A composition containing plant extracts and its application

Abstract

The present invention belongs to the technical field of pesticides and discloses a composition containing plant extracts and its application. The effective components of the composition containing plant extracts provided by the present invention are composed of oregano extract and stemona extract, and the mass ratio of oregano extract to stemona extract is 1:8 to 4:1. Within the ratio range provided by the present invention, the composition containing plant extracts has a good inhibitory effect on the gray mold pathogen Botrytis cinerea, and has a synergistic effect on the inhibitory effect on Botrytis cinerea. Within the ratio range provided by the present invention, the composition containing plant extracts has a good preventive effect on tomato gray mold, and its preventive effect is 77.4% to 93.6%. The present invention provides a high-efficiency, low-toxicity, low-pollution biological pesticide for the prevention and control of gray mold.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticides and relates to a composition containing plant extracts and application thereof. Background Art

[0002] Gray mold is a fungal disease caused by Botrytis cinerea Pers., which can lead to reduced crop yield and quality. It can infect a variety of plants, including tomatoes, strawberries, grapes, and roses, affecting flowers, fruit, leaves, and stems. Botrytis cinerea thrives in high humidity and relatively low temperatures. The pathogen persists as hyphae or conidia on diseased stems and leaves, and can also survive on the ground as highly resistant sclerotia. When temperatures reach 15-20°C and humidity is high, conidia form and disperse, typically invading petals, weakened leaves, and wounds. Lesions form two to three days after invasion, and countless conidia form again, infecting surrounding plants. Infected plant tissue initially appears as water-soaked spots, which then develop into brown lesions covered with a gray mold layer, giving the appearance of water rot.

[0003] Existing technologies for the prevention and control of gray mold mainly include agricultural control and chemical control. Agricultural control includes: seed ozone sterilization, high-dose ozone sterilization in greenhouses, breeding of disease-resistant varieties, reasonable close planting, clean fields, reducing greenhouse humidity, variable temperature ventilation, and removing residual petals and stigmas. However, agricultural control has problems such as long cycle time, high cost, and difficulty in environmental control. Chemical control includes the use of chemical agents such as procymidone, methyl thiophanate, iprodione, pyrimethanil, and pyrimidine-thiram. However, the long-term application of chemical agents can easily lead to the development of drug resistance in gray mold pathogens, resulting in reduced control effectiveness. Excessive use of chemical agents can also lead to pesticide residues and environmental pollution. Therefore, the development of a highly effective, low-toxic, and low-pollution biopesticide is of great significance.

[0004] Oregano extract, extracted from the oregano plant, is a botanical fungicide. Oregano extract contains active ingredients such as carvacrol and thymol, which have been shown to have strong antimicrobial activity. These active ingredients are highly surface active and lipid-soluble, allowing them to quickly penetrate the cell membranes of pathogens, causing water imbalance and their death. Oregano extract is used in agriculture to prevent and control diseases such as rice blast, rust, gray mold, and powdery mildew.

[0005] Stemona extract is an active ingredient extracted from the dried rhizomes of Stemona erecta, Stemona serrata, or Stemona truncatula, all members of the Stemonaceae family. It exhibits multiple biological activities. Key benefits include: reducing the excitability of the respiratory center in animals and suppressing the cough reflex; exhibiting in vitro antibacterial effects against pathogens such as pneumococcus and Staphylococcus aureus; killing body and pubic lice; and having a limited preventive and therapeutic effect against influenza viruses. Stemona extract is also used in agriculture, demonstrating effective control against common diseases such as anthrax and powdery mildew, significantly inhibiting the germination of spores of the black spot pathogen of cabbage, and possessing insecticidal properties. The bioactive components in Stemona extract can interfere with DNA replication and protein synthesis in microorganisms, thereby inhibiting their growth.

