An insect pathogenic preparation for preventing and treating diaprepes abbreviatus, a preparation method and application thereof

Abstract

The application discloses an insect pathogenic preparation for preventing and treating Cylas formicarius, a preparation method and application thereof, and belongs to the field of agricultural technology. The insect pathogenic preparation for preventing and treating Cylas formicarius comprises a corpse compound agent of an insect pathogenic nematode and a sweet potato root protection agent. The corpse compound agent of the insect pathogenic nematode comprises an insect pathogenic nematode corpse agent, an artificial feed of Cylas formicarius, a polyphenol oxidase inhibitor and trehalose (alpha,alpha) dry powder, and the mass ratio is 1-3:6-8:0.25-0.35:0.6-0.8. Each 1L of the sweet potato root protection agent contains 0.03-0.05g of a biocontrol bacterium agent, 3-5g of a Cylas formicarius repellent and 90-110ml of a bonding agent, and the volume is supplemented with water. The application further discloses a preparation method of the insect pathogenic preparation and application thereof in preventing and treating Cylas formicarius. The insect pathogenic preparation can prevent and treat Cylas formicarius through multiple actions, and has a good prevention and treatment effect on adult and larva of Cylas formicarius.

Description

Technical Field

[0001] This invention belongs to the field of agricultural technology, specifically relating to an insect pathogen preparation for controlling the sweet potato weevil, its preparation method, and its application. Background Technology

[0002] The sweet potato weevil (Cylas formicarius) is a common pest of sweet potatoes. Both adults and larvae can damage sweet potatoes, but the larvae cause particularly severe damage. The larvae primarily bore into the tubers and vines, creating irregular, crisscrossing tunnels where they defecate. The sweet potato weevil larvae live entirely within the tubers or vine tops. After hatching, the larvae bore into the tubers and vine tops, creating winding tunnels, leaving behind piles of white or brown frass. When feeding within the vines, the larvae generally bore downwards into relatively straight tunnels, causing the damaged area to gradually swell. Some larvae may also bore into the tuber through the stem. Each tunnel typically contains only one larva, and each tuber may contain as few as one or two larvae, but can contain over 100 larvae in some cases.

[0003] Affected sweet potato tubers will develop a honeycomb-like appearance, turning black or dark brown, and are susceptible to diseases such as sweet potato black rot and sweet potato soft rot, leading to decay. These affected tubers will produce a distinctive pungent, fishy smell, earning them the name "stinky potatoes," and are completely inedible. Even when used as animal feed, they can cause poisoning and death in livestock. In affected areas, the sweet potato weevil causes annual losses of approximately 15% to 20%, and in severe cases, losses can reach 50%, even leading to total crop failure.

[0004] Currently, the main control methods for sweet potato weevils are as follows: (1) Chemical control: Spraying or drenching the roots with chemical pesticides such as phoxim and trichlorfon. This method is fast-acting, but long-term use can lead to soil pollution, increase the pest's resistance to pesticides, and pose certain risks to the environment and human health. (2) Physical control: This includes covering the ground with plastic film and setting up traps. Plastic film can reduce the chance of adult insects laying eggs, and traps can capture adult insects. These methods are relatively environmentally friendly, but they are complicated to operate, have limited effects, and are difficult to promote and apply on a large scale. (3) Biological control: Using natural enemies such as parasitic wasps and predatory insects to control pests. In addition, biological pesticides such as Bacillus thuringiensis (Bt) can also be used. Biological control methods are environmentally friendly, but the effects are slow and are greatly affected by climate and ecological conditions. (4) Agricultural control: Reducing the overwintering sites of pests through crop rotation, deep plowing of the soil, and removal of weeds in the field. This method is simple and easy to implement, but it requires long-term adherence and has limited effects on pests that have already occurred. (5) Genetic engineering: Breeding insect-resistant sweet potato varieties through transgenic technology. This method has great potential, but it is still in the research stage and has not yet been widely used, and there are ethical and safety controversies.

[0005] Each of these control methods has its advantages and disadvantages. Chemical control is fast-acting, but it poses potential risks to the environment and human health. Physical and biological control methods are more environmentally friendly, but they are complex to operate and have limited effectiveness. Agricultural control requires long-term commitment and has limited effectiveness against existing pests. Genetic engineering methods have great potential, but are still in the research stage. Therefore, only by comprehensively using multiple methods and considering the actual situation can the damage caused by the sweet potato weevil be controlled more effectively. Summary of the Invention

[0006] One of the objectives of this invention is to provide an insect pathogenic agent for controlling the sweet potato weevil, which can act in multiple ways to control the sweet potato weevil pest and has a good control effect on both adult and larval sweet potato weevils.

[0007] The second objective of this invention is to provide a method for preparing the insect pathogen agent.

[0008] A third objective of this invention is to provide the application of this insect pathogen preparation.

