FIELD

[0001] The present disclosure relates generally to compositions for protecting plants from pathogens; and more specifically, to use of compositions comprising rosin, at least one solvent and at least one auxiliary agent for treatment of crop plants, particularly for antifungal treatment of crop plants. Furthermore, the present disclosure also relates to methods of treating plants using the aforementioned compositions.

BACKGROUND

[0002] Generally, many species of plants around the world have developed different ways of protecting themselves from herbivores. For example, some plants develop thorns on their leaves or stems to prevent herbivores from eating them while others secrete poison capable of incapacitating or fatally wounding the herbivores that try to consume them. Furthermore, while some trees may not possess an ability to defend themselves from injury caused by herbivores, the trees secrete resin to protect themselves from further injury and/or to repair damage caused by such an injury. However, in-spite of all these defence mechanisms, plants are still incapable of defending themselves from pathogens and microbes.

[0003] For centuries, farmers have used various techniques to defend crops from attack by pathogens and/or microbes. One such technique is associated with use of lime and wood ash to eliminate parasites that could potentially lay waste to entire crop-fields. Also, pesticides derived from petrochemical products such as crude oil, sulphur and bitumen are conventionally well-known to protect plants. Furthermore, metal-based pesticides employing copper, lead and/or mercury have been used as common pesticides and biocides. Usually, such pesticides are sprayed over the crop-fields to prevent the growth of pathogens and/or microbes on the crops.

[0004] Although widely used, chemical pesticides and biocides (such as, pesticides and biocides employing petrochemical products, metal-based pesticides and biocides, and so forth) are associated with major drawbacks. Firstly, chemical pesticides are toxic to both organisms that they are intended for such as the pathogens and/or microbes, and also to other organisms such as cattle, stray animals, pets and even humans. Secondly, certain chemical pesticides are often effective for only a short period on particular organisms. In such instances, the organisms become immune to the chemical pesticides after prolonged exposure thereto and consequently, the chemical pesticides may no longer be effective in preventing growth and harm to the crops by the organisms. Thirdly, accumulation of the chemical pesticides may lead to bio-magnification, wherein chemical residues of the chemical pesticides left behind in the crops or plants, makes them unfit for human or animal consumption. Furthermore, the chemical pesticides may soak into soil in the crop-fields and/or underground water used for irrigation in the crop-fields, thereby contaminating the soil and/or underground water with the chemical residues. It will be appreciated that when such contaminated soil is exposed to animals and/or humans, the contaminated water is used to spray the crops, or used for animal or human consumption, the animals and/or humans may be at great risk of experiencing severe damage.

[0005] As traditional plant protection products (pesticides) are potentially toxic, in most countries their use is regulated, i.e. pesticides must be approved for sale and use by a government agency. For example, within the European Union the active substance of the pesticide needs first to be approved for the EU, followed by the approval of the actual plant protection product. Moreover, there is a monitoring programme to make sure the pesticide residues in food are below the limits set by the regulatory authorities.

[0006] Some measures have been taken to use pesticides more safely, to reduce their use and develop less damaging pesticides. Further, when renewal of approvals of existing pesticides becomes necessary, the “old” synthetic pesticides often face stricter approval regulations and may even be rejected.

[0007] However, there still exists a need to reduce the risks and impacts of pesticide use on human health and on the environment and to promote the use of alternative approaches, such as non-dangerous, more natural chemicals.

[0008] Relevant documents addressing the above-mentioned drawbacks and issues have not been found. KR 100346313 discloses dissolving dried powdered rosin in alcohol and using the obtained solution as a red pepper anthracnose control agent. WO 2016/116668 A1 discloses an oil-in-water dispersion comprising coniferous resin acids and suggests its use as a biocide or pesticide against potato blight. CN 102217621 discloses use of a combination of copper rosinate and pyraclostrobin (a fungicide) to control plant disease caused by various fungi and bacteria. US 5728740 A relates to a method wherein bacterial infections of plants are treated by applying to a plant a composition comprising xylene and a wood rosin. [0009] In the view of the aforementioned discussion, there exists a need to overcome the aforementioned drawbacks and risks associated with use of chemicals to defend plants and crops from pathogens and microbes.

SUMMARY OF THE INVENTION

[0010] The invention is defined by the features of the independent claims. Some specific embodiments are defined in the dependent claims.

[0011] The present disclosure seeks to provide a solution to the existing problem of protecting plants from microbial pathogens, particularly from fungi, without causing harm to the plant or the environment. A further aim is to provide a solution to the existing problem of how to be able to protect plants as often as necessary or required, i.e. to enable repeated use of the treatment as often as necessary and also close to the time of harvesting. Moreover, an aim of the present invention is to provide a solution to the problem of preparing a composition that provides an effective residence time when applied to plants.

[0012] The present invention is based on the concept of using a composition comprising rosin and at least one solvent for treatment of plants, typically crop plants.

[0013] According to a first aspect of the present invention, there is provided a method for antifungal treatment of plants, wherein the method comprises the steps of providing a composition of rosin as antifungal agent, at least one solvent, and at least one auxiliary agent, and applying the composition on the plants or parts of plants, wherein the composition comprises an amount of rosin, which is 0.5-20% by weight of the total weight of the composition.

[0014] According to a further aspect of the present invention, there is provided an antifungal composition consisting essentially of rosin as an antifungal agent, at least one solvent and at least one auxiliary agent, wherein the concentration of rosin is 0.51-50%, preferably 1-20%, by weight of the total weight of the composition.

[0015] Embodiments of the invention substantially eliminate or at least partially address the aforementioned problems in the prior art, and provide a composition that is effective in concentrations smaller and significantly safer as compared to conventional products for its use in treating plants for protecting said plants from pathogens and microbes in the environment. [0016] Considerable advantages are obtained by the invention. First, the composition and the method of the invention reduce the growth of plant pathogens, particularly the growth of fungi. The compositions comprising rosin also modify the structure and formation of spores of some species of fungi.

[0017] Second, the compositions have no adverse effect on the growth of plants. On the contrary, in some studies the compositions comprising rosin had a beneficial effect on the growth of the plants.

[0018] Third, the impact on the growth of plant pathogens may be achieved even at low concentrations of rosin for a relatively long period of time, as compared to substantially high concentrations needed when synthetic pesticides are used.

[0019] Moreover, by using the rosin containing compositions it is possible to repeat the treatment as many times as necessary, whereas the use of current synthetic pesticides is limited by regulatory authorities, for example to at most 4-6 times per season when the composition is applied on growing plants. Further, use of synthetic pesticides is not allowed near the time of harvesting, typically several days or several weeks before harvesting, depending on the pesticide in question. By contrast, the use of rosin containing compositions is allowable regardless of the time of harvesting, without adverse effects on the harvested products.

[0020] Although the method of the invention is particularly applicable for treating growing plants or parts of plants, the compositions containing rosin may also be applied to harvested products, such as fruit, to protect the harvested products from microbes and to increase their shelf life. It is also possible to treat tubers or bulbs before planting to protect them from microbes, particularly fungi, and thus to secure a good start for growing.

[0021] As a natural ingredient rosin is remarkably less harmful than commercially available pesticides and therefore suitable for use for protecting plants without leading to any unpredictable environmental interactions. Further, in the field trials with potato it has been found that the rosin acids (in ionized form) are not carried to tubers after treatment of the growing plants. Thus the exposure of consumers to the active agent may be minimized and any negative effects avoided.

[0022] Further features and advantages of the present technology will appear from the following description of some embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIGURES 1A to 1C are graphical representations of average growth of fungi that is grown for a predefined period of time, in different concentrations of composition comprising rosin and at least one solvent, under dark conditions, in accordance with an embodiment of the present disclosure.

[0024] FIGURES 2A to 2E are graphical representations of average growth of fungi that is grown for a predefined period of time, in different concentrations of composition comprising rosin and at least one solvent, exposed to near visible ultraviolet (NUV) light, in accordance with another embodiment of the present disclosure.

[0025] FIGURE 3 is a graphical representation of development of late blight epidemic in potato during a field trial (Field trial 1).

[0026] FIGURE 4 is a graphical representation of total and ware quality tuber yield and starch content after a field trial of potato (Field trial 1).

