A large-scale production device for Meteorus pulchricornis and its production method

Abstract

The present invention discloses a large-scale production device for Meteorus pulchricornis and its production method. The device includes, from top to bottom: a lid provided with a first screen; an upper box with an open top that mates with the lid and a second screen at the bottom; and a lower box with an open top that mates with the bottom of the upper box. According to the phototactic and upward tropic behaviors and the behavior characteristics of ventral clutching parasitism of Meteorus pulchricornis, the present invention designs a method of relatively isolating the host and the parasitoid above and below respectively by using a screen with a certain mesh number, so that the ovipositor of Meteorus pulchricornis can pierce through the mesh holes to reach the host and complete the oviposition behavior. This is beneficial to quickly separating the host and the parasitoid, and quickly transferring the host from the parasitism box to the breeding box, greatly improving the working efficiency during the parasitism process.

Description

Technical Field

[0001] The present invention relates to the technical field of the production of Meteorus pulchricornis, and particularly relates to a large-scale production device for Meteorus pulchricornis and a production method thereof. Background Art

[0002] Pests of the family Noctuidae (Lepidoptera) are widely distributed in various countries and regions. Among them, for example, Spodoptera litura Spodoptera litura Fabricius , Spodoptera frugiperda Spodoptera frugiperda , Spodoptera exigua Spodoptera exigua and Mythimna separata Mythimna separata etc. are malignant agricultural pests distributed worldwide, with characteristics such as omnivorous feeding habits, strong reproductive ability, and great destructiveness. The larvae biting plants can cause holes or notches in the plant leaves, and in severe cases, cause the death of the plants. In China, vegetables, fruits, rice, and garden plants in most regions have been damaged by Noctuidae, especially Spodoptera litura and Spodoptera exigua, causing huge economic losses and serious social impacts on agricultural production.

[0003] At present, the methods for controlling Noctuidae pests still mainly rely on chemical control. However, the long-term use of chemical pesticides has led to increasingly serious problems such as excessive pesticide residues in agricultural products, enhanced pest resistance to pesticides, and damage to the ecological balance. Biological control means, especially the control of pests by natural enemies, is a green and safe pest control method. As natural enemies of pests, parasitic wasps are an important biological control resource. After being mass-reproduced, they can be used as biological pesticide products for green control of pests, and have great application value.

[0004] Meteorus pulchricornis Meteorus pulchricornis belongs to the family Braconidae (Hymenoptera). This wasp is widely distributed in the Palaearctic region and is mainly distributed in 10 provinces in East China, Central China, North China, and Southwest China in China. The population in Europe reproduces sexually, while the Asian population reproduces parthenogenetically. This wasp is an endoparasitic wasp in insects and is a facultative parasitic wasp with a relatively wide host range. It is a dominant parasitic wasp of pests such as Spodoptera litura, Spodoptera frugiperda, Spodoptera exigua, and Mythimna separata. After parasitizing the host, it can cause the host's food intake to rapidly decrease and eventually die, greatly reducing the damage of pests to host plants. Therefore, Meteorus pulchricornis has high biological control potential, broad application prospects, and is beneficial to the quality safety of agricultural products and the ecological environment safety.

[0005] At present, although there are some studies and reports on the basic biology and ecology of Meteorus pulchricornis at home and abroad, due to reasons such as space, efficiency, and key technical difficulties that have not been overcome, only small-scale populations can be propagated in the laboratory. There is still no research and patent on the large-scale production technology of Meteorus pulchricornis, which has hindered the application of this wasp in pest biological control. Therefore, it is particularly important to study the large-scale production method of this wasp. SUMMARY OF THE INVENTION

[0006] In view of this, the object of the present invention is to provide a large-scale production device for Meteorus pulchricornis and its production method, which can solve at least one technical problem mentioned in the background art.

[0007] According to one aspect of the present invention, there is provided a large-scale production device for Meteorus pulchricornis, which includes from top to bottom:

[0008] A lid provided with a first screen.

[0009] An upper box with an open top that mates with the lid and a second screen at the bottom.

[0010] A lower box with an open top that mates with the bottom of the upper box.

[0011] In the above technical solution, according to the phototactic and upward taxis behaviors and the ventral parasitism behavior characteristics of Meteorus pulchricornis, a method is designed to relatively isolate the host and the parasitic wasp above and below respectively by using a screen with a certain mesh number, so that the ovipositor of Meteorus pulchricornis can pierce through the mesh holes to reach the host and complete the oviposition behavior. This is beneficial to quickly separate the host and the parasitic wasp, and quickly transfer the host from the parasitic box to the breeding box, greatly improving the working efficiency during the parasitism process.

[0012] In some embodiments, the mesh number of the first screen is 90 - 110 meshes; the mesh number of the second screen is 20 - 25 meshes; both the upper box and the lower box are made of transparent materials; and round holes are provided on the wall surface of the lower box.