[0009] The fourth objective of this invention is to provide a method for using the insect pathogen preparation.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0011] In a first aspect, the present invention discloses an insect pathogen preparation for controlling the sweet potato weevil, comprising a compound of insect corpses of insect pathogenic nematodes and a sweet potato root protectant;

[0012] The compound preparation of insect carcasses of entomopathogenic nematodes includes entomopathogenic nematode carcass agent, artificial feed for sweet potato weevils, polyphenol oxidase inhibitor and trehalose (α,α) dry powder, with a mass ratio of 1-3:6-8:0.25-0.35:0.6-0.8; preferably 2:7:0.3:0.7;

[0013] Each 1L of sweet potato root protectant contains 0.03-0.05g of biocontrol agent, 3-5g of sweet potato weevil repellent, 90-110ml of binder, and water to make up the volume; preferably, it contains 0.04g of biocontrol agent, 4g of sweet potato weevil repellent, 100ml of binder, and water to make up the volume.

[0014] In some embodiments of the present invention, the preparation method of the entomopathogenic nematode cadaver agent includes the following steps: taking 4-5 instar mature mealworm larvae and placing them in a container, adding the infective entomopathogenic nematodes; the intact corpse of the mealworm larvae obtained after death is the entomopathogenic nematode cadaver agent;

[0015] Preferably, one mature mealworm larva is treated with 100 to 400 infective entomopathogenic nematodes.

[0016] In some embodiments of the present invention, the artificial feed for sweet potato weevils is made from the following components in parts by weight: 8-12 parts sweet potato tubers, 5-8 parts sweet potato flour, 1-2 parts casein, 1-2 parts cellulose, 3-5 parts glucose, 3.00-5.26 parts yeast powder, 7.50-9.78 parts soybean flour, 4.49-5.64 parts sucrose, 0.30-0.32 parts ascorbic acid, 0.060-0.065 parts cholesterol, 0.02-0.05 parts methylparaben, 0.04-0.1 parts potassium sorbate, 0.007-0.008 parts compound vitamin B, 1.50-2.56 parts agar, and 70-75 parts water;

[0017] Preferably, the mixture comprises 10 parts sweet potato tubers, 6.5 parts sweet potato flour, 1.5 parts casein, 1.5 parts cellulose, 4 parts glucose, 4.13 parts yeast powder, 8.6 parts soybean flour, 5.06 parts sucrose, 0.31 parts ascorbic acid, 0.062 parts cholesterol, 0.035 parts methylparaben, 0.07 parts potassium sorbate, 0.007 parts compound vitamin B, 2.03 parts agar, and 72.5 parts water.

[0018] In some embodiments of the present invention, the polyphenol oxidase inhibitor includes gallic acid.

[0019] In some embodiments of the present invention, the sweet potato weevil repellent includes at least one of Sichuan pepper, catnip, and marigold;

[0020] The adhesive includes glutinous rice glue;

[0021] The biocontrol agent includes Beauveria bassiana agent.

[0022] Secondly, this invention discloses a method for preparing an insect pathogen agent to control the sweet potato weevil. This method involves preparing a compound agent containing the cadavers of the insect pathogenic nematode and a sweet potato root protectant. The preparation method of the compound agent containing the cadavers of the insect pathogenic nematode includes the following steps:

[0023] S1. Preparation of artificial feed for sweet potato weevils: sweet potato tuberous roots are processed into a paste, then mixed evenly with the remaining components to obtain a paste-like mixture, which is then sterilized to obtain artificial feed for sweet potato weevils.

[0024] S2. Mix the polyphenol oxidase inhibitor with the artificial feed for sweet potato weevils to form a paste;

[0025] S3. Wrap the insect corpse agent of entomopathogenic nematodes with the mud paste prepared in step S2; and then wrap it with a layer of dry powder containing trehalose (α,α) to obtain the insect corpse compound of entomopathogenic nematodes;

[0026] The preparation method of sweet potato root protectant includes the following steps: crush sweet potato weevil repellent into powder, mix it evenly with glutinous rice glue and Beauveria bassiana agent, add water to form a hydrogel, and thus obtain sweet potato root protectant.

[0027] In this invention, the insect pathogenic nematode cadaver agent is wrapped in mud paste and then coated with a layer of dry powder containing trehalose (α,α). This seals the insect pathogenic nematode cadaver agent in the feed, protecting the integrity of the cadaver agent while preserving the nematode's vitality.

[0028] Thirdly, this invention discloses the application of the above-mentioned insect pathogen preparation in the control of sweet potato weevils.

[0029] Fourthly, this invention discloses a method for controlling sweet potato weevils using the aforementioned insect pathogen preparation.

[0030] In some embodiments of the present invention, when sweet potatoes are planted, a compound agent containing the cadavers of entomopathogenic nematodes is placed at the base of the sweet potato seedlings, and a root protectant is evenly dripped onto the sweet potato roots.

