Use of a bactericidal composition containing cephalosporin and plant essential oil in preventing and controlling plant pathogenic fungi

Abstract

The invention belongs to the field of natural drug chemistry, and discloses a composition containing leucanthemum alkaloids and plant essential oils (oregano essential oil, patchouli essential oil, cinnamon essential oil, litsea cubeba essential oil, clove essential oil, thyme essential oil, geranium essential oil, garlic essential oil, tea tree oil, calamus oil, lemongrass essential oil, clove basil oil, zedoary turmeric oil, West Indian sandalwood oil, violet essential oil). The composition is used in preventing and treating diseases caused by Rhizoctonia solani, Sclerotinia sclerotiorum of rape, fusarium head blight of wheat, gray mold of tomato, and rice blast, and the mass ratio of leucanthemum alkaloids to the plant essential oils is 1:10 and 1:20. The bactericidal composition described in the present invention has the advantages of a wide bactericidal spectrum, low toxicity, and reduced plant drug resistance, and has the value of further research and development.

Description

Technical Field

[0001] The invention belongs to the field of natural drug chemistry and relates to a bactericidal composition containing two effective ingredients, cephalosporin and plant essential oil. The composition is used for preventing and treating diseases caused by plant pathogenic fungi such as Rhizoctonia solani, Sclerotinia sclerotiorum of rape, Botrytis cinerea of ​​tomato, Gibberella fusarium of wheat, Fusarium wilt of cotton and Magnaporthe oryzae. Background Art

[0002] Plant pathogenic fungi refer to those fungi that can parasitize on plants and cause plant diseases. Diseases caused by plant pathogenic fungi account for about 70-80% of plant diseases and insect pests. Agricultural diseases caused by plant pathogenic fungi are characterized by many types, great impact and frequent outbreaks. The scope and severity of their occurrence have caused very significant losses to my country's national economy and agricultural production. The use of chemical reagents is still the main means of preventing and controlling plant fungal diseases. However, with the widespread use of fungicides, resistance, resurgence and residue are currently recognized worldwide as problems that need to be solved urgently. Combination therapy has the advantages of reducing the amount of chemical fungicides, expanding the fungicide spectrum, reducing toxicity and reducing the emergence of resistance, and has therefore become one of the important means to solve these problems.

[0003] Fructus sphenantheraceae is mainly derived from Cryptolepis sanguinolenta, a traditional medicinal plant in West Africa, and has a wide range of biological activities, including antimalarial, antibacterial and anti-tumor. In the early stage of activity screening, it was found that its main secondary metabolite, Fructus sphenantheraceae, has potential activity in resisting plant pathogens and has application prospects.

[0004] Essential oils are volatile aromatic substances extracted from the flowers, leaves, stems, roots or fruits of aromatic plants. The composition of essential oils is complex and varied, and can be composed of dozens to hundreds of different components. The content of the components is affected by many factors such as plant varieties, growth environment, extraction site, extraction method, etc. The main components are organic substances such as terpenes, phenols, aldehydes, alcohols and esters. Essential oils have biological activities such as antibacterial and anti-inflammatory. The antibacterial effect of essential oils seems to be the result of the synergistic effect of different components. It has multiple inhibitory mechanisms against pathogens, so it is not easy to develop resistance. In addition to using essential oils alone for bactericidal activity research, many essential oils are used in combination with chemical fungicides. Essid R et al. found that the combination of cinnamon essential oil (Cinnamomum verum) and amphotericin B can improve the antibacterial effect against Candida albicans. However, there are no reports on the combined use of leucoderma and plant essential oils against plant pathogenic fungi. Based on this, this study investigates the use of a composition of leucoderma as the main agent and plant essential oils as the auxiliary agent in the prevention and treatment of diseases caused by plant pathogenic fungi such as Rhizoctonia solani, Sclerotinia sclerotiorum, Botrytis cinerea, Gibberella fusca, and Magnaporthe oryzae. Summary of the invention

[0005] The purpose of the present invention is to provide a fungicide composition containing cephalosporin and plant essential oil for preventing and controlling plant pathogenic fungi in view of the defects of the prior art, and the fungicide composition is used for preventing and controlling plant diseases caused by Rhizoctonia solani, Sclerotinia sclerotiorum, Botrytis cinerea, Gibberella fusca and Magnaporthe oryzae.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] A fungicide composition containing cephalaenopsis and plant essential oil comprises an active component A and an active component B, wherein the active component A is cephalaenopsis, the active component B is the plant essential oil, and the weight ratio of the active component A to the active component B is 1:10 or 1:20.

[0008] The fungicide composition provided by the present invention has the following advantages as an agricultural fungicide:

[0009] 1) The fungicide composition provided by the present invention can reduce the dosage of the main agent component and reduce the cost of pesticides.

[0010] 2) The bactericidal composition provided by the present invention improves the control effect, expands the bactericidal spectrum, and has a relatively obvious synergistic effect under a certain compound ratio.

