Methods for treating potato wart disease

Abstract

Provided are methods of treating potato wart disease with a stabilized aqueous hydrogen peroxide composition that includes a sugar alcohol as stabilizer and active ingredient, and that does not contain silver, organophosphonate, peroxyacetic acid or other peracid, or stannate. The composition optionally includes a carboxylic acid. Administering the stabilized aqueous hydrogen peroxide composition containing a sugar alcohol as stabilizer and active ingredient to the potato plant can induce stress response mechanisms and modulate plant defense and immune responses in the treated plants. It was found that potato plants exhibit no wart formation when the soil in which they were grown, which contained Synchytrium endobioticum spores, was treated with a stabilized aqueous hydrogen peroxide composition including a sugar alcohol as stabilizer and active ingredient as described herein.

Description

[0001] INVENTION TITLE: METHODS FOR TREATING POTATO WART DISEASE TECHNICAL FIELD

[0002] The present invention relates to methods of treating potato wart disease with a stabilized aqueous hydrogen peroxide composition comprising a sugar alcohol as stabilizer and active ingredient, and that does not contain silver, organophosphonate, peroxyacetic acid or other peracid, or stannate. The composition optionally includes a carboxylic acid. Administering the stabilized aqueous hydrogen peroxide composition comprising a sugar alcohol as stabilizer and active ingredient to the potato plant can induce stress response mechanisms and modulate plant defense and immune responses in treated plants. It was found that potato plants exhibit no wart formation when the soil in which they were grown, which contained Synchytrium endobioticum spores, was treated with a stabilized aqueous hydrogen peroxide composition comprising a sugar alcohol as stabilizer and active ingredient as described herein.

[0003] BACKGROUND ART

[0004] The background description provided herein is for the purpose of generally presenting context of the disclosure. Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art, or suggestions of the prior art, by inclusion in this section.

[0005] Potato wart disease is caused by infection of the cultivated potato plant (Solaium tuberosum L.) by Synchytrium endobioticum, which is an intracellular obligate biotrophic chytrid fungus, resulting in the formation of warts or cauliflower-like malformations or galls of affected tissue (van de Vossenberg et al., PhytoFrontiers™ 2024, 4(1):31-39). It is also known by various other names, including potato tumor, black wart, and cauliflower disease (Obidiegwu et al., Theor Appl Genet 127(4): 763-780 (2014)). The galls can vary in size from the size of a pea to several centimeters in diameter. Potato wart does not kill its host plant, as this soil-borne fungal pathogen requires the host to reproduce. The spores of Synchytrium endobioticum can remain viable in soil and infectious for decades without a plant host (Potato Wart, Plant Pests and Diseases, USDA Animal and Plant Health Inspection Service, last modified May 28, 2024). Synchytrium endobioticum is considered by many countries as a quarantine pest, and in some countries, when a field is verified to have been infected with S. endobioticum, potato production of non-resistant potato cultivars can be forbidden in the site until the absence of S. endobioticum sporangia is demonstrated, which can take decades (Obidiegwu et al., Theor Appl Genet 127(4): 763-780 (2014)). Previous chemical controlmethods were found to be ineffective in eliminating S. endobioticum from the soil, and some chemical treatments were found to leave the treated soil sterile or to be phytotoxic (Ibid ). Most of the previous chemical control methods were deemed to be unreliable or toxic to the plant or environment. Thus, there currently are few options for managing potato wart disease other than field quarantines of contaminated plots for years, or cultivation of wart-resistant varieties.

[0006] Therefore, there is a need to develop effective methods for treating potato wart disease, where the method uses compositions that are efficacious, environmentally friendly, non-phytotoxic, and cost-effective.

[0007] SUMMARY OF THE INVENTION

[0008] The present disclosure has been made to solve the above-mentioned problems and other technical problems that have yet to be resolved.

[0009] Provided are compositions and methods of using a composition containing hydrogen peroxide and a sugar alcohol as a stabilizer and active ingredient for the treatment of potato wart disease. The composition optionally contains a carboxylic acid. The composition contains no silver, organophosphonate, peroxyacetic acid, or stannate. Exemplary embodiments of the composition have been tested and found to be effective in stimulating the plant’s response to Synchytrium endobioticum infection, and treatment of compost infected with Synchytrium endobioticum resulted in the prevention of wart or gall formation in the potato plant.

[0010] Provided are methods of suppressing wart formation in potatoes caused by Synchytrium endobioticum. The methods include treating water with a stabilized hydrogen peroxide composition provided herein to produce a treated water, wherein the stabilized peroxide composition comprises water, hydrogen peroxide, and a sugar alcohol, wherein the sugar alcohol is selected from the group consisting of sorbitol, xylitol, mannitol, lactitol, maltitol, erythritol, isomalt, and combinations thereof, and the stabilized peroxide composition contains no silver, organophosphonate, peroxyacetic acid, peracid, or stannate; treating seed potatoes with the treated water prior to planting; and administering the treated water via irrigation after planting for a time period in a range of from 60 days to 140 days. The treated water can be administered from after planting until harvest. The irrigation can deliver the treated water to roots. The administering of the treated water can be via a drip feed irrigation or micro-irrigation system. The administering of the treated water can be via a spray irrigation or sprinkler irrigation system. The administering of the treated water can be via a subirrigation system. Inthe methods, the treated water can contain a concentration of the stabilized hydrogen peroxide composition of from about 0.005 wt% to 5 wt% based on the weight of the treated water.

[0011] Also provided are methods of inhibiting or preventing fungal spore germination of Synchytrium endobioticum in soil or on a surface of a potato plant. The methods include detecting a presence of Synchytrium endobioticum in the soil to identify an infected soil; treating water with a stabilized hydrogen peroxide composition to produce a treated water, wherein the stabilized peroxide composition comprises water, hydrogen peroxide, and a sugar alcohol, wherein the sugar alcohol is selected from the group consisting of sorbitol, xylitol, mannitol, lactitol, maltitol, erythritol, isomalt, and combinations thereof, and the stabilized peroxide composition contains no silver, organophosphonate, peroxyacetic acid, peracid, or stannate; and administering the treated water to the infected soil.