[0031] In some embodiments of the present invention, the dosage of sweet potato root protectant is 20-25 ml per seedling;

[0032] Preferably, the dripping area is a range of 10-15 cm in diameter centered on the base of the sweet potato seedling.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] This invention is scientifically designed and ingeniously conceived. Its insect pathogen formulation exerts a multi-pronged effect in controlling the sweet potato weevil. By coating the artificial feed for the sweet potato weevil onto the surface of the insect nematode cadaver, some sweet potato weevil larvae are attracted to feed, thus reducing their damage to the sweet potato. Simultaneously, this also helps guide the sweet potato weevil larvae to the vicinity of the insect nematode, shortening the time the nematode takes to find a host. Furthermore, the addition of a polyphenol oxidase inhibitor, such as gallic acid, effectively inhibits the humoral immune function of the sweet potato weevil, making it easier and faster for the insect nematode to infect and kill the weevil. The synergistic effect of these three actions greatly enhances the control efficacy of the nematode against the sweet potato weevil, effectively protecting the sweet potato.

[0035] The sweet potato root protectant of this invention is applied by uniform dripping onto the roots of sweet potatoes, with the dripping area forming a circle centered on the base of the sweet potato seedling, thereby forming a protective layer around the root system. This not only repels the sweet potato weevil from burrowing into the soil and reduces its damage to sweet potato tubers by drilling and laying eggs, but also works effectively when adult weevils come into contact with the root protective layer. Due to the sticky texture of the glutinous rice glue in the protective layer, it can initially adhere to and trap approaching adult sweet potato weevils, preventing their invasion of the root system. Furthermore, when the sweet potato weevil passes through the protective layer, it picks up deadly bacteria, which infect and ultimately kill the hatched larvae. Detailed Implementation

[0036] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for illustrative purposes only and not for limiting the scope of the invention. Unless otherwise specified, specific conditions in the embodiments are performed under conventional conditions or conditions recommended by the manufacturer. Reagents or instruments used, unless otherwise specified, are all commercially available products.

[0037] The glutinous rice glue described in this embodiment of the invention is food-grade glutinous rice glue.

[0038] The entomopathogenic nematode described in this invention is a commercially available strain that is resistant to high temperatures. The entomopathogenic nematode used in the embodiments of this invention is *Steinernema carpocapsae*.

[0039] The compound vitamin B mentioned in this invention is a compound vitamin B tablet produced by Huazhong Pharmaceutical Co., Ltd.

[0040] The Beauveria bassiana described in this invention is produced by Shanxi Lvhai Pesticide Technology Co., Ltd., and its content is 40 billion cells / gram.

[0041] The 1% bifenthrin·thiamethoxam granules (Yingzhuang) described in this invention are produced by Jiangmen Plant Protection Co., Ltd., and have a total active ingredient content of 1%, a bifenthrin content of 0.5%, and a thiamethoxam content of 0.5%.

[0042] Example 1

[0043] This embodiment discloses a method for preparing an insect pathogen agent for controlling sweet potato weevils according to the present invention. The insect pathogen agent is composed of a compound agent of insect nematode carcasses and a sweet potato root protectant.

[0044] The compound preparation of insect corpses of entomopathogenic nematodes includes entomopathogenic nematode cadavers, artificial feed for sweet potato weevils, gallic acid and trehalose (α,α) dry powder, with a mass ratio of 2:7:0.3:0.7.

[0045] Each 1L of sweet potato root protectant contains 0.04g of Beauveria bassiana agent, 4g of Sichuan pepper (80-100 mesh), 100ml of glutinous rice glue, and water to make up the volume.

[0046] The preparation method of the compound preparation of worm carcasses of entomopathogenic nematodes includes the following steps:

[0047] (1) Preparation of insect pathogenic nematode cadaver: Take 4-5 instar mature mealworm larvae and place them in a container, add the infecting insect pathogenic nematodes to it; the intact corpse of the mealworm larvae obtained after death is the insect pathogenic nematode cadaver; 300 infecting insect pathogenic nematodes are used for one mature mealworm larva.

[0048] (2) Preparation of artificial feed for sweet potato weevils: Prepare the raw materials according to the following weight parts: 10 parts sweet potato tubers, 6.5 parts sweet potato flour, 1.5 parts casein, 1.5 parts cellulose, 4 parts glucose, 4.13 parts yeast powder, 8.6 parts soybean flour, 5.06 parts sucrose, 0.31 parts ascorbic acid, 0.062 parts cholesterol, 0.035 parts methylparaben, 0.07 parts potassium sorbate, 0.007 parts compound vitamin B, 2.03 parts agar, and 72.5 parts water. Process the sweet potato tubers into a paste, then mix them evenly with the remaining components to obtain a paste-like mixture. Sterilize the paste to obtain the artificial feed for sweet potato weevils.

