Method for mixed rearing of two aphid parasitoid species

Abstract

The present application belongs to the technical field of artificial propagation of natural enemy insects and biological control of agricultural pests, and discloses a method for mixed feeding of two kinds of aphid parasitic wasps, which mainly has the following technical features: the steps include breeding of host plants, inoculation and propagation of aphids, obtaining and inoculation of two kinds of aphid parasitic wasp eggs, collection of parasitic wasps, removal of impurities, and separation of the two kinds of parasitic wasps. The method for mixed feeding of two kinds of aphid parasitic wasps provided by the present application inoculates two kinds of parasitic natural enemies, i.e. Aphidius gifuensis and Encarsia spp., at different time periods, improves the parasitic efficiency of single wasps, avoids interspecific competition between adult wasps, collects the two kinds of parasitic wasps at the same time, and saves manpower and material resources.

Description

Technical Field

[0001] This invention belongs to the field of artificial breeding of natural enemy insects and biological control of agricultural pests, and particularly relates to a method for mixed rearing of two types of aphid parasitic wasps. Background Technology

[0002] Aphids not only harm crops but also spread viruses, significantly impacting crop yields. The tobacco aphid wasp and the cotton aphid wasp are parasitic natural enemies of various aphids, including the cotton aphid and the peach aphid, and have been used in some countries for cotton aphid control in greenhouse vegetables. Currently, most natural enemy insects are reared individually. Because parasitic wasps prefer to parasitize 2nd-3rd instar nymphs, a large number of 1st instar aphids remain unparasitized. Furthermore, aphids are constantly reproducing, so inoculating with a single natural enemy easily leads to a large number of young aphids remaining unparasitized, resulting in resource waste and low reproductive efficiency. Summary of the Invention

[0003] The technical problem to be solved by this invention is to provide a method for the mixed rearing of two types of aphid parasitic wasps that is quick and effective.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention includes the following steps:

[0005] The first step is the propagation of host plants.

[0006] Fill small seedling pots with potting soil to a height of 4-6 cm, then sow eggplant seeds for seedling cultivation; when the eggplant seedlings are 4-6 cm tall, transplant them into medium-sized seedling trays, spray water regularly, and prepare them for use when the eggplant seedlings have grown to 6-8 leaves.

[0007] Step 2: Aphid Inoculation and Reproduction

[0008] Inoculate with aphids, specifically the peach aphid. Cut infested eggplant leaves into 2cm squares, place them face down on new eggplant plants, 6-8 squares per plant. Place each plant in an insect rearing cage with a 120-mesh screen, maintaining an artificial climate of 20-28℃ and 50-80% humidity. After the aphids have transferred to new eggplant plants, remove the square old leaves. 4-5 days later, when the number of aphids on the new eggplant plants reaches 800-1000 per plant, inoculate with the tobacco aphid parasitic wasp.

[0009] Step 3: Obtaining and inoculating the two types of aphid-parasitic wasps

[0010] Pupae of two parasitic wasps, *Aphidius citrinum* and *Aphidius spp.*, were collected from eggplant vines. Larger, brightly colored individuals were selected and placed in rearing tubes with round holes in the caps, which were then sealed with 100-mesh mesh. The rearing tubes were placed in a constant temperature chamber at 24-26℃ and 60-80% humidity, and the emergence of the pupae was observed daily. Adult *Aphidius citrinum* that emerged within 24 hours were placed in rearing cages at a density of 40-50 wasps per plant. Four days after inoculation with *Aphidius citrinum*, adult *Aphidius spp.* that emerged within 24 hours were inoculated again in the rearing cages at a density of 40-50 wasps per plant. After inoculation, the cages were placed in an artificial climate chamber at a temperature of 25-28℃ and a humidity of 50-80%.

[0011] Step 4: Parasitic wasp collection

[0012] When only white or light brown spherical parasitic pupae appear on the eggplant leaves in the rearing cage, start recording the time and wait for 2-3 days. After a large number of cotton aphid pupae appear, collect them. Pick the leaves with the two parasitic pupae and rinse them with clean water using a pressurized water gun to obtain the two parasitic pupae.

