Patent Application
20240049707
The present invention relates in general to a compound having fungicidal and bactericidal properties for agricultural uses.
Plant pests and diseases represent major challenges to productivity in modern agriculture. Soil-borne plant pathogens cause crucial damage to agricultural crops. The phytopathogenic fungus Rhizoctonia spp. belongs to phylogenetic lineage of Basidiomycetes. It causes a wide range of commercially significant plant diseases, such as brown patch, damping off in seedlings, root rot and belly rot in vegetable crops and sheath blight in rice. All Rhizoctonia diseases, and subsequent secondary infections in plants are difficult to control (Erlacher et al., 2014).
Pythium spp. is phytopathogenic fungus-like organism which belongs to phylogenetic lineage of eukaryotic microorganisms called Oomycetes which causes the widespread “damping off” disease of tobacco, tomato, mustard, chilies and cress seedlings (Martin & Loper, 2010).
Fusarium spp. is a large genus of filamentous fungi belonging to phylogenetic lineage of Ascomycetes. Many species of Fusarium are pathogenic to plants and cause serious diseases like wilt or ‘rot’ of economically important plants, mostly vegetables. In addition, Fusarium species infects cereals causing head blight and ear rot in maize and cause to mycotoxins accumulation under certain conditions (J. E. E. Jenkins, Y. S. Clark and A. E. Buckle, 1998).
Sclerotinia spp. is a plant pathogenic fungus belonging to phylogenetic lineage of Ascomycetes. Sclerotinia spp. causes to disease called white mold in many plant hosts, most of them vegetables (https://anrcatalog.ucanr.edu/pdf/8042.pdf).
Pseudomonas spp. is a plant pathogenic bacterial genus which is virulent in the diverse arrays of crop plants and causes to significant leaf and stem lesions. Pseudomonas spp. causes the following diseases in economically significant crops plants and orchards such as: pith necrosis in parsnip and tomato, brown blotch and leaf sheath brown rot in rice, bacterial canker in almonds and olive knot disease in olives (Moore L. W., 1988; Hofte M. and De Vos P., 2006). A variety of methods have been tested for the management of Pseudomonas spp. in crop plants. They include cultural management, host resistance, biological control with microbial antagonists and chemical control. None of them gives full control.
The number of available active ingredients for crop protection purposes against these diseases is diminishing from year to year due to increasing pest resistance, erratic climatic conditions and mounting regulatory pressure. New active ingredients are urgently needed for development of novel environmentally sustainable crop protection solutions.
In one aspect, the present invention is directed to a pesticide composition comprising Licochalcone C or an agriculturally acceptable salt thereof as an active pesticidal ingredient.
In another aspect, the present invention provides a method for controlling, preventing, reducing or eradicating plant-pathogen infestation or instances thereof, on a plant, plant organ, plant part, or plant propagation material, the method comprising: applying to a plant, plant organ or plant propagation material, or to the soil surrounding said plant, a pesticidal effective amount of Licochalcone C or the pesticide formulation of any one of the below mentioned embodiments, wherein said plant-pathogen is a member selected from: an order of the class Agaricomycetes; a genus of the family Pythiaceae, a genus of the family Sclerotiniaceae selected from Sclerotinia and Fusarium, and family of the order Pseudomonadales.
It has been found in accordance with the present invention that Licochalcone C is a potent pesticide against Rhizoctonia solani, a member of the class Agaricomycetes; Pythium aphanidermatum, a member of the family Pythiaceae; Sclerotinia sclerotiorum and Fusarium oxysporum, members of the family Sclerotiniaceae; and Pseudomonas syringae, a member of the order Pseudomonadales.
The CAS registry identifies Licochalcone C as (E)-3-[4-hydroxy-2-methoxy-3-(3-methylbut-2-enyl)phenyl]-1-(4-hydroxyphenyl)prop-2-en-1-one of the following formula:
The CAS registry number is 144506-14-9. Licochalcone C is a member of the class of retrochalcones.
In certain embodiments, the pesticide composition further comprises an agriculturally suitable or acceptable solvent or solubilising agent.
In certain embodiments, the agriculturally acceptable solvent or solubilising agent is a water-miscible solvent capable of dissolving or solubilising Licochalcone C.
In certain embodiments, the water-miscible solvent capable of dissolving or solubilising Licochalcone C is a polar solvent, such as an alcohol, a ketone, a lactone, a keto-alcohol, a glycol, a glycoether, an amide, an alkanolamine, a sulfoxide and a pyrolidone.