[0013] In the above technical solution, in order to further improve the working efficiency during the parasitism process, according to the parasitic habits, a screen with a specific mesh number is further used to relatively isolate the host and the parasitic wasp above and below respectively.

[0014] In some embodiments, the production device further includes a middle box;

[0015] A middle box with an open top that mates with the bottom of the upper box, a third screen is provided at the bottom of the middle box, and it mates with the lower box.

[0016] In the above technical solution, according to the phototactic and upward taxis behaviors and the behavior characteristics of ventral parasitism of Meteorus pulchricornis, a method is designed to relatively isolate the host and the parasitic wasp above and below respectively by using a screen mesh with a certain mesh number, so that the ovipositor of Meteorus pulchricornis can pierce through the mesh holes to reach the host and complete the oviposition behavior. This is beneficial to quickly separate the host and the parasitic wasp, and quickly transfer the host from the parasitic box to the breeding box, greatly improving the working efficiency during the parasitism process. On this basis, according to the characteristics that the unparasitized host has a larger developmental size, the parasitized host has a smaller developmental size, and the larva of the parasitic wasp has an even smaller size, an intermediate layer box is further set up, which helps to reduce the probability of the cocoons being eaten by others and improve the working efficiency during the cocoon collection process.

[0017] In some embodiments, the mesh number of the first screen mesh is 90 - 110 meshes; the mesh number of the second screen mesh is 3 - 7 meshes; the mesh number of the third screen mesh is 5 - 10 meshes; the intermediate layer box is made of a transparent material.

[0018] In the above technical solution, in order to further reduce the probability of the cocoons being eaten by others and improve the working efficiency during the cocoon collection process, according to the characteristics that the unparasitized host has a larger developmental size, the parasitized host has a smaller developmental size, and the larva of the parasitic wasp has an even smaller size, the unparasitized host is isolated above the 3 - 7 mesh sieve of the upper layer box, the parasitized host is isolated above the 5 - 10 mesh sieve of the intermediate layer box, and the larva of the parasitic wasp climbs down through the mesh holes of the 5 - 10 mesh sieve of the intermediate layer box and pupates in the space of the lower layer box.

[0019] According to another aspect of the present invention, there is provided a method for large - scale production of Meteorus pulchricornis, including:

[0020] S1. Move the cocoons about to emerge into adult wasps into the lower layer box of the first production device, and plug the round holes of the lower layer box with absorbent cotton balls; after the parasitic wasps emerge, put absorbent cotton balls soaked in 10% honey water into the round holes of the lower layer box, and change the honey water once a day;

[0021] S2. Within the 1st to 10th days after the parasitic wasps emerge, change the host for them once a day to complete continuous parasitism;

[0022] S3. Transfer the parasitized host to a breeding tray for continued breeding;

[0023] S4. When the parasitized host is raised to the 7th - 8th day, transfer it to the second production device;

[0024] S5. On the 10th - 11th day after parasitism, collect the cocoons;

[0025] S6. One day before the cocoons collected emerge, transfer the cocoons to the lower layer box of the first production device and wait for them to emerge;

[0026] S7. Repeat steps S1 - S7 to complete the successive propagation of Meteorus pulchricornis.

[0027] In the above technical solution, according to the phototactic and upward-tropic behaviors and the abdominal-hugging parasitic behavior characteristics of Meteorus pulchricornis, a method is designed to relatively isolate the host and the parasitic wasp above and below respectively by using a screen mesh with a certain mesh number, so that the ovipositor of Meteorus pulchricornis can pierce through the mesh holes to reach the host and complete the oviposition behavior. This is beneficial to quickly separate the host and the parasitic wasp, and quickly transfer the host from the parasitic box to the rearing box, greatly improving the working efficiency during the parasitism process.

[0028] In some embodiments, in S2, within the first 1 - 10 days after the parasitic wasps emerge, the host is replaced for them once a day to complete continuous parasitism. Specifically:

[0029] The host is placed above the second screen mesh in the upper layer box of the first production device. The parasitic wasps in the lower layer box attach their feet to the lower surface of the second screen mesh and pierce the ovipositor into the host body through the mesh holes of the second screen mesh to lay eggs, completing the parasitism behavior.

[0030] In the above technical solution, the second screen mesh can separate the host and the parasitic wasps in the upper and lower layers respectively without affecting the parasitism behavior.

[0031] In some embodiments, the parasitism ratio of providing hosts for the parasitic wasps in S2 is: on the 1st day: 1:3 - 5; on the 2nd day: 1:6 - 10; on the 3rd to 10th days: 1:11 - 20.