[0027] FIGURE 5 is a graphical representation of the progress of late blight in potato during a field trial (Field trial 2). The product according to the invention (Product A) showed a clear dose response.

[0028] FIGURE 6 illustrates starch content of potatoes harvested after Field trial 2.

[0029] FIGURE 7 is a graph showing tuber yield (upper bars) and starch yield (lower bars) after Field trial 2. All fungicide treatments increased the tuber yield when compared to the untreated control.

[0030] FIGURE 8 shows diameter (mm) of different fungal colonies after 3, 7 and 10 days’ incubation, when the efficacy of a rosin composition (Product A) against plant pathogenic Fusarium species was tested in vitro.

[0031] FIGURE 9 illustrates average fungal colony growth rate (mm/day) from the edge of the fungal plug after 3 days’ incubation when the efficacy of a rosin composition against plant pathogenic Fusarium species was tested in vitro. EMBODIMENTS

[0032] In one aspect, the invention provides a method for antifungal treatment of plants, wherein the method comprises the steps of providing a composition of rosin as an antifungal agent, at least one solvent and at least one auxiliary agent, and applying the composition on the plants or parts of plants, wherein the composition comprises an amount of rosin, which is 0.5-20 % by weight of the total weight of the composition.

[0033] In a further embodiment, the invention comprises antifungal compositions consisting essentially of rosin as an antifungal agent, at least one solvent and at least one auxiliary agent, wherein the concentration of rosin is 0.51-50%, preferably 1-20%, by weight of the total weight of the composition

[0034] In the present context, the term “rosin” refers to a resin acid fraction obtained from distillation of coniferous tree oil (typically tall oil) obtained as a by-product from kraft- pulping of coniferous trees. The rosin is enriched with various resin acids but is substantially free of lignans and coumaric acids present in native callus resin, which is exuded from the callus tissue on wounded surface of tree trunks of conifers. Typically, rosin contains 97-99% (w/w) of coniferous resin acids. The rosin may contain minor amounts of fatty acids, typically 1-3% (w/w) of fatty acids.

[0035] The term "rosin" as used herein refers to a solid form of a plant-based ingredient 'resin' obtained, generally, from coniferous trees and pines. Rosin possesses antimicrobial, antibacterial, antifungal and antiviral properties and can be used in protecting plants from various bacteria, viruses and fungi present in the environment surrounding the plant treated with the rosin. It will be appreciated that naturally existing rosin comprises various bioactive ingredients, such as acids and other derivatives. Typically, rosin exists in nature in either a solid form or free form. The rosin is readily soluble in some solvents, such as an organic solvent. Notably, such solvents are highly volatile and evaporate with relative ease, resulting in formation of a protective layer of rosin around the plants treated with the composition comprising rosin, particularly free rosin acid, and at least one solvent.

[0036] “Coniferous resin acids” are organic acids included in rosin. Said acids include resin acids, such as abietic acid, dehydroabietic acid, palustric acid, isopimaric acid, pimaric acid, dihydroabietic acids, further hydroxylated derivatives of dehydroabietic acid and mixtures thereof. [0037] In the present context, terms “plant treatment” or “treatment of plants” refer to treatment of plants or parts of plants, such as foliage, fruit, tubers, bulbs, stolons and rhizomes, preferably foliage, fruit, tubers and bulbs, unless otherwise indicated. The plants or parts thereof may be treated before planting, during growth, after harvesting, or in any combinations thereof, preferably during growth or after harvesting, more preferably during growth. However, treatment of seeds (seed dressing) of grains or cereals before sowing is excluded.

[0038] Within the scope of the present invention, “plants” or “crops” include but are not limited to cereals, fruit or fruit trees, berries, vegetables, and other cultivated plants or crops. The method for treatment of plants thus includes plants such as wheat, barley, rye, oats, rice, com, spelt, sorghum; apple, plum, pear, peach, citrus, orange, mandarin orange, lime, grapefruit, grape, banana, cooking banana, pineapple, mango; cucumber, watermelon, melon, tomato, carrot, beetroot, turnip, rutabaga (yellow turnip), spinach, celery, red pepper, eggplant, garlic, onions, leek, cabbages, lettuce, beans (e.g. broad bean, faba bean), peas, dill, parsley, potato, strawberry, raspberry, highbush blueberry, blackcurrant, redcurrant, whitecurrant, gooseberry; olives, field com, reed canary grass, sweet potato, sugar cane, sugar beet, yam, cassava, soybean, peanut, turnip rape, sunflower, linseed, rapeseed, tobacco, tea, cocoa, coffee, cultivated grass (Poaceae) and legume.

[0039] In an embodiment of the invention, particularly interesting plants to be treated by the compositions comprising rosin include but are not limited to potato, sweet potato, banana, cooking banana, coffee, wheat, barley, rye, oats, rice, com, apple, beans, olives, cocoa, soybean, onions and grape. A preferred plant to be treated by the method and compositions of the invention is potato. Potato is typically treated by applying the composition on the leaves or foliage of a growing potato plant. In one embodiment potato tubers are treated before planting by applying the composition on the tubers to be planted.

[0040] It will be appreciated that plants are subjected to growth of fungus thereon, such as, during exposure to environmental conditions during various stages of plant growth, ranging from seed germination to fruit- formation. The risk of fungal diseases of plants is affected by weather conditions during the crop life and as well as crop location.

[0041] Throughout the present disclosure, the term "fungus" or "fungi" as used herein, refers to a group of eukaryotic organisms that include microorganisms such as yeast, moulds and mushrooms. Fungi are the most widely distributed organisms on earth and exist in either free-form in soil, air and water or in symbiotic relationships with other organisms, such as plants, animals, parasites, other fungi and humans, for their nutritional needs. Fungi have long been used as a source of human food and in processing thereof Moreover, fungi have been employed in production of antibiotics and various industrial applications, such as detergents. Despite the benefits, some bioactive compounds produced by fungi are toxic to plants, animals and humans. Typically, the plants inherently produce antifungal compounds, such as resins, gums, phytotoxins, polyphenols, saponins, fatty acids, essential oils, flavonoids, peptides and so forth, to resist the fungal infections. However, it will be beneficial to identify and exercise preventive measures for combating the fungal growth on the plants.

[0042] In some embodiments of the invention, use of the compositions comprising rosin is particularly effective against fungi selected from Fusarium sp, Ustilago sp, Pyrenophora sp, Phytophthora sp, Botrytis sp, Bipolaris sp, Stagonospora sp, Drechslera sp, Magnaporthe sp and Aspergillus sp. Examples of species from the above mentioned genus include but are not limited to Fusarium oxysporum, f. sp cubense, Fusarium graminearum, Phytophthora infestans, Botrytis cinerea, Pyrenophora teres, Pyrenophora chaetomioides, Pyrenophora avenae, Pyrenophora graminae, Ustilago avenae, Ustilago nuda, Bipolaris sorokiniana, Stagonospora nodorum, Drechslera teres, Magnaporthe oryzae, Magnaporthe grisea, Aspergillus flavus and Aspergillus parasiticus.

[0043] In some embodiments, the method and the composition of the invention are particularly effective against Phytophthora infestans, Fusarium sp and Aspergillus sp, for example Aspergillus flavus and Aspergillus parasiticus. In particular, the method and the composition of the invention are effective against Phytophthora infestans, which causes late blight of plants, typically potato and tomato. Moreover, the method and the composition of the invention are effective against several Fusarium species, which cause i.a. fusarium wilt (Panama disease), basal root rot of e.g. onion, and Fusarium head blight, crown and root rot on cereals.

[0044] The present disclosure provides use of the composition comprising rosin and the at least one solvent and the at least one auxiliary agent for treatment of plants. Throughout the present disclosure, the term "composition" as used herein refers to a plant growth regulating agent that is applied externally to the surface of a plant, such as by spraying, dusting or dipping the plant therein and so forth. It will be appreciated that the term "plants" as used herein refers to a plant in whole or in parts, such as foliage, fruit, tubers, bulbs, stolons, rhizomes, root, stem, flowers, leaves and so forth, preferably foliage, fruit, tubers, bulbs and leaves.