[0012] The surface of the potato plant can be an underground surface or an above-ground surface. The surface can be a surface of a tubers, a stolon, a stem, or any combination thereof. The detecting can be done via any method known in the art. For example, the detecting can be done by: a) direct microscopic examination of the soil for sporangia from Synchytrium endobioticum,' or b) a molecular testing method to detect the presence of Synchytrium endobioticum DNA in the soil; or c) a combination of a) and b). The molecular testing method can be a PCR-based detection method. In the methods, the treated water can contain a concentration of the stabilized hydrogen peroxide composition of from about 0.1 wt% to 5 wt% based on the weight of the treated water. In the methods, the method can further include removing plants from in and around the infected soil; providing a temporary watertight dam around the infested area to enclose the infested area and produce a dammed area; filling the dammed area with the treated water to a level that an upper surface of the soil in the dammed area is continuously submerged under the treated water; and maintaining the dammed area filled with the treated water for a period of at least 5 weeks. In the methods, a height of the temporary watertight dam above the upper surface of the soil in the dammed area can be 10 cm to 100 cm, measured from the upper surface of the soil to the highest point of the temporary watertight dam above the upper surface of the soil. The temporary watertight dam can include a high-density polyethylene, a polyethylene terephthalate resin, a polycarbonate resin, a reinforced polyethylene resin, a reinforced polypropylene resin, an ethylene propylene diene monomer resin, a polyvinyl chloride resin, or a combination thereof.

[0013] Also provided are methods of increasing potato resistance to wart formation caused by Synchytrium endobioticum. The method includes treating water with a stabilized hydrogenperoxide composition provided herein to produce a treated water, wherein the stabilized peroxide composition comprises water, hydrogen peroxide, and a sugar alcohol, wherein the sugar alcohol is selected from the group consisting of sorbitol, xylitol, mannitol, lactitol, maltitol, erythritol, isomalt, and combinations thereof, and the stabilized peroxide composition contains no silver, organophosphonate, peroxyacetic acid, peracid, or stannate; administering the treated water via irrigation to soil for a time period in a range of from 1 day to 14 days prior to planting; treating seed potatoes with the treated water prior to planting for a period of 1 hour to 36 hours prior to planting; and administering the treated water via irrigation after planting for a time period in a range of from 60 days to 140 days. The treated water can be administered from after planting until harvest. In the methods, the irrigation can deliver the treated water to roots. Administering the treated water can be via: a) a drip feed irrigation or micro-irrigation system; or b) a spray irrigation or sprinkler irrigation system; or c) a subirrigation system; or d) any combination of a) to c). The treated water can contain a concentration of the stabilized hydrogen peroxide composition of from about 0.03 wt% to 3 wt% based on the weight of the treated water. The stabilized hydrogen peroxide composition can include the hydrogen peroxide in an amount from about 5 wt% to 50 wt% based on the total weight of the composition; and the sugar alcohol in an amount form about 0.5 wt% to 15 wt% based on the total weight of the composition. In the stabilized hydrogen peroxide composition, a weight ratio of the hydrogen peroxide to the sugar alcohol can be from about 4:1 to 100:1. In the methods, the stabilized hydrogen peroxide composition can further include a carboxylic acid selected from the group consisting of formic acid, acetic acid, citric acid, lactic acid, glycolic acid, malic acid, oxalic acid, propionic acid, benzoic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, tartaric acid, salicylic acid, and combinations thereof. The carboxylic acid can be present in an amount from about 0.1 wt% to 10 wt% based on the total weight of the composition. In the stabilized hydrogen peroxide composition, a weight ratio of the hydrogen peroxide to the carboxylic acid in the stabilized hydrogen peroxide composition can be from about 1.5:1 to 60:1.

[0014] Also provided are methods of treating a potato plant infected with Synchytrium endobioticum. The methods including detecting Synchytrium endobioticum in the potato plant; and administering a stabilized hydrogen peroxide composition provided herein to the plant. The administering of the treated water to the infected plant can begin at the first symptom of infection. The administering of the treated water to the infected plant can continue until symptoms of infection disappear. The administering of the treated water to the infected plantcan continue until harvest. Administering the treated water can be performed via a drip feed irrigation or micro-irrigation system; or via a spray irrigation or sprinkler irrigation system, or via a subirrigation system, or any combination thereof.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings illustrate a preferred embodiment of the present disclosure and together with the foregoing disclosure, serve to provide further understanding of the technical features of the present disclosure, and thus, the present disclosure is not construed as being limited to the drawing. The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0017] FIG. 1 is a bar graph showing the incidence of wart formation on potato eyepiece segments inoculated with a negative control (neg) compost sample, a positive control (pos) compost sample, and a sample of compost containing resting spores of Synchytrium endobioticum treated with a composition containing hydrogen peroxide and a sugar alcohol as stabilizer and active ingredient as described herein (per).

[0018] DETAILED DESCRIPTION

[0019] Hereinafter, the present disclosure will be described in more detail for a better understanding of the invention.

[0020] The headings used herein are for organizational purposes only and are not meant to limit the scope of the description or the claims in any way.

[0021] While the present disclosure is open to various modifications and alternative embodiments, specific embodiments thereof will be described and illustrated by way of example in the accompanying drawings. However, this is not purported to limit the present disclosure to a specific disclosed form, but it shall be understood to include all modifications, equivalents and substitutes within the idea and the technological scope of the present disclosure.

[0022] I. DEFINITIONS

[0023] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which the inventions belong.

[0024] All patents, patent applications, published applications and publications, websites and other published materials referred to throughout the entire disclosure herein, unless noted otherwise, are incorporated by reference in their entirety. Where reference is made to a URL or other such identifier or address, it is understood that such identifiers can change andparticular information on the internet can come and go, but equivalent information can be found by searching the internet. Reference thereto evidences the availability and public dissemination of such information.