[0049] (3) Mix gallic acid with artificial feed for sweet potato weevils evenly to form a paste;

[0050] (4) Wrap the insect corpse agent of entomopathogenic nematodes with the mud paste prepared in step (3); then wrap it with a layer of dry trehalose (α,α) powder to obtain the insect corpse compound agent of entomopathogenic nematodes.

[0051] The preparation method of sweet potato root protectant includes the following steps: take pepper powder that has been crushed to 80-100 mesh, mix it evenly with glutinous rice glue and Beauveria bassiana agent, add water to 1L to form a hydrogel, and the sweet potato root protectant is obtained.

[0052] In this embodiment, the insect corpse compound of the entomopathogenic nematode is applied at a rate of 1-2g per hole (containing 1-2 insect corpses), and the sweet potato root protectant is dripped at a rate of 20-25ml per seedling.

[0053] Example 2

[0054] This embodiment discloses a method for preparing an insect pathogen agent for controlling sweet potato weevils according to the present invention. The insect pathogen agent is composed of a compound agent of insect nematode carcasses and a sweet potato root protectant.

[0055] The compound preparation of insect corpses of entomopathogenic nematodes includes entomopathogenic nematode cadavers, artificial feed for sweet potato weevils, gallic acid and trehalose (α,α) dry powder, with a mass ratio of 3:6:0.25:0.75;

[0056] Each 1L of sweet potato root protectant contains 0.03g of Beauveria bassiana agent, 3g of catnip (80-100 mesh), and 90ml of glutinous rice glue. Add water to make up to 1L.

[0057] The preparation method of the compound preparation of worm carcasses of entomopathogenic nematodes includes the following steps:

[0058] (1) Preparation of insect pathogenic nematode cadaver: Take 4-5 instar mature mealworm larvae and place them in a container, add the infecting insect pathogenic nematodes to it; the intact corpse of the mealworm larvae obtained after death is the insect pathogenic nematode cadaver; 200 infecting insect pathogenic nematodes are used for one mature mealworm larva.

[0059] (2) Preparation of artificial feed for sweet potato weevils: Prepare the raw materials according to the following weight parts: 8 parts sweet potato tubers, 8 parts sweet potato flour, 2 parts casein, 1 part cellulose, 4.5 parts glucose, 5.26 parts yeast powder, 7.5 parts soybean flour, 4.49 parts sucrose, 0.3 parts ascorbic acid, 0.062 parts cholesterol, 0.05 parts methylparaben, 0.04 parts potassium sorbate, 0.007 parts compound vitamin B, 2.56 parts agar, and 72 parts water. Process the sweet potato tubers into a paste, then mix them evenly with the remaining components to obtain a paste-like mixture. Sterilize the paste to obtain the artificial feed for sweet potato weevils.

[0060] (3) Mix gallic acid with artificial feed for sweet potato weevils evenly to form a paste;

[0061] (4) Wrap the insect corpse agent of entomopathogenic nematodes with the mud paste prepared in step (3); then wrap it with a layer of dry trehalose (α,α) powder to obtain the insect corpse compound agent of entomopathogenic nematodes.

[0062] The preparation method of sweet potato root protectant includes the following steps: take catnip powder that has been crushed to 80-100 mesh, mix it evenly with glutinous rice glue and Beauveria bassiana agent, add water to 1L to form a hydrogel, and the sweet potato root protectant is obtained.

[0063] In this embodiment, the insect corpse compound of the entomopathogenic nematode is applied at a rate of 1-2g per hole (containing 1-2 insect corpses), and the sweet potato root protectant is dripped at a rate of 20-25ml per seedling.

[0064] Example 3

[0065] This embodiment discloses a method for preparing an insect pathogen agent for controlling sweet potato weevils according to the present invention. The insect pathogen agent is composed of a compound agent of insect nematode carcasses and a sweet potato root protectant.

[0066] The compound preparation of insect corpses of entomopathogenic nematodes includes entomopathogenic nematode cadavers, artificial feed for sweet potato weevils, gallic acid and trehalose (α,α) dry powder, with a mass ratio of 1:8:0.35:0.65;

[0067] Each 1L of sweet potato root protectant contains 0.05g of Beauveria bassiana agent, 3.5g of marigold (80-100 mesh), and 105ml of glutinous rice glue. Add water to make up to 1L.

[0068] The preparation method of the compound preparation of worm carcasses of entomopathogenic nematodes includes the following steps:

[0069] (1) Preparation of insect pathogenic nematode cadaver: Take 4-5 instar mature mealworm larvae and place them in a container, add the infecting insect pathogenic nematodes to it; the intact corpse of the mealworm larvae obtained after death is the insect pathogenic nematode cadaver; 400 infecting insect pathogenic nematodes are used for one mature mealworm larva.