[0013] Step 5: Remove impurities

[0014] The two parasitic wasp pupae that were washed off were rinsed and separated repeatedly to remove the heavier small clods of soil and sand. The two parasitic wasp pupae were then placed on a mesh screen to dry. After 1-2 days, the two parasitic wasp pupae were placed on a 40-mesh sieve to remove the fine impurities. Neither parasitic wasp pupae should fall off.

[0015] Step 6: Separation of the two parasitic wasps

[0016] The pupae of the two parasitic wasps differ in size, with the pupae of *Aphidius cirrhosa* being larger than those of *Aphidius cirrhosa*. The pupae of the two types of wasps were separated by using sieves of different mesh sizes. A 40-mesh sieve was placed at the bottom to prevent the pupae from falling through. 25-mesh and 30-mesh sieves were placed in the middle layers to separate the smaller *Aphidius cirrhosa* and *Aphidius cirrhosa* pupae. A 20-mesh sieve was placed at the top to separate the larger *Aphidius cirrhosa* pupae. The pupae were sieved sequentially from top to bottom. First, both types of pupae were placed on the top sieve and sieved twice. The larger *Aphidius cirrhosa* pupae remained on the top sieve, while the smaller *Aphidius cirrhosa* and *Aphidius cirrhosa* pupae fell through the 25-mesh and 30-mesh sieves. Then, the pupae were sieved 2-3 times through the two mesh sieves in the middle layer, from highest to lowest. The *Aphidius cirrhosa* pupae remained on the middle sieve, while the *Aphidius cirrhosa* pupae fell through the 40-mesh sieve at the bottom. In this way, the pupae of the two types of parasitic wasps were separated and collected separately for later use.

[0017] Its additional technical features are as follows: the small nutrient pot is a cylindrical shape with a diameter of 8 cm and a height of 7.5 cm; the medium-sized seedling pot is a cylindrical shape with a diameter of 12 cm and a height of 7.5 cm; the insect rearing cage is 50 cm long, 50 cm wide, and 50 cm high; the insect rearing tube has a diameter of 2.5 cm and a height of 8 cm; the diameter of the round hole in the cover of the insect rearing tube is 1.5 cm; and the rated flow rate of the pressurized water gun is 2.4 m³ / h. 3 / h, power 0.75kW.

[0018] This invention provides a method for mixed rearing of two types of aphid parasitic wasps. Two parasitic natural enemies, *Aphidius cirrhosa* and *Aphidius maculatus*, are inoculated at different time periods, with an interval of 4 days between inoculation. This avoids interspecific competition between the two parasitic wasps and improves the parasitism efficiency of a single species. Inoculation at different time periods also avoids interspecific competition between adult wasps. The pupae of the two parasitic wasps differ in size, and they are separated using sieves with different mesh sizes. Furthermore, both types of parasitic wasps can be collected simultaneously, saving manpower and resources. Because the developmental periods from egg to aphid stage differ between the two parasitic wasps—*Aphidius cirrhosa*'s development is about 2 days longer than *Aphidius maculatus*'s (at 25℃, the egg-aphid stage of *Aphidius cirrhosa* is about 7 days, while that of *Aphidius maculatus* is about 5 days—both parasitic wasps can be collected simultaneously after a large number of *Aphidius maculatus* pupae have formed. The present invention provides a method for mixed rearing of two types of aphid parasitic wasps, which can simultaneously obtain two aphid natural enemy products. In future field applications, different aphid parasitic wasps can be selected according to different climatic conditions and aphid occurrence patterns, thereby greatly improving the aphid control effect.

[0019] This invention provides a method for mixed rearing of two types of aphid parasitic wasps. While using eggplant as the host plant, it improves the aphid parasitism rate and saves labor by introducing a method for mixed rearing of two types of aphid parasitic wasps, further enhancing the efficiency of large-scale aphid parasitic wasp reproduction. Given the upper limit of aphid carrying capacity on the host plant, different inoculation times and wasp species are used to improve the aphid parasitism effect, opening up a new way to improve the efficiency of large-scale reproduction of aphid natural enemies. Depending on the requirements, small nutrient pots are cylindrical with a diameter of 8 cm and a height of 7.5 cm; medium-sized seedling trays are cylindrical with a diameter of 12 cm and a height of 7.5 cm; the insect rearing cages are 50 cm long, 50 cm wide, and 50 cm high; the insect rearing tubes are 2.5 cm in diameter and 8 cm high; and the pressurized water gun has a rated flow rate of 2.4 m³ / h. 3 / h, power 0.75kW. Detailed Implementation