[0006] At present, there are no reports on the combination of oregano extract and Stemona extract. Summary of the Invention

[0007] To address the above technical problems, the present invention provides a composition containing plant extracts and its use. The active ingredients are composed of oregano extract and Stemona extract, with the mass ratio of oregano extract to Stemona extract being 1:8 to 4:1. This plant extract-containing composition exhibits a strong inhibitory effect against Botrytis cinerea, the pathogen of gray mold. Within the mass ratio range provided by the present invention, the composition exhibits a synergistic inhibitory effect against Botrytis cinerea. The plant extract-containing composition of the present invention exhibits a strong control effect against gray mold in tomatoes. This present invention provides a highly effective, low-toxic, and low-pollution biopesticide for controlling gray mold.

[0008] To achieve the technical purpose of the present invention, on the one hand, the present invention provides a composition containing plant extracts, the active ingredients of which are composed of oregano extract and Stemona extract, and the mass ratio of oregano extract to Stemona extract is 1:8 to 4:1; preferably, the mass ratio of oregano extract to Stemona extract in the composition containing plant extracts is 1:1.

[0009] On the other hand, the present invention claims use of the composition containing the plant extract in inhibiting Botrytis cinerea.

[0010] Furthermore, the present invention found through indoor toxicity test that when the mass ratio of the composition containing plant extracts is 1:8 to 4:1, the inhibitory effect on Botrytis cinerea is better and has a synergistic effect. When the mass ratio of oregano extract and Stemona extract is in the range of 1:8 to 16:1, it has a good inhibitory effect on the mycelial growth of Botrytis cinerea, and its EC 50实际The value is 0.25-0.84; when the mass ratio of oregano extract and Stemona extract is in the range of 1:8-4:1, the two plant extracts have a synergistic effect, and the SR is greater than 1.5; especially when the mass ratio of oregano extract and Stemona extract is 1:1, the synergistic effect is optimal, and the SR is 3.60.

[0011] On the other hand, the present invention claims protection for the use of the above-mentioned composition containing plant extracts in preventing and controlling gray mold, the pathogen of gray mold is Botrytis cinerea Pers., and the gray mold includes tomato gray mold.

[0012] Furthermore, the present invention has learned through field trials that within the ratio range of oregano extract and Stemona extract provided by the present invention, the composition has a good effect on preventing and controlling tomato gray mold, and the prevention and control effect is significantly better than any single agent. When the ratio range provided by this application is exceeded, the prevention and control effect deteriorates. When the mass ratio of oregano extract and Stemona extract is in the range of 1:8 to 4:1, the prevention and control effect on tomato gray mold caused by Botrytis cinerea is 77.4% to 93.6%; when oregano extract or Stemona extract is used alone, the prevention and control effect on tomato gray mold is about 60%; when the mass ratio range provided by the present invention is exceeded, the prevention and control effect of the composition on tomato gray mold is 62.1% and 63.5%.

[0013] In addition, the present invention seeks to protect a method for preventing and controlling tomato gray mold, using the above-mentioned composition containing plant extracts, wherein the amount of active ingredient of the composition containing plant extracts is 5g / mu.

[0014] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects or advantages:

[0015] The present invention provides a composition containing plant extracts, wherein the active ingredients are oregano extract and stemona extract, and the mass ratio of oregano extract to stemona extract is 1:8 to 4:1. The composition has a better inhibitory effect on Botrytis cinerea and has a synergistic effect. The present invention found through indoor toxicity testing that when the mass ratio of oregano extract to stemona extract is in the range of 1:8 to 16:1, it has a better inhibitory effect on the mycelial growth of Botrytis cinerea. Its EC 50实际 The value is 0.25-0.84; when the mass ratio of oregano extract and Stemona extract is in the range of 1:8-4:1, the two plant extracts have a synergistic effect, and the SR is greater than 1.5; especially when the mass ratio of oregano extract and Stemona extract is 1:1, the synergistic effect is optimal, and the SR is 3.60.