[0070] (2) Preparation of artificial feed for sweet potato weevils: Prepare the raw materials according to the following weight parts: 12 parts sweet potato tubers, 5 parts sweet potato flour, 1 part casein, 2 parts cellulose, 3 parts glucose, 3 parts yeast powder, 8 parts soybean flour, 5.64 parts sucrose, 0.31 parts ascorbic acid, 0.065 parts cholesterol, 0.03 parts methylparaben, 0.1 parts potassium sorbate, 0.008 parts compound vitamin B, 1.5 parts agar, and 75 parts water. Process the sweet potato tubers into a paste, then mix them evenly with the remaining components to obtain a paste-like mixture. Sterilize the paste to obtain the artificial feed for sweet potato weevils.

[0071] (3) Mix gallic acid with artificial feed for sweet potato weevils evenly to form a paste;

[0072] (4) Wrap the insect corpse agent of entomopathogenic nematodes with the mud paste prepared in step (3); then wrap it with a layer of dry trehalose (α,α) powder to obtain the insect corpse compound agent of entomopathogenic nematodes.

[0073] The preparation method of sweet potato root protectant includes the following steps: take marigold powder crushed to 80-100 mesh, mix it evenly with glutinous rice glue and Beauveria bassiana agent, add water to 1L to form a hydrogel, and the sweet potato root protectant is obtained.

[0074] In this embodiment, the insect corpse compound of the entomopathogenic nematode is applied at a rate of 1-2g per hole (containing 1-2 insect corpses), and the sweet potato root protectant is dripped at a rate of 20-25ml per seedling.

[0075] Example 4

[0076] This embodiment discloses a method for preparing an insect pathogen agent for controlling sweet potato weevils according to the present invention. The insect pathogen agent is composed of a compound agent of insect nematode carcasses and a sweet potato root protectant.

[0077] The compound preparation of insect corpses of entomopathogenic nematodes includes entomopathogenic nematode cadavers, artificial feed for sweet potato weevils, gallic acid and trehalose (α,α) dry powder, with a mass ratio of 2.6:6.5:0.3:0.6;

[0078] Each 1L of sweet potato root protectant contains 0.04g of Beauveria bassiana agent, 2.3g of Sichuan pepper (80-100 mesh), 2.2g of catnip (80-100 mesh), and 110ml of glutinous rice glue. Add water to make up to 1L.

[0079] The preparation method of the compound preparation of worm carcasses of entomopathogenic nematodes includes the following steps:

[0080] (1) Preparation of insect pathogenic nematode cadaver: Take 4-5 instar mature mealworm larvae and place them in a container, add the infecting insect pathogenic nematodes to it; the intact corpse of the mealworm larvae obtained after death is the insect pathogenic nematode cadaver; 100 infecting insect pathogenic nematodes are used for one mature mealworm larva.

[0081] (2) Preparation of artificial feed for sweet potato weevils: Prepare the raw materials according to the following weight parts: 9 parts sweet potato tubers, 7 parts sweet potato flour, 2 parts casein, 1 part cellulose, 5 parts glucose, 4 parts yeast powder, 9.78 parts soybean flour, 5.2 parts sucrose, 0.32 parts ascorbic acid, 0.06 parts cholesterol, 0.04 parts methylparaben, 0.08 parts potassium sorbate, 0.008 parts compound vitamin B, 2 parts agar, and 70 parts water. Process the sweet potato tubers into a paste, then mix them evenly with the remaining components to obtain a paste-like mixture. Sterilize the paste to obtain the artificial feed for sweet potato weevils.

[0082] (3) Mix gallic acid with artificial feed for sweet potato weevils evenly to form a paste;

[0083] (4) Wrap the insect corpse agent of entomopathogenic nematodes with the mud paste prepared in step (3); then wrap it with a layer of dry trehalose (α,α) powder to obtain the insect corpse compound agent of entomopathogenic nematodes.

[0084] The preparation method of sweet potato root protectant includes the following steps: take pepper powder and catnip powder crushed to 80-100 mesh, mix them evenly with glutinous rice glue and Beauveria bassiana agent, add water to 1L to form a hydrogel, and the sweet potato root protectant is obtained.

[0085] In this embodiment, the insect corpse compound of the entomopathogenic nematode is applied at a rate of 1-2g per hole (containing 1-2 insect corpses), and the sweet potato root protectant is dripped at a rate of 20-25ml per seedling.

[0086] Example 5

[0087] This embodiment discloses a method for preparing an insect pathogen agent for controlling sweet potato weevils according to the present invention. The insect pathogen agent is composed of a compound agent of insect nematode carcasses and a sweet potato root protectant.

[0088] The compound preparation of insect corpses of entomopathogenic nematodes includes entomopathogenic nematode cadavers, artificial feed for sweet potato weevils, gallic acid and trehalose (α,α) dry powder, with a mass ratio of 2.1:6.8:0.3:0.8;

[0089] Each 1L of sweet potato root protectant contains 0.05g of Beauveria bassiana, 1.7g of Sichuan pepper (80-100 mesh), 1.7g of catnip (80-100 mesh), 1.6g of marigold (80-100 mesh), and 95ml of glutinous rice glue. Add water to make up to 1L.