[0032] In the above technical solution, according to the parasitism rhythm of Meteorus pulchricornis (the effective parasitism amount on the same day first increases and then decreases with the age) and characteristics such as having parasitic experience (compared with each other, parasitic wasps with parasitic experience have higher parasitic efficiency), the parasitism ratio provided daily has a certain gradient change, so as to reduce the waste ratio of hosts during the propagation and production process of parasitic wasps.

[0033] In some embodiments, in S4, the parasitized host is reared until the 7th - 8th day and then transferred to the second production device. Specifically:

[0034] Transfer the host above the second screen mesh of the second production device;

[0035] The unparasitized and parasitized hosts are automatically screened by the second screen mesh into the upper layer box and the middle layer box respectively;

[0036] On the 9th - 10th day after the host is parasitized, the cocoons of the parasitic wasps are automatically screened into the lower layer box.

[0037] In the above technical solution, during the group rearing process of the host, there will be certain self-harming behaviors when it grows to the late larval stage. In particular, the unparasitized host (larger in size) will bite and kill the parasitized host (smaller in size) and the cocoons newly emerged by the parasitoid wasps. Therefore, a second screen is provided to automatically separate the parasitized and unparasitized hosts.

[0038] In some embodiments, on the 10th - 11th day after parasitization, collect the cocoons. Specifically:

[0039] When the middle box is lifted separately, it can be seen that the cocoons are suspended below the third screen by the cocoon silk. Cut the cocoon silk with scissors to collect the cocoons into a container.

[0040] In the above technical solution, if the parasitized host is continuously reared in the rearing tray without using a large-scale production device for Meteorus pulchricornis, after the parasitoid wasps emerge from the cocoons, the cocoon silk is entangled in a disorderly manner, resulting in extremely low efficiency in collecting cocoons. When using a large-scale production device for Meteorus pulchricornis, the suspended cocoons can be taken out by using the third screen, greatly improving the efficiency of collecting cocoons. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0042] Figure 1 is a schematic structural diagram of one of the embodiments of the large-scale production device for Meteorus pulchricornis of the present invention in a disassembled state;

[0043] Figure 2 is a three-dimensional schematic diagram of one of the embodiments of the large-scale production device for Meteorus pulchricornis of the present invention in a disassembled state;

[0044] Figure 3 is a schematic structural diagram of one of the embodiments of the large-scale production device for Meteorus pulchricornis of the present invention in a disassembled state;

[0045] Figure 4 is a three-dimensional schematic diagram of one of the embodiments of the large-scale production device for Meteorus pulchricornis of the present invention in a disassembled state;

[0046] Figure 5 is a schematic flow diagram of an embodiment of the large-scale production method for Meteorus pulchricornis of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0047] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be specifically noted that the following embodiments are only used to illustrate the present invention, but do not limit the scope of the present invention. Similarly, the following embodiments are only partial embodiments of the present invention rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0048] The object of the present invention is to provide a large-scale production device and production method for Meteorus pulchricornis, which can solve at least one technical problem mentioned in the background art.

[0049] Embodiment 1

[0050] Please refer to Figure 1 、 Figure 2 , a large-scale production device 1 for Meteorus pulchricornis, including from top to bottom:

[0051] A lid 12 provided with a first screen 11;

[0052] An upper box 13, the top of which is open and mates with the lid 12, and a second screen 14 is provided at the bottom;

[0053] A lower box 15, the top of which is open and mates with the bottom of the upper box 13.

[0054] In this embodiment, according to the phototactic and upward tropic behaviors and the ventral parasitism behavior characteristics of Meteorus pulchricornis, a method is designed to relatively isolate the host and the parasitic wasp above and below respectively by using a screen with a certain mesh number, so that the ovipositor of Meteorus pulchricornis can pierce through the mesh holes to reach the host and complete the oviposition behavior. This is beneficial to quickly separate the host and the parasitic wasp, and quickly transfer the host from the parasitic box to the breeding box, greatly improving the working efficiency during the parasitism process.

[0055] In this embodiment, in order to further improve the working efficiency during the parasitism process, according to the parasitism rhythm, a screen with a specific mesh number is further used to relatively isolate the host and the parasitic wasp above and below respectively. The mesh number of the first screen 11 is 90 - 110 meshes; the mesh number of the second screen 12 is 20 - 25 meshes; both the upper box 13 and the lower box 15 are made of transparent materials; circular holes 16 are provided on the wall surface of the lower box 15. As a preferred solution, the mesh number of the first screen 11 is 100 - mesh screen, which can ensure air permeability; the mesh number of the second screen is 24 meshes, which can ensure that the host and the parasitic wasp can be separated into the upper and lower layers respectively without affecting the parasitism behavior.

