment 2 (69% on the number fruit per hectare and onrcentage of unmarketable lettuces in the harvest). boratory tests were conducted on 8 lettuces per plot with similar developmentage, one assessment was carried out at 10 DA-F, evaluating the aerial fresh ight (g), the root weight (g), the lettuce firmness (kg/cm2) and the fruit diameterm). garding the fresh weight of the aerial part and the fresh weight of the root, when atment 1 is give the value 100%, the rest of the treatments showed higher lues. The highest fresh weight of the aerial part and the root was obtained by atment 3 (117% and 123%, respectively), followed by Treatment 2 (107% and 1%, respectively). garding the lettuce diameter, when treatment 1 is give the value 100%, atment 3 had a value of 107% and treatment 2 a value of 104%. garding the lettuce firmness, when treatment 1 is give the value 100%, atment 3 had a value of 133% and treatment 2 a value of 125%. nally, 5 lettuces per plot with a similar stage of development were taken m each harvest and weighed, placed in a cold room at 6ºC and the weight loss r lettuce was evaluated over the following days; 92 DAP (Days After Plant), 93 DAP, 94 DAP, 95 DAP, 96 DAP, 97 DAP, 98AP, 99 DAP, 100 DAP, 101 DAP, 102 DAP, 103 DAP and 104 DAP, calculatinge percentage of weight lost per lettuce over the whole period of conservation. en, the same lettuces were left at room temperature (14ºC) and the weight loss r lettuce was re-evaluated in the following 7 days; 105 DAP, 106 DAP, 107 DAP, 8 DAP, 1109 DAP, 110 DA and 111 DAP, calculating at the end the percentage of ight lost per lettuce in the whole period. xample 7 Cucumber orchard of cucumber variety Katrina was selected. Elemental plots were 182, with 13 plants per plot. Fourteen drip applications (applicationsBCDEFGHIJKLMN) for PTSO Composition 5.2 and seven applications CEGIKM) for Isabion ^TM , were conducted using a drip irrigation system, with 000 l/ha of water volume and with 120 kPa of pressure. The applications re carried out with an interval of 7 days for PTSO Composition 5.2 and 14 ys for Isabion ^TM. eatment 1: UNTREATED CHECK eatment 2: Farmer check eatment 3:0.4 l/ha PTSO Composition 5.2 + Isabion 4L/ha + 41g free amino ds, 40g nitrogen, 118 g organic carbon eatment 4: 0.4 l/ha PTSO Composition 5.2 e marketable yield (the kilograms of fruits per hectare (kg/ha), the number ofuits per hectare and fruit weight (g), was assessed at 3 DA-B (i.e., 3 days after atment B), 6 DA-B, 3 DA-C, 6 DA-C, 3 DA-D, 6 DA-D, 3 DA-E, 7 DA-E, 4 DA-F, DA-G, 5 DA-G, 3 DA-H, 6 DA-H, 3 DA-I, 7 DA-I, 5 DA-J, 3 DA-K, 7 DA- 4 DA-L, 1 DA-M, 5 DA-M and 3 DA-N calculating at the end, the total yield d average. The diameter and length of fruit (mm) was assessment at 3 DA-E and DA-K. garding the marketable yield (kg of fruits per hectare and number of fruits per ctare), when treatment 1 is give the value 100%, treatment 3 obtained theghest yield (116% on kg/ha and 113% on number of fruits), followed by treatment 112% on kg/ha and 110% on number of fruits) and treatment 2 (104% on kg/ha d 104% on number of fruits). garding the diameter of fruit, when treatment 1 is give the value 100%, atment 3 resulted in 103-104%, treatment 4 resulted in 102-104% and treatment n 102-103%. garding the length of fruit, when treatment 1 is give the value 100%, treatment esulted in 106-107%, treatment 4 resulted in 106% and treatment 1 in 103- 5%. xample 8 Treatment of cloned Cymbidium plants tflower producing Cymbidium growers usually have to grow their own plantsfore flower production can take place. In order to obtain flowers that are as iform as possible, they have to pregrow their plants from clones (meristems): itay take 5 years or more before the production of flowers is on the economically sired level. owth and development of plants encompasses three stages: (1) vegetative growth ring which a pseudobulbs are formed at the end of shoot formation, (2) flowerduction, and (3) development of flower stalks. It is economically interesting to ep the grow-up time as short as possible to grow up the plants to flowering e.In this experimental design a PTSO extract (at least 56% emulsified SO(PE)) is used to demonstrate the biostimulatory effect of PTSO on young mbidiums plants. r this purpose, young meristem plants of the orchid Cymbidium “49er” were ected. The plants had still to