[0090] The preparation method of the compound preparation of worm carcasses of entomopathogenic nematodes includes the following steps:

[0091] (1) Preparation of insect pathogenic nematode cadaver: Take 4-5 instar mature mealworm larvae and place them in a container, add the infecting insect pathogenic nematodes to it; the intact corpse of the mealworm larvae obtained after death is the insect pathogenic nematode cadaver; 200 infecting insect pathogenic nematodes are used for one mature mealworm larva.

[0092] (2) Preparation of artificial feed for sweet potato weevils: Prepare the raw materials according to the following weight parts: 11 parts sweet potato tubers, 6 parts sweet potato flour, 2 parts casein, 1.5 parts cellulose, 4 parts glucose, 4.5 parts yeast powder, 8.5 parts soybean flour, 5 parts sucrose, 0.3 parts ascorbic acid, 0.063 parts cholesterol, 0.02 parts methylparaben, 0.06 parts potassium sorbate, 0.007 parts compound vitamin B, 2.3 parts agar, and 71 parts water. Process the sweet potato tubers into a paste, then mix them evenly with the remaining components to obtain a paste-like mixture. Sterilize the paste to obtain the artificial feed for sweet potato weevils.

[0093] (3) Mix gallic acid with artificial feed for sweet potato weevils evenly to form a paste;

[0094] (4) Wrap the insect corpse agent of entomopathogenic nematodes with the mud paste prepared in step (3); then wrap it with a layer of dry trehalose (α,α) powder to obtain the insect corpse compound agent of entomopathogenic nematodes.

[0095] The preparation method of sweet potato root protectant includes the following steps: take pepper powder, catnip powder, marigold powder pulverized into 80-100 mesh, mix them evenly with glutinous rice glue and Beauveria bassiana agent, add water to 1L to form a hydrogel, and the sweet potato root protectant is obtained.

[0096] In this embodiment, the insect corpse compound of the entomopathogenic nematode is applied at a rate of 1-2g per hole (containing 1-2 insect corpses), and the sweet potato root protectant is dripped at a rate of 20-25ml per seedling.

[0097] Comparative Example 1

[0098] Compared to Comparative Example 1, Comparative Example 1 does not contain artificial feed for the sweet potato weevil. When preparing the compound preparation of entomopathogenic nematode carcasses, simply mix the entomopathogenic nematode carcass agent, trehalose, and gallic acid with a small amount of water. Add 50 ml of water to every 1000 g of entomopathogenic nematode carcass agent.

[0099] Comparative Example 2

[0100] Comparative Example 2, compared to Example 1, does not contain the polyphenol oxidase inhibitor gallic acid. In its preparation method, the cadaver of the entomopathogenic nematode is directly encapsulated in artificial feed for the sweet potato weevil. All other conditions are the same as in Example 1.

[0101] Comparative Example 3

[0102] Comparative Example 3, compared to Example 1, does not contain a sweet potato weevil repellent. No sweet potato weevil repellent was added during the preparation of the sweet potato root protectant, and all other conditions were the same as in Example 1.

[0103] Comparative Example 4

[0104] Comparative Example 4, compared to Example 1, does not contain biocontrol agents. No Beauveria bassiana was added during the preparation of the sweet potato root protectant; all other conditions were the same as in Example 1.

[0105] Comparative Example 5

[0106] This comparative example, compared to Example 1, does not contain entomopathogenic nematode cadavers. During preparation, gallic acid is mixed evenly with artificial feed for the sweet potato weevil to form a paste; a suitable amount of the paste is then coated with a layer of dry trehalose (α,α) powder. All other conditions are the same as in Example 1.

[0107] Experimental Example 1

[0108] This experimental example discloses an experiment using the drug of the present invention to control the sweet potato weevil.

[0109] 1. Test site

[0110] The experimental sweet potato field in Tuanjie Village, Huatan Town, Changning County, Yibin City. This experimental field is located in hilly, dry land, where the sweet potato weevil has caused severe damage. The experiment was repeated three times in a randomized block design, with each plot planted at 30m². 2 Management should be carried out at the same level as in the local area. At harvest, the damage to sweet potato tubers by the small weevil (damage index) and the yield loss (yield loss rate) should be investigated and recorded on a plant-by-plant basis.

[0111] Standards and calculation methods for investigating and calculating the hazards of the baby weevil:

[0112] During the survey, sweet potato tubers with weevil infestation were marked as 1, and those without infestation were marked as 0.