[0056] In this embodiment, as a specific solution, the specific parameters are as follows:

[0057] The device in this embodiment is a cuboid double-layer box structure made of transparent material, mainly composed of a lid, an upper box (4 cm high), and a lower box (6 cm high). The three parts can be detachably and fixedly stacked together in sequence from top to bottom. Specifically, an existing quick-release connection mechanism can be used for detachable connection, such as a buckle. The detachable connection of each part is completed by buckling the buckle. Preferably, the length and width of the three parts are both 30 cm and 20 cm.

[0058] ① Lid 12: A 100-mesh first screen with a side length of 5 cm is opened at the middle position to ensure air permeability.

[0059] ② Upper box 13: The upper part is open, the lower part is a 24-mesh second screen, and the other four sides are made of transparent material.

[0060] ③ Lower box 14: The upper part is open, the other five sides are all made of transparent material, and there is a circular hole 16 with a diameter of 3 cm at the middle position near the bottom of the front side.

[0061] Embodiment 2

[0062] Please refer to Figure 3 、 Figure 4 A large-scale production device 2 for Meteorus pulchricornis, comprising:

[0063] A lid 22, and the lid is provided with a first screen 21;

[0064] An upper box 23, the top of the upper box 23 is open and matches the lid 22, and the bottom is provided with a second screen 24;

[0065] A middle box 25, the top of the middle box 25 is open and matches the bottom of the upper box 23, and the bottom of the middle box 25 is provided with a third screen 26.

[0066] A lower box 27, the top of the lower box 27 is open and matches the bottom of the middle box 25.

[0067] In this embodiment, according to the phototactic and upward-tropic behaviors and the behavior characteristics of ventral parasitism of Meteorus pulchricornis, a method is designed to relatively isolate the host and the parasitoid wasp above and below respectively by using a screen mesh with a certain mesh number, so that the ovipositor of Meteorus pulchricornis can pierce through the mesh holes to reach the host and complete the oviposition behavior. This is beneficial to quickly separate the host and the parasitoid wasp, and quickly transfer the host from the parasitism box to the breeding box, greatly improving the work efficiency during the parasitism operation. On this basis, according to the parasitism rhythm of Meteorus pulchricornis (if the parasitized host is always raised in a breeding tray and a large-scale production device for a certain kind of Meteorus pulchricornis is not used, after the parasitoid wasp emerges from the cocoon, the cocoon silk is randomly entangled together, resulting in extremely low work efficiency for cocoon collection; if the parasitized host is always raised in a breeding tray and a large-scale production device for a certain kind of Meteorus pulchricornis is not used, after the parasitoid wasp emerges from the cocoon, the cocoon silk is randomly entangled together, resulting in extremely low work efficiency for cocoon collection;), a middle layer box is further set up, which helps to reduce the probability of the wasp cocoons being eaten by predators and improve the work efficiency during the cocoon collection process.

[0068] In this embodiment, in order to further improve the work efficiency during the parasitism process, according to the parasitism rhythm, the host and the parasitoid wasp are relatively isolated respectively by using a screen mesh with specific mesh numbers. The mesh number of the first screen mesh 21 is 90 - 110 meshes; the mesh number of the second screen mesh 24 is 3 - 7 meshes; the mesh number of the third screen mesh 26 is 5 - 10 meshes; the middle layer box 25 is made of transparent material. As a preferred solution, the mesh number of the first screen mesh 21 is 100-mesh sieve, which can ensure air permeability; the mesh number of the second screen mesh 24 is 5 meshes. The purpose of such setting is that the parasitized host, due to its relatively small developmental individual, can climb from the upper box 23 to the lower box 27 through the 5-mesh holes; while the unparasitized Mythimna separata, due to its relatively large developmental individual, cannot pass through the 5-mesh holes and is separated in the upper box 23. The mesh number of the third screen mesh 26 is 8 meshes. The purpose of such setting is that when the parasitoid wasp larvae climb to the lower box 27, one end of the cocoon silk can adhere to a certain site on the surface of the 8-mesh nylon net and form a cocoon in the lower box 27. At the same time, after the parasitoid wasp larvae drill out of the host body surface, because of their smaller volume, they can climb from the 8-mesh holes on the middle layer box 25 to the lower box 27.

[0069] In this embodiment, as a specific solution, the specific parameters are as follows:

[0070] The device of this embodiment is a cuboid device composed of a top cover (including a lid and a 100-mesh first screen mesh with a side length of 6 cm), an upper sieve box (wrapping the upper box and a 5-mesh second screen mesh, with a height of 6 cm), a middle sieve box (including the middle layer box and an 8-mesh third screen mesh, with a height of 6 cm) and a lower box (with a height of 3 cm). The four parts can be buckled tightly in sequence from top to bottom, and the length and width of the four parts are 40 cm and 30 cm.

