A fungicidal composition for preventing and treating fusarium wilt of bitter gourd

Abstract

The present application belongs to the technical field of pesticides, and particularly relates to a fungicidal composition for preventing and treating fusarium wilt of bitter gourd. The fungicidal composition for preventing and treating fusarium wilt of bitter gourd comprises fluazinam and carvacol or flutianil as active ingredients. The fluazinam is compounded with carvacol or flutianil by using the compounding strategy. The indoor bioactivity test shows that the compound combination has a synergistic effect on fusarium wilt of bitter gourd. Compared with single components, the compound combination can improve the prevention and treatment effect on fusarium wilt of bitter gourd, thereby effectively preventing and treating fusarium wilt of bitter gourd and providing support for developing new pesticides for preventing and treating fusarium wilt of bitter gourd.

Description

Technical Field

[0001] This invention belongs to the field of pesticide technology, specifically relating to a fungicide composition for controlling wilt disease in bitter gourd. Background Technology

[0002] Bitter melon, a vine belonging to the genus *Momordica* of the Cucurbitaceae family, is a vegetable crop used for both medicinal and culinary purposes. It is widely loved for its translucent, crisp texture and rich nutritional value. However, continuous cropping of bitter melon leads to soil degradation, increasingly severe cropping obstacles, and consequently, a greater incidence of soil-borne diseases. Fusarium wilt, caused by *Fusarium oxysporum* Schl. f. sp. *momordicae*, is a serious soil-borne disease affecting both yield and quality. Its general incidence rate is 15-25%, but can reach 60% in fields with continuously cropped subspecies. During outbreaks, large numbers of withered and dead plants appear in the field, leading to reduced yields and significant economic losses.

[0003] To date, chemical pesticides remain the most effective and direct means of controlling Fusarium wilt in bitter gourd. The main chemical pesticides used in production include thiophanate-methyl, carbendazim, tebuconazole, and chlorothalonil. However, due to the rapid growth and high adaptability of the Fusarium wilt pathogen, continuous use of the same chemical pesticide can easily lead to pesticide resistance. Therefore, screening and developing new pesticides for controlling Fusarium wilt in bitter gourd is of great value.

[0004] Fluindapyr is a pyrazolamide fungicide, belonging to the succinate dehydrogenase inhibitor class. It inhibits mitochondrial function by interfering with the tricarboxylic acid cycle in respiratory electron transport complex II, preventing mitochondrial energy production, inhibiting pathogen growth, and ultimately causing pathogen death. It can be used to control a variety of plant fungal diseases.

[0005] There are currently no reports of combining fludioxonil with carvacrol or fluthiazopyrone.

[0006] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to provide a bactericidal composition for preventing and controlling wilt disease in bitter gourd, thereby solving the problem.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A fungicidal composition for controlling wilt disease in bitter gourd, wherein the active ingredient is a compound of fluopyram and carvacrol or fluthiazopyrone.

[0010] Preferably, the mass ratio of fluopyram to carvacrol is 1-10:40-1.

[0011] Preferably, the mass ratio of fluopyram to fluthiazopyr is 1-16:16-1.

[0012] More specifically, the pathogen causing the bitter gourd wilt disease is Fusarium oxysporum cucumeriforme.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] (1) The present invention adopts a compounding strategy, combining fluopyram with carvacrol or fluthiazopyrone. Indoor bioactivity tests have shown that the compound combination has a synergistic effect on the wilt pathogen of bitter gourd. Compared with the single component, it can improve the control effect of bitter gourd wilt, and thus effectively control bitter gourd wilt. It can provide support for the development of new agents for the control of bitter gourd wilt.

[0015] (2) Compared with single chemical agents, the bactericidal composition formulated by the present invention can reduce the risk of drug resistance, slow down the development of pathogens, and reduce the cost of prevention and control. Detailed Implementation

[0016] The technical solution of this invention patent will be clearly and completely described below with reference to specific embodiments.

[0017] 1. Indoor bioactivity test

[0018] 1.1 Test strains

[0019] The stem bases of bitter gourd plants infected with Fusarium wilt were collected and isolated and cultured using conventional tissue isolation methods. The pathogen was identified as Fusarium oxysporum Schl.f.sp.momordicae.

[0020] 1.2 Test reagents

[0021] 97% fludioxonil technical grade, 92.5% carvacrol technical grade, and 95% fluthiazopyr technical grade are all commercially available.

[0022] All the above-mentioned test reagents were dissolved in dimethyl sulfoxide and then diluted with 0.1% Tween-80 aqueous solution to prepare a single-agent stock solution with an active ingredient concentration of 10000 mg / L. Multiple formulations were prepared, and each single-agent stock solution and formulation mixture was further diluted with 0.1% Tween-80 aqueous solution to create five mass concentration gradients for later use.

