Method for controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchus, especially rice stem-tipped nematodes

Abstract

The present invention relates to a method for controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchoides spp., which method comprises applying the compound cyclobutrifluram or a pesticidal composition comprising cyclobutrifluram to a plant crop, its locus or its propagation material.

Description

Technical Field

[0001] The present invention relates to a method for controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchus, in particular the rice stem-tipped nematode. Background Art

[0002] Aphelenchus species are a genus of nematodes that globally infect annual crops such as rice, strawberries, beans, cowpeas, soybeans, cotton, and ornamental plant species (e.g., chrysanthemums, roses, gladioli, violets, and begonias). The nematodes attack the young, tender tissues of the aerial parts of the plant (stems, leaves, buds, flowers, and pods), leading to significant reductions in crop yields, primarily when the attack is concentrated in the reproductive parts of the plant (flowers, inflorescences, and pods). The nematodes spend part of their life cycle in the roots of the plant (like most plant-parasitic nematodes) and part of their life cycle in the aerial parts of the plant, where damage is more pronounced. Therefore, there is an urgent need to provide effective methods for controlling or preventing infestations of Aphelenchus species nematodes, particularly the rice stem-tipped nematode.

[0003] The present invention provides improved methods for controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchus, particularly Aphelenchus oryzae. DETAILED DESCRIPTION

[0004] Cyclobutylcarboxamide compounds and methods for their preparation are disclosed in WO 2013 / 143811 and WO 2015 / 003951. Recently, a cyclobutylcarboxamide, cyclobutaflutol (ISO name, CAS RN [1460292-16-3]), developed as a nematicide, was published (http: / / pmonline.azurewebsites.net / _Main / Pesticide.aspx). The chemical structure of cyclobutaflutol is

[0005]

[0006] Cyclodextrin is known to be active against root-knot nematodes such as Meloidogyne and cyst-forming nematodes such as Heterodera. These nematode species are soil-based and attack the root systems of many plants. However, nematodes of the genus Aphelenchus attack the above-ground parts of plants, such as stems, leaves, buds, flowers, and pods. This means that nematodes of the genus Aphelenchus are capable of both ectoparasitism (on the surface of the plant) and endoparasitism (within the plant tissues). Therefore, these nematodes can move around both outside and inside the plant. This makes the task of controlling or preventing infestations by Aphelenchus nematodes very challenging. Potential nematocides not only need to be active against the target nematode species, but must also be able to reach all parts of the plant to effectively control or prevent infestations. Most nematode species currently available are not systemic, meaning they cannot reach all parts of the plant that the Aphelenchus nematodes feed on. This results in less than ideal control of these nematodes.

[0007] It has now been surprisingly discovered that cyclobutaflutol is very effective in controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchus. Therefore, this highly effective compound represents an important new solution for farmers to control or prevent infestation of plants by plant-parasitic nematodes of the genus Aphelenchus. It has been found that cyclobutaflutol is very effective when used as a seed treatment against infestations of rice stem-tipped nematodes. Rice stem-tipped nematodes attack the above-ground parts of plants, which means that cyclobutaflutol is not only able to protect the seeds to which it is applied, but also the plants grown from the treated seeds. Tests have shown that cyclobutaflutol is more effective in protecting plants grown from treated seeds than any commercial standard currently in use. Therefore, cyclobutaflutol provides farmers with an excellent tool for controlling or preventing infestations of nematodes of the genus Aphelenchus, especially rice stem-tipped nematodes.

[0008] Thus, as Example 1, there is provided a method of controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchus, said method comprising applying the compound cytofluan to a crop of plants, the locus thereof or propagation material thereof.

