A functional release medium for predatory mites, its preparation method and usage method

Abstract

The present invention belongs to the field of biological control of agricultural pests, and specifically relates to a functional release medium for predatory mites, a preparation method thereof, and a usage method. The functional release medium for predatory mites includes entomogenous fungi, silica, diatomaceous earth, and fillers. Among them, the entomogenous fungi and diatomaceous earth can control various harmful mites and pests and have no negative impact on predatory mites. The use of this release medium can not only improve the control effect of predatory mites, but also have a certain control effect on other pests such as aphids and thrips, which can broaden the control target range of the original predatory mite products and achieve the integrated control of various harmful mites and pests. In addition, the usage method of this release medium is simple. The functional release medium for predatory mites can not only ensure the application dosage requirements of biocontrol microorganisms, but also reduce the number of field pesticide applications, while improving the control efficiency and effect, reducing the control cost.

Description

Technical Field

[0001] The present invention belongs to the field of biological control of agricultural pests, and particularly relates to a functional release medium for predatory mites, a preparation method thereof, and a usage method thereof. Background Art

[0002] For a long time, due to the abuse and misuse of pesticides, many small sap-sucking pests such as spider mites, thrips, whiteflies, aphids, etc. have become rampant, damaging crops, and often multiple pests occur mixedly, making chemical control increasingly difficult. In contrast, predatory mites, due to their small size, fast development, large reproduction amount, strong predation ability, and occupying a similar ecological niche with pests, have an effective control effect on pest mites and pests. Some predatory mite species with extremely strong predation ability, such as Phytoseiulus persimilis, can even achieve a rapid control effect similar to that of pesticides.

[0003] Phytoseiulus persimilis is a specialized predatory natural enemy of spider mites, with characteristics such as a large predation amount, strong fecundity, and rapid control. This mite has been introduced successively by many countries and commercially produced. Using Phytoseiulus persimilis to control spider mites on cotton, vegetables, fruit trees, and flowers has achieved remarkable control effects. However, this mite is stenophagous, feeding on spider mites and ineffective against pests such as thrips and aphids. In the case of mixed occurrence of multiple pest mites and pests, it needs to be used in combination with other natural enemies or agents to achieve an integrated control effect.

[0004] When applying predatory mites on a large scale, the inundative release method is often adopted. That is, commercially produced predatory mite products are mixed with media such as vermiculite and wheat bran, and then manually or using a special spreading machine to spread them on crops. Conventional release media are single-component materials such as vermiculite, wheat bran, or sawdust, which can only play the roles of filling, moisturizing, and uniform spreading, without other functions. Summary of the Invention

[0005] Based on the above technical background, the main purpose of the present invention is to provide a functional release medium for predatory mites, a preparation method thereof, and a usage method thereof, so as to overcome the deficiencies in the prior art.

[0006] To achieve the foregoing invention purpose, the technical solutions adopted by the present invention include:

[0007] In the first aspect of the present invention, there is provided a functional release medium for predatory mites, and the functional release medium for predatory mites includes entomogenous fungi, silicon dioxide, diatomaceous earth, and a filler;

[0008] The mass ratio of the entomogenous fungi, silicon dioxide, diatomaceous earth, and the filler is (1 - 5):(0.5 - 2):(20 - 40):(50 - 80).

[0009] Preferably, the mass ratio of the entomogenous fungi, silicon dioxide, diatomaceous earth, and the filler is 4:1:30:65.

[0010] Preferably, the entomogenous fungi are selected from one or two of the entomogenous fungi of Beauveria bassiana and Metarhizium anisopliae.

[0011] Preferably, the filler is selected from one or more of edible fungus residue, vermiculite and wheat bran.

[0012] More preferably, the filler is edible fungus residue.

[0013] More preferably, the mass ratio of the entomogenous fungus spore powder of Beauveria bassiana, the entomogenous fungus spore powder of Metarhizium anisopliae, silicon dioxide, diatomaceous earth and edible fungus residue is 2:2:1:30:65;

[0014] Or, the mass ratio of the Beauveria bassiana entomogenous fungus spore powder, silicon dioxide, diatomaceous earth and edible fungus residue is 4:1:30:65;

[0015] Or, the mass ratio of the green muscardine entomogenous fungus spore powder, silicon dioxide, diatomaceous earth and edible fungus residue is 4:1:30:65.

