Attractant for noctuid black egg bees for preventing and controlling prodenia litura and obtaining method of attractant

Abstract

The invention discloses a noctuid black egg bee attractant for preventing and controlling prodenia litura, and the attractant comprises a solvent and at least one of the following components: 1, 3-dichlorobenzene, benzothiazole and octane. The attractant disclosed by the invention can be used for more effectively attracting the noctuid black egg bees to parasitize the prodenia litura eggs, so that the increase of the quantity of pests is inhibited, the pest population gradually disappears, and the aim of preventing and controlling the pests is fulfilled. The prodenia litura attractant not only belongs to a green, non-toxic and nuisanceless attractant, but also can solve a series of problems of pesticide residue, environmental pollution, food safety and the like caused by chemical prevention and control, and has important significance on green prevention and control of prodenia litura.

Description

Technical Field

[0001] The invention relates to the technical field of biological control, and in particular to an attractant for the black egg wasp of the Spodoptera litura used for controlling the Spodoptera litura and a method for obtaining the attractant. Background Art

[0002] Tobacco pests mainly include the armyworm, aphids, tobacco budworms, cutworms, etc., which have a serious impact on the yield and quality of tobacco. Traditional chemical pest control has a great impact on the quality of tobacco, and the cost of control is getting higher and higher, and it pollutes the environment. Biological control of tobacco pests is a scientific and effective method.

[0003] Spodoptera litura Fabricius belongs to the family Noctuidae of the order Lepidoptera and is one of the main pests on tobacco. For a long time, the control of Spodoptera litura mainly relied on chemical pesticides. However, with the long-term and large-scale use of chemical pesticides, Spodoptera litura gradually developed resistance to them, and the control effect decreased, which in turn caused problems such as pesticide residues, environmental pollution and food safety. Therefore, biological control factors are urgently needed to achieve pollution-free, sustainable and green control of Spodoptera litura, such as the use of fungi, bacteria, parasitic wasps, etc.

[0004] Telenomus remus Nixon, belonging to the family Platygastridae of the order Hymenoptera, is an important parasitic natural enemy of many moth pests in the egg stage, and can effectively prevent and control Spodoptera litura. The parasitic wasp can efficiently parasitize eggs of multi-layered Spodoptera pests, and even the parasitism rate of the innermost layer can reach more than 90%. It also has the advantages of strong fertility and easy colonization in the field. Therefore, Telenomus remus Nixon is considered to be an important natural enemy insect resource in the biological control of Spodoptera pests, and has great application value. In order to improve the parasitic effect of Telenomus remus Nixon on tobacco Spodoptera litura, an attractant for Telenomus remus Nixon with better attracting effect is urgently needed in the prior art. Summary of the invention

[0005] The technical problem solved by the invention is to provide an attractant for preventing and controlling the black egg wasps of the Spodoptera litura and a method for obtaining the attractant.

[0006] The specific technical solutions are as follows:

[0007] An attractant for controlling the black egg wasp of Spodoptera litura, the attractant comprising a solvent and at least one of the following components: 1,3-dichlorobenzene, benzothiazole, and octane.

[0008] Preferably, the attractant comprises a solvent and 1,3-dichlorobenzene, and the concentration of 1,3-dichlorobenzene is 1 μg / μL.

[0009] Preferably, the attractant comprises a solvent and benzothiazole, and the concentration of benzothiazole is 1 μg / μL.

[0010] Preferably, the attractant comprises a solvent and octane, and the concentration of octane is 1 μg / μL.

[0011] Preferably, the attractant includes a solvent, 1,3-dichlorobenzene, and benzothiazole, and the concentrations of 1,3-dichlorobenzene and benzothiazole are both 1 μg / μL.

[0012] Preferably, the attractant includes solvent, benzothiazole and octane, and the concentrations of benzothiazole and octane are both 1 μg / μL.

[0013] Preferably, the attractant includes solvent, 1,3-dichlorobenzene and octane, and the concentrations of 1,3-dichlorobenzene and octane are both 1 μg / μL.

[0014] Preferably, the solvent is n-hexane.

[0015] The present invention also provides a method for obtaining the above-mentioned attractant for the black egg wasp of the Spodoptera litura for controlling the Spodoptera litura, comprising:

[0016] Step 1, providing tobacco leaves and Spodoptera litura eggs, wherein the Spodoptera litura eggs are placed on the tobacco leaves, and extracting volatiles from the tobacco leaves and the Spodoptera litura eggs: using an atmospheric sampler dynamic headspace method to collect and extract volatiles from the tobacco leaves and the Spodoptera litura eggs;

[0017] Step 2: Identify the volatiles of tobacco leaves and Spodoptera litura eggs: Use gas chromatography-mass spectrometry to analyze and identify the components of the volatiles;

[0018] Step 3: Determination of behavioral response: Conduct a Y-type olfactometer test on the volatiles of tobacco leaves and Spodoptera litura eggs to determine the behavioral response of the adults of Spodoptera litura to the volatiles to obtain the attractants.