develop the first pseudobulb after transplanting m the flask. After the treatments as mentioned below, the plants were evaluated indicated below after 206 days. perimental Design ant cultivation procedure ants of Cymbidium “49er” were produced from meristems. Upon delivery at the mbidium grower, the plants were potted into black 9 cm pots in middle-sizedco peat to which Osmocote fertilisation granules were added (1,25 kg/, M ³ ). Theants were fed twice a day with 40 ml fertilised feed (EC 0.4) via an automatic tering system via an infusion system. The plants adapted to the green housenditions and the treatment with PTSO EXTRACT began approximately 4 months er re-potting. the example, 25 plants were used per treatment. The distance between the ants were about 15 cm. The plants were monitored on growth of leaves by easuring the length and largest wideness of the largest leaf, on pseudobulb mation, final size and appearance and number of new shoots. The number of ots and green root tips were monitored by visual inspection. Furthermore, an erall judgment was done on the plants with respect to appearance and althiness. Per treatment, 8 to 24 plants were judged. e dilutions of PTSO extract, the frequency and intervening time between curring treatments is indicated in table 21. The plants were manually ministered with 40 ml of the indicated dilution PTSO extract. The control was tered with 40 ml the standard fertilised plant feed as indicated above. After the atments, the treated plants undergo the same cultivation procedure as the ntrol plants, i.e. the untreated plants. e plants were scored on the indicated variables at t=0, t=112 days and t=206 ys. e height and thickness of the pseudobulb, the length and wideness were easured by the use of a tape-line. The quantity of roots and the fresh white owing root tips were estimated on a scale of 1 – 10. e quantity of roots were judged after comparison of the roots of a plant with a ant with an average root formation of the control group. For this purpose, the ants were taken out of the pot and compared to a standard plant that is judged as verage” of the control treatment. e number of fresh root tips were judged as follows. 1: 0 – 20% of the roots showedhite growing root tips; 2: 20 – 40% of the roots showed white, growing root tips; 3: – 60% of the roots showed fresh growing root tips; 4, 60 – 80% of the roots hadowing, white root tips; 5: 80 – 100% of the roots showed growing white root tips. e “Appearance of new shoots” is calculated as the number of new shoots dived bye total number of judged plants of the treatment. e “Robustness” of the plants was an arbitrary judgment that was given after aant was compared to an average plant of the control group and varied from 1 – : 1 is the lowest score and a 10 is the highest score. sults the tables 22 - 24 the results are presented of the averages of the treatments.

8 9 10 11 12.6 11.9 11.6 12.0 0 0 1 0.75 0 0 0.44 0.44 dev dev dev dev 19.0 19.9 19.0 19.8 0.13 0 0.13 0.13 3 3 3 3 3 3 3 3 4.8 4.1 4.4 4.1 1 7 3 5 8 9 10 119/2.8 10.4/1.5 9.6/2.6 9.1/2.74 3.8 4.6 5.01 2.8 3.1 3.5 9.9 17.6 22.9 19.9 19 19.88 1.5 2.6 2.79 4.2 4.3 5.9 3 4 41 5.0 5.2 6.3 6 5 1 8 9 10 11 8.9/ 10.4/4.7 9.6/ 9.1/ 6.2 5.2 5.8 5.4 3.8 4.6 5.6 3.1 2.8 3.1 3.6 36.0 28.8 37.9 42.3 25.3 24.5 26.5 24.1 1.2 1.00 1.1 1.1 5 5 5 5 5 5 5 5 4.6 5.0 4.8 6.2 5 2 3 1 re detected by the PTSO-extract. A ranking was made for the plants at t=0 (Table 2), t strictly speaking, the differences between the plants were extremely small. This is ual for plants that are grown from meristems and cultivated under the samenditions for 4 months prior to the start of the experiment. Hereafter the plants were ated according to the schedule as is presented in Table 21. ter 112 days the plants of treatment 11 were significantly larger and more robust able 23.). A well-developed robust plant with a high score is a plant with relative large eudobulbs (for the storage of reserve carbohydrates), large leaf-surface (for otosynthesis, a fast-growing large new shoot and a well-developed root system for the take of water and minerals. Repeated dosing of PTSO EXTRACT resulted in more sitive effects (see, e.g., treatments 7-11). xample 9 Effect of organosulfur compounds on lettuce and sweet peppers perimental design. The bio-stimulatory effects of organosulfur compounds was tested