Application of an amide compound in controlling plant root-knot nematodes

Abstract

The present invention discloses an application of an amide compound in preventing and treating plant root-knot nematodes. The amide compound is N ‑(2‑(5‑(1‑methyl‑1 H -pyrazol-4-yl)thiophene-2-yl)ethyl)-2-(trifluoromethyl)benzamide and / or its pesticide-acceptable salt. After testing, the amide compounds of the present invention N ‑(2‑(5‑(1‑methyl‑1 H The 24-hour LD50 of (4-(trifluoromethyl)-pyrazol-4-yl)thiophene-2-yl)ethyl)-2-(trifluoromethyl)benzamide against southern root-knot nematodes, javanic root-knot nematodes, and elephant-ear bean root-knot nematodes was 1. 50 The concentrations were 5.04μg / ml, 5.30μg / ml and 5.11μg / ml respectively; the median lethal dose LC of the southern root-knot nematode, the javanic root-knot nematode and the elephant-ear root-knot nematode was 48 hours. 50 The concentrations are 5.30μg / ml, 5.08μg / ml and 5.05μg / ml respectively. They have a strong toxic effect on plant root-knot nematodes such as southern root-knot nematode, javanic root-knot nematode and elephant-ear bean root-knot nematode, but have no toxic activity on non-plant pathogenic nematode Caenorhabditis elegans. They can be used for the prevention and control of plant root-knot nematodes.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural pest control, and particularly relates to an application of an amide compound in controlling plant root-knot nematodes. Background Art

[0002] Among common plant-parasitic nematodes, the root-knot nematodes of the genus Meloidogyne are the most detrimental to plants. The most widespread and damaging root-knot nematodes are the southern root-knot nematode (Meloidogyne incognita), the peanut root-knot nematode (Meloidogyne arenaria), the northern root-knot nematode (Meloidogyne hapla), and the Java root-knot nematode (Meloidogyne javanica). Currently, the primary method for controlling root-knot nematodes is chemical control. However, most of the currently developed chemical control agents have disadvantages such as high production costs, low efficacy, and significant environmental damage. Therefore, the development of new, low-cost, highly effective, and environmentally friendly chemical control agents has become a key focus and issue in root-knot nematode control.

[0003] Amide compounds are widely used in the research and development of nematicides and insecticides, including fluopyram, tolfenpyram, bromofenac, chlorfenapyr, thiobenzamide (3-bromo-N-[4-chloro-2-methyl-6-(methylaminothioformyl)benzene]-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide), N-(1-cyano-2-hydroxy-1-methyl-ethyl)-4-(trifluoromethylmercapto)benzamide, etc. Although amide compounds have been reported as nematicides, no studies have shown that amides can be used as nematicides. N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide ( N -(2-(5-(1- methyl-1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide) has a report on its nematicidal activity and its use in the preparation of nematicidal preparations. Summary of the Invention

[0004] The present invention aims to provide an application of an amide compound in preventing and controlling plant root-knot nematodes.

[0005] The object of the present invention is achieved in that the amide compound N -(2-(5-(1-methyl- 1 H-pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide and / or its pesticide-acceptable salt in preventing and controlling plant root-knot nematodes, and the amide compound N -(2-(5-(1-methyl- 1 H The structural formula of -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide is shown in Formula I:

[0006]

[0007] I.

[0008] The present invention first discovered N -(2-(5-(1-methyl- 1 H The invention discloses a novel (trifluoromethyl)benzamide (1-(trifluoromethyl)-1-pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide, which has a strong toxic effect against various plant root-knot nematodes and no insecticidal activity against model nematodes of non-plant pathogenic nematodes, and is characterized by high efficiency and low toxicity. The invention provides a new lead compound for the research and development of root-knot nematode pesticides, enriches the structural types of amide-based root-knot nematode pesticides, and offers new ideas and approaches for the development of new root-knot nematode preparations. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 The compound of the present invention N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide

[0010] The structural formula of

[0011] Figure 2 For the compound in Example 1 N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzene

[0012] Calculation results of amide toxicity test against southern root-knot worm;

[0013] Figure 3 for N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide

[0014] The calculation results of the toxicity determination of insects;

[0015] Figure 4 for N -(2-(5-(1-methyl- 1 H-pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide

[0016] Results of the nematode virulence assay. DETAILED DESCRIPTION

[0017] The present invention will be further described in detail below with reference to the embodiments, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention fall within the scope of protection of the present invention.