[0016] The second aspect of the present invention is to provide a method for preparing the functional release medium of predatory mites according to the first aspect of the present invention, the preparation method comprising the following steps:

[0017] Step 1, sterilizing and drying diatomaceous earth and filler;

[0018] Step 2: Mix the sterilized and dried diatomaceous earth and filler, entomogenous fungi and silicon dioxide to obtain a functional release medium for predatory mites.

[0019] Preferably, in step 1,

[0020] Sterilize the diatomaceous earth and filler at 100°C for 60 to 120 minutes;

[0021] Dry the sterilized diatomaceous earth and filler at 50-60°C for 45-90 minutes.

[0022] The third aspect of the present invention is to provide a method for using the predatory mite functional release medium according to the first aspect of the present invention, the method comprising:

[0023] Investigate the number of spider mites in the release field, the benefit-harm ratio of predatory mites to spider mites is 1:10-15, the application dosage of predatory mite functional release medium is 500g-1000g / mu, mix the predatory mites and the predatory mite functional release medium thoroughly according to this dosage, and spread them on the crop leaves. Choose a cloudy day, evening or early morning as the time for spreading, and avoid using any chemical pesticides 10 days before and after spreading.

[0024] Preferably, the predatory mite is Phytoseiidae chilensis.

[0025] Advantages of the present invention:

[0026] (1) The predatory mite functional release medium of the present invention comprises entomogenous fungi, silica, diatomaceous earth and filler. Among them, the entomogenous fungi and diatomaceous earth have control effects on various pest mites and pests, and have no negative impacts on the mortality rate, predation amount and yield of predatory mites. Titanium dioxide has an anti-ultraviolet function and plays a protective role on fungal spores and predatory mites. The use of this release medium not only has a filling effect, but also can improve the control effect of predatory mites. This release medium also has certain control effects on other pests such as aphids and thrips, can broaden the control object range of the original predatory mite products, realize the integrated control of various pest mites and pests, improve the control efficiency and reduce the control cost. It is found through experiments that compared with the use of a conventional release medium, the control effect of this release medium on spider mites is increased by 12.05%, and the control effect on aphids reaches 85.76% or more.

[0027] (2) Existing predatory mite products carrying bacteria only carry biocontrol microorganisms on the body surface of predatory mites, and the amount of bacteria carried cannot guarantee the application dosage requirements of biocontrol bacteria; although the separate application of biocontrol bacteria and predatory mites can guarantee the application dosage of biocontrol bacteria, it increases the number of pesticide application operations and raises the control cost; the predatory mite functional release medium of the present invention is mixed with predatory mites and then simultaneously applied to the field, and can be applied by manual or professional spreading machines. During the spreading process, the biocontrol microorganisms enter the release environment directly along with diatomaceous earth, etc. At the same time, the biocontrol microorganisms can also be carried and spread through the body surface of predatory mites to the gaps that the release medium cannot reach, further improving the control effect. The predatory mite functional release medium can not only guarantee the application dosage requirements of biocontrol microorganisms, but also reduce the number of pesticide applications in the field, reduce the control cost while improving the control efficiency. Description of the drawings

[0028] Figure 1 A line graph showing the change in the mortality rate of Tetranychus urticae over time after treatment with Metarhizium anisopliae in Experimental Example 1;

[0029] Figure 2 A line graph showing the change in the mortality rate of Phytoseiulus persimilis over time after treatment with Metarhizium anisopliae in Experimental Example 1;

[0030] Figure 3 Showing the average daily predation amount per individual Phytoseiulus persimilis after treatment with Metarhizium anisopliae in Experimental Example 1;

[0031] Figure 4 Showing the average daily egg production per individual Phytoseiulus persimilis after treatment with Metarhizium anisopliae in Experimental Example 1. Detailed implementation manners

[0032] The present invention will be described in detail below, and its features and advantages will become clearer and more definite with these descriptions.