[0020] The following describes in further detail the method of mixed rearing of two types of aphid parasitic wasps according to the present invention, with reference to specific embodiments. Example 1

[0021] The present invention discloses a method for mixed rearing of two types of aphid parasitic wasps, comprising the following steps:

[0022] The first step is the propagation of host plants.

[0023] Fill small seedling pots with potting soil to a height of 4 cm, then sow eggplant seeds for seedling cultivation; when the eggplant seedlings are 4 cm tall, transplant them into medium-sized seedling trays, spray water regularly, and prepare them for use when the eggplant seedlings have grown to 6 leaves.

[0024] Step 2: Aphid Inoculation and Reproduction

[0025] Inoculate with aphids, specifically the peach aphid. Cut the leaves of the eggplant vines infested with aphids into squares with sides of 2 cm, and place them face down on new eggplant vines, 6 squares per vine. Place each vine in an insect rearing cage with a 120-mesh screen, maintaining an artificial climate of 20°C and 50% humidity. After the aphids have transferred to new eggplant vines, remove the square old leaves. Four days later, when the number of aphids on the new eggplant vines reaches 800 per vine, inoculate with the tobacco aphid parasitic wasp.

[0026] Step 3: Obtaining and inoculating the two types of aphid-parasitic wasps

[0027] Pupae of two parasitic wasps, *Aphidius citrinum* and *Aphidius spp.*, were collected from eggplant vines. Larger, brightly colored individuals were selected and placed in rearing tubes with round holes in the caps, which were then sealed with 100-mesh mesh. The rearing tubes were placed in a constant temperature chamber at 24°C and 60% humidity, and the emergence of the pupae was observed daily. Adult *Aphidius citrinum* that emerged within 24 hours were placed in rearing cages at a density of 40 wasps per plant. Four days after inoculation with *Aphidius citrinum*, adult *Aphidius spp.* that emerged within 24 hours were inoculated again in the rearing cages at a density of 40 wasps per plant. After inoculation, the cages were placed in an artificial climate chamber at 25°C and 50% humidity.

[0028] Step 4: Parasitic wasp collection

[0029] When only white or light brown spherical parasitic pupae appear on the eggplant leaves in the rearing cage, start recording the time and wait for 2 days. After a large number of cotton aphid pupae appear, collect them. Pick the leaves containing the two parasitic pupae and rinse them with clean water using a pressurized water gun to obtain the two parasitic pupae.

[0030] Step 5: Remove impurities

[0031] The two parasitic wasp pupae that were washed off were rinsed and separated repeatedly to remove the heavier small clods of soil and sand. The two parasitic wasp pupae were then placed on a mesh screen to dry. After one day, the two parasitic wasp pupae were placed on a 40-mesh sieve to remove the fine impurities. Neither of the two parasitic wasp pupae fell off.

[0032] Step 6: Separation of the two parasitic wasps

[0033] The pupae of the two parasitic wasps differ in size, with the pupae of *Aphidius cirrhosa* being larger than those of *Aphidius cirrhosa*. The pupae of the two types of wasps were separated by using sieves of different mesh sizes. A 40-mesh sieve was placed at the bottom to prevent the pupae from falling through. 25-mesh and 30-mesh sieves were placed in the middle layers to separate the smaller *Aphidius cirrhosa* and *Aphidius cirrhosa* pupae. A 20-mesh sieve was placed at the top to separate the larger *Aphidius cirrhosa* pupae. The pupae were sieved sequentially from top to bottom. First, both types of pupae were placed on the top sieve and sieved twice. The larger *Aphidius cirrhosa* pupae remained on the top sieve, while the smaller *Aphidius cirrhosa* and *Aphidius cirrhosa* pupae fell through the 25-mesh and 30-mesh sieves. Then, the pupae were sieved twice more in the middle sieves, from highest to lowest. The *Aphidius cirrhosa* pupae remained on the middle sieve, while the *Aphidius cirrhosa* pupae fell through the 40-mesh sieve at the bottom. In this way, the pupae of the two types of parasitic wasps were separated and collected separately for later use. Example 2

[0034] The present invention discloses a method for mixed rearing of two types of aphid parasitic wasps, comprising the following steps:

[0035] The first step is the propagation of host plants.