[0018] The present invention provides an amide compound N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide and / or its pesticide-acceptable salt in controlling plant root-knot nematodes, said compound N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide Figure 1 Compound N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide was purchased from MCE Company with the code number HY-Q32201.

[0019]

[0020] I.

[0021] The root-knot nematode is the southern root-knot nematode, the northern root-knot nematode, the Java root-knot nematode, the peanut root-knot nematode or the elephant-ear bean root-knot nematode.

[0022] The present invention also provides a pharmaceutical composition for preventing and treating plant root-knot nematodes, wherein the pharmaceutical composition comprises a compound N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide and / or its pesticide-acceptable salt is the main active ingredient or one of the active ingredients.

[0023] The present invention further provides a plant root-knot nematode insecticide based on the pharmaceutical composition, wherein the insecticide is in the form of an aqueous solution, an aqueous emulsion, a wettable powder, a soluble powder, a soluble granule, a water-dispersible granule, a suspension, an oil suspension, a tablet or an effervescent granule.

[0024] The aqueous solution or aqueous emulsion N -(2-(5-(1-methyl- 1 HThe mass concentration of the 2-(trifluoromethyl)benzamide is 1-50 μg / ml, and the solvent is a fatty alcohol aqueous solution or a dimethyl sulfoxide aqueous solution with a concentration of ≤10%.

[0025] The fatty alcohols include but are not limited to methanol, ethanol and propanol.

[0026] Example 1 N -(2-(5-(1-methyl- 1 H Nematicidal activity assay of 2-(trifluoromethyl)benzamide

[0027] 1. Sample preparation

[0028] 0.5mg-1.5mg N -(2-(5-(1-methyl- 1 H (-Pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide was dissolved in DMSO and diluted with 4% DMSO to serve as test solutions. The concentrations of each dilution were 0.03 μg / ml, 0.05 μg / ml, 0.1 μg / ml, 0.3 μg / ml, 0.5 μg / ml, 1 μg / ml, 3 μg / ml, 5 μg / ml, 10 μg / ml, 30 μg / ml, and 50 μg / ml, respectively. The DMSO concentration in each solution was 0.4%. Water containing 0.4% DMSO served as a blank control.

[0029] 2. Preparation of Nematodes for Experimental Use

[0030] Tomato roots infected with the southern root-knot nematode were washed with water. Oocysts were picked with a dissecting needle and placed in a 0.4 M KCl solution. In a 5 ml centrifuge tube, the roots were washed and disinfected three times with 4 ml of sterile water, 1 ml of sterile penicillin-streptomycin solution, and 3 ml of 0.1% NaClO solution. The supernatant was removed by brief centrifugation at each step (8000 rpm for 30 seconds). The washed eggs were incubated in a 0.4 M ZnCl₂ solution for 48 hours. Second-instar larvae were collected with a pipette into a 1.5 ml centrifuge tube and enriched by brief centrifugation at 5000 rpm for 30 seconds.

[0031] In addition, this experiment also prepared experimental nematodes such as Java root-knot nematode, elephant ear bean root-knot nematode and Caenorhabditis elegans according to conventional methods.

[0032] 3. Test methods

[0033] Transfer 100 μl of each test solution prepared in step 1 to a 20-well plate. Add 50-100 live nematodes prepared in step 2. Incubate at 25°C and calculate nematode mortality under a light microscope after 24, 48, and 72 hours. Identify nematode mortality by adding 1-5 drops of 5% NaCl solution to the treated wells. After 2 minutes, observe. Dead nematodes will be rigid and unresponsive to needle stimulation. Live nematodes will curl or twist.

[0034] The test solution without sample was used as the control, and the whole experiment was repeated three times. The average of the three times was taken to calculate the corrected mortality rate.

[0035] Mortality % = (number of dead nematodes / (number of dead nematodes + number of surviving nematodes)) × 100%

[0036] Corrected mortality % = sample mortality – control mortality

[0037] 4. Experimental results

[0038] 4.1 N -(2-(5-(1-methyl- 1 H The toxicity of 2-(trifluoromethyl)benzamide to southern root-knot nematodes is shown in Table 1 and Figure 2 As shown:

[0039] Table 1 N -(2-(5-(1-methyl- 1 H Toxic effects of 2-(trifluoromethyl)benzamide on southern root-knot nematodes

[0040]

[0041] 4.2 N -(2-(5-(1-methyl- 1 H The toxicity of 2-(trifluoromethyl)benzamide to root-knot nematodes is shown in Table 2 and Table 3. Figure 3 shown.