[0113] The classification criteria for damage to tubers by the small weevil are as follows: 0: No disease; 1: Diseased area accounts for 1% to 5% of the total tubers; 3: Diseased area accounts for 5% to 10% of the total tubers; 5: Diseased area accounts for 10% to 20% of the total tubers; 7: Diseased area accounts for 20% to 50% of the total tubers; 9: Diseased area accounts for more than 50% of the total tubers.

[0114] The formula for calculating the harm index of the baby weevil is as follows:

[0115] Harm Index (%) = [(1×C1+3×C3+5×C5+7×C7+9×C9) / Total number of tubers×9]×100%; where 1, 3, 5, 7, and 9 represent the levels of damage (tubers) caused by the small weevil, and C1 to C9 represent the number of tubers damaged by the small weevil at each level.

[0116] The formula for calculating the damage rate is as follows:

[0117] Damage rate (%) = Number of damaged tubers / Total number of tubers surveyed × 100%

[0118] The formula for calculating the prevention and control effect is as follows:

[0119] Control efficacy (%) = (Damage rate in control area - Damage rate in treatment area) / Damage rate in control area × 100%

[0120] 2. Experimental Design

[0121] The entire group of this invention uses the drug from Example 1 of this invention.

[0122] Treatment 1: The drug used in Comparative Example 1 was used.

[0123] Treatment 2: The drug used in Comparative Example 2 was used.

[0124] Treatment group 3: The drug used in Comparative Example 3 was employed.

[0125] Treatment group 4: The drug used in Comparative Example 4 was employed.

[0126] Treatment group 5: The drug used in control group 5 was employed.

[0127] Blank control group: No medication was administered.

[0128] Conventional control group: 1% bifenthrin·thiamethoxam granules (Yingzhuang) were administered at a rate of 5 kg / 667 m². 2 Apply the mixture evenly to the ridges near the sweet potato plants.

[0129] When planting sweet potatoes, place a compound of insect corpses of entomopathogenic nematodes at the base of the sweet potato seedlings, using 2g of the compound of insect corpses of entomopathogenic nematodes per seedling.

[0130] The sweet potato root protectant is placed in a wash bottle and 20-25 ml is evenly dripped onto the roots of each sweet potato seedling. The dripping area is a circle with a diameter of 10-15 cm centered on the base of the sweet potato seedling roots.

[0131] Blank groups are left unprocessed.

[0132] The conventional control group's control method was: using 1% bifenthrin·thiamethoxam granules (Yingzhuang) at a rate of 5 kg / 667 m². 2 Apply the mixture evenly to the ridges near the sweet potato plants.

[0133] The results are shown in the table below:

[0134] Table 1 Results of the Sweet Potato Weevil Control Trial

[0135] Group Hazard Index % Harm rate % % efficacy Process 1 group 26.10±1.16cd 20.48±2.75b 50.97±6.56c Treatment 2 groups 27.31±0.83c 18.58±0.17b 55.52±0.40c 3 groups were treated 23.55±0.64de 15.38±2.01c 63.19±4.81b 4 groups were treated 20.93±1.75e 12.40±0.72cd 70.30±1.71ab 5 groups were treated 31.64±2.40b 20.71±2.54b 50.42±6.08c This invention involves grouping all groups. 14.14±1.62f 9.71±1.02d 76.74±2.42a Blank control group 44.63±2.87a 34.43±0.60a / Conventional treatment control group 23.15±2.00de 13.72±1.42c 67.14±3.39b

[0136] The experimental results showed that, although the damage index and damage rate of the treatment without entomopathogenic nematode cadavers (treatment group 5) were lower than those of the blank control group, they were significantly higher than those of the other treatment groups. This indicates that the entomopathogenic nematode cadavers played the most important role in the entire formulation and could effectively reduce the damage of sweet potato weevil larvae to sweet potato tubers. Furthermore, the damage rate of sweet potato weevil without artificial feed for sweet potato weevils and without the polyphenol oxidase inhibitor gallic acid was significantly higher than that of the treatment group containing all the ingredients of the invention. This indicates that artificial feed for sweet potato weevils and polyphenol oxidase inhibitors can significantly improve the control effect of entomopathogenic nematodes on sweet potato weevils, suggesting that artificial feed for sweet potato weevils and gallic acid are indispensable. The damage index of the treatment group without biocontrol agents and sweet potato weevil repellents was significantly higher than that of the treatment group containing all the ingredients of the invention, indicating that biocontrol agents and sweet potato weevil repellents can also improve the protection of sweet potato tubers and are indispensable.