In particular embodiments, the composition comprises a solvent selected from dimethyl-sulfoxide or ethanol, and a polysorbate-type nonionic surfactant that is polysorbate 20.
In another aspect, the present invention provides a method for controlling, preventing, reducing or eradicating plant-pathogen infestation or instances thereof, on a plant, plant organ, plant part, or plant propagation material, the method comprising: applying to a plant, plant organ or plant propagation material, or to soil surrounding said plant, a pesticidally effective amount of Licochalcone C or pesticidally active salts thereof as an active pesticidal ingredient, or the pesticide composition of any one of the above embodiments, wherein said plant-pathogen is a member selected from: an order of the class Agaricomycetes; a genus of the family Pythiaceae, a genus of the family Sclerotiniaceae selected from Sclerotinia and Fusarium, and a family of the order Pseudomonadales.
The method of treatment of the present invention is useful for example against the following diseases: Rhizoctonia spp. causing brown patch, damping off in seedlings, root rot and belly rot in vegetables and sheath blight in rice; “damping off” disease caused by Pythium spp. in tobacco, tomato, cucumbers, mustard, chilies and cress seedlings; Fusarium spp. causing wilt or ‘rot’ of vegetables, bananas; Fusarium spp. head and ear rot in maize; Fusarium graminearum head blight in small grains; white mold caused by Sclerotinia spp. in many plants, mostly vegetables; Pseudomonas spp. pith necrosis in parsnip and tomato, brown blotch and leaf sheath brown rot in rice, bacterial canker in almonds and olive knot disease in olives.
In certain embodiments, the plant-pathogen is a member of the class Agaricomycetes.
In certain embodiments, the Agaricomycetes plant-pathogen is a member of the order Cantharellales.
In certain embodiments, the Cantharellales plant-pathogen is a member of the family Ceratobasidiaceae.
In certain embodiments, the Ceratobasidiaceae plant-pathogen is a member of the genus Rhizoctonia, such as Rhizoctonia solani, Rhizoctonia bataticola also known as Macrophomina phaseolina, Rhizoctonia carotae also known as Fibulorhizoctonia carotae, Rhizoctonia cerealis-asexual form of Ceratobasidium cereale, Rhizoctonia crocorum also known as Thanatophytum crocorum (asexual form of Helicobasidium purpureum), Rhizoctonia fragariae which is asexual form of Ceratobasidium cornigerum, Rhizoctonia goodyerae-repentis also known as Ceratobasidium cornigerum, Rhizoctonia oryzae also known as Waitea circinate, and Rhizoctonia ramicola also known as Ceratorhiza ramicola (asexual form of Ceratobasidium ramicola).
In certain embodiments, the plant-pathogen is Rhizoctonia solani.
In certain embodiments, the plant-pathogen is a member of the family Pythiaceae.
In certain embodiments, the Pythiaceae plant-pathogen is a member of the genus Pythium, such as Pythium aphanidermatum and Pythium ultimum.
In certain embodiments, the plant-pathogen is the species Pythium aphanidermatum.
In certain embodiments, the plant-pathogen is a member of Sclerotiniaceae selected from Sclerotinia and Fusarium.
In certain embodiments, the plant-pathogen is a member of the genus Fusarium, such as Fusarium oxysporum, Fusarium avenaceum, Fusarium bubigeum, Fusarium circinatum, Fusarium crookwellense, Fusarium culmorum, Fusarium graminearum, Fusarium langsethiae, Fusarium poae, Fusarium proliferatum, Fusarium solani, Fusarium sporotrichioides, Fusarium tricinctum, Fusarium venenatum, Fusarium verticillioides, and Fusarium virguliforme.
In certain embodiments, the plant-pathogen is Fusarium oxysporum.
In certain embodiments, the plant-pathogen is a member of the genus Sclerotinia such as Sclerotinia sclerotiorum, Sclerotinia borealis, Sclerotinia bulborum (Wakker) Sacc., Sclerotinia homoeocarpa F. T. Benn., Sclerotinia minor Jagger, Sclerotinia ricini, Sclerotinia sclerotiorum (Lib.) de Bary, Sclerotinia spermophila Noble, Sclerotinia sulcate, Sclerotinia trifoliorum Erikss., and Sclerotinia veratri.