[0016] The composition containing plant extracts provided by the present invention can prevent and control gray mold caused by Botrytis cinerea. The present invention has learned through field tests that within the ratio range of oregano extract and Stemona extract provided by the present invention, the composition has a good effect of preventing and controlling tomato gray mold, and the prevention and control effect is significantly better than any single agent. When the ratio range provided by this application is exceeded, the prevention and control effect becomes worse. When the mass ratio range of oregano extract and Stemona extract is 1:8 to 4:1, the prevention and control effect on tomato gray mold caused by Botrytis cinerea is 77.4 to 93.6%; when oregano extract or Stemona extract is used alone, the prevention and control effect on tomato gray mold is about 60%; when the mass ratio range provided by the present invention is exceeded, the prevention and control effect of the composition on tomato gray mold is 62.1% and 63.5%.

[0017] The two active ingredients in the composition of the present invention are both botanical pesticides, which are derived from nature, do not pollute the environment and agricultural products, are relatively safe for livestock, are not prone to drug resistance, and have good application prospects in preventing and controlling gray mold caused by Botrytis cinerea. DETAILED DESCRIPTION

[0018] The following examples illustrate the technical solutions of the present invention, but the present invention is not limited to the following examples. The experimental methods and detection methods described in each example are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0019] Preparation of Oregano Extract: Oregano herb was purchased from Jiangsu Fuchun Garden Co., Ltd. A certain amount of dried whole oregano herb was weighed and pulverized. Six times its weight of purified water was added and ultrasonicated at 500W for 20 minutes. The extract was heated and distilled using a volatile oil extractor. The supernatant oil was collected and the volatile oil was extracted with redistilled ether. The supernatant oil was placed in a stoppered test tube, dehydrated with anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure until the ether odor disappeared. This yielded the oregano extract. The main components of the oregano extract are carvacrol, thymol, thymol, and terpinene.

[0020] Preparation of Stemona Radix Extract: Stemona Radix (Stemona erecta root) was purchased from Bozhou Chenghui Pharmaceutical Sales Co., Ltd. A certain amount of dried Stemona erecta root tubers was weighed and crushed. Refluxing extraction was performed with 10 times the weight of 80% ethanol to obtain an ethanol extract. The ethanol extract was dissolved in water, and the pH was adjusted to 3 with concentrated hydrochloric acid. The extract was filtered, and the filtrate was again adjusted to pH 9 with aqueous sodium hydroxide. The extract was then extracted with redistilled ether. The upper oil phase was removed from the water with anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure until the ether odor disappeared. This yielded the Stemona Radix Extract. The main components of the Stemona Radix Extract are: erect stemone, hopolinine, scutellarine, and prostemonine.

[0021] Example 1

[0022] This example provides a formulation of the composition.

[0023] Test 1: 1.8% oregano extract and stemona extract soluble solution

[0024] Calculated by mass percentage: oregano extract 0.2%, stemona extract 1.6%, polyoxyethylene fatty alcohol ether 1%, alkyl glycoside 2%, acetone 3%, dimethylformamide is supplemented to 100%.

[0025] Test 2: 1% oregano extract and stemona extract soluble solution

[0026] Calculated by mass percentage: oregano extract 0.5%, stemona extract 0.5%, polyoxyethylene fatty alcohol ether 1%, alkyl glycoside 1%, acetone 2%, dimethylformamide is supplemented to 100%.

[0027] Test 3, 5% oregano extract and stemona extract soluble solution

[0028] Calculated by mass percentage: oregano extract 4%, stemona extract 1%, polyoxyethylene fatty alcohol ether 3%, alkyl glycoside 3%, acetone 6%, dimethylformamide is supplemented to 100%.

[0029] Test 4: 3% oregano extract and stemona extract soluble solution

[0030] Calculated by mass percentage, the invention comprises: 0.6% of oregano extract, 2.4% of stemona extract, 2% of polyoxyethylene fatty alcohol ether, 2% of alkyl glycoside, 4% of acetone, and dimethylformamide supplemented to 100%.