[0045] Optionally, the rosin is in a form of free rosin acid or in a form of its alkali metal, earth alkali metal, pyridine, triethanolamine, ammonium or amine salt or in a form of a mixture of free rosin acid and its salt, particularly alkali or earth alkali metal salt. In one embodiment, the composition comprises a mixture of free rosin acid and an alkali metal, earth alkali metal, ammonium or amine salt of free rosin acid, preferably a mixture of free rosin acid and an alkali metal salt thereof. In a preferred embodiment, the rosin is essentially in the form of a water-soluble alkali or earth alkali metal salt thereof, preferably in the form of sodium salt of rosin.

[0046] More optionally, the free rosin acid comprise largely abietic acid, pyroabietic acid, dehydroabietic acid, 7a-hydroxydehydroabietic acid, 7P-hydroxy dehydroabietic acid, 15- hydroxydehydroabietic acid, 7a, 15 -hydroxy dehydroabietic acid, 7b, 15- dihydroxydehydroabietic acid, 18-hydroxydehydroabietic acid, pimaric acid, sapinic acid and the like rosin acids and/or mixtures thereof, and the alkali metal salt of rosin comprise for example a sodium salt of rosin, potassium salt of rosin, and the like. Furthermore, commercially available form of rosin, i.e. tall oil rosin comprises rosin in the form of at least one of the free rosin acid or the sodium salt of rosin.

[0047] The biological activity of the free rosin acid and the alkali metal salt, particularly the sodium salt of rosin are typically identical. However, the sodium salt of rosin is soluble in water while the free rosin acid in solid form is insoluble in water. Furthermore, the insolubility of solid form of rosin in water contemplates the use of a solvent, such as an organic solvent, including but not limited to, an acetic acid, an alcohol, turpentine, and acetone, that dissolves the rosin. As mentioned earlier, the solvent may also be water. For example, the composition may comprise a commercially available rosin, such as the tall oil rosin (CAS-number 8050-09-7), and at least one alcohol. The composition may also comprise (in addition or alternatively) an ammonium or amine salt of rosin. Preferably, the composition is in the form of a solution.

[0048] Moreover, differences in physical and chemical properties of both the free rosin acid and the alkali metal salt of rosin may be used and combined in an appropriate manner, to provide an overall protection to the plant. In an embodiment, the composition comprises a combination of the free rosin acid and the alkali metal salt of rosin, at least one solvent, such as aqueous alcohol, particularly in such amounts that both the free rosin acid and the alkali metal salt or rosin are soluble, and at least one auxiliary agent. It will be appreciated that the use of the composition comprising rosin, at least one solvent, and at least one auxiliary agent for treatment of plants requires subjecting the plants to such composition. Preferably, the composition comprising both forms of rosin and at least one solvent when applied to the plant results in a dual benefit to the plant. In an example, the composition comprising rosin, particularly in the free acid form, the at least one solvent, and the at least one auxiliary agent, when used for plant treatment, the at least one solvent evaporates over a period of time leaving behind a protective coating of free rosin acid around the plant, while the alkali salt of rosin, such as for example a sodium salt of rosin, preferably provides its antimicrobial effect also to the environment surrounding the plant, such as the soil around the growth medium in a hydroponics arrangement for growing plants.

[0049] The amount of rosin may be from 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7,

7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5,

18, 18.5, 19, 19.5, 20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5, 24, 24.5, 25, 25.5, 26, 26.5, 27, 27.5,

28. 28.5, 29, 29.5, 30, 30.5, 31, 31.5, 32, 32.5, 33, 33.5, 34, 34.5, 35, 35.5, 36, 36.5, 37, 37.5,

38, 38.5, 39, 39.5, 40, 40.5, 41, 41.5, 42, 42.5, 43, 43.5, 44, 44.5, 45, 45.5, 46, 46.5, 47, 47.5 or 48 wt-% up to 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5,

11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, 20.5,

21, 21.5, 22, 22.5, 23, 23.5, 24, 24.5, 25, 25.5, 26, 26.5, 27, 27.5, 28, 28.5, 29, 29.5, 30, 30.5,

31, 31.5, 32, 32.5, 33, 33.5, 34, 34.5, 35, 35.5, 36, 36.5, 37, 37.5, 38, 38.5, 39, 39.5, 40, 40.5,

41, 41.5, 42, 42.5, 43, 43.5, 44, 44.5, 45, 45.5, 46, 46.5, 47, 47.5, 48.5, 49, 49.5 or 50 wt-% of the total weight of the composition. More optionally, the amount of rosin is 5-25 wt-% of the total weight of the composition. The amount of rosin may be from 5, 5.5, 6, 6.5, 7,

7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5,

18, 18.5, 19, 19.5, 20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5 or 24 wt-% up to 6, 6.5, 7, 7.5, 8,

8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18,

18.5, 19, 19.5, 20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5, 24.5 or 25 wt-%. It will be appreciated that higher concentrations of rosin provide enhanced protection to the plant as compared to lower concentrations of rosin. However, such higher concentrations of the rosin may lead to increased precipitation during sample preparation, and may thus result in formation of larger precipitates. [0050] Typically, the composition comprising rosin as an antifungal agent, at least one solvent, and at least one auxiliary agent is provided as a concentrate or stock solution, which is diluted prior to use to the required or desired concentration. The concentration of rosin in the stock solution is typically about 15 to 25% (w/w), preferably 15 to 20% (w/w), and more preferably about 17% (w/w). The stock solution may contain any auxiliary agents needed, such as buffering agents and solubility affecting agents.

[0051] Before application, the concentrate or stock solution of the composition is diluted to a required concentration needed for the treatment of certain plants or parts of plants. To avoid any precipitate formation, the concentrate or stock solution is preferably first heated, typically to 50-60°C or to 70-80°C, followed by slowly adding the heated solution with vigorous mixing to water. The resulting solution is allowed to cool to room temperature, where it remains clear for several days. Formation of precipitates is not desirable since any precipitate in the solution may cause blockage of the spraying nozzles of the application means.

[0052] Depending on the particular plant in question, the application rate may be given for example as the amount of stock solution or active agent to be applied per hectare (as in the case of cereal crops) or as the dilution rate for preparing a dilute spraying solution (as in the case of fruit). Preferably, the stock solution is diluted in water, for example by mixing the required amount of the concentrate or stock solution in 200 to 500 litres of water to be applied per hectare. In a preferred embodiment, rosin in the stock solution consists essentially of sodium salt of rosin, which is soluble in water.

[0053] In one aspect, an embodiment of the present disclosure provides a composition comprising rosin, in particular an alkali salt of rosin, at least one solvent, such as alcohol or water, and at least one auxiliary agent, wherein the amount of rosin is 0.5-20 wt-%, preferably 0.5-10 wt-%, of the total weight of the composition, such as for example 0.5-5 wt-% or 1-5 wt% of the total weight of the composition. The invention also provides use of said composition in the method of the invention.

[0054] In an example, the amount of rosin may be 1-3 wt-% of the total weight of the composition. In such a case, limiting the concentration of rosin to 1-3 wt-% of the total weight of the composition results in lower precipitation of rosin and enables effective antimicrobial activity of the rosin. It will be appreciated that rosin at a concentration of 3 wt-% is more effective in protecting the plants as compared to rosin used at a concentration of 1 wt-% of the total weight of the composition, while bearing in mind that for some applications, 1 wt-% may be fully sufficient as a preferable amount of rosin.

[0055] In an embodiment of the invention, the rosin comprises or consists essentially of abietic acid, dehydroabietic acid, palustric acid, isopimaric acid, pimaric acid, dihydroabietics acid, neoabietic acid, 13-b-7,9(1 l)-abietic acid, 8.12-abietic acid, 7,9(11)- abietic acid, sandaracopimaric acid, 8,15-pimaric acid, 8,15-isopimaradien-18-oic acid, levopimaric acid and combinations thereof

[0056] In a further embodiment of the invention, the rosin comprises at least 38 wt-% abietic acid, typically at least 40 wt-% abietic acid, and at least 15 wt-% dehydroabietic acid, based on the total weight of the rosin.