lettuce and sweet pepper (Capsicum annuum “Ritmico”). The tested compoundsclude di-n-propyl disulfide (CAS 629-19-6), di-n-propyl thiosulfonate (i.e., PTSO, CAS 13-13-9), di-methyl thiosulfonate (CAS 2949-92-0), and di-phenyl thiosulfonate (Cas 12-08-4). Di-methyl thiosulfonate and di-phenyl thiosulfonate were ordered from rich-Sigma. PTSO was purified as described in example 1. In order to obtain a stable d homogenous emulsion, the compounds were dissolved into an emulsifier solution ble 25) to assure that the crops are supplied with the defined solution. In this way it is evented that precipitations or immiscibility occurred of the organosulfur compounds. examples herein, “PTSO Composition 5.2” refers to an agricultural compositionmprising 5.2% PTSO and further comprises 59% emulsifier (propylene glycol andyceryl polyethyleneglycol ricinoleate). “PTSO composition 5.2 Yuka” in an agriculturalmposition comprising 5.2% PTSO and 90.2% Yuka extract. “PTSO composition 5.2ween” in an agricultural composition comprising 5.2% PTSO, 30.1% Tween, .1%DMSO and 30% water. The controls and treatments are indicated in table 27. e dosage of the test compounds was standardized on base of the molar dosage and the me molar dosage was administered as PTSO. Emulsions were prepared by adding thequired amount of the compounds as indicated in table 25 in 100 ml volumes of 50% een 80 and 50 ml DMSO. Hereafter, the volumes were supplemented to a final volume 250 ml with the same mixture and incubation took place at an orbital shaker at 37 °C0 minutes, 250 rpm).

fore seeding, the seeds of lettuce were drenched into 1000x diluted emulsions as dicated in table 25 and incubated for 10 minutes. Each treatment was performed in 4- d. In table 26 the growth settings of lettuce and sweet peppers are summarized and in ble 27 a summary of the realized growth conditions and crop harvest is presented of tuce. demonstrated at Table 27, all treatments of lettuce showed an increase in relative sh weight/plant compared to control and increased harvest weight per plant mpared to control. At the time of measuring the growth of peppers, no fruits were yet esent. However, preliminary results indicate that all treatments led to an increase in op vigor as measured by the relative size compared to control.

xample 10 Analysis of PTSO in Onion and Garlic oil ope: onion and garlic oil and onion and garlic extracts were obtained as described Hemat S. Abd El-Salam et al. (2014)( I Enhancement of Cumin (Cuminumminum L.) Productivity Using Some Natural Plant Extracts. Egypt. J. Hort. Vol. , No. 2, p 209-219. The samples were analysed for the presence of PTSO as lows. perimental design: The presence of PTSO (di-n-propyl thiosulfonate) was tected by LC-MS/MS. Standards of PTSO (CAS 1113-13-9) were obtained byganic synthesis from Symeres (Mercachem Holding B.V.). The identity of thempound was confirmed by ¹ H-NMR and LC-MS and the purity was determined LC-UV and was determined to be > 99.1%. is sample was used to prepare equilibration graphs. For spiking anduilibration, samples were prepared containing pure PTSO from 2 to 200 µM inPLC-grade methanol. e LC-MS/MS (API4000, Sciex) had the following configuration: synchronizationode setting is LC-Sync, as pre-column the Vanguard BEH C182.1 x 5 mm and asPLC column the Acquity BEH C182.1 x 50 mm 1.7 µm were used. The injector s supplied by Nexera. e oven was set at 40°C. The pumping mode was ternary flow. The pump settings re the following: total flow was 0.4 ml/min; pump B concentration (%) is 0.0, mp C concentration (%) is 50.0. The pump B and pump C curves were 0, the nimum pressure and maximum pressure limits were 0 and 16,000 psi,spectively. Pump A was used for solution LC-A (0.05% FA (Formic Acid) in 5%ethanol in UPW (Ultrapure water)). Pump C was used to pump methanol. ethod: calibration standards in the range from 2.00 to 200 µM (PTSO) were shly prepared in MeOH. olation of PTSO from the samples was performed by extraction into organic vent (methanol (MeOH), ethyl acetate (EtOAc), n-butanol and dichloromethane CM)). The ratio between sample and extraction solution is maximal 1 or smaller. eparative research showed that the extraction efficiency of the sample is between and 40% and therefore, reference samples must be included in the procedure. mple volumes of 20µl were injected by the