[0025] In the event that there are a plurality of definitions for terms herein, those in this section prevail.

[0026] As used here, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise.

[0027] As used herein, unless specifically indicated otherwise, the word "or" is used in the "inclusive" sense of "and / or" and not the "exclusive" sense of "either / or."

[0028] As used herein, the term “exemplary” means “serving as an example or illustration,” and should not be construed as being preferred or advantageous over other configurations disclosed herein.

[0029] As used herein, all ranges include the upper and lower limits. As used herein, the recitation of a numerical range for a variable is intended to convey that the variable can be equal to any value(s) within that range, as well as any and all sub -ranges encompassed by the broader range. Thus, the variable can be equal to any number value or values within the numerical range, including the endpoints of the range. As an example, a variable which is described as having a value from 0 to 10, can be 0, 4, 2 to 6, 2.75, 3.3 to 4.4, etc.

[0030] As used herein, “about” is a term of approximation and is intended to include minor variations in the literally stated amounts, as would be understood by those skilled in the art. Such variations include, for example, standard deviations associated with techniques commonly used to measure the amounts of the constituent elements or components of composition, or other properties and characteristics, or within typical experimental error for the application or purpose intended. For example, an acceptable margin of error can be in the range of 3% and 7%. All of the values characterized by the above-described modifier "about," are also intended to include the exact numerical values associated therewith. Hence “about 10 percent” means “about 10 percent” and also “10 percent.”

[0031] As used herein, “optional” or “optionally” means that the subsequently described element, event or circumstance does or does not occur, and that the description includes instances where the element, event or circumstance occurs and instances where it does not. For example, an optional component in a formulation means that the component may be present or may not be present in the formulation.In the examples, and throughout this disclosure, all parts and percentages are by weight (wt%) and all temperatures are in °C, unless otherwise indicated.

[0032] As used herein, the phrase “based on the weight of the composition” with reference to % refers to wt% (mass% or (w / w)%).

[0033] As used herein, the terms “comprises” and “comprising” are inclusive and open ended, and not exclusive. When used in the specification and claims, the terms “comprises” and “comprising” and variations thereof, such as “including” or “having” mean the specified features, steps or components are included, but do not exclude other features, steps or components. In this application, it should be understood that terms such as “comprising”, “including” or “having” are intended to indicate that there is a feature, number, step, operation, component, part, or a combination thereof described in the specification, and they do not exclude in advance the possibility of the presence or addition of one or more other features or numbers, steps, operations, components, parts or combinations thereof.

[0034] Any compositions described herein are intended to encompass compositions which consist of, consist essentially of, as well as comprise, the various constituents identified herein, unless explicitly indicated to the contrary.

[0035] Unless indicated otherwise, each of the individual features or embodiments of the present specification are combinable with any other individual feature or embodiment that are described herein, without limitation. Such combinations are specifically contemplated as being within the scope of the present invention, regardless of whether they are explicitly described as a combination herein.

[0036] As used herein, a “combination” refers to any association between or among two or more items. The combination can be two or more separate items, such as two compositions or two collections, a mixture thereof, such as a single mixture of the two or more items, or any variation thereof. The elements of a combination are generally functionally associated or related.

[0037] As used herein, “potato wart disease” refers to the infection of the cultivated potato plant (Solarium tuberosum L.) caused by Synchytrium endobioticum.

[0038] As used herein, the “stabilized hydrogen peroxide composition” refers to the compositions described herein that include hydrogen peroxide and a sugar alcohol as stabilizer and active ingredient, where the composition does not include silver, organophosphonate, peroxyacetic acid, or stannate.

[0039] Hereinafter, the present disclosure will be described in detail.II. Stabilized Hydrogen Peroxide Compositions for Treating Potato Wart Disease The methods provided herein include the delivery of a composition that includes hydrogen peroxide and a sugar alcohol as stabilizer and active ingredient to a field in which the presence of Synchytrium endobioticum is detected, or to a plant infected with Synchytrium endobioliciim. or a combination thereof. The stabilized hydrogen peroxide composition used in the methods provided herein does not include silver, organophosphonate, peroxyacetic acid, or stannate. The sugar alcohol can be selected from the group consisting of sorbitol, xylitol, mannitol, lactitol, maltitol, erythritol, isomalt, and combinations thereof. In some compositions, the sugar alcohol comprises sorbitol, alone or in combination with one or more of xylitol, mannitol, lactitol, maltitol, erythritol, and isomalt. In some compositions, the sugar alcohol comprises xylitol, alone or in combination with one or more of sorbitol, mannitol, lactitol, maltitol, erythritol, and isomalt. In some compositions, the sugar alcohol comprises lactitol, alone or in combination with one or more of sorbitol, xylitol, mannitol, maltitol, erythritol, and isomalt. In some compositions, the sugar alcohol comprises maltitol, alone or in combination with one or more of sorbitol, xylitol, mannitol, lactitol, erythritol, and isomalt. In some compositions, the sugar alcohol comprises erythritol, alone or in combination with one or more of sorbitol, xylitol, mannitol, lactitol, maltitol, and isomalt. In some compositions, the sugar alcohol comprises isomalt, alone or in combination with one or more of sorbitol, xylitol, mannitol, lactitol, maltitol, and erythritol.

[0040] The stabilized hydrogen peroxide composition utilized in the methods provided herein include water. The hydrogen peroxide can be present in an amount from about 5 wt% to 50 wt% based on the total weight of the composition. The amount of hydrogen peroxide can be in a range of 7.5 wt% to 45 wt%, or 10 wt% to 40 wt%, or 15 wt% to 35 wt%, or 5 wt% to 30 wt%, or 15 wt% to 50 wt%, or 35 wt% to 50 wt%, or 40 wt% to 50 wt%. In some compositions, the amount of hydrogen peroxide is 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 41 wt%, 42 wt%, 43 wt%, 44 wt%, 45 wt%, 46 wt%, 47 wt%, 48 wt%, 49 wt%, or 50 wt%. In some embodiments, the composition contains at least 15 wt% hydrogen peroxide. In some embodiments, the composition contains at least 30 wt% hydrogen peroxide. In some embodiments, the composition contains at least 40 wt% hydrogen peroxide. In some embodiments, the composition contains at least 42 wt% hydrogen peroxide.