[0033] The conventional release matrix of existing predatory mites is a single component such as vermiculite, wheat bran or sawdust, which can only play the roles of filling, moisturizing and uniform spreading, without other functions. The present invention screens entomogenous fungi that have good control effects on pests such as thrips, whiteflies and aphids, but have no negative impact on Phytoseiulus persimilis, and at the same time adds titanium dioxide, diatomaceous earth and fillers.

[0034] The first aspect of the present invention is to provide a functional release medium for predatory mites, and the functional release medium for predatory mites includes entomogenous fungi, silicon dioxide, diatomaceous earth and fillers.

[0035] The mass ratio of the entomogenous fungi, silicon dioxide, diatomaceous earth and fillers is (1-5):(0.5-2):(20-40):(50-80).

[0036] Preferably, the mass ratio of the entomogenous fungi, silicon dioxide, diatomaceous earth and fillers is 4:1:30:65.

[0037] According to a preferred embodiment of the present invention, the entomogenous fungi are selected from one or two of Beauveria bassiana entomogenous fungi and Metarhizium anisopliae entomogenous fungi, and preferably a mixture of Beauveria bassiana entomogenous fungi and Metarhizium anisopliae entomogenous fungi.

[0038] Beauveria bassiana and Metarhizium anisopliae have good control effects on pests such as spider mites, thrips, whiteflies and aphids, and have no adverse effects on the predation amount, fecundity and lifespan of Phytoseiulus persimilis.

[0039] The entomogenous fungi are preferably entomogenous fungal spore powders, and the mass ratio of Beauveria bassiana entomogenous fungal spore powder and Metarhizium anisopliae entomogenous fungal spore powder is preferably 1:1.

[0040] The fillers are selected from one or several of edible mushroom residues, vermiculite, wheat bran, and are preferably edible mushroom residues.

[0041] According to a preferred embodiment of the present invention, the mass ratio of Beauveria bassiana entomogenous fungal spore powder, Metarhizium anisopliae entomogenous fungal spore powder, silicon dioxide, diatomaceous earth and edible mushroom residues is 2:2:1:30:65.

[0042] Or, the mass ratio of Beauveria bassiana entomogenous fungal spore powder, silicon dioxide, diatomaceous earth and edible mushroom residues is 4:1:30:65.

[0043] Or, the mass ratio of Metarhizium anisopliae entomogenous fungal spore powder, silicon dioxide, diatomaceous earth and edible mushroom residues is 4:1:30:65.

[0044] The second aspect of the present invention is to provide a method for preparing the functional release medium of predatory mites according to the first aspect of the present invention, the preparation method comprising the following steps:

[0045] Step 1, sterilizing and drying diatomaceous earth and filler;

[0046] Step 2: Mix the sterilized and dried diatomaceous earth and filler, entomogenous fungi and silicon dioxide to obtain a functional release medium for predatory mites.

[0047] The above steps are described in detail below.

[0048] In step 1, the diatomaceous earth and the filler are sterilized at 100° C. for 60 to 120 min. Preferably, the diatomaceous earth and the filler are sterilized at 100° C. for 90 min.

[0049] The sterilized diatomaceous earth and filler are dried at 50-60° C. for 45-90 min. Preferably, the sterilized diatomaceous earth and filler are dried at 55° C. for 60 min, and the water content after drying is less than 5%.

[0050] In step 2, the sterilized and dried diatomaceous earth and filler are mixed with entomogenic fungi and silicon dioxide in a ratio of 30:65:4:1, and after mixing, the entomogenic fungi spore content in the functional release medium of predatory mites is greater than 3 billion spores / g.

[0051] The third aspect of the present invention is to provide a method for using the predatory mite functional release medium according to the first aspect of the present invention, the method comprising:

[0052] First, investigate the number of spider mites in the release field, prepare predatory mites according to the ratio of benefit-harm ratio of predatory mites to spider mites of 1:10-15, preferably 1:10, and the application dosage of predatory mite functional release medium is 500g-1000g / mu, preferably 1000g / mu. Mix the predatory mites and predatory mite functional release medium according to this usage, and spread them on the crop leaves by hand or professional spreading machine. The time of spreading should be cloudy, evening or early morning, avoid releasing and spreading on rainy days, strong winds and strong midday sunshine, and avoid using any chemical pesticides 10 days before and after spreading.