[0137] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An insect pathogenic preparation for controlling Cylas formicarius, characterized by comprising a bacterium belonging to the genus Xenorhabdus and a bacterium belonging to the genus Photorhabdus. The insect cadaver compound agent of insect pathogenic nematode and sweet potato root protection agent are provided; The insect cadaver compound agent of insect pathogenic nematode comprises insect pathogenic nematode cadaver agent, sweet potato small elephant beetle artificial feed, gallic acid and alpha, alpha-trehalose dry powder, and the mass ratio is 1-3:6-8:0.25-0.35:0.6-0.8; The biocontrol agent is 0.03-0.05g, the sweet potato small elephant beetle repellent is 3-5g, and the adhesive is 90-110ml per 1L of the sweet potato root protection agent, and the volume is supplemented with water; the sweet potato small elephant beetle repellent comprises at least one of Zanthoxylum bungeanum, Nepeta catarrh, and Tagetes erecta; the adhesive comprises glutinous rice glue; and the biocontrol agent comprises Beauveria bassiana agent; The preparation method of the insect pathogenic nematode cadaver agent comprises the following steps: taking 4-5 age mature Tenebrio molitor larvae and placing them in a container, and adding the insect pathogenic nematode in the infectious stage into the container; The intact cadaver of the Tenebrio molitor larvae after death is the insect pathogenic nematode cadaver agent; One mature Tenebrio molitor larva is used with 100-400 insect pathogenic nematodes in the infectious stage; The sweet potato small elephant beetle artificial feed is prepared from the following components in parts by weight: 8-12 parts of sweet potato blocky roots, 5-8 parts of sweet potato powder, 1-2 parts of casein, 1-2 parts of cellulose, 3-5 parts of glucose, 3.00-5.26 parts of yeast powder, 7.50-9.78 parts of soybean powder, 4.49-5.64 parts of sucrose, 0.30-0.32 parts of ascorbic acid, 0.060-0.065 parts of cholesterol, 0.02-0.05 parts of methyl p-hydroxybenzoate, 0.04-0.1 parts of potassium sorbate, 0.007-0.008 parts of compound vitamin B, 1.50-2.56 parts of agar, and 70-75 parts of water.

2. The insect pathogenic preparation for controlling Cylas formicarius according to claim 1, characterized by, The mass ratio of the insect pathogenic nematode cadaver agent, the sweet potato small elephant beetle artificial feed, the gallic acid, and the alpha, alpha-trehalose dry powder is 2:7:0.3:0.

7.

3. The entomopathogenic formulation for controlling Cylas formicarius according to claim 1, characterized in that, The biocontrol agent is 0.04g, the sweet potato small elephant beetle repellent is 4g, and the adhesive is 100ml per 1L of the sweet potato root protection agent, and the volume is supplemented with water.

4. The insect pathogenic preparation for controlling Cylas formicarius according to claim 1, characterized by, The sweet potato small elephant beetle artificial feed is prepared from the following components in parts by weight: 10 parts of sweet potato blocky roots, 6.5 parts of sweet potato powder, 1.5 parts of casein, 1.5 parts of cellulose, 4 parts of glucose, 4.13 parts of yeast powder, 8.6 parts of soybean powder, 5.06 parts of sucrose, 0.31 parts of ascorbic acid, 0.062 parts of cholesterol, 0.035 parts of methyl p-hydroxybenzoate, 0.07 parts of potassium sorbate, 0.007 parts of compound vitamin B, 2.03 parts of agar, and 72.5 parts of water.

5. The method for preparing the insect pathogenic preparation for preventing and treating Lasiomala vittata according to any one of claims 1 to 4, characterized in that, The insect cadaver compound agent of insect pathogenic nematode and sweet potato root protection agent are provided; S1. Preparing the sweet potato small elephant beetle artificial feed: treating the sweet potato blocky roots into a paste, mixing the rest components uniformly to obtain a paste-like mixture, sterilizing to obtain the sweet potato small elephant beetle artificial feed; S2. Mixing the polyphenol oxidase inhibitor and the sweet potato small elephant beetle artificial feed uniformly to form a paste. S3. The insect pathogenic nematode cadaver agent is wrapped with the mud paste prepared in step S2; and then wrapped with a layer of dry powder added with α, α-trehalose to obtain an insect pathogenic nematode cadaver compound agent; The preparation method of the sweet potato root protection agent comprises the following steps: crushing the sweet potato weevil repellent into powder, uniformly mixing the sweet potato weevil repellent with glutinous rice glue and Beauveria bassiana agent, and adding water to form a hydrogel, so that the sweet potato root protection agent is obtained.

6. The use of the insect pathogenic agent according to any one of claims 1-4 in the prevention and treatment of sweet potato weevils.

7. A method of controlling Cylas formosanus in sweet potato, characterized by, The insect pathogenic agent according to any one of claims 1-4 is adopted.

8. The method of claim 7, wherein, When the sweet potatoes are sowed, the sweet potato weevil repellent is placed in the root of the sweet potato seedling, and the sweet potato root protection agent is uniformly dripped on the root of the sweet potato seedling.

9. The method of claim 8, wherein, The dosage of the sweet potato root protection agent is 20-25 ml per seedling.

10. The method of claim 8, wherein, The dripping area is a range with a diameter of 10-15 cm and the sweet potato seedling root base as the center.