[0041] The sugar alcohol can be present in an amount form about 0.5 wt% to 15 wt% based on the total weight of the composition. The amount of sugar alcohol can be in a range of 0.75 wt% to 12.5 wt%, or 1 wt% to 10 wt%, or 1.5 wt% to 7.5 wt%, or 2.5 wt% to 10 wt%, or 5 wt%to 10 wt%. In some compositions, the amount of sugar alcohol is 0.5 wt%, 0.75 wt%, 1 wt%, 1.25 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5 wt%, 5.5 wt%, 6 wt%, 6.5 wt%,7 wt%, 7.5 wt%, 8 wt%, 8.5 wt%, 9 wt%, 9.5 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, or 15 wt%. In some embodiments, the stabilized hydrogen peroxide composition utilized in the methods provided herein contains at least 1 wt% sugar alcohol. In some embodiments, the composition contains at least 2.5 wt% sugar alcohol. In some embodiments, the composition contains at least 3.5 wt% sugar alcohol. In some embodiments, the composition contains the sugar alcohol in an amount from about 7.0 to 8.0 wt%.

[0042] The weight ratio of hydrogen peroxide to sugar alcohol in the stabilized hydrogen peroxide composition can be from 4:1 to 100:1, and can be from 5:1 to 75:1, or from 6:1 to 50:1, or from 7:1 to 10:1.

[0043] The stabilized hydrogen peroxide composition utilized in the methods provided herein can include a carboxylic acid. The carboxylic acid can be selected from the group consisting of formic acid, acetic acid, citric acid, lactic acid, glycolic acid, malic acid, oxalic acid, propionic acid, benzoic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, tartaric acid, and combinations thereof. When present in the stabilized hydrogen peroxide composition, the carboxylic acid can be present in an amount from about 0.1 wt% to 10 wt%. The amount of carboxylic acid can be from about 0. 5 wt% to 7.5 wt%, or 0.75 wt% to 5 wt%, or 1.0 to 3.5 wt%. In some compositions, the amount of carboxylic acid, when present, is 0.1 wt%, 0.25 wt%, 0.5 wt%, 0.75 wt%, 1 wt%, 1.25 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5.0 wt%, 5.5 wt%, 6 wt%, 6.5 wt%, 7 wt%, 7.5 wt%, 8 wt%, 8.5 wt%, 9 wt%, 9.5 wt%, or 10 wt%. In some embodiments, the composition contains at least 1 wt% carboxylic acid. In some embodiments, the composition contains at least 1.5 wt% carboxylic acid. In some embodiments, the composition contains at least 3 wt% carboxylic acid.

[0044] The carboxylic acid, when present, can be in a weight ratio of hydrogen peroxide to the carboxylic acid of from 1.5:1 to 60:1, or from 2:1 to 50:1, or from 3:1 to 30:1, or from 5:1 to 20: 1. In the methods provided herein, when the stabilized hydrogen peroxide composition is diluted with water and administered to a plant, the carboxylic acid, when taken up by the plant, can modify the osmotic pressure within the vasculature, and can modulate flow of water through the vasculature. For example, inclusion of citric acid in the formulation can result in opening up of the xylem vessels when the composition is provided to the plant.Some formulations of the stabilized hydrogen peroxide composition utilized in the methods provided herein have been found to be stable, before dilution, for at least 100 days under ambient storage conditions (20°C to 30°C), where “stable” means that at least 90% of the initial wt% hydrogen peroxide in the composition is still present in the composition after the indicated testing period. In some tests, the amount of hydrogen peroxide remaining in the composition after 100 days is 95% or higher.

[0045] The stabilized hydrogen peroxide composition utilized in the methods provided herein, can be prepared by mixing the sugar alcohol and hydrogen peroxide, and if present the carboxylic acid, and water if needed to achieve the desired concentration, together in a stainless steel, glass, or non-reactive plastic vessel. Mixing can be achieved using a paddle or blade mixer, attached to a motor to rotate the paddle or blade mixer within the vessel to mix the components together. The rotational speed of the paddle or blade mixer can be from about 100 rpm to 1000 rpm, depending on the size of the vessel and the volume of the materials to be mixed together within the vessel. The mixing can be done at ambient temperature, such as a temperature in the range of 20°C-30°C. The mixing vessel can be configured to provide cooling during mixing. The mixing vessel can be cooled during mixing to maintain a temperature of the mixture within the vessel at a temperature in the range of 5°C to 25°C. The mixing vessel can be cylindrical in shape, typically having an inside height that is larger than the inside diameter of the vessel. For example, the ratio of the inside height to the inside diameter can be in a range of 1.5 : 1 to 2.5 : 1.

[0046] The sugar alcohol has the effect of not only stabilizing the hydrogen peroxide, but when the stabilized hydrogen peroxide composition is diluted and provided to the plant, the sugar alcohol can help to stimulate the plant’s defense mechanisms. Providing a sugar alcohol, such as sorbitol, has been found to improve a plant’s ability to deal with stress, and it is believed that the sugar alcohol can induce stress response mechanisms and modulate plant defense and immune responses in treated plants. Accordingly, the sugar alcohol plays a dual role as a stabilizer of the composition as well as an active ingredient that when provided to a plant can stimulate stress response mechanisms and modulate plant defense and immune responses against pathogen and parasite attack.

[0047] III. Methods of Treating Potato Wart Disease

[0048] Provided herein are methods of treating potato wart disease. The methods include preparing an aqueous solution of a stabilized hydrogen peroxide composition that includes a sugar alcohol, where the composition utilized for the treatment is environmentally friendly, andeffective. The methods can include treating a field in which Synchytrium endobioticum is detected, or in which Synchytrium endobioticum spores are detected. The methods can include treating a plant infected with Synchytrium endobioticum. The methods can include treating an infected field with a stabilized hydrogen peroxide composition that includes a sugar alcohol described herein prior to planting, and irrigation of the potato plants with the stabilized hydrogen peroxide composition.