[0019] Preferably, in the step 1, leaves of healthy tobacco plants that are free of pests and diseases and growing well are selected as the tobacco leaves.

[0020] The attractant for controlling the black egg wasp of Spodoptera litura provided by the present invention and the method for obtaining the same have the following technical effects:

[0021] The attractant provided can improve the parasitic effect of the noctuid black egg wasp on tobacco cutworm. Moreover, especially for the concentration of the attractant, which affects the effect of the lure, the inventors found that the concentration and the lure effect are not in a linear relationship, and determined the optimal concentration to achieve the best lure effect. The attractant of the present invention can more effectively lure the noctuid black egg wasp to parasitize the cutworm eggs, thereby inhibiting the growth of the number of pests and gradually eliminating the pest population, thereby achieving the purpose of pest control. The present invention is not only a green, non-toxic, and pollution-free attractant, but also can solve a series of problems such as pesticide residues, environmental pollution, and food safety caused by chemical control, and is of great significance for the green control of cutworm.

[0022] Among them, n-hexane was used as the solvent. First, parasitic wasps have a certain tendency to n-hexane, so the experimental results using n-hexane as the control are more convincing; secondly, when collecting and cleaning the crude extracts of volatiles, in order to completely remove all compounds, n-hexane, which is easy to clean, was selected, because other solvents, such as paraffin oil, were not thorough enough.

[0023] Among them, in step 1, the leaves of healthy tobacco plants without pests and diseases and growing well are selected as the tobacco leaves, so as to determine the volatiles of the tobacco leaves and exclude other factors as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a comparative diagram of the attracting effects of 1,3-dichlorobenzene, benzothiazole, octane and the corresponding control group experiments on the adults of Spodoptera exigua;

[0025] Figure 2 This is a comparative diagram of the attracting effects of different concentrations of 1,3-dichlorobenzene and the corresponding control group experiments on the adults of Spodoptera exigua;

[0026] Figure 3 It is a comparative diagram of the attracting effect of different concentrations of benzothiazole and the corresponding control group on the adults of Spodoptera exigua;

[0027] Figure 4 It is a comparative diagram of the attracting effect of different octane concentrations and the corresponding control group experiments on the adults of Spodoptera exigua;

[0028] Figure 5 The control group experiments corresponding to the compositions of 1,3-dichlorobenzene + benzothiazole, 1,3-dichlorobenzene + octane, and benzothiazole + octane show the attracting effects on the adults of the noctuid black egg wasp. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings and implementation modes.

[0030] The invention provides an attractant for preventing and controlling the black egg wasps of Spodoptera litura. The attractant comprises a solvent and at least one of the following components: 1,3-dichlorobenzene, benzothiazole and octane.

[0031] For the component 1,3-dichlorobenzene, the following comparative experiment was conducted:

[0032] A Y-shaped tube is provided, a treatment group (a mixture of 1,3-dichlorobenzene and a solvent) is placed in one branch of the Y-shaped tube, a control group (solvent) is placed in another branch of the Y-shaped tube, and a number of Spodoptera exigua is placed in the main tube of the Y-shaped tube connected to the two branch tubes. After a period of time, the selection rate of the Spodoptera exigua for the treatment group and the control group can be obtained. The results are shown in FIG. Figure 1 .

[0033] For the component benzothiazole, the following comparative experiment was conducted:

[0034] A Y-shaped tube is provided, a branch tube of the Y-shaped tube is placed in a treatment group (a mixture of benzothiazole and a solvent), another branch tube of the Y-shaped tube is placed in a control group (solvent), and a number of Spodoptera exigua is placed in the main tube of the Y-shaped tube connected to the two branch tubes. After a period of time, the selection rate of the Spodoptera exigua for the treatment group and the control group can be obtained. The results are shown in FIG. Figure 1 .

[0035] For the component octane, the following comparative experiment was conducted:

[0036] A Y-shaped tube is provided, a treatment group (a mixture of octane and solvent) is placed in one branch of the Y-shaped tube, a control group (solvent) is placed in another branch of the Y-shaped tube, and a number of Spodoptera exigua is placed in the main tube of the Y-shaped tube connected to the two branch tubes. After a period of time, the selection rate of the Spodoptera exigua for the treatment group and the control group can be obtained. The results are shown in FIG. Figure 1 .

[0037] Can from Figure 1 It can be seen intuitively that any of 1,3-dichlorobenzene, benzothiazole and octane has a good attractant effect.

[0038] Furthermore, the attractant includes a solvent and 1,3-dichlorobenzene, and the concentration of 1,3-dichlorobenzene is 1 μg / μL.