[0057] In a still further embodiment of the invention, the rosin comprises 38-45 wt-% abietic acid, 15-22 wt-% dehydroabietic acid, 7-12 wt-% palustric acid, possibly with 3-6 wt-% isopimaric acid, 2-5 wt-% pimaric acid, 3-5 wt-% dihydroabietics acid (group), and 3-5 wt-% neoabietic acid, based on the total weight of the rosin, and further optionally with minor amounts of other abietic acids or pimaric acids.

[0058] Optionally, the at least one solvent is at least one alcohol. It will be appreciated that presence of free rosin or its derivatives that are insoluble or partly soluble in water may generate the need for use of the at least one solvent, which is capable to dissolve rosin, such as alcohol. Specifically, the at least one alcohol enables increased solubility of the rosin. More optionally, the at least one alcohol is selected from ethanol and isopropanol. It may also be a mixture of ethanol and isopropanol, at various ratios, such as comprising ethanol and isopropanol. Furthermore, ethanol, isopropanol and/or combination thereof are safe to be sprayed on plants or any part thereof. In some embodiments, the at least one solvent may, in addition to those mentioned above, be selected from other non-aromatic solvents, typically from dimethyl sulfoxide, propylene glycol, glycerol, other polyalcohols, and their combinations. Preferably, aromatic solvents are not included.

[0059] Furthermore, optionally the solvent is used at a concentration of 5-70 wt-%. It will be appreciated that the composition comprising rosin and at least one solvent, such as at least one alcohol, may be used for plant treatment in a concentrated or a diluted form. The weight percentage of rosin and the at least one alcohol is in a range of 0.5-50 wt-%, more preferably 5-25 wt-%, and 5-70 wt-% of the total weight of the composition. In an example, the amount of at least one alcohol may be from 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12,

12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, 20.5, 21, 21.5,

22, 22.5, 23, 23.5, 24, 24.5, 25, 25.5, 26, 26.5, 27, 27.5, 28, 28.5, 29, 29.5, 30, 30.5, 31, 31.5,

32, 32.5, 33, 33.5, 34, 34.5, 35, 35.5, 36, 36.5, 37, 37.5, 38, 38.5, 39, 39.5, 40, 40.5, 41, 41.5,

42, 42.5, 43, 43.5, 44, 44.5, 45, 45.5, 46, 46.5, 47, 47.5, 48, 48.5, 49, 49.5, 50, 55.5, 56, 56.5,

57, 57.5, 58, 58.5, 59, 59.5, 60, 60.5, 61, 61.5, 62, 62.5, 63, 63.5, 64, 64.5 or 65 wt-% up to

10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5,

20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5, 24, 24.5, 25, 25.5, 26, 26.5, 27, 27.5, 28, 28.5, 29, 29.5,

30, 30.5, 31, 31.5, 32, 32.5, 33, 33.5, 34, 34.5, 35, 35.5, 36, 36.5, 37, 37.5, 38, 38.5, 39, 39.5,

40, 40.5, 41, 41.5, 42, 42.5, 43, 43.5, 44, 44.5, 45, 45.5, 46, 46.5, 47, 47.5, 48, 48.5, 49, 49.5,

50, 55.5, 56, 56.5, 57, 57.5, 58, 58.5, 59, 59.5, 60, 60.5, 61, 61.5, 62, 62.5, 63, 63.5, 64, 64.5,

65.5, 66, 66.5, 67, 67.5, 68, 68.5, 69, 69.5 or 70 wt-% of the total weight of the composition.

[0060] Optionally, the at least one auxiliary agent is selected from surface active agents, viscosity modifying agents, adsorption modifying agents, wetter-spreaders, stickers, emulsifiable oil activators, foliar nutrients, compatibility agents, drift retardants, foam retardants, buffers, plant penetrants, inverting agents, sinking agents, protectant binders, fixing agents, and stabilizing agents, each for example up to 20 wt-%.

[0061] Examples of typical auxiliary agents include surface active agents (for example up to 20 wt-%), agents modifying the viscosity of the composition, such as carboxy methyl cellulose and its derivatives (for example up to 20 wt-%), agents modifying the adsorption of the composition (for example up to 30 wt-%), foam retardants (for example up to 20 wt%), and fixing agents or adhesive agents (for example up to 20 wt-%). In some embodiments concentration of auxiliary agents is 0.1-10 wt-% or 0.5-5 wt-%, for example at most 1-2 wt- %. In one embodiment, the composition comprises surface active agents, which may ease spreading of the composition on the surface of plants or parts of plants.

[0062] In an embodiment, wherein both the free rosin acid and the alkali metal salt of rosin are used, their ratio may be controlled in an appropriate manner, e.g. by adjusting the pH, by the use of buffering agents and/or emulsifying agents. It is to be noted that rosin and the salts of rosin acid, in particular free rosin acid, attach particularly well on the foliage of a plant compared to traditional pesticidal agents, whereby any fixative agents are not needed or their amount can be kept at minimum. In one embodiment, the composition comprises a sufficient amount of free rosin acid to further improve adhesion of the composition on the plant or part(s) of the plant, while the antifungal effect is provided mainly by the salt form of rosin.

[0063] In one embodiment, the composition consists essentially of 0.51 - 20 % (w/w) of rosin, 70-99% (w/w) of at least one solvent and 0.1-10% of at least one auxiliary agent. In a further embodiment the composition comprises free rosin acid and the alkali metal salt of rosin, preferably sodium salt of rosin, in a ratio of 5:95 - 25:75. In one embodiment wherein the rosin comprises both the free rosin acid and the alkali metal salt of rosin, the amount of free rosin acid is about 1-10%, such as 5-10% or even 1-5%.

[0064] Optionally, other components may be added to the composition. More optionally, the other components (or additives) are added to alter a natural composition of ethanol, isopropanol and/or combination thereof, thereby making it more appropriate for use as a solvent. Furthermore, the other components may be added to improve the solubility of the composition. However, it is not desirable to use additives that could also impact growth of plants and/or pathogens on the plants (such as additives that promote growth of pathogens on plants). In addition to an increase in cost of the composition after addition of such other components or additives, repeated use is likely to impact plant growth and/or aggravate harmful environmental interactions, such as promote a harmful change in the atmospheric carbon dioxide concentration around the plants.

[0065] Optionally, pH of the composition is 3-12. It will be appreciated that dissolution of rosin in at least one solvent is subjective to the pH of the solvent. The pH has an effect on the solubility of the sodium salt of rosin into aqueous solutions. Indeed, when the sodium salt of rosin is dissolved in water, its pH is about 10-11. If desired, pH of the solution containing the sodium salt of rosin is lowered to pH 8-10 or to pH 9-10. If the pH is lowered (for example by adding hydrochloric acid) to 7.5-8.5, the rosin may precipitate. Thereafter, it reacts to form its free acid form, alcohol increasing the solubility.

[0066] Furthermore, at a pH of 8, the rosin dissolves completely in the at least one alcohol. It is desirable that pH of the composition is adjusted to about 8 with the addition of a suitable acid or base. A suitable acid or base includes, but is not limited to, 1 molar (1M) sodium hydroxide (NaOH) or 1M hydrochloric acid (HC1), respectively. However, addition of such acids results in formation of precipitates in higher concentrations of the composition. The precipitation may impact the actual concentration of rosin in the total composition, thereby impacting (such as reducing) the growth of pathogens. The pH of the composition may thus be for example from 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10 or 10.5, 11, 11.5 up to 4, 4.5, 5, 5.5, 6, 6.5, 7, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5 or 12.

[0067] The present disclosure provides a method of treating plants. The method comprises a step of providing a solution of rosin, at least one solvent and at least one auxiliary agent. Optionally, a commercially available solid tail-oil rosin (Forchem for90) is dissolved into the at least one solvent, preferably at least one alcohol, more preferably the at least one alcohol selected from ethanol, isopropanol, propylene glycol, polyethylene glycol and glycerol. In case the rosin is in free acid form, it may be converted to salt form, typically to sodium or potassium salt form, for example by dissolving the aforementioned alcohol concentrate to sodium hydroxide or potassium hydroxide solution, with a slight excess or equimolar amount of the base. The final pH may be adjusted with the base and for example hydrochloric acid. Alternatively, a commercially available rosin in alkali metal salt form, such as tail-oil rosin in sodium salt form (e.g. Forchem Forext 35/90), may be used.