[0011] 3) The active ingredients in the fungicidal composition provided by the present invention have different mechanisms of action, which can effectively reduce the emergence of disease resistance in crops and enhance the control effect. DETAILED DESCRIPTION

[0012] In order to better understand the essence of the present invention, it is further described by the following specific embodiments, but the present invention is not limited to these embodiments. In these embodiments, unless otherwise specified, all percentages are weight percentages.

[0013] Example 1: A fungicide composition containing cephalaenopsis and plant essential oil, comprising an active component A and an active component B (as shown in structural formula 1), wherein the active component A is cephalaenopsis, and the active component B is plant essential oil.

[0014]

[0015] Example 2: Indoor antibacterial activity determination and results of plant pathogenic fungi

[0016] The plant pathogenic fungi used in this experiment were strains stored at 4°C in the laboratory. The mycelium growth method was used, and all plant pathogenic fungi in the laboratory were grown on potato agar glucose medium (PDA for short). PDA medium formula: 200g potato (peeled), 20g glucose, 15g agar, 1000mL distilled water, natural pH.

[0017] Preparation method of PDA culture medium: Wash and peel the potatoes, weigh 200g, cut into small pieces, add water and cook until soft (boil for 20-30 minutes, until it can be pierced by a glass rod), filter with four layers of gauze and add water to a beaker to make up to 1000mL, add 15-20g agar according to experimental needs, add 20g glucose, stir to fully dissolve, and then divide into Erlenmeyer flasks, sterilize at 121℃ for 20 minutes, and set aside after cooling.

[0018] Experimental methods

[0019] 1) Mycelial growth rate method was used.

[0020] 1. First, activate the plant pathogens by culturing them on PDA plates at 25°C for 3 to 6 days.

[0021] 2. Heat and melt the PDA culture medium, cool it to 45-50°C, and add different concentrations of bactericidal compositions to prepare drug-coated plates.

[0022] 3. Using aseptic operation procedures, use a cork puncher to make a round cake (5mm in diameter) at the edge of the hyphae of each strain cultured for 3 to 6 days (the growth conditions should be as consistent as possible), then use an inoculation needle to pick it to the center of the drug-containing plate, and then place the culture dish upside down in an incubator (25℃) for culture.

[0023] 4. After the blank control group is fully grown, observe and measure the growth of mycelium, and use the cross method to measure the diameter and process the data to calculate the inhibition rate.

[0024] 5. Inhibition rate (%) = (control mycelium diameter - treated mycelium diameter) / (control mycelium diameter - cake diameter) × 100

[0025] 6. Each treatment was repeated 3 times.

[0026] 7. The results of the activity test of active component A and active component B against plant pathogenic fungi are shown in Table 1.

[0027] Table 1 EC values ​​of active component A and active component B against plant pathogenic fungi 50

[0028]

[0029] Example 3: Indoor activity test of a mixture of leucoderma alkaloids and active component B against Rhizoctonia solani

[0030] The synergistic effect of fungicides is calculated according to the Wadley (1967) formula:

[0031]

[0032] Where a and b represent the proportion of cephalaenopsis alkaloids (A) and plant essential oils (B) in the mixture, respectively. 50 (A), E.C. 50 (B) represent the actual observed EC 50 Value, EC 50 (Exp) represents the theoretical EC after the mixture of A and B in the ratio of a:b 50 Value, EC 50 (Obs) is the actual observed EC after the mixture of A and B in the ratio of a:b 50 SR>1.5 indicates synergism; SR<0.5 indicates antagonism; SR between 0.5 and 1.5 indicates additive effect.

[0033] The synergistic effect of the mixture of fennel alkaloids and active component B on the indoor toxicity of Rhizoctonia solani is shown in Table 2.

[0034] Table 2 The synergistic effect of the mixture of fennel alkaloids and active component B on the indoor toxicity of Rhizoctonia solani

[0035]

[0036] As shown in Table 2, when the mass ratio of leucophylla and active component B was 1:1 and 1:20, it had a more obvious synergistic effect on Rhizoctonia solani, especially when the mass ratio of leucophylla and West Indian sandalwood oil was 1:20, the SR was 2.26.

[0037] Example 4: Indoor activity test of a mixture of fennel alkaloids and active component B against rapeseed sclerotinia

[0038] Table 3 shows the synergistic effect of the mixture of fennel alkaloids and active component B on the indoor toxicity of rapeseed sclerotinia sclerotinia.

[0039] Table 3 The synergistic effect of the mixture of fennel alkaloids and active component B on the indoor toxicity of rapeseed sclerotinia

[0040]

[0041] As shown in Table 3, the mixing mass ratio of leucophylla and active component B at 1:10 and 1:20 has a significant synergistic effect on Sclerotinia sclerotiorum of rapeseed. When the mass ratio is 1:20, the synergistic effect of leucophylla with lemongrass essential oil, zedoary oil and west Indian sandalwood oil is the most obvious, and the SR values ​​are 5.30, 4.93 and 6.06, respectively.