[0031] Test 5: 1.5% oregano extract and stemona extract soluble solution

[0032] Calculated by mass percentage: oregano extract 1%, stemona extract 0.5%, polyoxyethylene fatty alcohol ether 1%, alkyl glycoside 2%, acetone 2%, dimethylformamide is supplemented to 100%.

[0033] Test 6, 2.4% oregano extract and stemona extract soluble solution

[0034] Calculated by mass percentage: oregano extract 0.8%, stemona extract 1.6%, polyoxyethylene fatty alcohol ether 1%, alkyl glycoside 2%, acetone 3%, dimethylformamide is supplemented to 100%.

[0035] Comparison 1: 3.4% oregano extract and stemona extract soluble solution

[0036] Calculated by mass percentage: oregano extract 0.2%, stemona extract 3.2%, polyoxyethylene fatty alcohol ether 2%, alkyl glycoside 2%, acetone 4%, dimethylformamide is supplemented to 100%.

[0037] Comparison 2: 4.5% oregano extract and stemona extract soluble solution

[0038] Calculated by mass percentage: oregano extract 4.0%, stemona extract 0.5%, polyoxyethylene fatty alcohol ether 3%, alkyl glycoside 2%, acetone 5%, dimethylformamide is supplemented to 100%.

[0039] Comparison of 3% and 4% oregano extract soluble solutions

[0040] Calculated by mass percentage: oregano extract 4.0%, polyoxyethylene fatty alcohol ether 3%, alkyl glycoside 2%, acetone 5%, and dimethylformamide is supplemented to 100%.

[0041] Comparison 4, 0.5% Stemona extract soluble solution

[0042] Calculated by mass percentage: 0.5% of Stemona extract, 1% of polyoxyethylene fatty alcohol ether, 1% of alkyl glycoside, 2% of acetone, and dimethylformamide to make up to 100%.

[0043] Example 2

[0044] This example provides an in-house toxicity assay of the composition.

[0045] The test agents oregano extract and stemona extract were dissolved in ethanol, respectively, and then diluted with 0.1% Tween-80 aqueous solution to prepare single-dose stock solutions and mixed stock solutions with different mass ratios (1:16, 1:8, 1:4, 1:2, 1:1, 2:1, 4:1, 8:1, 16:1). Five mass concentration gradients were set for each single agent and mixture according to the equal ratio method.

[0046] The toxicity of each single agent and mixture against Botrytis cinerea (collected from tomato plants exhibiting gray mold in a greenhouse in Yunyang Town, Jingyang County, Shaanxi Province, isolated and purified in the laboratory, and identified as the pathogen, Botrytis cinerea Pers., and stored on PDA medium) was determined using the hyphal growth rate method. The synergistic effect of the combination was evaluated using the Wadley method. A 0.5 cm section of the Botrytis cinerea cake cultured on PDA medium was cut with a hole punch and aseptically inoculated, hyphae facing down, onto the center of a solidified Petri dish (R = 9 cm) containing 14 mL of PDA medium and 1 mL of the agent (single agent or mixture) solution. A blank control containing no agent was used. Each group was replicated three times. The inoculated culture dish was placed under the conditions of temperature 23±1℃, relative humidity 80%, 12h alternating light and dark (light intensity 6000Lux) and cultured. When the diameter of the colony in the control group grew to be larger than 2 / 3 of the diameter of the culture dish, the diameter of the colony in each treatment was measured by the cross method, and the mycelial growth inhibition rate of different treatments was calculated. The logarithm of the concentration of the drug was used as the horizontal axis, and the mycelial growth inhibition rate was used as the vertical axis. The experimental data were analyzed by regression analysis to calculate the effective inhibition concentration (EC) of each treatment. 50 ), and the expected effective inhibitory concentration (EC 50exp ) and the synergistic coefficient (SR), the calculation formula is as follows, and the calculation results are shown in Table 1.