[0068] More optionally, the concentration of rosin, such as Forchem For90 or Forext 35/90, is 0.51-50 wt-%, preferably 0.5-25 wt-%, 0.5-20 wt-%, 0.5-10 wt-%, 1-20 wt-% or 5-20 wt- % of the total weight of the composition.

[0069] In one embodiment, the invention also relates to an antifungal composition, which consists essentially of rosin as antifungal agent, at least one solvent and at least one auxiliary agent, wherein the concentration of rosin is 0.51-50 wt-%, preferably 0.5-25 wt-%, 0.5-20 wt-%, 0.5-10 wt-%, 1-20 wt-% or 5-20 wt-% of the total weight of the composition, and wherein the rosin is in the form of an alkali metal salt of free rosin acid or as a mixture of free rosin acid and its alkali metal salt, preferably sodium salt.

[0070] The various embodiments and possible concentrations as given above in connection with the use apply mutatis mutandis to the method.

[0071] Moreover, the concentration is provided to be applied externally to the growing plants. Optionally, the at least one solvent used for dissolving the rosin may be selected from water, ethanol, isopropanol or a combination thereof. In some embodiments, the at least one solvent may also be selected from other non-aromatic solvents, such as dimethyl sulfoxide, propylene glycol, glycerol, other polyalcohols, and their combinations, in addition to those mentioned above. [0072] Furthermore, the method comprises providing a solution of rosin and the at least one solvent and the at least one auxiliary agent and subsequently, applying the solution on the plants.

[0073] A preferred way of applying the solution on the plants is by spraying. The plants are sprayed with the provided solution of rosin and the at least one solvent in a predefined concentration. Notably, spraying at least one of alcohols, selected from ethanol, isopropanol and/or combination thereof, even at substantially higher concentrations, is safer than watering plants with even low concentrations of ethanol, isopropanol and/or combination thereof. For example, spraying ethanol at a concentration of up to 70 % may not cause damage to the plant, while watering the plant even with a concentration ranging between 5- 25% of ethanol may result in stressing (at 5 % concentration of ethanol) or death (at 25 % concentration of ethanol) of the plant.

[0074] Alternatively, the external application of the composition to the plants comprises wetting, watering or brushing the plants or parts of the plants with the composition or dipping the plants in the composition.

[0075] When the plants on which the composition has been applied get dry, the at least one alcohol from the provided solution of the rosin and the at least one solvent evaporates. Notably, with the evaporation of the at least one solvent, the water-insoluble free acid form of rosin forms a protective coating around the plant or parts of the plant, which acts as an antifungal agent for the plant. Furthermore, the water-soluble alkali metal salt of rosin may be absorbed in the surrounding ground or soil around the plant, when the composition is applied on a growing plant. Beneficially, the alkali metal salt of rosin acts as an antifungal agent also for the soil surrounding the plant. Moreover, the use of the composition comprising rosin and at least one solvent for plant treatment and method thereof protects the plants from the harmful effects of the pathogens such as fungi.

[0076] The composition comprising rosin and at least one alcohol is used for antifungal treatment of plants. However, the composition may also be used as potential bactericide and so forth, owing to the antimicrobial properties of the rosin and the disinfectant properties of the at least one alcohol. Specifically, the composition is applied externally to the plants or part(s) of the plants. More specifically, the application is for example by way of spraying, wetting, watering or brushing the plants with the composition. Spraying the plants with the composition typically protects the plants from the harmful effects of alcohol on the plants as alcohol evaporates over a period of time, leaving behind a protective coating of the rosin over the plant or part of the plant. Furthermore, along with the antifungal effects of the composition, the pH of 7.5 -8.5 protects the plants from a potential attack from the different species of fungi in the environment (such as ground). Furthermore, the composition comprising both the forms of rosin, i.e. the free rosin acid and the sodium salt of rosin provides protection to the plants and fungicidal effect on the surrounding ground (soil or water, such as in hydroponics arrangement for plant growth) respectively.

[0077] In the method and use according to the invention, plants or parts of plants may be treated with compositions comprising rosin as antifungal agent before planting, during growth, after harvesting, or in any combinations thereof. Application may be repeated as often as needed, for example several times during the growing season when applied to growing plants, or for example 1 to 2 times when applied on bulbs or tubers before planting or when applied on fruit after harvesting. Plants may also be treated immediately before harvesting without adverse effects on the harvested products.

[0078] In an embodiment, the treatment of plants is carried out at least 2, 3, 4, 5, 6, 7, 8, 9, 10 times or as often as required.

[0079] Typically, treatment may be accomplished at such time point(s) of the growing season when risk of fungal diseases is high and when the treatment provides the best possible effects, taking the particular characteristics of the plants in question into account. The treatment may also be accomplished before or after the growing season.

[0080] An example of treatment of plants before planting is antifungal treatment of potato tubers before planting, in particular to protect the tubers from wire stem caused by Rhizoctonia solani. Said plant pathogen typically exists as thread-like growth (hyphae) on plants and causes various plant diseases, such as rattening of the plant. One embodiment of the invention is therefore use of the rosin containing composition for antifungal treatment of potato tubers before planting, wherein the composition is preferably used in an amount of 1- 20 g / kg potato tubers. If necessary, the treatment can be repeated, even several times as explained above.

[0081] Another example of the use of compositions comprising rosin as an antifungal agent for treatment of plants during growing season or after harvesting includes treatment of nuts and cereal crops. Specifically, the growth of Aspergillus flavus and Aspergillus parasiticus in nuts and cereal crops after harvesting (grains) is known to produce carcinogenic aflatoxins and therefore the prevention of the growth of said fungi is particularly desired. One embodiment of the invention is therefore use of the rosin containing composition for antifungal treatment of nuts and cereal crops, particularly after harvesting to prevent growth of Aspergillus sp, more particularly Aspergillus flavus and Aspergillus parasiticus.

[0082] One preferred embodiment of the use of compositions comprising rosin as an antifungal agent is treatment of late blight, in particular late blight of potato. Late blight ( Phytophthora infestans) is a potentially devastating disease that can infect potato foliage and tubers or tomato plants at any stage of crop development. The risk of disease is affected by weather conditions during the crop life and by crop location. Humid and sufficiently warm conditions increase blight risk. When plants have become infected, first symptoms appear as lesions on the leaves and stems. Late blight infection of tubers is characterized by irregularly shaped discoloured areas and rot under said areas.

[0083] An embodiment of the invention is thus a method for treatment and prevention of late blight of potato, wherein a composition, which comprises rosin as an antifungal agent, at least one solvent, and at least one auxiliary agent, is applied on the potato tubers before planting or on the foliage of growing potato plants or both, preferably on the foliage of growing potato plants. The concentration of rosin in the composition for use in the treatment and prevention of late blight of potato is 0.5 -20 wt-%, preferably 0.5-10 wt-%, more preferably 1-5%, of the total weight of the composition. In one embodiment, the composition is applied on foliage and leaves of growing potato plants in an amount of 3 - 15 kg of undiluted (100%) rosin /ha.

[0084] In an embodiment, the treatment of growing plants, preferably growing potato plants, is repeated as often as necessary, for example at least 4 times, such as for example 4-6 times, or at least 6, 7, 8, 9 or 10 times. The treatment may be carried out close to harvesting, such as less than 3 days before harvesting, or even on the harvesting day.

[0085] The invention also provides compositions, which consist essentially of rosin as an antifungal agent, at least one solvent and at least one auxiliary agent for use in antifungal treatment of growing plants, wherein the amount of rosin is preferably 0.5 to 25% by weight of the total weight of the composition. [0086] The compositions of the invention are effective against various phytopathogenic fungi. Typically, the compositions of the invention provide an antifungal effect against species from Fusarium sp, Ustilago sp, Pyrenophora sp, Phytophthora sp, Botrytis sp, Bipolaris sp, Stagonospora sp, Drechslera sp,, Magnaporthe sp and Aspergillus sp. In particular, the compositions comprising rosin have prohibited the growth of fungal species Fusarium oxysporum, f. sp cubense, Fusarium graminearum, Phytophthora infestans, Botrytis cinerea, Pyrenophora teres, Pyrenophora chaetomioides, Pyrenophora avenae, Pyrenophora graminae, Ustilago avenae, Ustilago nuda, Bipolaris sorokiniana, Stagonospora nodorum, Drechslera teres, Magnaporthe oryzae, Magnaporthe grisea, Aspergillus flavus and Aspergillus parasiticus. Significant results have been been obtained for example in the prevention of late blight of potato, caused by Phytophthora infestans.