[0053] The predatory mite is preferably Phytoseiidae chilensis.

[0054] Example

[0055] The present invention is further described below by specific examples, which are limited to illustrating the present invention but not to limiting the scope of the present invention. The raw materials used in the present invention are all purchased.

[0056] Example 1

[0057] Sterilize diatomaceous earth and edible mushroom residues at 100 °C for 90 min, then dry them at 55 °C for 60 min. After drying, the water content is less than 5%, and they are used for subsequent use.

[0058] Mix Beauveria bassiana entomogenous fungal spore powder, Metarhizium anisopliae entomogenous fungal spore powder, silicon dioxide, diatomaceous earth, and edible mushroom residues according to a mass ratio of 2:2:1:30:65. After mixing, the spore content is greater than 3 billion spores / g, and the predatory mite functional release medium is obtained.

[0059] Example 2

[0060] Sterilize diatomaceous earth and edible mushroom residues at 100 °C for 90 min, then dry them at 55 °C for 60 min. After drying, the water content is less than 5%, and they are used for subsequent use.

[0061] Mix Metarhizium anisopliae entomogenous fungal spore powder, silicon dioxide, diatomaceous earth, and edible mushroom residues according to a mass ratio of 4:1:30:65. After mixing, the spore content is greater than 3 billion spores / g, and the predatory mite functional release medium is obtained.

[0062] Example 3

[0063] Sterilize diatomaceous earth and edible mushroom residues at 100 °C for 90 min, then dry them at 55 °C for 60 min. After drying, the water content is less than 5%, and they are used for subsequent use.

[0064] Mix Beauveria bassiana entomogenous fungal spore powder, silicon dioxide, diatomaceous earth, and edible mushroom residues according to a mass ratio of 4:1:30:65. After mixing, the spore content is greater than 3 billion spores / g, and the predatory mite functional release medium is obtained.

[0065] Example 4

[0066] Sterilize diatomaceous earth and edible mushroom residues at 100 °C for 60 min, then dry them at 55 °C for 60 min. After drying, the water content is less than 5%, and they are used for subsequent use.

[0067] Mix Beauveria bassiana entomogenous fungal spore powder, Metarhizium anisopliae entomogenous fungal spore powder, silicon dioxide, diatomaceous earth, and edible mushroom residues according to a mass ratio of 1:1:1:20:77. After mixing, the spore content is greater than 3 billion spores / g, and the predatory mite functional release medium is obtained.

[0068] Example 5

[0069] Sterilize diatomaceous earth and edible mushroom residues at 100 °C for 120 min, then dry them at 55 °C for 60 min. After drying, the water content is less than 5%, and they are used for subsequent use.

[0070] Mix Beauveria bassiana entomogenous fungal spore powder, Metarhizium anisopliae entomogenous fungal spore powder, silicon dioxide, diatomaceous earth, and edible mushroom residue in a mass ratio of 1:1:2:40:56. After mixing, the spore content is greater than 3 billion spores / g, and the predatory mite functional release medium is obtained.

[0071] Experimental Example

[0072] Experimental Example 1 Pathogenicity and Control Effect Test

[0073] 1. Test Materials

[0074] Metarhizium anisopliae, from the Institute of Plant Protection, Jilin Academy of Agricultural Sciences. Research shows that this strain has good control effects on various pests such as aphids.

[0075] Phytoseiulus persimilis, a population reared indoors at the Institute of Plant Protection, Jilin Academy of Agricultural Sciences.

[0076] The predatory mite functional release medium described in Example 2 was used for testing.