In certain embodiments, the plant-pathogen is Sclerotinia sclerotiorum.
In certain embodiments, the plant-pathogen is a member of the order Pseudomonadales.
In certain embodiments, the Pseudomonadales plant-pathogen is a member of the family Pseudomonadaceae.
In certain embodiments, the Pseudomonadaceae plant-pathogen is a member of the genus Pseudomonas, such as Pseudomonas aeroginosa and Pseudomonas syringae.
The pesticide composition of the present invention may be formulated into a formulation to facilitate application of the active pesticidal ingredient.
The formulation may be a water-miscible formulation, such as a suspension concentrate (SC), a capsule suspension (CS), water-dispersible granules (WG), an emulsifiable concentrate (EC), a wettable powder (WP), a soluble (liquid) concentrate (SL), and a soluble powder (SP).
This formulation may further comprise at least one solvent or solubilising agent, adjuvant, carrier, diluent, and/or surfactant.
Non-limiting examples of adjuvants are activator adjuvants, such as cationic, anionic or non-ionic surfactants, oils and nitrogen-based fertilisers capable of improving activity of the pesticide product. Oils may be crop oils, such as paraffin or naphtha-based petroleum oil, crop oil concentrates based on emulsifiable petroleum-based oil, and vegetable oil concentrates derived from seed oil, usually cotton, linseed, soybean, or sunflower oil, used to control grassy weeds. Nitrogen-based fertilisers may be ammonium sulphate or urea-ammonium nitrate.
Non-limiting examples of solubilising agents or solvents are petroleum-based solvents, the aforementioned oils, liquid mixtures of fatty acids, ethanol, glycerol and dimethyl sulfoxide. The agriculturally acceptable solvent or solubilising agent may be a water-miscible solvent capable of dissolving or solubilising Licochalcone C, such as a polar solvent, e.g., an alcohol, a ketone, a lactone, a keto-alcohol, a glycol, a glycoether, an amide, an alkanolamine, a sulfoxide and a pyrrolidone.
Non-limiting examples of carriers are precipitated silica, colloidal silica, attapulgite, china clay, talc, kaolin and combinations thereof.
The pesticide formulation may further comprise a diluent, such as lactose, starch, urea, water soluble inorganic salts and combination thereof.
The pesticide formulation may further comprise one or more surfactants, such as polysorbate-type non-ionic surfactant, styrene acrylic dispersant polymers, acid resin copolymer-based dispersing agents, potassium polycarboxylate, sodium alkyl naphthalene sulphonate blend, sodium (diisopropyl)naphthalene sulphonate, sodium salt of naphthalene sulphonate condensate, lignin sulphonate salts and combinations thereof.
Licochalcone C, composition, or formulation comprising it, is applied in the method of any one of the above embodiments to the plant or part, organ or plant propagation material thereof by spraying, immersing, dressing, coating, pelleting or soaking.
The term “pesticide” as used herein refers to compounds effective for controlling, preventing, reducing or eradicating plant-pathogen infestation or instances thereof, on a plant, plant organ, plant part, plant propagation material or the soil surrounding said plant and includes antibacterial agents, fungicides, herbicides, and insecticides.
The term “active pesticidal ingredient” as herein refers to a compound that is effective as a pesticide.
The term “plant organ” as used herein refers to the leaf, stem, root, and reproductive structures.
The term “plant part” as used herein refers to a vegetative plant material such as a cutting or a tuber; a leaf, flower, bark or a stem.
The term “plant propagation material” as used herein refers to a seed, root, fruit, tuber, bulb, rhizome, or part of a plant.
The term “pesticidal effective amount” as used herein refers to an amount of the pesticide that is effective for controlling, preventing, reducing or eradicating plant-pathogen infestation or instances thereof, on a plant, plant organ, plant part, plant propagation material or the soil surrounding said plant.
The terms “class”, “order”, “family”, “genus”, and “species” are used herein according to Art 3.1 of the International Code of Nomenclature for algae, fungi, and plants.
The term “comprising”, used in the claims, is “open ended” and means the elements recited, or their equivalent in structure or function, plus any other element or elements which are not recited. It should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It needs to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression “a composition comprising x and z” should not be limited to compositions consisting only of compounds x and z. Also, the scope of the expression “a method comprising the steps x and z” should not be limited to methods consisting only of these steps.
As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. Well-known functions or constructions may not be described in detail for brevity and/or clarity.