[0087] It is to be understood that the embodiments of the invention disclosed are not limited to the particular structures, process steps, or materials disclosed herein, but are extended to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It should also be understood that terminology employed herein is used for the purpose of describing particular embodiments only and is not intended to be limiting.

[0088] Reference throughout this specification to one embodiment or an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Where reference is made to a numerical value using a term such as, for example, about or substantially, the exact numerical value is also disclosed.

[0089] As used herein, a plurality of items, structural elements, compositional elements, and/or materials may be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no individual member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presentation in a common group without indications to the contrary. In addition, various embodiments and example of the present invention may be referred to herein along with alternatives for the various components thereof. It is understood that such embodiments, examples, and alternatives are not to be construed as de facto equivalents of one another, but are to be considered as separate and autonomous representations of the present invention. [0090] Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided, such as examples of lengths, widths, shapes, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

EXPERIMENTAL

[0091] Antifungal effect on plate culture

[0092] The antifungal properties of the composition were used for preventing growth of fungus on the plants. In this regard, different species of fungi were grown in potato dextrose agar (indicated as 'PDA' hereafter) powder (comprising agar and nutrients for growth of fungi) for a period of 4 days at a temperature of +18°C. The cultured species of the fungi having a diameter of 7 mm or more were inoculated and their growth was monitored in a sample comprising dried form of rosin, optionally the sodium salt of rosin, and PDA. Such sample of rosin and PDA was dissolved in cold water and pH of the resulting mixture was adjusted to about 8, by adding a suitable acid or a base thereto. Furthermore, the resulting first sample was heated in an autoclave maintained at a predefined temperature of 121 °C. It was observed that, at such a high temperature the precipitates formed in the composition had ceased to exist. However, the precipitation in the composition continued to occur at room temperature (about 20 °C).

[0093] In one test, the fungus was selected from a group comprising Botrytis cinerea, Pyrenophora teres, Bipolaris sorokiniana, Stagonospora nodorum, Fusarium graminearum and Fusarium avenaceum. It will be appreciated that other species of fungi having similar characteristics including, but not limiting to, colour, formation of spores, structure and density, may also be selected. The six species of fungi were grown under dark conditions at +18 °C and at 3 different concentrations of rosin, i.e. 0 wt-% (i.e. absence of the rosin in the first sample or “ control ”), 1 wt-% and 3 wt-%. Subsequently, the average growth of fungi was recorded for a period of 4, 8 and 14 days after anthesis (DAA) at each concentration. The different concentrations of the rosin were used to test the effect of the rosin on the growth of fungi. It was observed that presence of rosin had a significant impact on the growth of all the aforementioned species of fungi. Moreover, the stronger concentration i.e. 3 wt-% concentration of rosin prohibited the growth of fungal species Pyrenophora teres, Bipolaris sorokiniana, Stagonospora nodorum and Fusarium graminearum until the 8 ^th day and 14 ^th day. However, the fast-growing species of fungi, namely, Botrytis cinerea and Fusarium avenaceum, also demonstrated a significant reduction in growth at 3 wt-% concentration of rosin. Notably, even at 1 wt-% concentration of rosin, the growth of fungi was significantly reduced or substantially prohibited for all the aforementioned species of fungi. Furthermore, higher concentrations of rosin had an effect on weakening the spreading and conservation of the aforementioned species of the fungi.

[0094] It will be appreciated that the rosin has an impact not only to reduce the growth of the fungi, but also in modifying structure and formation of spores of some species of fungi. In an example, based on a visual study, the growth of fungus Fusarium graminearum was abundant and lint-like in the control sample, while in the sample with rosin, the growth of the fungi was dense and observed to be located only at the surface of the sample. In another example, fungus Botrytis cinerea formed several sclerotium in the control sample, while the presence of rosin prohibited the formation of sclerotium until the 8 ^th day and 14 ^th day. However, the formation of sclerotium was observed after the 14 ^th day at the 1 wt-% concentration of rosin.

[0095] Moreover, colour of some species of the fungi may be a measure of the growth of fungi in a sample. In an example, the fungus Bipolaris sorokiniana exhibited black spots containing a significant number of conidium, while in the samples comprising rosin at any concentration, the fungal growth was lighter in colour and contained no or negligible conidium. Furthermore, presence of the rosin significantly limited the formation of spores in fungal species, such as Pyrenophora teres, Stagonospora nodorum and Fusarium avenaceum.

[0096] The test results are shown in FIGs. 1A, IB and 1C, as graphical representations of average growth of fungi. The different species of fungi were grown in different concentrations of compositions under dark conditions, as explained above, for a predefined period of time. As shown, the Y-axis (vertical axis) of the graphs represent the average growth of fungi in millimetres (mm). The X-axis (horizontal axis) of the graphs represent the different species of fungi Botrytis cinerea (depicted as species code T), Pyrenophora teres (depicted as '2'), Bipolaris sorokiniana (depicted as '3'), Stagonospora nodorum (depicted as '4'), Fusarium graminearum (depicted as '5') and Fusarium avenaceum (depicted as '6'). In each FIG., for each species of fungi, the left-most column is the result at 4 days, the middle column is the result at 8 days and the right-most column the result at 14 days. The same applies for FIG. 1A to 1C.

[0097] As shown in FIG. 1 A, the different species of fungi grew normally under control conditions, i.e. when the concentration of rosin was 0 wt-%. However, addition of rosin in each sample of fungi resulted in a significant impact on the growth of fungus, as shown in FIGs. IB and 1C. At the concentration of 3 wt-%, rosin prohibited the growth of all species of fungi until 8 days and 14 days. Moreover, only the fastest growing species of fungi, such as Botrytis cinereal and Fusarium avenaceum were able to grow despite the stronger concentration of rosin.

[0098] In another exemplary implementation, four species of fungi, namely, Botrytis cinereal, Pyrenophora teres, Bipolaris sorokiniana and Fusarium avenaceum, were grown at +18°C and at five different concentrations of rosin. Furthermore, the different species of fungi were grown by exposure to near visible ultraviolet (NUV) light for 12 hours per day and the growth of fungi was measured at the 3 ^rd day and the 6 ^th day of culture. It was observed that presence of rosin had a significant impact on the growth of all the four species of fungi. Furthermore, even the lower concentrations of 0.5 wt-% or 1 wt-% had a significant impact on the growth, when compared to the control sample (0 wt-%). However, the growth of fungi could not be significantly observed at higher concentrations, i.e. 2 wt-% and 3 wt- % of the rosin, due to the precipitation of the rosin at such concentrations.

[0099] The results are shown in FIGs. 2A to 2E as graphical representations. As shown the Y-axis (vertical axis) of the graphs represent the average growth of fungi in millimetres (mm). The X-axis (horizontal axis) of the graphs represent the different species of fungi, namely Botrytis cinerea (depicted as species code T), Pyrenophora teres (depicted as '2'), Bipolaris sorokiniana (depicted as ’3’) and Fusarium avenaceum (depicted as ’6’). The average growth of fungi was recorded for a period of 3 and 6 days after anthesis (DAA) at each concentration of 0 wt-%, 0.5 wt-%, 1 wt-%, 2 wt-% and 3 wt-% of rosin as shown in FIG. 2A, FIG. 2B, FIG. 2C, FIG. 2D and FIG. 2E respectively. In each FIG., for each species of fungi, the left column is the result at 3 days and the right column the result at 6 days.

[00100] FIG. 2A shows that the different species of fungi grew normally under control conditions, i.e. when the concentration of rosin is 0 wt-%. However, addition of rosin in each sample of fungi resulted in a significant impact on the growth of fungus, as shown in FIGs. 2B to 2E. At the concentration of 0.5 wt-% and 1 wt-%, presence of rosin substantially reduced the growth of all species of fungi as compared to the control. Moreover, the differences between the samples at higher concentrations, i.e. 2 wt-% and 3 wt-%, prohibited the growth of some species of fungi until 3 days, however, at the end of 6 days, due to precipitation of rosin at higher concentrations, the reduction in growth of such fungi was substantially impacted.