[0047] Mycelial growth inhibition rate (%) = [(colony diameter of control group - colony diameter of treated group) × 100 / (colony diameter of control group - diameter of fungus cake)];

[0048] EC 50exp =(a+b) / [(a / EC 50a )+(b / EC 50b )];

[0049] SR=EC 50exp / EC 50实际 ;

[0050] In the formula, a is the percentage of oregano extract in the mixture, b is the percentage of Stemona extract in the mixture, EC 50a is the effective inhibitory concentration of oregano extract (a) when used alone, EC 50b The effective inhibitory concentration of Stemona extract (b) when used alone. SR ≥ 1.5 indicates synergistic effect, SR ≤ 0.5 indicates antagonistic effect, and 0.5 < SR < 1.5 indicates additive effect.

[0051] Table 1: Inhibitory effect of the composition on the mycelial growth of Botrytis cinerea

[0052] Pharmacy Ratio <![CDATA[EC 50实际 / (g / L)]]> <![CDATA[EC 50exp / (g / L)]]> SR Oregano extract / 0.57 / / Stemona extract / 2.14 / / Oregano Extract: Stemona Extract 1:16 1.36 1.84 1.35 Oregano Extract: Stemona Extract 1:8 0.84 1.64 1.95 Oregano Extract: Stemona Extract 1:4 0.54 1.38 2.56 Oregano Extract: Stemona Extract 1:2 0.36 1.12 3.11 Oregano Extract: Stemona Extract 1:1 0.25 0.90 3.60 Oregano Extract: Stemona Extract 2:1 0.31 0.75 2.42 Oregano Extract: Stemona Extract 4:1 0.40 0.67 1.68 Oregano Extract: Stemona Extract 8:1 0.49 0.62 1.27 Oregano Extract: Stemona Extract 16:1 0.57 0.60 1.05

[0053] As shown in Table 1, the EC values ​​of oregano extract and Stemona extract used alone against Botrytis cinerea 50 The values ​​were 0.57 g / L and 2.14 g / L respectively. The combination of the two can improve the inhibitory effect of the composition on Botrytis cinerea. When the mass ratio of oregano extract and Stemona extract is 1:8 to 16:1, it has a good inhibitory effect on the growth of Botrytis cinerea hyphae. Its EC 50实际 The value is 0.25-0.84; when the mass ratio of oregano extract and Stemona extract is in the range of 1:8-4:1, the two plant extracts have a synergistic effect, and the SR is greater than 1.5; especially when the mass ratio of oregano extract and Stemona extract is 1:1, the synergistic effect is optimal, and the SR is 3.60.

[0054] Example 3

[0055] This example provides a field control efficacy test of the composition.

[0056] The aqueous solutions of Tests 1 to 6 and Comparative Examples 1 to 4 in Example 1 were diluted with clean water and then sprayed on the stems and leaves. The active ingredient dosage of each treatment group was 5 g / mu. The test site was a tomato greenhouse in Yunyang Town, Jingyang County, Shaanxi Province. The tomato variety tested was Provence. The plot test method was used, and the plot area of ​​each treatment group was 20 m 2 The treatments were arranged in randomized blocks and replicated three times. Applications were initiated at the early stage of tomato gray mold and repeated 5 days later. The disease grade of the leaves was assessed before the first spray and 7 days after the second application. The disease index and control efficacy of the different treatment groups were calculated using the following formula. The statistical results are shown in Table 2. The disease grading standard is:

[0057] Level 0: no lesions;

[0058] Level 1: There are 1 to 3 lesions on a single leaf;

[0059] Level 3: 4 to 6 lesions on a single leaf;

[0060] Level 5: There are 7 to 10 lesions on a single leaf;

[0061] Level 7: There are 11 to 20 lesions on a single leaf;

[0062] Level 9: Single leaves have dense spots covering more than a quarter of the leaf area.