[0009] Cyclobutaflutol as disclosed above represents a cis racemate: the phenyl ring on the left and the pyridyl-C(=O)-NH group on the right are cis to each other on the cyclobutyl ring, as illustrated for compounds of formula (Ia) and formula (Ib):

[0010]

[0011] Thus, the racemic compound of cyclohexane is a 1:1 mixture of compounds of Formula (Ia) and (Ib). The wedge-shaped bonds shown in the compounds of Formula (Ia) and (Ib) represent the absolute stereochemistry, while the thick straight bonds, as shown for cyclohexane, represent the relative stereochemistry in the racemic compound.

[0012] It has also been surprisingly found that one enantiomer of cyclohexene is particularly useful for controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchus.

[0013] Thus, as embodiment 2, there is provided a method according to any one of embodiment 1, wherein cyclohexane is in the form of the (1S, 2S) stereoisomer

[0014]

[0015] As will be appreciated by those skilled in the art, according to the methods described in Examples 1 or 2, cyclofluam is typically applied as part of a pesticidal composition. Thus, as in Example 3, a method for controlling or preventing plant infestation by plant-parasitic nematodes of the genus Aphelenchus is provided, comprising applying a pesticidal composition comprising cyclofluam and one or more formulation adjuvants to a plant crop, its locus, or its propagation material. As in Example 4, a method for controlling or preventing plant infestation by plant-parasitic nematodes of the genus Aphelenchus is provided, comprising applying a pesticidal composition comprising a compound of Formula (Ia) and one or more formulation adjuvants to a plant crop, its locus, or its propagation material. In the method according to Example 5, for the pesticidal composition comprising the (1S,2S) and (1R,2R) stereoisomers of cyclofluam, the ratio of the (1S,2S) stereoisomer to its enantiomer (1R,2R) is greater than 1:1. Preferably, the ratio of (1S,2S) to (1S,2S) is greater than 1.5:1, more preferably greater than 2.5:1, especially greater than 4:1, advantageously greater than 9:1, desirably greater than 20:1, and particularly greater than 35:1.

[0016] Also understood as part of the present invention are mixtures containing up to 50%, preferably up to 40%, more preferably up to 30%, especially up to 20%, advantageously up to 10%, desirably up to 5%, in particular up to 3% of the trans stereoisomer of the compound of formula (I) (i.e., wherein the phenyl and pyridyl-C(=O)-NH groups are trans to each other). Preferably, the ratio of cis isomers to their trans isomers is greater than 1.5:1, more preferably greater than 2.5:1, in particular greater than 4:1, advantageously greater than 9:1, desirably greater than 20:1, in particular greater than 35:1.

[0017] As embodiment 6, there is provided the method of any one of embodiments 1 to 5, wherein the pesticidal composition is a suspension concentrate composition.

[0018] As embodiment 7, there is provided a method according to any one of embodiments 1 to 6, the method comprising the following steps:

[0019] Providing a pesticidal composition comprising cyclohexane as defined in any one of embodiments 1 to 6;

[0020] applying the composition to propagation material;

[0021] Planting the propagation material.

[0022] As embodiment 8, there is provided a method according to any one of embodiments 1 to 6, the method comprising the following steps:

[0023] Providing a pesticidal composition comprising cyclohexane as defined in any one of embodiments 1 to 6;

[0024] The composition is applied to a crop of plants or the locus thereof.

[0025] As embodiment 9, there is provided use of cyclohexane or a pesticidal composition comprising cyclohexane as defined in any one of embodiments 1 to 6 for controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchus.

[0026] As embodiment 10, provided is a method or use according to any one of embodiments 1 to 9, wherein the plant-parasitic nematode is Oryza sativa.

[0027] As embodiment 11, provided is a method or use according to any one of embodiments 1 to 10, wherein the plant is selected from rice, strawberry, bean, cowpea, soybean, cotton and ornamental plant species (such as chrysanthemum, rose, gladiolus, violet, begonia).

[0028] As embodiment 12, there is provided a method or use according to any one of embodiments 1 to 10, wherein the plant is selected from rice, soybean and cotton.