[0049] Synchytrium endobioticum is the causal agent of potato wart disease. Infection typically induces formation of wart-like growths or galls when a susceptible potato cultivar is infected. Solanum tuberosum is the only commercial crop that is attacked by potato wart. Tubers, stolons, and stems can all become infected when the fungus is present in the soil. The surface of the wart has an undulating for that resemble the head of a cauliflower. The warts or galls initially on underground plant parts may have the same color as potato skin or can be white, and can become green upon exposure to light. With age or decaying, the warts can turn black. Because Synchytrium endobioticum does not kill its host plant, and some infections cause minimal noticeable negative impacts on vegetative growth or only sometime results in reduced plant vigor, below ground infections may not be evident until harvest.

[0050] Confirmation of the presence of Synchytrium endobioticum in the soil can be confirmed using any method known in the art. For example, soil samples can be subjected to direct microscopic examination for sporangia. These methods typically include isolating potato wart spores and using a microscope to evaluate the visual appearance of the spores. Soil samples also can be tested for infestation using a bioassay. Any bioassay known in the art can be used (e.g., see van de Vossenberg, Phytopathology 109:1043-1051 (2019). The presence of absence of Synchytrium endobioticum DNA in a soli sample also can be used to confirm the presence of Synchytrium endobioticum in the soil. For example, Synchytrium endobioticum DNA can be confirmed using a molecular testing method. Molecular testing methods include PCR-based detection methods. PCR-based detection methods are known in the art (see van den Boogert, European Journal of Plant Pathology 113: 47-57 (2005); van Gent-Pelzer, Eur J Pathol 126: 129-133 (2010); and van de Vossenberg etal., PhytoFrontiers™ 2024, 4(1):31 -39).

[0051] It has been found that administering the stabilized hydrogen peroxide composition provided herein to potato plants can result in the prevention of wart or gall formation. Without wishing to be bound by theory, it is believed that the hydrogen peroxide and the sugar alcohol in the diluted stabilized hydrogen peroxide composition provided herein can stimulate the plant’s defense mechanisms, and have a further positive effect on plant resistance to subsequentinfection as well as accelerating plant recovery. The stimulated plant resistance is evidenced by the prevention of wart formation in potatoes planted in infected medium, as described in Example 91.

[0052] In one embodiment, provided is a method that includes treating an irrigation water with the stabilized hydrogen peroxide composition provided herein. The stabilized hydrogen peroxide composition typically is diluted for use in irrigation. The stabilized hydrogen peroxide composition can be diluted so that the amount of composition in the irrigation water is from about 0.005 wt% to 5 wt% based on the weight of the irrigation water. The stabilized hydrogen peroxide composition can be diluted so that the amount of composition in the irrigation water is from about 0.001 wt% to 4 wt%, or 0.01 wt% to 3 wt%, or 0.05 wt% to 2.5 wt%, or 0.075 wt% to 2 wt%, or 0.1 wt% to 1.5 wt%, based on the weight of the irrigation water.

[0053] The stabilized hydrogen peroxide composition can be diluted in clean water to produce a treated water containing a concentration of the stabilized hydrogen peroxide composition of from about 0.005 wt% to 5 wt% based on the weight of the treated water. For example, one part by weight stabilized hydrogen peroxide composition can be added to 99 parts by weight clear water to produce a treated water containing 1 wt% stabilized hydrogen peroxide composition. The amount of stabilized hydrogen peroxide composition in the treated water can be 0.005 wt%, 0.01 wt%, 0.02 wt%, 0.03 wt%, 0.04 wt%, 0.05 wt%, 0.06 wt%, 0.07 wt%, 0.08 wt%, 0.09 wt%, 0.1 wt%, 0.15 wt%, 0.2 wt%, 0.25 wt%, 0.3 wt%, 0.35 wt%, 0.4 wt%, 0.45 wt%, 0.5 wt%, 0.55 wt%, 0.6 wt%, 0.65 wt%, 0.7 wt%, 0.75 wt%, 0.8 wt%, 0.85 wt%, 0.9 wt%, 0.95 wt%, 1 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, 1.4 wt%, 1.5 wt%, 1.6 wt%, 1.7 wt%, 1.8 wt%, 1.9 wt%, 2.0 wt%, 2.1 wt%, 2.2 wt%, 2.3 wt%, 2.4 wt%, 2.5 wt%, 2.6 wt%, 2.7 wt%, 2.8 wt%, 2.9 wt%, 3.0 wt%, 3.1 wt%, 3.2 wt%, 3.3 wt%, 3.4 wt%, 3.5 wt%, 3.6 wt%, 3.7 wt%, 3.8 wt%, 3.9 wt%, 4.0 wt%, 4.1 wt%, 4.2 wt%, 4.3 wt%, 4.4 wt%, 4.5 wt%, 4.6 wt%, 4.7 wt%, 4.8 wt%, 4.9 wt%, or 5.0 wt%.

[0054] The dilution can be performed in bulk, such as to prepare 1000 L or 2000 L batches of water for irrigation. The dilution can be accomplished by metering in an amount of the stabilized hydrogen peroxide composition to produce the targeted dilution in the irrigation water directly in the irrigation pipes. Such metering devices are known in the art. Both a dilution to produce a diluted stabilized hydrogen peroxide composition and a metering device to introduce the diluted composition into the irrigation water directly in the irrigation pipes can be used.The treated irrigation water containing the diluted stabilized hydrogen peroxide composition provided herein can be provided to the plant via any irrigation method. The treated water can be delivered using a drip feed irrigation or micro-irrigation system. The treated water can be delivered using a spray irrigation or sprinkler irrigation system. The treated water can be delivered using a subirrigation system (delivering the water below the ground surface).