[0071] Example Three

[0072] Please refer toFigure 5 , a large-scale production method of Meteorus pulchricornis, which is carried out based on the devices of Example 1 and Example 2. The specific steps include the following steps:

[0073] S1. Transfer the cocoons of wasps that are about to emerge into adult wasps into the lower box of a large-scale production device for Meteorus pulchricornis in Example 1, and plug the round holes of the lower box with absorbent cotton balls; after the parasitic wasps emerge, put absorbent cotton balls soaked in 10% honey water into the round holes of the lower box, and change the honey water once a day;

[0074] S2. Within the 1st to 10th days after the parasitic wasps emerge, change the host for them once a day to complete continuous parasitism;

[0075] S3. Transfer the parasitized hosts to a feeding tray for continued feeding;

[0076] S4. When the parasitized hosts are raised to the 7th - 8th day, transfer them to a large-scale production device for Meteorus pulchricornis in Example 2;

[0077] S5. On the 10th - 11th day after parasitism, collect the cocoons;

[0078] S6. One day before the cocoons collected emerge, transfer the cocoons to the lower box of a large-scale production device for Meteorus pulchricornis in Example 1 and wait for them to emerge;

[0079] S7. Repeat steps S1 - S7 to complete the successive propagation of Meteorus pulchricornis.

[0080] In this embodiment, according to the phototactic and upward taxis behaviors and the ventral - clutching parasitism behavior characteristics of Meteorus pulchricornis, a method is designed to relatively isolate the host and the parasitic wasp above and below respectively by using a screen with a certain mesh number, so that the ovipositor of Meteorus pulchricornis can pierce through the mesh holes to reach the host and complete the oviposition behavior. This is beneficial to quickly separate the host and the parasitic wasp, and quickly transfer the host from the parasitic box to the feeding box, greatly improving the working efficiency during the parasitism process.

[0081] In this embodiment, in S2, within the 1st to 10th days after the parasitic wasps emerge, change the host for them once a day to complete continuous parasitism. Specifically: the host is placed on the second screen of the upper box of a large-scale production device for Meteorus pulchricornis in Example 1, and the parasitic wasps in the lower box attach to the lower surface of the second screen with their feet, and pierce the ovipositor into the host body through the mesh holes of the second screen to lay eggs and complete the parasitism behavior. The second screen can separate the host and the parasitic wasp in the upper and lower layers respectively without affecting the parasitism behavior.

[0082] In this embodiment, the parasitism ratio of providing hosts for parasitoid wasps in S2 is as follows: on the 1st day: 1:3 - 5; on the 2nd day: 1:6 - 10; on the 3rd to 10th days: 1:11 - 20. According to the parasitism rhythm of Meteorus pulchricornis (the effective parasitism amount on the same day first increases and then decreases with the age) and characteristics such as having parasitism experience (compared with that, parasitoid wasps with parasitism experience have higher parasitism efficiency), there is a certain gradient change in the parasitism ratio provided daily, so as to reduce the waste ratio of hosts during the process of mass rearing of parasitoid wasps.

[0083] In this embodiment, in S4, the hosts after parasitism are reared until the 7th - 8th day, and then transferred to a large-scale production device for Meteorus pulchricornis in Embodiment Two. Specifically: the hosts are transferred onto the second screen of the large-scale production device for Meteorus pulchricornis in Embodiment Two; the unparasitized and parasitized hosts are automatically screened by the second screen to the upper box and the middle box respectively; on the 9th - 10th day after the hosts are parasitized, the parasitoid wasp cocoons are automatically screened to the lower box. Since during the group rearing of hosts, there will be certain self-harm behaviors when they grow to the late larval stage, especially the unparasitized hosts (larger in size) will bite the parasitized hosts (smaller in size) and the newly emerged cocoons of parasitoid wasps to death; therefore, the second screen is set to automatically separate the parasitized and unparasitized hosts.

[0084] In this embodiment, in S5, on the 10th - 11th day after parasitism, the cocoons are collected. Specifically: when the middle box is lifted alone, it can be seen that the cocoons are suspended below the third screen by cocoon silk, and the cocoons are collected into a container by cutting the cocoon silk with scissors. In the above technical solution, if the hosts after parasitism are always reared in the rearing tray without using a large-scale production device for Meteorus pulchricornis, after the parasitoid wasps emerge from the cocoons, the cocoon silk is entangled in a disorderly manner, resulting in extremely low efficiency of cocoon collection; in the case of using a large-scale production device for Meteorus pulchricornis, the suspended cocoons can be taken out by using the third screen, greatly improving the efficiency of cocoon collection.

[0085] In this embodiment, the rearing tray is a transparent plastic tray with a lid, and there are two screen ventilation openings on the lid, with dimensions of 42 * 30 * 5 cm.