[0042] Example 5: Indoor activity test of a mixture of fennel alkaloids and active component B against tomato gray mold

[0043] The synergistic effect of the mixture of spatholobiline and active component B on the indoor toxicity of tomato gray mold is shown in Table 4.

[0044] Table 4 The synergistic effect of the mixture of fennel alkaloids and active component B on the indoor toxicity of tomato gray mold

[0045]

[0046] As shown in Table 3, when the mass ratio of cephalotaxine to active component B was 1:10 and 1:20, there was no synergistic effect on tomato gray mold, and all the combinations had antagonistic effects.

[0047] Example 6: Indoor activity test of a mixture of fennel alkaloids and active component B against wheat scab

[0048] The synergistic effect of the mixture of fennel alkaloids and active component B on the indoor toxicity of wheat fusarium rust is shown in Table 5.

[0049] Table 5 The synergistic effect of the mixture of fennel alkaloids and active component B on the indoor toxicity of wheat fusarium head blight

[0050]

[0051] As shown in Table 5, the mixing mass ratio of leucoderma alkaloids and active component B at 1:10 and 1:20 has a synergistic effect on wheat fusarium head blight, but it is not obvious. Only the synergistic effect of leucoderma alkaloids and lemongrass essential oil is more obvious, with an SR value of 2.55 at 1:10, and no synergistic effect at a ratio of 1:20.

[0052] Example 7: Indoor activity test of a mixture of fennel alkaloids and active component B against rice blast

[0053] The synergistic effect of the mixture of fennel alkaloids and active component B on the indoor toxicity of rice blast is shown in Table 6.

[0054] Table 6 The synergistic effect of the mixture of fennel alkaloids and active component B on the indoor toxicity of rice blast

[0055]

[0056] As shown in Table 6, the mixing mass ratio of leucophylla and active component B has a synergistic effect at 1:10, but it is not obvious. At the ratio of 1:20, only leucophylla and violet essential oil have a synergistic effect, and the SR value is 1.59.

[0057] In summary, cephaladine and plant essential oil have a synergistic effect on some strains at a ratio of 1:10. At a ratio of 1:20, the most obvious synergistic effect is achieved by the combination of cephaladine and West Indian sandalwood oil against rapeseed sclerotinia, with an SR value of up to 6.06. The bactericidal composition containing cephaladine and plant essential oil described in the present invention can significantly reduce the dosage of cephaladine, and compared with a single agent, expands the bactericidal spectrum. Based on this, the bactericidal composition described in the invention is worthy of further research and development.

Claims

1. A use of a bactericidal composition containing cephalosporin and plant essential oil in preventing and treating diseases caused by Rhizoctonia solani, characterized in that: The bactericidal composition comprises active component A and active component B; wherein active component A has the following molecular structure characteristics The active component B is a plant essential oil, and the plant essential oil is one of calamus oil, zedoary oil, and West Indian sandalwood oil; wherein the mass ratio of leucophylla to calamus oil is 1:10; or the mass ratio of leucophylla to zedoary oil is 1:10; or the mass ratio of leucophylla to West Indian sandalwood oil is 1:10 or 1:

20.

2. Use of a bactericidal composition containing cephalosporin and plant essential oil in preventing and treating diseases caused by Sclerotinia sclerotiorum of rapeseed, characterized in that: The bactericidal composition comprises active component A and active component B; wherein active component A has the following molecular structure characteristics The active component B is a plant essential oil, and the plant essential oil is one of patchouli essential oil, calamus oil, lemongrass essential oil, zedoary oil, and West Indian sandalwood oil; the mass ratio of leucoderma alkaloids to the plant essential oil is 1:10 or 1:

20.

3. Use of a bactericidal composition containing cephalosporin and plant essential oil in preventing and treating diseases caused by wheat fusarium sphaeroides, characterized in that: The bactericidal composition comprises active component A and active component B; wherein active component A has the following molecular structure characteristics The active component B is a plant essential oil, which is one of garlic essential oil, lemongrass essential oil and West Indian sandalwood oil; the mass ratio of leucoderma alkaloids to the plant essential oil is 1:

10.

4. Use of a bactericidal composition containing cephalosporin and plant essential oil in preventing and treating diseases caused by rice blast fungus, characterized in that: The bactericidal composition comprises active component A and active component B; wherein active component A has the following molecular structure characteristics The active component B is a plant essential oil, which is one of calamus oil, lemongrass essential oil and violet essential oil; wherein the mass ratio of leucophylla to calamus oil is 1:10; or the mass ratio of leucophylla to lemongrass essential oil is 1:10; or the mass ratio of leucophylla to violet essential oil is 1:10 or 1:20.

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