[00101] Exemplary composition (Field trial 1)

[00102] Product A was provided as a concentrate containing 170 g/1 (17% w/w) active agent (rosin). For the control of foliar blight and tuber blight ( Phytophtora infestans) in potatoes in field trial, the dose was estimated to be 10 L/ha, based on earlier trials. For application, the concentrate was mixed with clean water to obtain 300 L of liquid for spraying. The concentration of the active agent in the liquid for spraying was thus about 0.57% (w/w).

[00103] Field trial 1- potato

[00104] To determine the efficacy of Product A in control of late blight in potato, field trials were carried out. The purpose of the trial was to evaluate the biological efficacy of Product A on potato late blight caused by Phytophthora infestans. The conduct of the trial was based on the standards for the efficacy evaluation of plant protection products as determined by the EPPO (European and Mediterranean Plant Protection Organization). The field trial was performed at Ylistaro in Seinajoki, Finland, by Natural Resources Institute Finland, in co-operation with Potato Research Institute.

[00105] Product A (170 g/1) was tested at the rate of 10 l/ha. The efficacy of Product A was compared to untreated controls and to a standard product Shirlan® that is commonly used to control late blight. Shirlan® is a suspension concentrate that contains fluazinam 500 g/1 as an active ingredient. It was applied according to the manufacturer’s instructions at a rate of 0.4 l/ha.

[00106] Potato cultivar Sieglinde (“Siikli”) was used in this trial. Said cultivar is known to be susceptible to foliar and tuber blight. The trial was planted on June 6 and harvested on September 13, three weeks after the last fungicide treatment. [00107] Fungicides were applied six times with intervals of 6 to 10 days between July 15 and August 22. Fungicides were applied with a plot boom sprayer carried by a tractor. Low drift flat fan nozzles were used in the spraying boom.

[00108] There were four replications in the trial and six potato rows per one trial plot. Four of them were treated and the two middle rows were assessed. The two outermost rows were left without any late blight control. This way an even disease pressure can be ensured across the whole trial.

[00109] The emergence of potatoes was observed at the same time on the whole trial and possible differences were marked. Potato development stage and canopy cover were assessed at each application time. Late blight was monitored once or twice a week. At the time of late blight assessments, phytotoxicity was also monitored and recorded if necessary.

[00110] Tuber samples for quality assessments were collected during the harvest and stored separately to minimize disease contamination between treatments. After the harvest, the yield was graded by tuber size and the starch content was assessed based on under water weight. Tuber blight was observed a week after harvest by sorting diseased tubers from healthy ones. Other possible defects in tubers were also notified if necessary.

[00111] Results: weather conditions and late blight appearance

[00112] Most of the summer the weather was dry. In the middle of August there were some rainy days but the rainfall remained low. Temperatures varied a lot, and the nights were exceptionally cool. In the beginning of August, night frosts damaged the top leaves of potatoes.

[00113] The control programs were started on July 15. First lesions of late blight in the untreated canopy were found on August 22. Late blight spread further quite slowly in the untreated plots. In the plot with the most damage, the disease severity was 15% in the beginning of September and 50% on the day of harvest. In the other untreated plots, late blight destroyed 5-15% of the foliage by harvest.

[00114] Results: control efficacy

[00115] The first lesions of leaf blight were found on the day of last fungicide application (August 22). Rainy weather in early September increased infection pressure and the leaf blight severity finally increased to 13% in the untreated control by September 13. Product A delayed late blight appearance and decreased the disease severity significantly. Its control efficacy was slightly weaker than that of the reference product Shirlan®, which controlled leaf blight completely in the low disease pressure. The results can be seen Figure 3.

[00116] Results: yield and tuber blight

[00117] Leaf blight appeared so late that it did not have a significant effect on tuber yield. The canopies were uneven because of the difficult growing season and night frost damages. Also the tuber yields varied a lot and the differences between the treatments were not significant. The tuber yield in the untreated control was 32.4 t/ha. The tuber yield achieved by the reference product was 2% higher and the yield achieved with Product A was 2% lower when compared to the untreated control. In circumstance that had prevailed these minor differences were insignificant and thus the yield quantities of ah three treatments were on the same level.

[00118] Tuber blight was assessed a week after harvest. In the tuber yield of the untreated control, tuber blight incidence was about 3%. Both fungicide treatments decreased tuber blight slightly. Because of the low incidence of tuber blight and soft rot, the difference between total tuber yield and healthy tuber yield was small. The proportion of ware yield (healthy tubers, 35-70 mm in size) of the Product A was equal to that of the untreated control. The reference product resulted in 6% higher ware potato yield than other treatments. Results are shown in Figure 4.

[00119] Results: other diseases and damages

[00120] Potato canopy was damaged by night frost in the beginning of August. Unfortunately, the damage was not even, and it affected the yield quantities.

[00121] In the late part of the growing season when potatoes were already maturing, symptoms of early blight (. Altemaria solani ) and grey mold ( Botrytis cinered) appeared in the canopy. Because of the variable spots and lesions of different causes, it was time- consuming but possible to observe foliar blight.

[00122] The incidence of tubers damaged by soft rot and tuber blight were assessed at the same time. Soft rot incidence was small in the untreated control and non-existent in the other treatments.

[00123] Results: Conclusions [00124] Late blight risk was low almost the whole season. The reference product (Shirlan®) acted as expected in low disease pressure, by having 100% control efficacy against leaf blight. Product A delayed late blight appearance by one week and achieved final control efficacy of 87%. This means that Product A has fungicidal efficacy against late blight.

[00125] Field trial 2 - potato

[00126] Another field trial with potato was accomplished in the following year after Field trial 1. This time, Product A was tested at water dilutions of 1%, 2% and 4% (w/w), which corresponded to rates 3, 6 and 12 kg of undiluted product per hectare. (The lot of Product A to be used was provided as 34% (w/w), so the product rates correspond to 8.823 kg/ha, 17.646 kg/ha and 35.346 kg/ha of the prediluted product.). Shirlan 0.4 1/ha was included as a standard product in the trial and in addition, an untreated control was randomised within the trial. All fungicides were applied six times with 7 days’ intervals. The disease source was natural infection and untreated rows were used between all plots to ensure an evenly distributed disease pressure across the trial.

[00127] Potato cultivar Sieglinde (“Siikli”) was planted on June 8. Disease control program was started almost three weeks after potato emergence, at potato stem elongation stage. Fungicides were applied for the first time on July 14 ^th and the applications continued with 7 day-intervals until August 18 ^th . Crop stand was assessed weekly, last time on September 7 ^th . Tuber crop was harvested three days after the last efficacy assessment. Haulm desiccation was not used.

[00128] Results

[00129] Leaf blight began to spread rapidly under rainy weather in late August resulting in 99% destruction of leaf area by September 7 ^th in the untreated plots. Shirlan showed 100% control efficacy two weeks and 97% control efficacy three weeks after the last fungicide application. Product A acted well against late blight and showed a clear dose response (Figure 5). Efficacies at the dose rates of 3, 6 and 12 kg/ha were 73%, 85% and 95%, respectively. The efficacies three weeks after the last fungicide applications show that the highest dose had good efficacy persistence (efficacy 75%), the middle rate fair persistence (efficacy 53%) and the lowest rate had a limited persistence (efficacy 25%).

[00130] At harvest, tuber samples were taken by plot for tuber blight assessment and observed the next day. About 100 symptomless tubers were stored and observed second time after four weeks’ storage time. Some tuber blight symptoms were found at harvest and their incidence increased during storing period indicating partially latent infections at harvest time.

[00131] Potato tuber yield was at normal level in the untreated plots. Late blight control increased tuber yield by 9% (Product A at 3 kg/ha) to 14% (Shirlan). Starch content was 16.0% in the untreated control. Shirlan increased starch content by 1.4 %-units and Product A by 0.6-0.8 %-units. Yield increase and starch content correlated positively with control efficacy. Starch content is shown in Figure 6 and tuber and starch yields in Figure 7.