[0086] In this embodiment, as a specific scheme, it is as follows:

[0087] The entire rearing process is carried out in an artificial climate chamber, with a light-dark cycle of 14:10, a temperature of 25 - 27 °C, and a humidity of 50 - 70%. The steps are as follows:

[0088] (1) Considering that the cocoons begin to emerge as adult wasps on the 6th day of cocoon formation, the cocoons cultured to the 5th day are transferred into the lower box of Embodiment One, and the round holes of the lower box are plugged with absorbent cotton balls.

[0089] After the parasitic wasps emerge, absorbent cotton balls soaked in 10% honey water are placed into the lower box through the round holes, and the honey water is changed daily.

[0090] (2)Within the first 10 days after the parasitic wasps emerge, the host (taking Mythimna separata as an example) is changed daily for them to complete continuous parasitism.

[0091] The instar of Mythimna separata provided as the host for the parasitic wasps is from the end of the 2nd instar to the beginning of the 3rd instar, and the parasitism time is 20 - 24 hours.

[0092] The parasitism ratio of Mythimna separata provided as the host for the parasitic wasps is: 1:(3 - 5) on the first day, 1:(6 - 10) on the second day, and 1:(11 - 20) on the 3rd - 10th days.

[0093] The Mythimna separata host is placed on the 24 - mesh second gauze of the upper box in one of the examples. The parasitic wasps in the lower box attach to the lower surface of the second gauze through their feet, and insert their ovipositors into the Mythimna separata through the mesh holes of the second gauze to lay eggs, completing the parasitism behavior. The second gauze with a certain range (20 - 30) of mesh numbers can separate the host and the parasitic wasps in the upper and lower layers respectively without affecting the parasitism behavior.

[0094] (3)The parasitized Mythimna separata host is transferred to a feeding tray for continued feeding.

[0095] The way to transfer the Mythimna separata to the feeding tray is to remove the lid of one of the examples. When the upper box and the lower box are tightly fastened, turn them upside down. The parasitized Mythimna separata in the upper box can fall into the feeding tray by gently brushing with a writing brush.

[0096] The artificial feed is supplemented for the parasitized Mythimna separata in the feeding tray every 1 - 2 days.

[0097] (4)The parasitized Mythimna separata host is raised until the 7th - 8th day and then transferred to the device of Example 2.

[0098] The parasitized Mythimna separata host is transferred onto the 5 - mesh second gauze of the upper box in Example 2.

[0099] The unparasitized and parasitized Mythimna separata hosts are automatically screened by the 5 - mesh second gauze into the upper box and the middle box respectively (it means that the parasitized Mythimna separata can climb from the upper sieve box to the lower sieve box through the 5 - mesh holes due to its smaller developmental size; while the unparasitized Mythimna separata is separated in the upper sieve box because its developmental size is larger and it cannot pass through the 5 - mesh holes).

[0100] On the 9th - 10th day after the Mythimna separata host is parasitized, the cocoons of the parasitic wasps are automatically screened by the third gauze into the lower box (it means that after the parasitic wasp larvae drill out of the host body surface, they can climb from the 8 - mesh holes on the middle box to the lower box due to their smaller volume).

[0101] (5)On the 10th - 11th day after parasitism, the cocoons are collected from the device of Example 2.

[0102] The method of collecting the bee cocoons is as follows: (During the process of the parasitic wasp larvae crawling down to the lower box, one end of the cocoon silk is adhered to a certain site on the surface of the third 8-mesh screen, and cocoons are formed in the lower box). When the middle box is lifted separately, it can be seen that the bee cocoons are suspended below the third 8-mesh screen of the middle box through the cocoon silk. The bee cocoons are collected into a container by cutting the cocoon silk with scissors.

[0103] On the 5th day after cocoon collection (one day before the bee cocoons emerge), the bee cocoons are transferred to the lower box of one of the embodiments and wait for them to emerge.

[0104] (7) Repeat steps (1)-(6) to complete the successive propagation of Meteorus pulchricornis.

[0105] In order to verify the advancement of this embodiment, the following comparative tests were carried out:

[0106] The breeding environment and basic step parameters are as follows:

[0107] (1) Breeding environment: In the artificial climate chamber, the light time is set to 14 h, the dark time is 10 h, the temperature is 26 °C, and the humidity is 60%.

[0108] (2) Rearing of the host: After the sticky eggs hatch in the rearing box, artificial feed is provided for rearing. When they develop to the end of the 2nd instar to the beginning of the 3rd instar, they can be provided for the parasitic wasps to parasitize.

[0109] (3) Rearing of the parasitic wasps: When the parasitic wasps do not parasitize, they are reared in the parasitic wasp rearing box, and the absorbent cotton balls soaked in 10% honey water are replaced once a day to provide them with a source of nutrition; when the parasitic wasps need to parasitize, the bee cocoons about to emerge are placed in the lower box of one of the embodiments for rearing, and the absorbent cotton balls soaked in 10% honey water are replaced once a day for them.