[0042] Table 2 N -(2-(5-(1-methyl- 1 H Toxic effects of 2-(trifluoromethyl)benzamide on root-knot nematodes of Javanese

[0043]

[0044] 4.3 N -(2-(5-(1-methyl- 1 HThe toxicity of 2-(trifluoromethyl)-1-pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide to root knot nematodes of ear bean is shown in Table 3 and Figure 4 As shown:

[0045] Table 3 N -(2-(5-(1-methyl- 1 H The toxicity of 2-(trifluoromethyl)benzamide to root-knot nematodes of ear bean

[0046]

[0047] 4.4 N -(2-(5-(1-methyl- 1 H 1-pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide had no toxic activity against the non-plant pathogenic nematode Caenorhabditis elegans at 24 hours.

[0048] Result analysis: After determination ( Figure 2-4 ), N -(2-(5-(1-methyl- 1 H The LC50 of (-pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide against southern root-knot nematodes, javanic root-knot nematodes and elephant-ear bean root-knot nematodes in 24 hours 50 The concentrations were 5.04 μg / ml, 5.30 μg / ml and 5.11 μg / ml respectively; the median lethal dose LC of the southern root-knot nematode, the javanic root-knot nematode and the elephant-ear root-knot nematode was 48 hours. 50 The concentrations are 5.30 μg / ml, 5.08 μg / ml and 5.05 μg / ml respectively. They have a strong toxic effect on plant root-knot nematodes such as southern root-knot nematode, javanic root-knot nematode and elephant-ear bean root-knot nematode, but have no toxic activity on non-plant pathogenic nematode Caenorhabditis elegans. They can be used for the prevention and control of plant root-knot nematodes.

[0049] Example 2

[0050] An insecticide for controlling plant root knot nematodes, the insecticide uses a 3% DMSO aqueous solution as a solvent and a concentration of 20 μg / ml N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide is the active ingredient.

[0051] Example 3

[0052] An insecticide for controlling plant root knot nematodes, the insecticide uses a 7% ethanol solution as a solvent and a concentration of 30 μg / ml N-(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide is the active ingredient.

[0053] Example 4

[0054] An insecticide for controlling plant root knot nematodes, the insecticide is prepared by using a 3% methanol aqueous solution as a solvent and a concentration of 10 μg / ml. N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide is the active ingredient.

[0055] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. Amide compounds N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide and / or its pesticide acceptable salt in controlling plant root knot nematodes, characterized in that: The compound N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide structural formula is shown in Formula I: I； N -(2-(5-(1-methyl- 1 H The mass concentration of the 2-(trifluoromethyl)benzamide is 1-50 μg / ml.

2. The application according to claim 1, characterized in that The root-knot nematode is the southern root-knot nematode, the Java root-knot nematode or the elephant-ear bean root-knot nematode.

3. A pharmaceutical composition for controlling plant root-knot nematodes, characterized in that: The pharmaceutical composition for preventing and treating plant root-knot nematodes is composed of a compound N -(2-(5-(1-methyl- 1 H -pyrazol-4-yl)thiophen-2-yl)ethyl)-2-(trifluoromethyl)benzamide and / or its pesticide-acceptable salt is an active ingredient, N -(2-(5-(1-methyl- 1 H The mass concentration of the 2-(trifluoromethyl)benzamide is 1-50 μg / ml, and the solvent is a fatty alcohol aqueous solution or a dimethyl sulfoxide aqueous solution with a concentration of ≤10%.

4. A plant root-knot nematode insecticide based on the pharmaceutical composition of claim 3, characterized in that: The dosage form of the insecticide is aqueous solution, aqueous emulsion, wettable powder, soluble powder, soluble granule, water-dispersible granule, suspension, oil suspension, tablet or effervescent granule.

5. The pharmaceutical composition for controlling plant root-knot nematodes according to claim 3, characterized in that The fatty alcohol is methanol, ethanol or propanol.

Images