[0036] Fill small seedling pots with potting soil to a height of 5 cm, then sow eggplant seeds for seedling cultivation; when the eggplant seedlings are 5 cm tall, transplant them into medium-sized seedling trays, spray water regularly, and prepare them for use when the eggplant seedlings have grown to 7 leaves.

[0037] Step 2: Aphid Inoculation and Reproduction

[0038] Inoculate with aphids, specifically the peach aphid. Cut infested eggplant leaves into 2 cm squares, place them face down on new eggplant plants, 7 squares per plant. Place each plant in an insect rearing cage with a 120-mesh screen, maintaining an artificial climate of 24°C and 65% humidity. After the aphids have transferred to new eggplant plants, remove the square old leaves. 4.5 days later, when the number of aphids on the new eggplant plants reaches 900 per plant, inoculate with the tobacco aphid parasitic wasp.

[0039] Step 3: Obtaining and inoculating the two types of aphid-parasitic wasps

[0040] Pupae of two parasitic wasps, *Aphidius citrinum* and *Aphidius spp.*, were collected from eggplant vines. Larger, brightly colored individuals were selected and placed in rearing tubes with round holes in the caps, which were then sealed with 100-mesh mesh. The rearing tubes were placed in a constant temperature chamber at 25°C and 70% humidity, and the emergence of the pupae was observed daily. Adult *Aphidius citrinum* that emerged within 24 hours were placed in rearing cages at a density of 45 wasps per plant. Four days after inoculation, adult *Aphidius spp.* that emerged within 24 hours were inoculated again in the rearing cages at a density of 45 wasps per plant. After inoculation, the cages were placed in an artificial climate chamber at 26.5°C and 65% humidity.

[0041] Step 4: Parasitic wasp collection

[0042] When only white or light brown spherical parasitic pupae appear on the eggplant leaves in the rearing cage, start recording the time and wait for 2 days. After a large number of cotton aphid pupae appear, collect them. Pick the leaves containing the two parasitic pupae and rinse them with clean water using a pressurized water gun to obtain the two parasitic pupae.

[0043] Step 5: Remove impurities

[0044] The two parasitic wasp pupae that were washed off were rinsed and separated repeatedly to remove the heavier small clods of soil and sand. The two parasitic wasp pupae were then placed on a mesh screen to dry. After 1.5 days, the two parasitic wasp pupae were placed on a 40-mesh sieve to remove the fine impurities. Neither parasitic wasp pupae fell off.

[0045] Step 6: Separation of the two parasitic wasps

[0046] The pupae of the two parasitic wasps differ in size, with the pupae of *Aphidius cirrhosa* being larger than those of *Aphidius cirrhosa*. The pupae of the two types of wasps were separated by using sieves of different mesh sizes. A 40-mesh sieve was placed at the bottom to prevent the pupae from falling through. 25-mesh and 30-mesh sieves were placed in the middle layers to separate the smaller *Aphidius cirrhosa* and *Aphidius cirrhosa* pupae. A 20-mesh sieve was placed at the top to separate the larger *Aphidius cirrhosa* pupae. The pupae were sieved sequentially from top to bottom. First, both types of pupae were placed on the top sieve and sieved twice. The larger *Aphidius cirrhosa* pupae remained on the top sieve, while the smaller *Aphidius cirrhosa* and *Aphidius cirrhosa* pupae fell through the 25-mesh and 30-mesh sieves. Then, the pupae were sieved three times from high to low through the two types of sieves in the middle layer. The *Aphidius cirrhosa* pupae remained on the middle sieve, while the *Aphidius cirrhosa* pupae fell through the 40-mesh sieve at the bottom. In this way, the pupae of the two types of parasitic wasps were separated and collected separately for later use. Example 3

[0047] The present invention discloses a method for mixed rearing of two types of aphid parasitic wasps, comprising the following steps:

[0048] The first step is the propagation of host plants.