Unless otherwise indicated, all numbers used in this specification are to be understood as being modified in all instances by the term “about”. Unless specifically stated, as used herein, the term “about” is understood as within a range of normal tolerance in the art, for example within two standard deviations of the mean. In one embodiment, the term “about” means within 10% of the reported numerical value of the number with which it is being used, preferably within 5% of the reported numerical value. For example, the term “about” can be immediately understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. In other embodiments, the term “about” can mean a higher tolerance of variation depending on for instance the experimental technique used. Said variations of a specified value are understood by the skilled person and are within the context of the present invention. As an illustration, a numerical range of “about 1 to about 5” should be interpreted to include not only the explicitly recited values of about 1 to about 5, but also include individual values and sub-ranges within the indicated range. Thus, included in this numerical range are individual values such as 2, 3, and 4 and sub-ranges, for example from 1-3, from 2-4, and from 3-5, as well as 1, 2, 3, 4, 5, or 6, individually. This same principle applies to ranges reciting only one numerical value as a minimum or a maximum. Unless otherwise clear from context, all numerical values provided herein are modified by the term “about”. Other similar terms, such as “substantially”, “generally”, “up to” and the like are to be construed as modifying a term or value such that it is not an absolute. Such terms will be defined by the circumstances and the terms that they modify as those terms are understood by those of skilled in the art. This includes, at very least, the degree of expected experimental error, technical error and instrumental error for a given experiment, technique or an instrument used to measure a value.
The invention will now be illustrated by the following non-limiting Examples.
Summary:
Diluted in DMSO Licochalcone C was added to microplate wells and mixed with 50 μl of hyphae suspension and growth of the fungus, starting from blended hyphae, was monitored by plate reader and visual inspection.
The following Materials, methods and equipment were used:
Materials: PDAC, PDBC, DMSO
Equipment: Plate reader, Centrifuge, Shaker, Incubator
Method:
Inoculum Preparation of Rhizoctonia solani Hyphae:
Grow Rhizoctonia on PDAC in 90 mm petri plates to get growing hyphae within 1-4 days.
Add 50 ml of PDBC medium into a sterile 250 ml Erlenmeyer flask.
Cut the solid medium by scalpel to several small pieces and insert them into the Erlenmeyer flask.
Grow the culture for 2-4 days using shaker at 27° C. and 150 RPM.
Discard the liquid and pour the hyphae on an empty Petri dish.
Cut many small pieces from the hyphae using a scalpel and insert them into a sterile 250 ml Erlenmeyer flask with 50 ml of PDBC medium.
Prepare 4 bottles with culture and grow for 3 days at 27° C. shaking at 150 RPM.
Chill the culture in the fridge for 1 h.
Pour the cold culture into a 250 ml beaker.
Add 20 ml of cold PDBC, so that the mixture will cover the blender knife.
Blend the culture with a blender for 2 min on ice at maximum speed, move the blender up and down several times.
Keep the mixture on ice.
Transfer about 5 ml of the blended mixture into a 15 ml tube on ice.
Homogenize the culture in the 15 ml tube for 2 min on ice, move the tube up and down as needed.
Homogenize several batches of 5 ml as above to prepare the amount that is needed (5 ml of homogenized culture would make about 100 ml of inoculum).
Dilute a portion of the homogenate 10-fold to check the concentration of the homogenate.
The concentration of the suspension should be 4×104 CFU/ml (diluted 10-fold concentration should be 4000 CFU/ml).
Dilute the inoculum stock 1:20 in PDBC—1 ml in 20 ml, or calculate the dilution needed, to prepare final concentration of 2000 CFU/ml. The amount in each well should be about 100 CFU.
Microplate Preparation for Licochalcone C Bioactivity Experiment:
Screening of Plates:
Results: see Example 6.
Summary:
Diluted in DMSO Licochalcone C was added to microplate wells and mixed with 50 μl of zoospores in PDBC suspension and the growth of the fungus, starting from zoospores, was monitored by plate reader and visual inspection.
The following Materials, methods and equipment were used:
Materials:
Equipment:
Plate reader, Centrifuge, Shaker, Incubator
Method:
Inoculum Preparation of Pythium Hyphae:
Grow Pythium aphanidermatum on SCH in 90 mm petri plates to get sporulating hyphae. Each plate will produce 50 ml of zoospores suspension which will be enough for bioactivity screening for ten 96-well plates.