[0039] For the ingredient 1,3-dichlorobenzene, four treatment groups with concentrations of 0.1 μg / μL, 1 μg / μL, 10 μg / μL and 100 μg / μL were provided, and the following four comparative experiments were performed respectively:

[0040] (1) A Y-shaped tube is provided. A treatment group (a mixture of 1,3-dichlorobenzene and a solvent, with a 1,3-dichlorobenzene concentration of 0.1 μg / μL) is placed in one branch of the Y-shaped tube, and a control group (solvent) is placed in another branch of the Y-shaped tube. A number of Spodoptera exigua is placed in the main tube of the Y-shaped tube connected to the two branch tubes. After a period of time, the selection rate of the Spodoptera exigua for the treatment group and the control group can be obtained. The results are shown in FIG. Figure 2 .

[0041] (2) A Y-shaped tube is provided. A treatment group (a mixture of 1,3-dichlorobenzene and a solvent, with a 1,3-dichlorobenzene concentration of 1 μg / μL) is placed in one branch of the Y-shaped tube, and a control group (solvent) is placed in another branch of the Y-shaped tube. A number of Spodoptera exigua is placed in the main tube of the Y-shaped tube connected to the two branch tubes. After a period of time, the selection rate of the Spodoptera exigua for the treatment group and the control group can be obtained. The results are shown in FIG. Figure 2 .

[0042] (3) A Y-shaped tube is provided. A treatment group (a mixture of 1,3-dichlorobenzene and a solvent, with a 1,3-dichlorobenzene concentration of 10 μg / μL) is placed in one branch of the Y-shaped tube, and a control group (solvent) is placed in another branch of the Y-shaped tube. A number of Spodoptera exigua is placed in the main tube of the Y-shaped tube connected to the two branch tubes. After a period of time, the selection rate of the Spodoptera exigua for the treatment group and the control group can be obtained. The results are shown in FIG. Figure 2 .

[0043] (4) A Y-shaped tube is provided. A treatment group (a mixture of 1,3-dichlorobenzene and a solvent, with a 1,3-dichlorobenzene concentration of 100 μg / μL) is placed in one branch of the Y-shaped tube, and a control group (solvent) is placed in another branch of the Y-shaped tube. A number of Spodoptera exigua is placed in the main tube of the Y-shaped tube connected to the two branch tubes. After a period of time, the selection rate of Spodoptera exigua for the treatment group and the control group can be obtained. The results are shown in FIG. Figure 2 .

[0044] It can be seen that the attractant effect is best when the concentration of 1,3-dichlorobenzene is 1μg / μL.

[0045] Similarly, for the component benzothiazole, four treatment groups with concentrations of 0.1 μg / μL, 1 μg / μL, 10 μg / μL and 100 μg / μL were provided, and four groups of comparative experiments were performed respectively. The specific process was the same as above, and the results are shown in Figure 3 .

[0046] The attractant includes a solvent and benzothiazole, and the attractant effect is best when the concentration of benzothiazole is 1 μg / μL.

[0047] Similarly, for the component octane, four treatment groups with concentrations of 0.1 μg / μL, 1 μg / μL, 10 μg / μL and 100 μg / μL were provided, and four groups of comparative experiments were conducted respectively. The specific process was the same as above, and the results are shown in Figure 4 .

[0048] The attractant includes solvent and octane, and the attractant effect is best when the concentration of octane is 1 μg / μL.

[0049] Furthermore, the attractant includes a solvent, 1,3-dichlorobenzene, and benzothiazole, and the concentrations of 1,3-dichlorobenzene and benzothiazole are both 1 μg / μL. Or

[0050] The attractant includes solvent, benzothiazole, and octane, and the concentration of benzothiazole and octane is 1 μg / μL.

[0051] The attractants include solvent, 1,3-dichlorobenzene and octane, and the concentrations of 1,3-dichlorobenzene and octane are both 1 μg / μL.

[0052] like Figure 5 As shown, the combination method and the concentration limit are carried out in the comparative experiment using the Y tube mentioned above. Considering the cost and other conditions, it can be seen that the combination method and the concentration limit can make the attracting effect better. For example, for "the attractant includes solvent, 1,3-dichlorobenzene, and benzothiazole", the experimental process is as follows:

[0053] A Y-shaped tube is provided, a treatment group (solvent, 1,3-dichlorobenzene, benzothiazole, and the concentrations of 1,3-dichlorobenzene and benzothiazole are 1μg / μL) is placed in one branch of the Y-shaped tube, a control group (solvent) is placed in another branch of the Y-shaped tube, and a number of Spodoptera exigua is placed in the main tube of the Y-shaped tube connected to the two branch tubes. After a period of time, the selection rate of Spodoptera exigua for the treatment group and the control group can be obtained. The results are shown in FIG. Figure 5 .