[0049] Fill small seedling pots with potting soil to a height of 6 cm, then sow eggplant seeds for seedling cultivation; when the eggplant seedlings are 6 cm tall, transplant them into medium-sized seedling trays, spray water regularly, and prepare them for use when the eggplant seedlings have grown to 8 leaves.

[0050] Step 2: Aphid Inoculation and Reproduction

[0051] Inoculate with aphids, specifically the peach aphid. Cut infested eggplant leaves into 2 cm squares, place them face down on new eggplant plants, 8 squares per plant. Place each plant in an insect rearing cage with a 120-mesh screen, maintaining an artificial climate of 28°C and 80% humidity. After the aphids have transferred to new eggplant plants, remove the square old leaves. Five days later, when the number of aphids on the new eggplant plants reaches 1000 per plant, inoculate with the tobacco aphid parasitic wasp.

[0052] Step 3: Obtaining and inoculating the two types of aphid-parasitic wasps

[0053] Pupae of two parasitic wasps, *Aphidius citrinum* and *Aphidius spp.*, were collected from eggplant vines. Larger, brightly colored individuals were selected and placed in rearing tubes with round holes in the caps, which were then sealed with 100-mesh mesh. The rearing tubes were placed in a constant temperature chamber at 26°C and 80% humidity, and the emergence of the pupae was observed daily. Adult *Aphidius citrinum* that emerged within 24 hours were placed in rearing cages at a density of 50 wasps per plant. Four days after inoculation with *Aphidius citrinum*, adult *Aphidius spp.* that emerged within 24 hours were inoculated again in the rearing cages at a density of 50 wasps per plant. After inoculation, the cages were placed in an artificial climate chamber at 28°C and 80% humidity.

[0054] Step 4: Parasitic wasp collection

[0055] When only white or light brown spherical parasitic pupae appear on the eggplant leaves in the rearing cage, start recording the time and wait for 3 days. After a large number of cotton aphid pupae appear, collect them. Pick the leaves with the two parasitic pupae and rinse them with clean water using a pressurized water gun to obtain the two parasitic pupae.

[0056] Step 5: Remove impurities

[0057] The two parasitic wasp pupae that were washed off were rinsed and separated repeatedly to remove the heavier small clods of soil and sand. The two parasitic wasp pupae were then placed on a mesh screen to dry. After 2 days, the two parasitic wasp pupae were placed on a 40-mesh sieve to remove the fine impurities. Neither parasitic wasp pupae fell off.

[0058] Step 6: Separation of the two parasitic wasps

[0059] The pupae of the two parasitic wasps differ in size, with the pupae of *Aphidius cirrhosa* being larger than those of *Aphidius cirrhosa*. The pupae of the two types of wasps were separated by using sieves of different mesh sizes. A 40-mesh sieve was placed at the bottom to prevent the pupae from falling through. 25-mesh and 30-mesh sieves were placed in the middle layers to separate the smaller *Aphidius cirrhosa* and *Aphidius cirrhosa* pupae. A 20-mesh sieve was placed at the top to separate the larger *Aphidius cirrhosa* pupae. The pupae were sieved sequentially from top to bottom. First, both types of pupae were placed on the top sieve and sieved twice. The larger *Aphidius cirrhosa* pupae remained on the top sieve, while the smaller *Aphidius cirrhosa* and *Aphidius cirrhosa* pupae fell through the 25-mesh and 30-mesh sieves. Then, the pupae were sieved three times from high to low through the two types of sieves in the middle layer. The *Aphidius cirrhosa* pupae remained on the middle sieve, while the *Aphidius cirrhosa* pupae fell through the 40-mesh sieve at the bottom. In this way, the pupae of the two types of parasitic wasps were separated and collected separately for later use.