[0110] (4) Parasitic process: A quantitative amount of Mythimna separata hosts are placed on the 24-mesh nylon net on the upper box of one of the embodiments, and after covering the lid and parasitizing for 20-24 hours, a new Mythimna separata host is replaced for continuous parasitization.

[0111] (5) Rearing of the host after parasitization: The Mythimna separata hosts transferred from the parasitic box to the rearing box are supplemented with artificial feed every 1-2 days for their development.

[0112] (6) Treatment for the parasitic wasps to form cocoons: When the Mythimna separata hosts after parasitization are reared to the 7th-8th day, the Mythimna separata hosts in the rearing box are transferred to the upper box of the second embodiment, and finally the parasitic wasps successfully form cocoons in the space of the lower box.

[0113] (7) Collection of the bee cocoons of the parasitic wasps: On the 10th-11th day after parasitization, the middle box is lifted separately, and the cocoon silk suspended below the third screen of the middle box is cut with scissors, and finally the bee cocoons are collected into a container.

[0114] Test Example 1

[0115] Parasitization operation: 30 pupating bee cocoons were placed in the lower box of one of the embodiments. After all of them emerged as adults, the ratio of host insects (armyworms) to wasps provided for the parasitoid wasps was: 1:4 (120 armyworms) on the first day, 1:8 (240 armyworms) on the second day, and 1:15 (450 armyworms) from the third to the tenth day. Parasitization was carried out for 24 hours every day.

[0116] This treatment was repeated 6 times, and finally the cocoons were collected for processing, and the data were recorded. The parasitization results are shown below.

[0117] Table 1 Parasitization amount and parasitization rate of parasitoid wasps in the treatment of Test Example 1

[0118]

[0119] Test Example 2

[0120] Parasitization operation: 50 pupating bee cocoons were placed in the lower box of one of the embodiments. After all of them emerged as adults, the ratio of host insects (armyworms) to wasps provided for the parasitoid wasps was: 1:5 (250 armyworms) on the first day, 1:10 (500 armyworms) on the second day, and 1:15 (750 armyworms) from the third to the tenth day. Parasitization was carried out for 24 hours every day.

[0121] This treatment was repeated 4 times, and finally the cocoons were collected for processing, and the data were recorded. The parasitization results are shown below.

[0122] Table 2 Parasitization amount and parasitization rate of parasitoid wasps in the treatment of Test Example 2

[0123]

[0124] Test Example 3

[0125] Parasitization operation: 80 pupating bee cocoons were placed in the lower box of one of the embodiments. After all of them emerged as adults, the ratio of host insects (armyworms) to wasps provided for the parasitoid wasps was: 1:5 (400 armyworms) on the first day, 1:10 (800 armyworms) on the second day, and 1:15 (1200 armyworms) from the third to the tenth day. Parasitization was carried out for 24 hours every day.

[0126] This treatment was repeated 4 times, and finally the cocoons were collected for processing, and the data were recorded. The parasitization results are shown below.

[0127] Table 3 Parasitization amount and parasitization rate of parasitoid wasps in the treatment of Test Example 3

[0128]

[0129] Comparative Example 1

[0130] Put 30 soon-to-emerge bee cocoons into a common breathable box with dimensions of 30*20*15 cm. After all of them have emerged, the ratio of host insects to parasitic wasps provided for the parasitic wasps is as follows: on the 1st day, it is 1:4 (120 host insects), on the 2nd day, it is 1:8 (240 host insects), and from the 3rd to the 10th day, it is 1:15 (450 host insects), with parasitism for 24 hours every day.

[0131] This treatment was repeated 5 times, and finally, the cocoons were collected and the data was recorded. The parasitism results are shown as follows.

[0132] Table 4 Parasitism amount and parasitism rate of parasitic wasps in the treatment of Comparative Example 1

[0133]

[0134] It can be seen from the comparison of the data in the examples and the comparative examples that there is no obvious difference in the parasitism results obtained by using the device of one of the examples and the common breathable box respectively. The advantage is that when the device of one of the examples and the device of the second example are used in combination, the production efficiency in the mass rearing of Meteorus pulchricornis can be greatly improved and the cost can be saved.

[0135] The present invention has the following beneficial effects:

[0136] 1. According to the phototactic and upward taxis behaviors and the ventral parasitism behavior characteristics of Meteorus pulchricornis, the present invention designs a method of relatively isolating the host and the parasitic wasp above and below respectively by using a sieve mesh (gauze) with a certain mesh number, so that the ovipositor of Meteorus pulchricornis can pierce through the mesh holes to reach the host and complete the oviposition behavior. This is beneficial to quickly separating the host and the parasitic wasp, and quickly transferring the host from the parasitic box to the rearing box, greatly improving the working efficiency during the parasitism process.