[0023] 1.3 Test Methods

[0024] The mycelial growth rate method (Mu Liyi 1994) was used. The pesticide solution and culture medium at about 50℃ were mixed evenly in an Erlenmeyer flask at a volume ratio of 1:9. The mixture was then poured into sterile petri dishes with a diameter of 9 cm to prepare pesticide-containing plates with different masses of pesticide solution, 10 mL per plate. A 0.1% Tween-80 aqueous solution was used as a blank control. Each treatment was replicated 5 times, with 1 plate per replicate.

[0025] The tested strains were inoculated onto PDA medium and cultured at 28±1℃ for 4 days. Five-mm diameter mycelial cakes were punched along the edge of each colony using a puncher. After the medium solidified, one mycelial cake was placed in the center of each of the drug-containing plates and the blank control. The plates were then covered and incubated at 28±1℃ for 5 days. The colony diameter was measured using the cross-sectional method, and the mycelial growth inhibition rate of different treatments was calculated.

[0026]

[0027] 1.4 Data Analysis

[0028] Data statistical analysis was performed using DPS software. Linear regression was conducted with the logarithm of fungicide concentration as x and the corresponding mycelial growth inhibition rate probability value as y to calculate the toxicity EC of the agent against the pathogen. 50 The cotoxicity coefficient (CTC) was calculated using the Sun Yunpei method.

[0029]

[0030] In the above formula: ATI -- the measured toxicity index of the mixture; S -- the EC50 of the standard agent. 50 The unit is mg / L; M -- EC of the mixture 50 The unit is mg / L.

[0031] TTI = TI A ×P A +TI B ×P B

[0032] In the above formula: TTI -- theoretical toxicological index of the mixture; TI A --Toxicity index of drug A; P A --Percentage content of drug A in the mixture, expressed as a percentage (%); TI B --Toxicity index of drug B; P B --The percentage content of drug B in the mixture, expressed as a percentage (%).

[0033]

[0034] In the above formula: CTC -- co-toxicity coefficient; ATI -- measured toxicity index of the mixture; TTI -- theoretical toxicity index of the mixture.

[0035] 1.5 Results Analysis

[0036] The synergistic effect of the agent was evaluated based on the calculated co-toxicity coefficient (CTC). CTC ≤ 80 indicates antagonistic effect, 80 < CTC < 120 indicates additive effect, and CTC ≥ 120 indicates synergistic effect. The results are shown in Table 1-2.

[0037] Table 1. Indoor bioactivity assay of fluopicolide combined with carvacrol against Fusarium wilt pathogen of bitter melon.

[0038] Drug Name and Proportion <![CDATA[EC 50 (mg / L)]]> ATI TTI CTC Fluopyram 1.3527 100.0000 -- -- carvacrol 11.2479 12.0262 -- -- Fluopyram 1: Carvacrol 40 5.2270 25.8791 14.1719 182.6079 Fluopyram 1: Carvacrol 30 3.3628 40.2254 14.8641 270.6211 Fluopyram 1: Carvacrol 20 2.1114 64.0665 16.2155 395.0949 Fluopyram 1: Carvacrol 10 4.6752 28.9335 20.0239 144.4952 Fluopyram 1: Carvacrol 5 3.9206 34.5024 26.6885 129.2779 Fluinazole 1: Carvacrol 1 1.7428 77.6165 56.0131 138.5684 Fluopyram 5: Carvacrol 1 1.0372 130.4184 85.3377 152.8263 Fluopyram 10: Carvacrol 1 0.9155 147.7553 92.0024 160.5994

[0039] As shown in Table 1, the co-toxicity coefficients of fluopyram and carvacrol against Fusarium wilt pathogens of bitter gourd are all greater than 120 in the mass ratio range of 1-10:40-1, indicating a synergistic effect.

[0040] Table 2. Indoor bioactivity assay of fluopyram and fluthiazopyr combined with Fusarium wilt pathogen of bitter melon.

[0041]

[0042]

[0043] As shown in Table 2, the co-toxicity coefficients of fluopyram and fluthiazopyrone against Fusarium wilt of bitter gourd are all greater than 120 in the mass ratio range of 1-16:16-1, indicating a synergistic effect.

[0044] In summary, this invention employs a compounding strategy, combining fluopyram with carvacrol or fluthiazopyrone. Indoor bioactivity tests revealed that the compound combination exhibits a synergistic effect against Fusarium wilt pathogens of bitter gourd. Compared with single components, it can improve the control effect against Fusarium wilt of bitter gourd, thereby effectively controlling the disease and providing support for the development of novel agents for the prevention and control of Fusarium wilt of bitter gourd.

[0045] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A bactericidal composition for controlling wilt disease in bitter gourd, characterized in that, Its active ingredient is a compound of fluopyram and carvacrol, wherein the mass ratio of fluopyram to carvacrol is 1-10:40-1.

Images