[0029] As embodiment 13, there is provided a method or use according to any one of embodiments 1 to 10, wherein the plant is selected from soybean and cotton.

[0030] As embodiment 14, there is provided a method or use according to any one of embodiments 1 to 10, wherein the plant is selected from soybean.

[0031] As Example 15, there is provided a method for growing soybean, the method comprising applying cyclohexane or a pesticidal composition comprising cyclohexane as defined in any one of claims 1 to 6 to its propagation material or treating its propagation material with the cyclohexane or a pesticidal composition comprising cyclohexane.

[0032] As Example 16, there is provided a method for growing cotton, the method comprising applying cyclohexane or a pesticidal composition comprising cyclohexane as defined in any one of claims 1 to 6 to its propagation material or treating its propagation material with the cyclohexane or a pesticidal composition comprising cyclohexane.

[0033] As Example 17, there is provided a method for growing kidney beans, the method comprising applying cyclohexane or a pesticidal composition comprising cyclohexane as defined in any one of claims 1 to 6 to its propagation material or treating its propagation material with the cyclohexane or a pesticidal composition comprising cyclohexane.

[0034] As Example 18, a method for growing strawberry plants is provided, which comprises applying cyclohexane or a pesticidal composition comprising cyclohexane as defined in any one of claims 1 to 6 to its propagation material or treating its propagation material with the cyclohexane or a pesticidal composition comprising cyclohexane.

[0035] As Example 19, a method for growing an ornamental plant species is provided, which comprises applying cyclohexane or a pesticidal composition comprising cyclohexane as defined in any one of claims 1 to 6 to its propagation material or treating its propagation material with the cyclohexane or a pesticidal composition comprising cyclohexane.

[0036] As Example 20, provided is a method for growing rice, the method comprising applying cyclohexane or a pesticidal composition comprising cyclohexane as defined in any one of claims 1 to 6 to its propagation material or treating its propagation material with the cyclohexane or a pesticidal composition comprising cyclohexane.

[0037] As embodiment 21, there is provided a method or use according to any one of claims 1 to 20, wherein the propagation material is a seed.

[0038] As embodiment 22, there is provided a method or use according to any one of claims 1 to 21, wherein the compound cyclohexene is applied to the seeds in an amount of between 5 grams and 100 grams of cyclohexene per 100 kg of seeds.

[0039] As embodiment 23, there is provided a method or use according to any one of claims 1 to 21, wherein the compound cyclohexene is applied to the seeds in an amount between 10 grams and 80 grams of cyclohexene per 100 kg of seeds.

[0040] As embodiment 24, there is provided a method or use according to any one of claims 1 to 21, wherein the compound cyclohexene is applied to the seeds in an amount of between 10 grams and 40 grams of cyclohexene per 100 kg of seeds.

[0041] The preparation of cyclohexane has been disclosed in WO 2013 / 143811 and WO 2015 / 003951, which are incorporated herein by reference.

[0042] The term "seed" encompasses all kinds of seeds and plant propagules, including but not limited to true seeds, seed pieces, suckers, kernels, bulbs, fruits, tubers, grains, rhizomes, cuttings, cuttings, etc. and in preferred embodiments means true seeds.

[0043] According to the method or use according to any one of embodiments 1 to 24, preferably the plant crop, its locus or its propagation material is applied. Preferably, the plant crop or its propagation material is applied, more preferably, the propagation material is applied. The application of cyclopentaflutol or the pesticidal composition comprising cyclopentaflutol can be carried out according to any common application method (e.g., foliar application, drench application, soil application, in-furrow application, etc.).

[0044] The compounds as defined in any one of embodiments 1 to 24 are preferably used for pest control at 1 to 500 g / ha, preferably 10-70 g / ha.

[0045] The methods as defined in any one of Examples 1 to 24 are suitable for use on any plant, including those that have been genetically modified to be resistant to active ingredients (such as herbicides), or those that have been genetically modified to produce biologically active compounds that control infestation by plant pests.