[0060] The method for mixed rearing of two aphid parasitic wasps provided by the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, and improvements made on the basis of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for mixed rearing of two types of aphid parasitic wasps, characterized in that... Includes the following steps: The first step is the propagation of host plants. Fill small seedling pots with potting soil to a height of 4-6 cm, then sow eggplant seeds for seedling cultivation; when the eggplant seedlings are 4-6 cm tall, transplant them into medium-sized seedling trays, spray water regularly, and use them when the eggplant seedlings have grown to 6-8 leaves. Step 2: Aphid Inoculation and Reproduction Inoculate with aphids, specifically the peach aphid. Cut infested eggplant leaves into 2cm squares, place them face down on new eggplant plants, 6-8 squares per plant. Place each plant in an insect rearing cage with a 120-mesh screen, maintaining an artificial climate of 20-28℃ and 50-80% humidity. After the aphids have transferred to new eggplant plants, remove the square old leaves. 4-5 days later, when the number of aphids on the new eggplant plants reaches 800-1000 per plant, inoculate with the tobacco aphid parasitic wasp. Step 3: Obtaining and inoculating the two types of aphid-parasitic wasps Pupae of two parasitic wasps, *Aphidius citrinum* and *Aphidius spp.*, were collected from eggplant vines. Larger, brightly colored individuals were selected and placed in rearing tubes with round holes in the caps, which were then sealed with 100-mesh mesh. The rearing tubes were placed in a constant temperature chamber at 24-26℃ and 60-80% humidity, and the emergence of the pupae was observed daily. Adult *Aphidius citrinum* that emerged within 24 hours were placed in rearing cages at a density of 40-50 wasps per plant. Four days after inoculation with *Aphidius citrinum*, adult *Aphidius spp.* that emerged within 24 hours were inoculated again in the rearing cages at a density of 40-50 wasps per plant. After inoculation, the cages were placed in an artificial climate chamber at a temperature of 25-28℃ and a humidity of 50-80%. Step 4: Parasitic wasp collection When only white or light brown spherical parasitic pupae appear on the eggplant leaves in the rearing cage, start recording the time and wait for 2-3 days. After a large number of cotton aphid pupae appear, collect them. Pick the leaves with the two parasitic pupae and rinse them with clean water using a pressurized water gun to obtain the two parasitic pupae. Step 5: Remove impurities The two parasitic wasp pupae that were washed off were rinsed and separated repeatedly to remove the heavier small clods of soil and sand. The two parasitic wasp pupae were then placed on a mesh screen to dry. After 1-2 days, the two parasitic wasp pupae were placed on a 40-mesh sieve to remove the fine impurities. Neither parasitic wasp pupae should fall off. Step 6: Separation of the two parasitic wasps The pupae of the two parasitic wasps are different in size, with the pupae of the tobacco aphid wasp being larger than those of the cotton aphid wasp; the pupae of the two wasps were separated by placing sieves with different mesh sizes. The bottom layer uses a 40-mesh sieve to prevent the sifted pupae from falling through. The middle layer uses 25-mesh and 30-mesh sieves to separate the smaller *Aphidius cirrhosa* and *Aphidius spp.* pupae. The top layer uses a 20-mesh sieve to separate the larger *Aphidius cirrhosa* pupae. The pupae are sieved sequentially from top to bottom. First, the pupae of both types are placed on the top sieve and sieved twice. The larger *Aphidius cirrhosa* pupae remain on the top sieve, while the smaller *Aphidius cirrhosa* and *Aphidius spp.* pupae fall into the 25-mesh and 30-mesh sieves. Then, the pupae are sieved 2-3 times from high to low using the two types of sieves in the middle layer. The pupae remaining on the middle sieve are the *Aphidius cirrhosa* pupae, while the pupae that fall through to the bottom 40-mesh sieve are the *Aphidius spp.* In this way, the pupae of the two parasitic wasps are separated and collected separately for later use.

2. The method for mixed rearing of two aphid parasitic wasps according to claim 1, characterized in that: The small nutrient pot is a cylindrical container with a diameter of 8 cm and a height of 7.5 cm; the medium-sized seedling pot is a cylindrical container with a diameter of 12 cm and a height of 7.5 cm; the insect rearing cage is 50 cm long, 50 cm wide, and 50 cm high; the insect rearing tube has a diameter of 2.5 cm and a height of 8 cm; the diameter of the round hole in the lid of the insect rearing tube is 1.5 cm; and the pressure water gun has a rated flow rate of 2.4 m³ / h. 3 / h, power 0.75kW.