[0055] The irrigation with the water that includes the diluted stabilized hydrogen peroxide composition provided herein can continue until all symptoms of the disease disappear. Irrigation with the water that includes the diluted stabilized hydrogen peroxide composition provided herein can continue until harvest. Irrigation with the water that includes the diluted stabilized hydrogen peroxide composition provided herein can continue indefinitely and can be used as the sole source of irrigation water. By continuously using irrigation water that includes the diluted stabilized hydrogen peroxide composition provided herein during normal water cycles, reinfection can be minimized or prevented. By continuously using irrigation water that includes the diluted stabilized hydrogen peroxide composition provided herein during normal water cycles, it is possible that increased crop production can be realized. Thus, the diluted stabilized hydrogen peroxide composition provided herein can minimize or reverse the effects of the Synchytrium endobioticum infection. Continuously using irrigation water that includes the diluted stabilized hydrogen peroxide composition provided herein during normal water cycles may prevent reinfection and minimize or eliminate the source of the infection in the treated area.

[0056] The treatment can include periodic treatments over extended periods of time instead of continuous treatment with the treated water. For example, the treatment can be administered once a day, or every other day, or once a week, or every other week, or once a month, or every other month, or some combination thereof.

[0057] The method can include treating all equipment to be used with the infected plant with the stabilized hydrogen peroxide composition before contacting the plant, after contacting the plant, or both before and after contacting the plant. The stabilized hydrogen peroxide composition provided herein can be used without dilution for treating some equipment. The stabilized hydrogen peroxide composition provided herein can be diluted prior to treating the equipment.

[0058] The stabilized hydrogen peroxide composition when diluted in water for treating equipment can deliver an amount of H2O2 in the treated water for equipment cleaning that is about 0.2 wt% to 5 wt%. The stabilized hydrogen peroxide composition when diluted in waterfor treating equipment can deliver an amount of H2O2 in the treated water for equipment cleaning that is about 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, or 5 wt% based on the weight of the treated water to be applied to the leaves and / or fruit.

[0059] Because Synchytrium endobioticum infection can have a devastating effect on potato crops, and have been reported to be responsible for destruction of a significant amount of food crops annually, use of the stabilized hydrogen peroxide composition provided herein can dramatically improve food production by minimizing or eliminating crop loss.

[0060] IV. Methods of Treating Soil

[0061] Also provided are methods of treating soil to minimize or eliminate fungal spore germination in soil infected with Synchytrium endobioticum. In the methods, plots determined to have been subject to Synchytrium endobioticum infection are irrigated to saturation using a stabilized hydrogen peroxide composition provided herein to treat the spores in the soil. Irrigation to saturation includes providing an amount of a diluted stabilized hydrogen peroxide composition so that the level provided matches ground level during the irrigation process, and keeps the soil submerged beneath the diluted solution of the stabilized hydrogen peroxide composition. By providing an amount of diluted stabilized hydrogen peroxide composition to flood the infected area, the stabilized hydrogen peroxide composition can efficiently treat the spores in a shorter amount of time then when the diluted stabilized hydrogen peroxide composition is provided via standard irrigation. The treatment may result in minimized spore germination, or the inability of the spores to infect the potato plant.

[0062] In the methods provided herein, the land to be treated is first prepared for treatment. This can include removing plants from around and in the infected area to be treated. A temporary watertight dam is placed around this area. The temporary watertight dam typically is buried a few centimeters, such as 1 to 10 cm, below the surface of the soil. The temporary watertight dam typically has a surface above the soil surface that can be 10 cm to 100 cm above the soil surface, such as 10 cm, 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, or 100 cm above the ground, measured from the soil surface to the highest point of the watertight dam above the soil surface. The temporary watertight dam can be made of any material that is resistant to the passage of water and hydrogen peroxide through the material. Examples of the material include a plastic, such as high-density polyethylene, polyethylene terephthalate resin, a polycarbonate resin, a reinforced polyethylene resin, a reinforced polypropylene resin, anethylene propylene diene monomer resin, a polyvinyl chloride resin, and combinations thereof, but are not limited to these.

[0063] In the methods provided herein, the dammed area is filled with a dilute solution of the stabilized hydrogen peroxide composition provided herein. The concentration of the stabilized hydrogen peroxide composition used to treat the dammed area is in the range of about 0.1 wt% to 5 wt%. The range can be about 0.1 wt% to 2.5 wt%, 0.5 wt% to 2 wt%, or 0.75 wt% to 1.75 wt%, or 1 wt% to 1.5 wt%, or 0.25 wt% to 1.5 wt%. The concentration can be 0.25 wt%, 0.5 wt%, 0.75 wt%, 1 wt%, 1.25 wt%, 1.5 wt%, 1.75 wt%, 2 wt%, 2.25 wt%, 2.5 wt%, 2.75 wt%, 3 wt%, 3.25 wt%, 3.5 wt%, 3.75 wt%, 4 wt%, 4.25 wt%, 4.5 wt%, 4.75 wt%, or 5 wt%, with the balance being water.

[0064] During treatment, the dammed area is filled with the diluted solution of the stabilized hydrogen peroxide composition provided herein. The diluted solution of the stabilized hydrogen peroxide composition can be referred to as a treated water, as the stabilized hydrogen peroxide composition is added to a water to prepare the dilution, thereby treating the water to which the stabilized hydrogen peroxide composition is added. The diluted solution or treated water can be prepared as a bulk solution that is prepared and then pumped into the dammed area. The diluted solution can be prepared in situ using a dispenser that dispenses the appropriate amount of the stabilized hydrogen peroxide composition provided herein into a flow of water to prepare the desired concentration of the stabilized hydrogen peroxide composition. For example, the stabilized hydrogen peroxide composition provided herein can be inj ected into an eductor that uses the Venturi effect to pump the stabilized hydrogen peroxide composition provided herein into an enclosed eductor, mixing the stabilized hydrogen peroxide composition with the water flowing through the eductor to produce the diluted solution of the stabilized hydrogen peroxide composition, which is the treated water. Any method know in the art to mix two liquids together can be used to prepare the diluted solution of the stabilized hydrogen peroxide composition, and the method is not limited to using an eductor.