[0046] Typically, cyclohexane is used in the form of a composition (eg, a formulation) containing a carrier. The cyclohexane or a composition comprising cyclohexane as defined in any one of Examples 1 to 5 can be used in different forms, such as aerosol sprays, capsule suspensions, concentrated cold mists, dustable powders, emulsifiable concentrates, oil-in-water emulsions, water-in-oil emulsions, encapsulated granules, fine granules, flowable concentrates for seed treatment, gases (under pressure), gas-producing products, granules, concentrated hot mists, large granules, microgranules, oil-dispersible powders, oil suspensions, oil-soluble liquids, pastes, plant sticks, powders for dry seed treatment, seeds coated with pesticides, soluble concentrates, soluble powders, solutions for seed treatment, suspension concentrates (flowable concentrates), ultra-low volume (ulv) liquids, ultra-low volume (ulv) suspensions, water-dispersible granules or tablets, water-dispersible powders for slurry treatment, water-soluble granules or tablets, water-soluble powders for seed treatment and wettable powders.

[0047] The formulation typically comprises a liquid or solid carrier and optionally one or more conventional formulation adjuvants, which may be solid or liquid adjuvants, for example, non-epoxidized or epoxidized vegetable oils (e.g., epoxidized coconut oil, rapeseed oil or soybean oil), defoamers (e.g., silicone oils), preservatives, clays, inorganic compounds, viscosity modifiers, surfactants, binders and / or tackifiers. The composition may further comprise a fertilizer, a micronutrient donor or other agent that influences plant growth, and includes combinations comprising a compound of the invention and one or more other biologically active agents, such as bactericides, fungicides, nematicides, plant activators, acaricides and insecticides.

[0048] The compositions are prepared in a manner known per se, in the absence of auxiliaries, for example by grinding, screening and / or compressing the solid compound according to the invention, and in the presence of at least one auxiliary agent, for example by intimately mixing and / or grinding the compound according to the invention with one or more auxiliary agents. In the case of the solid compound according to the invention, the grinding / milling of the compound is to ensure a specific particle size.

[0049] Examples of compositions for use in agriculture are emulsifiable concentrates, suspension concentrates, microemulsions, oil dispersibles, directly sprayable or dilutable solutions, spreadable pastes, dilute emulsions, soluble powders, dispersible powders, wettable powders, dusts, granules or capsules in a polymeric substance, said composition comprising at least cyclohexane and the type of composition being chosen to be suitable for the intended purpose and the prevailing circumstances.

[0050] Typically, these compositions comprise from 0.1% to 99% (especially from 0.1% to 95%) of cyclohexane and from 1% to 99.9% (especially from 5% to 99.9%) of at least one solid or liquid carrier, it being possible in principle for 0 to 25% (especially from 0.1% to 20%) of the composition to be surfactant (% in each case being percentages by weight). Although concentrated compositions tend to be preferred for commercial purposes, the end consumer generally uses diluted compositions having significantly lower concentrations of active ingredient.

[0051] Examples of the types of leaf formulations used in premix compositions are:

[0052] GR: Granules

[0053] WP: Wettable Powder

[0054] WG: Water dispersible granules (powder)

[0055] SG: Water-soluble granules

[0056] SL: Soluble Concentrate

[0057] EC: Emulsifiable Concentrate

[0058] EW: Oil-in-water emulsion

[0059] ME: Microemulsion

[0060] SC: Aqueous Suspension Concentrate

[0061] CS: Aqueous Capsule Suspension

[0062] OD: Oil-based suspension concentrates, and

[0063] SE: aqueous suspension emulsion.

[0064] Examples of the types of seed treatment formulations used in premix compositions are:

[0065] WS: Wettable powder for seed treatment slurry

[0066] LS: Solution for seed treatment

[0067] ES: Emulsion for seed treatment

[0068] FS: Suspension concentrate for seed treatment

[0069] WG: water dispersible granules, and

[0070] CS: aqueous capsule suspension.