[0077] 2. Test Methods

[0078] 2.1 Pathogenicity of Metarhizium anisopliae to Tetranychus urticae

[0079] The spray method was used for inoculation. The Metarhizium anisopliae spore suspension of 10 8 spores / mL was respectively sprayed onto the adult female Tetranychus urticae with the same mite age. Each treatment had 10 replicates, with a total of 100 mites. The control group was sprayed with a solution containing 0.05% Tween-80. After spraying the bacteria, the petri dishes were placed in an incubator with a humidity of 70% ± 5%, a temperature of (25 ± 2) °C, and a photoperiod of 16L:8D. Observe and record the number of dead Tetranychus urticae every day, and pick out the dead mites. The dead mites were picked out and placed in a petri dish for moisturizing culture to observe whether Metarhizium anisopliae grew on the insect bodies, which was used as the basis for judging whether the mites were killed by Metarhizium anisopliae infection. The experiment was continuously observed for 10 days. The corrected mortality and median lethal time LT50 of Tetranychus urticae (i.e., the time required for Metarhizium anisopliae to kill half of the mites) were calculated using the data obtained according to formula (1).

[0080] Corrected mortality (%) = (treatment mortality - control mortality) / (1 - control mortality) × 100% Formula (1);

[0081] 2.2 Pathogenicity of Metarhizium anisopliae to Phytoseiulus persimilis

[0082] Use a small brush to pick out adult Phytoseiulus persimilis with the same size, healthy and lively, and put them into 10 8After being soaked in the Metarhizium anisopliae suspension at [[X]] spores / mL for 5 seconds, take them out, suck off the excess suspension around the mites, and place them in a small chamber composed of two transparent acrylic plates. Put 1 predatory mite Phytoseiulus persimilis in each chamber. The predatory mites in the control group were treated with a solution containing 0.05% Tween-80. Each treatment had 4 replicates, with 15 Phytoseiulus persimilis in each replicate. Observe and record the death situation of each treatment at a fixed time every day and supplement the food. Observe continuously for 10 days, remove the dead mites, and culture them under humid conditions. According to the growth of hyphae on the dead mite bodies, calculate the mortality rate and the rate of mummified mites.

[0083] 2.3 Effects of Metarhizium anisopliae on the predation of Phytoseiulus persimilis

[0084] Use a small brush to pick out female adult Phytoseiulus persimilis with consistent size, healthy and lively, and put them into 8 the Metarhizium anisopliae suspension at [[X]] spores / mL and soak for 5 seconds, then take them out, suck off the excess suspension around the mites, and place them on a leaf disc with 15 adult spider mites. The control group was treated with a solution containing 0.05% Tween-80. Supplement the food every day and count the number of prey captured by the predatory mites in different treatments. Continuously investigate for 5 days, and measure 15 female adult mites for each treatment.

[0085] 2.4 Effects of Metarhizium anisopliae on the fecundity of Phytoseiulus persimilis

[0086] Use a small brush to pick out female adult Phytoseiulus persimilis with consistent size, healthy and lively, and put them into 8 the Metarhizium anisopliae suspension at [[X]] spores / mL and soak for 5 seconds, then take them out, suck off the excess suspension around the mites, and place them in a small chamber composed of two transparent acrylic plates. Put 1 predatory mite Phytoseiulus persimilis in each chamber. The predatory mites in the control group were treated with a solution containing 0.05% Tween-80. Observe and record the fecundity of each treatment at a fixed time every day and supplement the food. Observe continuously for 5 days, and measure 15 female adult mites for each treatment.

[0087] 2.5 Control effect of the functional release medium for predatory mites

[0088] Inoculate spider mites and aphids on greenhouse eggplants. After one week, conduct the experimental treatment (the number of spider mites and aphids is 57.4 heads / plant and 18.8 heads / plant on average). The experiment set up 4 treatment groups: predatory mites, predatory mites (the beneficial-to-harm ratio of predatory mites to spider mites is 1:10) + medium (the functional release medium for predatory mites prepared in Example 2) at 500 g / mu, predatory mites (the beneficial-to-harm ratio of predatory mites to spider mites is 1:10) + medium (the functional release medium for predatory mites prepared in Example 2) at 1000 g / mu, and the control group. The control group did not take any control measures, and the beneficial-to-harm ratio of Phytoseiulus persimilis to spider mites is 1:10. Investigate the population numbers of spider mites and aphids on the 10th day and 20th day after release respectively, and calculate the control effect.