[00132] No phytotoxicity occurred in any of the treatments. No side effects were observed on other organisms. Early blight (Alte maria solani ) was controlled by spraying the whole trial area with the product Narita (difenoconazole) on July 22 ^nd . Early blight remained at very low level and did not affect the trial results.

[00133] To conclude, Product A controlled late blight rather well compared to the standard product, Shirlan, although the control efficacy was not as good as with Shirlan. The dose rates of Product A (3, 6 and 12 kg/ha) showed clear positive dose response. Product A was also safe for the potato crop.

[00134] Efficacy against plant pathogenic Fusarium species in vitro

[00135] Efficacy of Product A was tested in vitro against four plant pathogenic Fusarium isolates. Isolates were 1. F. graminearum ( Fusarium head blight, Fusarium crown and root rot on cereals), 2. F. oxysporum (basal root rot of onion) and two strains of F. oxysporum f. sp. cubense race 4 (Panama disease / Fusarium wilt of banana).

[00136] Fungal isolates were cultivated on potato dextrose agar for 7 days in dark at room temperature before the trial. Treatments were as follows: 1. Untreated control (UTC); 2. 1% Product A, 3. 2% Product A; 4. 3% Product A.

[00137] The trial was conducted in 6 replicates. Product A was added to potato dextrose agar medium and pH was set to 9.45 by adding 1 M HC1 or 1M NaOH. Medium was autoclaved and poured to 85 mm petri dishes one day before the trial. Fungal isolates were transferred to growth media (potato dextrose agar) amended with Product A and incubated at dark in room temperature. Fungal colony diameter was measured 3, 7 and 10 days after inoculation.

[00138] Results

[00139] In this trial mycelium growth was markedly inhibited by Product A amendment in culture media in all fungal isolates tested (Figure 8). After 3 -days’ incubation, in all fungal isolates, the difference in the colony diameter between UTC and 2 and 3% treatments was statistically significant. After 7 days, also the difference between UTC and 1% treatment was statistically significant.

[00140] Average growth rate (increase in fungal colony radius per day) was calculated after 3 days’ incubation. On 0, 1, 2 and 3% plates the average growth rate was 7.3, 0.7, 0.2 and 0.03 mm/day for F. graminearum 5.1, 1.2, 0.7 and 0.2 mm/day for F. oxysporum 4.5, 1, 0.5 and 0.1 mm/day for F. oxysporum f. sp. cubense A; and 4.5, 1.2, 0.7 and 0.2 mm/day for F. oxysporum f. sp. cubense B (Figure 9). Growth rate was quite similar between different species.

[00141] To conclude, Product A amendment in culture media inhibited mycelium growth significantly in all concentrations tested compared to untreated control in all fungal isolates.

[00142] While the forgoing examples are illustrative of the principles of the present invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts of the invention. Accordingly, it is not intended that the invention be limited, except as by the claims set forth below.

[00143] The verbs “to comprise” and “to include” are used in this document as open limitations that neither exclude nor require the existence of also un-recited features. The features recited in depending claims are mutually freely combinable unless otherwise explicitly stated. Furthermore, it is to be understood that the use of "a" or "an", that is, a singular form, throughout this document does not exclude a plurality.

[00144] The following embodiments are characteristic of the present application:

1. Use of a composition, which comprises rosin as antipathogenic agent, at least one solvent, and at least one auxiliary agent for treatment of plant pathogens. 2. Use according to claim 1 for treatment of plant pathogens, wherein the plant pathogens are selected from fungi, particularly fungi selected from the group consisting of Fusarium sp, Ustilago sp, Pyrenophora sp, Phytophthora sp, Botrytis sp, Bipolaris sp, Stagonospora sp, Drechslera sp, Magnaporthe sp and Aspergillus sp.

3. Use according to claim 1 or 2 for treatment of plant pathogens on plants or on parts of plants, such as foliage, fruit, tubers, bulbs, seeds, stolons and rhizomes.

4. Use according to any one of the preceding claims for treatment of plants or parts of plants before planting, during growth, after harvesting, or in any combinations thereof.

5. Use according to any one of the preceding claims, wherein the amount of rosin is 0.1- 25%, preferably 0.1-20%, more preferably 0.5-20%, still more preferably 0.5-10% or 1-5%, by weight of the total weight of the composition.

6. Use according to any one of the preceding claims, wherein the rosin is in the form of free rosin acid or in the form of its alkali metal, pyridine, triethanolamine, ammonium or amine salt or as a mixture of free rosin acid and its salt, preferably rosin is in the form of its alkali metal salt.

7. Use according to any one of the preceding claims, wherein the solvent is selected from the group consisting of alcohols, dimethylsulfoxide, water and mixtures thereof, preferably from ethanol, isopropanol, propylene glycol, glycerol, dimethylsulfoxide, and mixtures thereof.

8. Use according to any one of the preceding claims, wherein the solvent is at least one alcohol, which is used at a concentration of 5-70% by weight of the total weight of the composition.

9. Use according to any one of the preceding claims, wherein the at least one auxiliary agent is selected from the group consisting of surface active agents, viscosity modifying agents, adsorption modifying agents and fixing agents. 10. Use according to any one of the preceding claims, wherein the plants are selected from the group consisting of cereals, fruit and fruit trees, berries, vegetables and other cultivated plants, preferably from the group consisting of wheat, barley, rye, oats, rice, com, spelt, sorghum; apple, plum, pear, peach, citrus, orange, mandarin orange, lime, grapefruit, grape, banana, cooking banana, pineapple, mango; cucumber, watermelon, melon, tomato, carrot, beetroot, turnip, rutabaga (yellow turnip), spinach, celery, red pepper, eggplant, garlic, onions, leek, cabbages, lettuce, beans (e.g. broad bean, faba bean), peas, dill, parsley, potato; strawberry, raspberry, highbush blueberry, blackcurrant, redcurrant, whitecurrant, gooseberry; olives, field com, reed canary grass, sweet potato, sugar cane, sugar beet, yam, cassava, soybean, peanut, turnip rape, sunflower, linseed, rapeseed, tobacco, tea, cocoa, coffee, cultivated grass (Poaceae) and legume.

11. Use according to claim 10, wherein the plants are selected from potato, sweet potato, banana, cooking banana, coffee, wheat, barley, rye, oats, rice, com, apple, beans, olives, cocoa, soybean, onions and grape.

12. Use according to any one of the preceding claims, wherein the composition consists of rosin as antifungal agent, at least one solvent and at least one auxiliary agent.

13. The use according to claim 11, wherein the composition consists essentially of 0.1- 20% (w/w) of rosin, 70-99% (w/w) of at least one solvent and 0.1-10% of at least one auxiliary agent.

14. Use according to any one of the preceding claims for treatment of late blight of potato, wherein the concentration of rosin in the composition is 0.1-20 wt-%, preferably 0.5-10 wt- %, of the total weight of the composition.

15. Use according to any one of claims 1 to 13 for antifungal treatment of potato tubers before planting, wherein the composition is applied in an amount which provides 1-20 g rosin / kg potato tubers.

16. Use according to any one of claims 1 to 13 for antifungal treatment of nuts and cereal crops, particularly after harvesting to prevent growth of Aspergillus sp, more particularly Aspergillus flavus and Aspergillus parasiticus. 17. Use according to any one of the preceding claims, wherein the treatment comprises repeated use of the composition as often as required, preferably at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 times.

18. A method for antifungal treatment of plants, wherein the method comprises the steps of

- providing a composition of rosin as antifungal agent, at least one solvent and at least one auxiliary agent;

- applying the composition on the plants or parts of plants wherein the composition comprises an amount of rosin, which is 0.1-25% by weight of the total weight of the composition.

19. An antifungal composition, which consists essentially of rosin as an antifungal agent, at least one solvent and at least one auxiliary agent, wherein the amount of rosin is 0.1-25% by weight of the total weight of the composition.

INDUSTRIAL APPLICABILITY

[00145] At least some embodiments of the present invention find industrial application in agriculture and agricultural chemistry.

CITATION LIST

Patent Literature CN 102217621 KR 100346313 US 5728740 A

WO 2016/116668 A1