[0071] Examples of suitable formulation types for tank-mix compositions are solutions, dilute emulsions, suspensions or mixtures thereof, and dusts.

[0072] In view of the nature of the formulation, the application method (such as foliar application, drenching application, spraying application, atomization application, dusting application, broadcasting application, coating application or pouring application) can be selected according to the intended purpose and the prevailing circumstances.

[0073] Tank-mix compositions are typically prepared by diluting one or more premix compositions containing different pesticides and, optionally, additional adjuvants, with a solvent (eg, water).

[0074] Suitable carriers and adjuvants can be solid or liquid and are the substances customary in formulation technology, such as natural or regenerated mineral substances, solvents, dispersants, wetting agents, tackifiers, thickeners, binders or fertilizers.

[0075] Generally, tank mix formulations for foliar or soil application contain 0.1% to 20%, especially 0.1% to 15%, of the desired ingredients and 99.9% to 80%, especially 99.9% to 85%, of solid or liquid adjuvants (including, for example, solvents such as water), wherein the adjuvant may be a surfactant, in an amount of 0 to 20%, especially 0.1% to 15%, based on the tank mix formulation.

[0076] Typically, premix formulations for foliar application contain 0.1% to 99.9%, especially 1% to 95% of the desired ingredient and 99.9% to 0.1%, especially 99% to 5%, of a solid or liquid adjuvant (including, for example, a solvent such as water), where the adjuvant may be a surfactant, in an amount of 0 to 50%, especially 0.5% to 40%, based on the premix formulation.

[0077] Typically, tank mix formulations for seed treatment applications contain 0.25% to 80%, especially 1% to 75%, of the desired ingredients and 99.75% to 20%, especially 99% to 25%, of solid or liquid adjuvants (including, for example, solvents such as water), wherein the adjuvant may be a surfactant, in an amount of 0 to 40%, especially 0.5% to 30%, based on the tank mix formulation.

[0078] Typically, premix formulations for seed treatment applications contain 0.5% to 99.9%, especially 1% to 95% of the desired ingredients and 99.5% to 0.1%, especially 99% to 5%, of solid or liquid adjuvants (including, for example, solvents such as water), wherein the adjuvant can be a surfactant, in an amount of 0 to 50%, especially 0.5% to 40%, based on the premix formulation.

[0079] While commercial products will preferably be formulated as concentrates (eg, premix compositions (formulations)), the end user will typically employ a diluted formulation (eg, a tank-mix composition).

[0080] Preferred seed treatment premix formulations are aqueous suspension concentrates. Conventional processing techniques and machines can be used, such as fluidized bed technology, drum milling method, static rotation (rotostatic) seed treatment machine and drum coating machine, to apply the formulation to the seed. Other methods (such as spouted bed) can also be useful. Seeds can be pre-sized before coating. After coating, seeds are typically dried and then transferred to a sizing machine to be sized. Such procedures are known in the art. Cyclobutaflutamide is particularly suitable for use in soil and seed treatment applications.

[0081] The invention will now be illustrated by the following non-limiting examples.All references cited are incorporated by reference.

[0082] Biological Examples

[0083] Effects of nematicide treatments on Aphelenchus species.

[0084] A soybean pot trial was conducted in a greenhouse at Holambra Field Station in Sao Paulo State, Brazil, to evaluate the efficacy of nematicidal treatments against the rice stem-tipped nematode.

[0085] Seeds of the susceptible soybean variety Nidera 6828 IPRO were treated (seed treatment) at a field station with 0.6 liters of the slurry (spray solution) per 100 kg of soybean seeds. The treated seeds (treatments 3-10) were then compared to untreated controls.