[0063] Disease index = [Σ(number of diseased leaves at each level × relative disease level value) / (total number of leaves surveyed × highest disease level value)] × 100;

[0064] Control effect (%) = [1-(disease index of blank control before application × disease index of drug treatment after application / disease index of blank control after application × disease index of drug treatment before application)] × 100.

[0065] Table 2: Control effect of the composition on tomato gray mold

[0066]

[0067]

[0068] As shown in Table 2, when the mass ratio of oregano extract to Stemona extract is in the range of 1:8 to 4:1, the control effect on tomato gray mold caused by Botrytis cinerea is 77.4% to 93.6%. When oregano extract or Stemona extract is used alone, the control effect on tomato gray mold is about 60%. When the mass ratio range provided by the present invention is exceeded, the control effect of the combination on tomato gray mold is 62.1% and 63.5%. The above results show that within the ratio range of oregano extract to Stemona extract provided by the present invention, the combination has a good control effect on tomato gray mold, and the control effect is significantly better than any single agent. When the ratio range provided by the present application is exceeded, the control effect deteriorates.

[0069] The embodiments described above are some of the embodiments of the present invention, rather than all of them. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments obtained without creative effort and through deduction and substitution by a person of ordinary skill in the art based on the concept of the present invention are within the scope of protection of the present invention.

Claims

1. A composition containing a plant extract, characterized in that The active ingredients are composed of oregano extract and Stemona extract; The mass ratio of oregano extract to Stemona extract in the composition containing plant extracts is 1:8 to 4:1; Preparation of the oregano extract: oregano herb was purchased from Jiangsu Fuchun Garden Co., Ltd., a certain amount of dried oregano whole herb was weighed and crushed, 6 times its weight of purified water was added, and ultrasonic treatment was performed at 500W for 20 minutes. The extract was heated and distilled using a volatile oil extractor, and the upper oily substance was collected. The volatile oil was extracted with redistilled ether, and the upper oil phase was taken into a stoppered test tube, and the water was removed with anhydrous sodium sulfate. The extract was filtered, and the filtrate was concentrated under reduced pressure until there was no ether smell, thereby obtaining the oregano extract; Preparation of the Stemona extract: The roots of Stemona erecta are purchased from Bozhou Chenghui Pharmaceutical Sales Co., Ltd., a certain amount of dried tubers of Stemona erecta are weighed and crushed, 10 times the weight of 80% ethanol is added and refluxed to obtain an ethanol extract, the ethanol extract is dissolved in water, and then the pH value is adjusted to 3 with concentrated hydrochloric acid, filtered, and the filtrate is again adjusted to pH 9 with an aqueous sodium hydroxide solution, and then extracted with redistilled ether, the upper oil phase is taken to remove moisture with anhydrous sodium sulfate, filtered, and the filtrate is concentrated under reduced pressure until there is no ether smell, thereby obtaining the Stemona extract.

2. The composition containing plant extract according to claim 1, characterized in that The mass ratio of the oregano extract to the stemona extract in the composition containing plant extracts is 1:

1.

3. Use of the composition containing the plant extract according to any one of claims 1 to 2 in inhibiting Botrytis cinerea.

4. Use of the composition containing plant extracts according to any one of claims 1 to 2 in preventing and treating gray mold, characterized in that: The pathogen of gray mold is Botrytis cinerea Pers.

5. The use according to claim 4, characterized in that The gray mold disease includes tomato gray mold disease.

6. A method for preventing and controlling tomato gray mold, characterized in that: Use of the plant extract-containing composition according to any one of claims 1 to 2.

7. The method for preventing and controlling tomato gray mold according to claim 6, characterized in that: The dosage of the active ingredient of the composition containing the plant extract is 5g / mu.

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