Add 60 ml of sterile H2O into a sterile 250 ml Erlenmeyer flask.
Cut the solid medium of 2 plates by scalpel to 12 pieces (each plate) and insert them into the Erlenmeyer flask (the solid pieces should be covered by the water).
Let the hyphae sporulate overnight at 17° C.
Shake the Erlenmeyer flask by hand to suspend the zoospores.
Filter the suspension into 50 ml tube through 16-layer gauze.
Transfer the suspension into a sterile 500 ml bottle.
Discard the solids and disinfect the Erlenmeyer flask with hypochlorite.
Chill the zoospore suspension on ice.
Evaluate the zoospores concentration in the suspension (the concentration should be 1000-4000 spores/ml).
Dilute the suspension by sterile fridge cold distilled H2O in a sterile 500 ml bottle.
Add the same volume (as the suspension) sterile fridge cold 2:PDBC to get 500-2000 spores/ml inoculum. This dilution will result in the amount of 25-100 zoospores in each well.
Keep the zoospore suspension inoculum on ice.
Microplate Preparation for Licochalcone C Bioactivity Experiment:
Screening of Plates:
Summary:
Diluted in DMSO Licochalcone C was added to microplate wells and mixed with freshly prepared spore suspension and growth of the fungus, starting from frozen spores, was monitored using the plate reader and by visual inspection.
Background:
Fusarium is a fungus of belonging to the Ascomycetes, and it is a soil borne pathogen. It is quite easy to produce large amounts of spores of Fusarium and they survive in liquid 60% glycerol at −20° C. Thus, we used frozen spores' stock in the bioactivity screening experiments rather than prepare fresh spores for each experiment.
Aim:
To determine the effect of Licochalcone C on the survival and growth of Fusarium.
The following materials, methods and equipment were used:
Materials: PDAC, PDBC, DMSO
Equipment: Plate reader, Centrifuge, Shaker, Incubator
Method:
Fusarium Spore Suspension Preparation:
Spore Suspension Preparation for Screening:
Microplate Preparation for Licochalcone C Bioactivity Experiment:
Readout of the Plates:
Results: see Example 6.
Summary:
Diluted in DMSO purified Licochalcone C was added to microplate wells and mixed with 50 μl of hyphae suspension and growth of the fungus starting from blended hyphae was monitored by visual inspection.
Sclerotinia sclerotiorum is a fungus of belonging to the Ascomycetes and it is a soil borne pathogen. It is difficult to produce large amounts of spores of Sclerotinia sclerotiorum, that led to decision to use hyphae in this screening rather than spores for inoculation.
The following materials, methods and equipment were used:
Materials: PDBC, PDA, PDAT, PDBT, DMSO
Equipment: Centrifuge, Shaker, Incubator
Method:
Inoculum Preparation of Sclerotinia sclerotiorum Hyphae:
Grow Sclerotinia sclerotiorum on PDA in tube at 21° C. for 4 days.
Transfer agar block and grow Sclerotinia sclerotiorum on PDAT in 90 mm Petri dishes at 21° C. to get growing hyphae within 3 days.
Add 50 ml of PDBT medium into a sterile 250 ml square flask.
Cut the solid medium by scalpel to 15 very small pieces (1×5 mm) and insert them into the square flask.
Grow the culture for 2 days using shaker at 21° C. and 130 RPM.
Discard the liquid and pour the hyphae on an empty Petri dish.
Cut many small pieces from the hyphae (avoid using the agar pieces) using a scalpel and insert them into a sterile 250 ml square flask containing 50 ml of PDBT medium.
Grow for 2 days at 21° C., shaking at 130 RPM to get fast growing dispersed hyphae.
Chill the culture in the fridge for 1 hour.
Pour the cold culture into a 50 ml tube.
Keep the mixture on ice.
Transfer about 5 ml of the blended mixture into a 15 ml tube on ice.
Homogenize the culture in the 15 ml tube for 2 min on ice.
Homogenize several batches of 5 ml as above to prepare the amount that is needed (5 ml of homogenized culture would make about 50 ml of inoculum).
Dilute a portion of the homogenate 10-fold to check the concentration of the homogenate. the concentration of the suspension should be 2×104 CFU/ml (diluted 10-fold concentration should be 2000 CFU/ml).