[0054] Similarly, the above experiments were conducted for "attractants including solvent, benzothiazole, octane" and "attractants including solvent, 1,3-dichlorobenzene, octane", and the results are shown in Figure 5 .

[0055] Furthermore, the solvent is n-hexane. n-hexane is used as the solvent. Firstly, parasitic wasps have a certain tendency to n-hexane, so the experimental results using n-hexane as the control are more convincing; secondly, when collecting and cleaning the crude volatile extract, in order to completely remove all compounds, n-hexane, which is easy to clean, is selected, because other solvents, such as paraffin oil, are not thorough enough.

[0056] The present invention also provides a method for obtaining the above-mentioned attractant for the black egg wasp of the Spodoptera litura for controlling the Spodoptera litura, comprising:

[0057] Step 1, providing tobacco leaves and Spodoptera litura eggs, wherein the Spodoptera litura eggs are placed on the tobacco leaves, and extracting volatiles from the tobacco leaves and the Spodoptera litura eggs: using an atmospheric sampler dynamic headspace method to collect and extract volatiles from the tobacco leaves and the Spodoptera litura eggs;

[0058] Step 2: Identify the volatiles of tobacco leaves and Spodoptera litura eggs: Use gas chromatography-mass spectrometry to analyze and identify the components of the volatiles;

[0059] Step 3: Determination of behavioral response: Conduct a Y-type olfactometer test on the volatiles of tobacco leaves and Spodoptera litura eggs to determine the behavioral response of the adults of Spodoptera litura to the volatiles to obtain the attractants.

[0060] Among them, in the step 1, the leaves of healthy tobacco plants without pests and diseases and growing well are selected as the tobacco leaves. This is to exclude other factors as much as possible when determining the volatiles of tobacco leaves.

[0061] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An attractant for the black egg wasp of the Spodoptera litura used to control the Spodoptera litura, characterized in that: The attractant comprises a solvent and at least one of the following components: 1,3-dichlorobenzene, benzothiazole, and octane.

2. The attractant for the black egg wasp of the Spodoptera litura for controlling the Spodoptera litura according to claim 1, characterized in that: The attractant includes a solvent and 1,3-dichlorobenzene, and the concentration of 1,3-dichlorobenzene is 1 μg / μL.

3. The attractant for the black egg wasp of the Spodoptera litura for controlling the Spodoptera litura according to claim 1, characterized in that: The attractant includes a solvent and benzothiazole, and the concentration of benzothiazole is 1 μg / μL.

4. The attractant for the black egg wasp of the Spodoptera litura for controlling the Spodoptera litura according to claim 1, characterized in that: The attractant includes a solvent and octane, and the concentration of octane is 1 μg / μL.

5. The attractant for the black egg wasp of Spodoptera litura for controlling Spodoptera litura according to claim 1, characterized in that: The attractant includes solvent, 1,3-dichlorobenzene and benzothiazole, and the concentrations of 1,3-dichlorobenzene and benzothiazole are both 1 μg / μL.

6. The attractant for the black egg wasp of the Spodoptera litura for controlling the Spodoptera litura according to claim 1, characterized in that: The attractant includes solvent, benzothiazole and octane, and the concentrations of benzothiazole and octane are both 1 μg / μL.

7. The attractant for the black egg wasp of the Spodoptera litura for controlling the Spodoptera litura according to claim 1, characterized in that: The attractants include solvent, 1,3-dichlorobenzene and octane, and the concentrations of 1,3-dichlorobenzene and octane are both 1 μg / μL.

8. The attractant for controlling the black egg wasp of Spodoptera litura according to any one of claims 1 to 7, characterized in that: The solvent is n-hexane.

9. A method for obtaining the attractant for the black egg wasp of Spodoptera litura for controlling Spodoptera litura according to claims 1 to 8, characterized in that: include: Step 1, providing tobacco leaves and Spodoptera litura eggs, wherein the Spodoptera litura eggs are placed on the tobacco leaves, and extracting volatiles from the tobacco leaves and the Spodoptera litura eggs: using an atmospheric sampler dynamic headspace method to collect and extract volatiles from the tobacco leaves and the Spodoptera litura eggs; Step 2: Identify the volatiles of tobacco leaves and Spodoptera litura eggs: Use gas chromatography-mass spectrometry to analyze and identify the components of the volatiles; Step 3: Determination of behavioral response: Conduct a Y-type olfactometer test on the volatiles of tobacco leaves and Spodoptera litura eggs to determine the behavioral response of the adults of Spodoptera litura to the volatiles to obtain the attractants.

10. The method for obtaining the attractant for the black egg wasp of the Spodoptera litura for controlling the Spodoptera litura according to claim 9, characterized in that: In the step 1, leaves of healthy tobacco plants that are free of pests and diseases and growing well are selected as the tobacco leaves.

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