[0065] The dammed area is filled with the diluted solution of the stabilized hydrogen peroxide composition for a predetermined period of time. In some methods, the dammed area is maintained so that the soil surface is completely submerged under the diluted solution of the stabilized hydrogen peroxide composition for a period of at least 5 weeks, at least 6 weeks, at least 7 weeks, at least 8 weeks, at least 9 weeks, at least 10 weeks, at least 11 weeks, at least 12 weeks, at least 13 weeks, at least 14 weeks, or at least 15 weeks. The time can be a period from about 3 weeks to about 15 weeks. In some methods, the dammed area is maintained sothat the soil surface is maintained under the diluted solution of the stabilized hydrogen peroxide composition for a period of about 5 weeks to about 12 weeks, or a period from about 8 weeks to about 12 weeks. The diluted solution of the stabilized hydrogen peroxide composition is maintained within the dammed area so that the soil in the dammed area is continuously covered with the diluted solution of the stabilized hydrogen peroxide composition. The method can include using a sensor that monitors the level of the diluted solution of the stabilized hydrogen peroxide composition in the dammed area. The sensor can communicate with a pump or with valves or some combination thereof to automatically add additional diluted solution of the stabilized hydrogen peroxide composition when needed so that the soil is continuously submerged under the diluted solution of the stabilized hydrogen peroxide composition.

[0066] V. Examples

[0067] Hereinafter, preferred examples of the present disclosure, comparative examples compared thereto, and test examples for evaluating the examples are described. However, it will be apparent to those skilled in the art that these examples are merely illustrative of the present disclosure, and various changes and modifications may be made within the scope and technical spirit of the present disclosure, and it goes without saying that such variations and modifications fall within the scope of the appended claims.

[0068] Examples 1 to 90. Exemplary Formulations

[0069] Below are exemplary formulations of the stabilized hydrogen peroxide composition provided herein. The formulations are aqueous compositions, with water being the remainder of the composition. For example, in Example 1, the formulation contains 25 wt% hydrogen peroxide, 2.5 wt% sorbitol, and 72.5 wt% deionized water.

[0070]

[0071]

[0072]

[0073]

[0074] Each formulation can be prepared by mixing the sugar alcohol and the hydrogen peroxide, and if present the carboxylic acid, and water to achieve the desired concentration, together in a non-reactive vessel using a paddle mixer, attached to a motor to rotate the paddle mixer within the vessel to mix the components together. The mixing can be done at ambient temperature, such as a temperature in the range of 20°C-30°C.

[0075] Example 91. Plants Exposed to Treated Spores

[0076] Resting spores obtained from accessions in the NPPO-NL compost collection were prepared as inoculum. For the negative control samples, 30 gram of compost was mixed with 100 mL water in a 500 mL Gibco bottle (ThermoFisher Scientific, Carlsbad, CA) and maintained at 19°C for 2 hours, shaken every 15 minutes on a shaker table. Duplicate samples were prepared. Each of the mixed samples then were autoclaved for 30 minutes. After cooling, the contents of each bottle separately was filtered using a 20 micron nylon stocking and washed with 1 L of water, and the recovered solids in the stocking were pressed to remove excess water. The treated washed material from the stocking was collected and used as the negative control inoculant. For the positive control samples, 30 gram of compost was mixed with 100 mL water in a 500 mL Gibco bottle and maintained at 19°C for 2 hours, shaken every 15 minutes on ashaker table. Duplicate samples were prepared. The contents of each bottle was separately deposited into a 20 micron nylon stocking and washed with 1 L of water, and the recovered solids in the stocking were pressed to remove excess water. The recovered untreated washed material from the stocking was used as the positive control inoculant. For the test samples, 30 gram of compost was mixed with 100 mL of a 1 wt% solution of a stabilized hydrogen peroxide composition provided herein in water in a 500 mL Gibco bottle and maintained at 19°C for 2 hours, shaken every 15 minutes on a shaker table. Duplicate samples were prepared. The stabilized hydrogen peroxide composition included about 44 wt% hydrogen peroxide and 6.5 wt% D-sorbitol, with a resulting ratio of hydrogen peroxide to D-sorbitol of about 6.8:1. After mixing for 2 hours, the contents of each bottle was separately deposited into a 20 micron nylon stocking and washed with 1 L of water, and the solids were pressed to remove excess water. The washed treated material from the stocking was used as the test material inoculant.

[0077] Samples of 27 eyepieces of potato were arranged in a 3^9 matrix. The surface of the potato samples in each matrix was sprayed with water, and 25-30 gram of each of the abovedescribed inoculants were separately used to inoculate the surface of each of the matrices separately (2 matrices for the negative control, 2 matrices for the positive control, and 2 matrices for the test product). The samples were maintained under conditions promoting growth, and the samples were watered as needed. All of the eyepiece samples grew shoots and roots, and the samples were evaluated after 3 months of growth for wart formation. The results are shown in FIG. 1. It was found that there was good infection and wart production in the positive control, and no infection or wart formation in the negative control. Treatment with the stabilized hydrogen peroxide composition had a negative effect on wart formation, and appeared to consistently suppress wart development, as no wart formation occurred. The treatment effects were found to be reproducible.

[0078] While exemplary embodiments of the present disclosure have been described with reference to the accompanying drawings, it will be understood by experts in the art or those of ordinary skill in the art that the present disclosure may be variously modified and changed without departing from the spirit and scope of the present disclosure as defined by the appended claims.

[0079] Therefore, the technical scope of the present disclosure should not be limited by the content described in the detailed description of the specification but should be defined by the claims.