Dilute the inoculum stock 1:10 in PDBC—2 ml in 20 ml, or calculate the dilution needed, to prepare final concentration of 2000 CFU/ml. The final number of hyphae should be 100 CFU in each well.
Microplate Preparation for Activity Experiment:
Screening of Plates:
Results: see Example 6.
Background:
Pseudomonas is a rod-shaped Gram-negative bacterium. Frozen bacterial stock in 60% glycerol was used as an inoculum for the bioactivity screening experiments.
Summary:
Diluted in DMSO Licochalcone C was added to microplate wells and mixed with 100 μl of frozen bacteria suspension and growth of the Pseudomonas was monitored by visual inspection.
The following materials, methods and equipment were used:
Materials: LB, LBA, DMSO
Equipment: Centrifuge, Shaker, Incubator
Method:
Pseudomonas Suspension Preparation:
Pseudomonas Suspension Preparation for Bioactivity Screening Experiment:
Microplates' Preparation for Bioactivity Screening Experiment:
Bioactivity Screening of Microplates:
Record the results using the following interpretation: clear=3 (no growth of bacteria), turbid=1(normal bacterial growth), inconclusive=2 (very low turbidity compared to growth in 0.5% DMSO solution)
Results: see Example 6.
Statistical Analysis for In-Vivo Validation Experiments.
To evaluate the effect of a Licochalcone C in infected plants compared to control plants (infected but not treated) the data was analysed by Student's t-test and the p-value is calculated. The minimum number of repeats in each experiment was 3. Results were considered significant if p<0.05. The data presented as mean with standard error mean from biological replicates. * means that p-value <0.05, ** means that p-value is <0.01, # means that p-value <0.1.
In-Vitro Screening Matrix
Licochalcone C was screened against selected agricultural pests (as indicated in the tables below). Bioactivity values are in % and reflect the potential of eradicating the target pests.
Rules for Bioactivity Relative Value Calculation (Expressed in % from Maximal Value)
Rhizoctonia solani
Pythium aphanidermatum
Fusarium oxysporum
Sclerotinia sclerotiorum
Pseudomonas syringae
In summary, Licochalcone C is effective pesticide against the following pests: Pythium aphanidermatum (positive results are provided below in in-vivo results section), Rhizoctonia solani (positive results are provided below in in-vivo results section), Sclerotinia sclerotiorum, Fusarium oxysporum and Pseudomonas syringae.
Formulation 1—the formulation with final concentration of 400 ppm is composed of:
To prepare solution A Licochalcone C was dissolved in water to get 0.1% solution and sonicated for 5-10 mins. Afterwards, Na2CO3 was added to the final concentration of 25% and mixed well (pH of this solution should be 8).
A, B, C and D were mixed well to get the final formulation. The final formulation 1 was either applied as 400 ppm or diluted to the required concentrations and applied to cucumber seedlings.
Formulation 2—the formulation with final concentration of 400 ppm is composed of:
To prepare solution A Licochalcone C was dissolved in ethanol to get 1% solution and sonicated for 5-10 mins. Afterwards the non-ionic detergent Tween 20 was added to the final concentration of 1% and mixed well. The solution was evaporated under nitrogen to get 10% Licochalcone C solution.
A, B, C and D were mixed well to get the final formulation. The final formulation 4 was either applied as 400 ppm or diluted to the required concentrations and applied to cucumber seedlings.
General description: Pythium aphanidermatum disease severity development was evaluated following preventative treatment by Licochalcone C (LIC)
Pythium inoculum Preparation:
Seedlings' Germination Conditions.
Treatment Application
Inoculation of Soil:
Growth and Analysis:
Results: Licochalcone C showed excellent results in preventing Pythium disease in cucumber seedling with efficacy up to 100% with 2 different types of formulations in dosages between 100 to 400 ppm.
General description: Rhizoctonia disease severity were evaluated following preventative treatment with Licochalcone C. Hyphae were used to infect 6 days old cucumber seedlings with concomitant treatment with Licochalcone C
Rhizoctonia inoculum Preparation:
Cucumber Seedlings Germination Protocol
Treatment Application
Inoculation of Soil:
Results: Licochalcone C showed excellent results in preventing Rhizoctonia disease in cucumber seedlings with efficacy between 66.66 to 100% with 2 different types of formulations in dosages between 100 to 400 ppm.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102020000031712 | Dec 2020 | IT | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IL2021/051303 | 11/3/2021 | WO |