[0137] 2. According to the parasitism rhythm of Meteorus pulchricornis (the effective parasitism amount on the same day first increases and then decreases with the age) and the characteristics of having or not having parasitism experience (compared with each other, the parasitic wasps with parasitism experience have higher parasitism efficiency), etc., the parasitic ratio provided every day has a certain gradient change, so as to reduce the waste ratio of the host during the mass rearing of the parasitic wasp.

[0138] 3. Since during the group rearing of the host, there will be a certain self-harm behavior when it grows to the late larval stage, especially the unparasitized host (larger in size) will bite the parasitized host (smaller in size) and the newly emerged bee cocoons of the parasitic wasp to death; and because after the parasitic wasps emerge from the cocoons, the cocoon silk is randomly wound together, resulting in extremely low efficiency in collecting the cocoons. Due to the above two reasons, automatically separating the parasitized and unparasitized hosts, and further automatically separating the bee cocoons and the parasitized hosts will be the only way in the mass rearing of Meteorus pulchricornis. Therefore, a "parasitic wasp cocooning device" was designed to meet the above requirements, greatly improving the survival rate of the bee cocoons and the efficiency of collecting the cocoons.

[0139] The above are only some embodiments of the present invention, and thus do not limit the protection scope of the present invention. Any equivalent device or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall similarly be included in the patent protection scope of the present invention.

Claims

1. A large-scale production method of Meteorus pulchricornis, characterized in that, The method is based on a first production device and a second production device; wherein, the first production device includes, from top to bottom: a lid provided with a first screen; an upper box with an open top that mates with the lid and a second screen at the bottom; a lower box with an open top that mates with the bottom of the upper box; the mesh number of the first screen is 90 - 110 meshes; the mesh number of the second screen is 20 - 25 meshes; on the basis of the first production device, the second production device is provided with a middle box; the middle box has an open top that mates with the bottom of the upper box, and a third screen is provided at the bottom of the middle box and mates with the lower box; in the second production device, the mesh number of the first screen is 90 - 110 meshes; the mesh number of the second screen is 3 - 7 meshes; the mesh number of the third screen is 5 - 10 meshes; S1. Transfer the cocoons of wasps about to emerge as adult wasps into the lower box of the first production device, and plug the round holes of the lower box with absorbent cotton balls; after the parasitoid wasps emerge, put absorbent cotton balls soaked in 10% honey water into the round holes of the lower box, and change the honey water once a day; S2. Within the 1st to 10th days after the parasitoid wasps emerge, change the host for them once a day to complete continuous parasitism; S3. Transfer the parasitized hosts to a breeding tray for continued breeding; S4. When the parasitized hosts are raised to the 7th - 8th day, transfer them to the second production device; S5. On the 10th - 11th day after parasitism, collect the cocoons; S6. One day before the cocoons collected emerge, transfer the cocoons to the lower box of the first production device and wait for them to emerge; S7. Repeat steps S1 - S7 to complete the successive propagation of Meteorus pulchricornis.

2. A large - scale production method of Meteorus pulchricornis as described in claim 1, characterized in that, S2. Within the 1st to 10th days after the parasitoid wasps emerge, change the host for them once a day to complete continuous parasitism. Specifically: The host is placed above the second screen of the upper box of the first production device. The parasitoid wasps in the lower box of the first production device attach to the lower surface of the second screen of the first production device by their legs, and pierce the ovipositor into the host through the mesh holes of the second screen of the first production device to lay eggs, thus completing the parasitism behavior.

3. A large - scale production method of Meteorus pulchricornis as described in claim 1, characterized in that, The parasitism ratio of providing hosts for the parasitoid wasps in S2 is: on the 1st day: 1:3 - 5; on the 2nd day: 1:6 - 10; on the 3rd to 10th days: 1:11 - 20.

4. A large - scale production method of Meteorus pulchricornis as described in claim 1, characterized in that, S4. When the parasitized hosts are raised to the 7th - 8th day, transfer them to the second production device. Specifically: Transfer the hosts to above the second screen of the second production device; The unparasitized and parasitized hosts are automatically screened by the second screen of the second production device into the upper box and the middle box of the second production device respectively; On the 9th - 10th day after the hosts are parasitized, the cocoons of the parasitoid wasps are automatically screened into the lower box of the second production device.

5. A large - scale production method of Meteorus pulchricornis as described in claim 1, characterized in that, S5. On the 10th - 11th day after parasitism, collect the bee cocoons. Specifically: When the middle box of the second production device is lifted separately, it can be seen that the bee cocoons are suspended below the third wire mesh by silk threads. Cut the silk threads with scissors to collect the bee cocoons into a container.

Images