autosampler. e extracts were analyzed using an API 4000 LC-MS/MS system (PTSO). ta acquisition was performed using Analyst software (version 1.6.3) from AB iex. Following peak area integration, regression was also performed using alyst. Concentrations were calculated using weighted linear regression, cording to the following formula: y = a + bx (weighting factor = 1/x2) where: x = SO concentration in µM y = Peak-area ratio a = Intercept b = Slope. e calibration range for PTSO is 2.0 – 200 µM, the quantitative assay range > 2,0 M, the qualitative assay range is > 1.0 µM, both with a sample volume of 20 µl. om these results it is demonstrated that no PTSO was detectable in onion and rlic derived from the respective oils and extracts. xample 11 Effects on other crops ope: The effects of the PTSO extract were tested on various other crops. The bles describe the results from crops where a visible effect in at least one easured variable was observed. udy design: Table 32 summarizes the crops tested with the corresponding growthnditions and treatments. The crops were precultivated with plant growers andanted in plastic greenhouses with constant aeration (day and night) or in theen fields. The plants were fed via plugs or irrigation water. All the nutrients ine plant feed were supplied in excess. Dependent on the crops, fruits were rvested at regular time intervals and the cumulative weight of the fruits wastermined. The PTSO Extract was supplied via the roots via the plant feed. With imited number of crops, root formation and chlorophyll content were alsoeasured. table 32 the growth variables that were monitored and the harvests areesented. The growth parameters temperature, relative humidity and lightpply vary considerably because these parameters were not controlled andpendent of the weather conditions that change during the day. Weathernditions are changing with the seasons and so the month that the experiments re started is indicated in the table. In June the light intensity is highest and the riability of the day-night temperature, the corresponding relative humidity andaporation are largest. These (extreme) variabilities result in high abiotic stress.nce it is assumed that PTSO Extract reduces the sensibility of the plants for iotic stress, it was expected that the larger the changes of the abiotic stress tors is, the more pronounced the positive effects of the treatment are on theops. ble 33 demonstrates that PTSO Extract did not show any negative effects onop properties like damaged leaves, crop colour, deformed leaves or size, stalks,uit shape and flowers and did not affect root formation negatively. Crop condition s unchanged or better. e growth conditions were kept the same for PTSO Extract -treated and treated plants (controls). This implies that the nutrient use efficiency was higher PTSO Extract-treated plants and this makes PTSO a biostimulant. nce the greenhouse aeration was constant during the day and not controlled as anction of temperature, high temperature and humidity deviations are expectedpendent on the wind and sun. The relative air humidity varies inverselyoportional with temperature, so large deviations are also expected. Irrigation ter supply may also become limiting during hot periods and this results in the take of too little water uptake and loose of cell-turgor, resulting in hangingaves and closing of the stomata. On that moment photosynthesis stops. These controlled environmental factors result in a lot of abiotic stress, and while not shing to be bound by theory, it is suggested that PTSO Extract diminishes the ect of abiotic stress on plants, resulting in a higher level of photosynthesis- ated metabolites, healthier crops and higher crop yields. Dependent on the crop, ditional positive properties were observed, as an improved root system and a gher level of chlorophyll (table 33). Significant faster growth and improved crop operties were obtained with other crops (rose, thicker and/or longer stalks and iny leaves; melons, greener and bigger leaves; string beans, a significant larger op; tomatoes, a larger head and more chlorophyll). ble 31 provides a summary of improved crop characteristics after treatment with SO Extract. Not all possible crop characteristics were monitored, so other aracteristics were likely also improved but were not measured in the present periment. 1