Claims

CLAIMSWHAT IS CLAIMED IS:

1. A method of suppressing wart formation in potatoes caused by Synchytrium endobioticum. comprising:treating water with a stabilized hydrogen peroxide composition to produce a treated water, wherein the stabilized peroxide composition comprises water, hydrogen peroxide, and a sugar alcohol, wherein the sugar alcohol is selected from the group consisting of sorbitol, xylitol, mannitol, lactitol, maltitol, erythritol, isomalt, and combinations thereof, and the stabilized peroxide composition contains no silver, organophosphonate, peroxyacetic acid, peracid, or stannate;treating seed potatoes with the treated water prior to planting; andadministering the treated water via irrigation after planting for a time period in a range of from 60 days to 140 days.

2. The method of claim 1, wherein the treated water is administered from after planting until harvest.

3. The method of claim 1 or 2, wherein the irrigation delivers the treated water to roots.

4. The method of any one of claims 1 to 3, wherein administering the treated water is via a drip feed irrigation or micro-irrigation system.

5. The method of any one of claims 1 to 3, wherein administering the treated water is via a spray irrigation or sprinkler irrigation system.

6. The method of any one of claims 1 to 3, wherein administering the treated water is via a subirrigation system.

7. The method of any one of claims 1 to 6, wherein the treated water contains a concentration of the stabilized hydrogen peroxide composition of from about 0.005 wt% to 5 wt% based on the weight of the treated water.

8. A method of inhibiting or preventing fungal spore germination of Synchytrium endobioticum in soil or on a surface of a potato plant, the method comprising:detecting a presence of Synchytrium endobioticum in the soil to identify an infected soil;treating water with a stabilized hydrogen peroxide composition to produce a treated water, wherein the stabilized peroxide composition comprises water, hydrogen peroxide, and a sugar alcohol, wherein the sugar alcohol is selected from the group consisting of sorbitol, xylitol, mannitol, lactitol, maltitol, erythritol, isomalt, and combinations thereof, and the stabilized peroxide composition contains no silver, organophosphonate, peroxyacetic acid, peracid, or stannate; andadministering the treated water to the infected soil.

9. The method of claim 8, wherein the detecting is done by:a) direct microscopic examination of the soil for sporangia from Synchytrium endobiolicum orb) a molecular testing method to detect the presence of Synchytrium endobioticum DNAin the soil; orc) a combination of a) and b).

10. The method of claim 9, wherein the molecular testing method is a PCR-based detection method.

11. The method of any one of claims 8 to 10, wherein the treated water contains a concentration of the stabilized hydrogen peroxide composition of from about 0.1 wt% to 5 wt% based on the weight of the treated water.

12. The method of any one of claims 8 to 11, further comprising:removing plants from in and around the infected soil;providing a temporary watertight dam around the infested area to enclose the infested area and produce a dammed area;filling the dammed area with the treated water to a level that an upper surface of the soil in the dammed area is continuously submerged under the treated water; and maintaining the dammed area filled with the treated water for a period of at least 5 weeks.

13. The method of claim 12, wherein a height of the temporary watertight dam above the upper surface of the soil in the dammed area is 10 cm to 100 cm, measured from the upper surface of the soil to the highest point of the temporary watertight dam above the upper surface of the soil.

14. The method of claim 12 or 13, wherein the temporary watertight dam comprises a high-density polyethylene, a polyethylene terephthalate resin, a polycarbonate resin, a reinforced polyethylene resin, a reinforced polypropylene resin, an ethylene propylene diene monomer resin, a polyvinyl chloride resin, or a combination thereof.

15. A method of increasing potato resistance to wart formation caused by Synchytrium endobioliciim. the method comprising:treating water with a stabilized hydrogen peroxide composition to produce a treated water, wherein the stabilized peroxide composition comprises water, hydrogen peroxide, and a sugar alcohol, wherein the sugar alcohol is selected from the group consisting of sorbitol, xylitol, mannitol, lactitol, maltitol, erythritol, isomalt, and combinations thereof, and the stabilized peroxide composition contains no silver, organophosphonate, peroxyacetic acid, peracid, or stannate;administering the treated water via irrigation to soil for a time period in a range of from 1 day to 14 days prior to planting;treating seed potatoes with the treated water prior to planting for a period of 1 hour to 36 hours prior to planting; andadministering the treated water via irrigation after planting for a time period in a range of from 60 days to 140 days.

16. The method of claim 15, wherein the treated water is administered from after planting until harvest.

17. The method of claim 15 or 16, wherein the irrigation delivers the treated water to roots.

18. The method of any one of claims 1 to 3, wherein administering the treated water is via:a) a drip feed irrigation or micro-irrigation system; orb) a spray irrigation or sprinkler irrigation system; orc) a subirrigation system; ord) any combination of a) to c).

19. The method of any one of claims 1 to 6, wherein the treated water contains a concentration of the stabilized hydrogen peroxide composition of from about 0.03 wt% to 3 wt% based on the weight of the treated water.

20. The method of any one of claims 1 to 19, wherein in the stabilized hydrogen peroxide composition:the hydrogen peroxide is present in an amount from about 5 wt% to 50 wt% based on the total weight of the composition; andthe sugar alcohol is present in an amount form about 0.5 wt% to 15 wt% based on the total weight of the composition.

21. The method of any one of claims 1 to 20, wherein in the stabilized hydrogen peroxide composition, a weight ratio of the hydrogen peroxide to the sugar alcohol is from about 4:1 to 100:1.

22. The method of any one of claims 1 to 21, wherein the stabilized hydrogen peroxide composition further comprising a carboxylic acid selected from the group consisting of formic acid, acetic acid, citric acid, lactic acid, glycolic acid, malic acid, oxalic acid, propionic acid, benzoic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, tartaric acid, salicylic acid, and combinations thereof.

23. The method of claim 22, wherein the carboxylic acid is present in an amount from about 0.1 wt% to 10 wt% based on the total weight of the composition.

24. The method of claims 22 or 23, wherein a weight ratio of the hydrogen peroxide to the carboxylic acid in the stabilized hydrogen peroxide composition is from about 1.5: 1 to 60: 1.

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