[0086] Two seeds were sown in 1-liter pots with Holambra Mix (25% Holambra Workstation soil and 75% pasteurized sand). After soybean emergence, plants were selected by removing less developed potted plants; each pot had a final stand of one plant per pot for further inoculation. Nematode inoculation of each plant was carried out using a pipette 8 days after emergence (at crop stage V1), with 1000 Aphelenchus spp. larvae per plant inoculated directly into the base of the plant. One pot containing one infested soybean plant was placed in each plot of the experiment. A total of six replicates were used for each treatment. The plants were grown in separate plastic chambers in a greenhouse with an average daytime temperature of 30°C and an average nighttime temperature of 20°C (to avoid plot contamination). The plants were watered several times a day by an automatic sprinkler system (to maintain a favorable environment for nematode population growth and migration to the aboveground parts of the plants).

[0087] Nematode counts [total number of larvae per gram of aerial parts (stems + leaves)] were performed 28 days after inoculation (28 DAI).

[0088] Trial Location:

[0089]

[0090] Treatment list - greenhouse trial:

[0091]

[0092] NOTE: Treatments 2, 3, 4, 5, 6, 7, 8, 9, and 10: All received nematode inoculation (NI) Crops and targets present in the trial:

[0093] Latin name common name target Rice stem nematode - crop Glycine max(L.)Merr. soybeans

[0094] Crop Description:

[0095] Test crops Soybean-Glycine max(L.)Merr. variety Nidera 6828IPRO Sowing date January 9, 2020

[0096] Test layout:

[0097] Test environment (test method) greenhouse Experimental design Randomized complete block #repeat 6

[0098] Application details:

[0099]

[0100] Evaluate:

[0101] Nematode control (number of larvae per gram of fresh plant material), 28 days after inoculation:

[0102]

[0103]

[0104] in conclusion:

[0105] In this trial, cyclopentafen demonstrated unexpectedly superior activity against Avicta 500FS and Ilevo 600Fs against Avicta 500FS attacking soybeans when evaluated 28 days after inoculation (DPI), even at the lowest application rate tested of 5 g AI per 100 kg seed.

Claims

1. A method of controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchus, said method comprising applying the compound cytofluan to a plant crop, its locus or its propagation material.

2. The method according to claim 1, wherein The compound cyclohexane is applied as a pesticidal composition comprising cyclohexane and one or more formulation adjuvants.

3. The method according to claim 2, wherein: The pesticidal composition is a suspension composition.

4. The method according to any one of claims 1 to 3, wherein The plant parasitic nematode is the rice stem-axylonematode.

5. The method according to any one of claims 1 to 3, wherein The plant is selected from the group consisting of rice, strawberry, bean, cowpea, soybean, cotton and ornamental plant species.

6. The method according to any one of claims 1 to 3, wherein The plant is soybean or cotton.

7. The method according to any one of claims 1 to 3, wherein The plant is soybean.

8. The method according to any one of claims 1 to 3, wherein The compound cyclohexane or a pesticidal composition comprising cyclohexane is applied to the propagation material.

9. The method according to claim 8, wherein The propagation material is seeds.

10. The method according to claim 9, wherein: The compound cyclohexane is applied to the seeds in an amount between 5 and 100 grams of cyclohexane per 100 kg of seeds.

11. The method according to claim 9, wherein: The compound cyclohexane is applied to the seeds in an amount between 10 and 80 grams of cyclohexane per 100 kg of seeds.

12. The method according to claim 9, wherein The compound cyclohexane is applied to the seeds in an amount between 10 and 40 grams of cyclohexane per 100 kg of seeds.

13. Use of cyclohexane or a pesticidal composition comprising cyclohexane for controlling or preventing infestation of plants by plant-parasitic nematodes of the genus Aphelenchus.

14. The use according to claim 13, wherein The plant parasitic nematode is the rice stem-axylonematode.

15. Use according to claim 13 or 14, wherein the plant is selected from rice, strawberry, bean, cowpea, soybean, cotton and ornamental plant species.

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