[0089] 3. Experimental results

[0090] 2.1 Pathogenicity of Metarhizium anisopliae against Tetranychus urticae

[0091] The test results are as Figure 1 shown. It can be seen from Figure 1 that after spraying Metarhizium anisopliae, the mortality rate of Tetranychus urticae increased significantly compared with the control, and increased gradually with the treatment time. After 10 days of treatment, the mortality rate of Tetranychus urticae sprayed with Metarhizium anisopliae reached 85%, and the corrected mortality rate was 80.13%. The median lethal time of Metarhizium anisopliae against Tetranychus urticae was 4.158 days.

[0092] 2.2 Pathogenicity of Metarhizium anisopliae against Phytoseiulus persimilis

[0093] The test results of the pathogenicity of Metarhizium anisopliae against Phytoseiulus persimilis are as Figure 2 shown. It can be seen from Figure 2 that with the extension of the investigation time, the mortality rate of Phytoseiulus persimilis showed a gradually increasing trend, but there was no significant difference in the mortality rate of Phytoseiulus persimilis treated with Metarhizium anisopliae compared with the control at the same investigation time.

[0094] 2.3 Effect of Metarhizium anisopliae on the predation of Phytoseiulus persimilis

[0095] The predation amount of Phytoseiulus persimilis on Tetranychus urticae after different treatments is as Figure 3 shown. After being treated with Metarhizium anisopliae, the total predation amount of Phytoseiulus persimilis in 5 days was 18.57, and the average daily predation amount per individual was 4.08; the total predation amount of Phytoseiulus persimilis in the control treatment in 5 days was 22, and the average daily predation amount per individual was 4.63. There was no significant difference between the two (total predation amount t = 0.869, F = 0.394; average daily predation amount per individual t = 0.184, F = 0.258).

[0096] 2.4 Effect of Metarhizium anisopliae on the reproduction of Phytoseiulus persimilis

[0097] The egg production amount of Phytoseiulus persimilis after different treatments is as Figure 4 shown. After being treated with Metarhizium anisopliae, the total egg production amount of Phytoseiulus persimilis in 5 days was 18.49, and the average daily egg production amount per individual was 3.62; the total egg production amount of Phytoseiulus persimilis in the control treatment in 5 days was 17.93, and the average daily egg production amount per individual was 3.49. There was no significant difference between the two (total egg production amount t = 0.679, F = 0.496; average daily egg production amount per individual t = 0.1708, F = 0.103).

[0098] 2.5 Control effect of functional release medium of predatory mites

[0099] The numbers of spider mites and aphids investigated at different times are shown in Table 1.

[0100] Table 1

[0101]

[0102] As can be seen from Table 1, after treating spider mites and aphids with the predatory mite functional release medium of the present invention, the numbers of spider mites and aphids are significantly reduced. After treatment with 500 g / mu of predatory mite + medium, the control effect after 10 days is increased by 5.55% compared with the treatment with only predatory mites. After treatment with 1000 g / mu of predatory mite + medium, the control effect after 10 days is increased by 12.05% compared with the treatment with only predatory mites. At the same time, it also has a good control effect on aphids, and the control effect reaches more than 75%.

[0103] In summary, the Metarhizium anisopliae added in the predatory mite functional release medium of the present invention has strong pathogenicity to both aphids and spider mites, but has no significant effect on the mortality, predation amount and yield of Phytoseiulus persimilis. It shows that applying the predatory mite functional release medium of the present invention can not only improve the control effect of predatory mite products on spider mites, but also has a good control effect on aphids. This predatory mite functional release medium broadens the control target range of the original predatory mite products, can realize the integrated control of various harmful mites and pests, improve the control efficiency and reduce the control cost.

[0104] The present invention has been described in detail above in combination with specific embodiments and exemplary examples, but these descriptions should not be construed as limiting the present invention. Those skilled in the art understand that without departing from the spirit and scope of the present invention, various equivalent substitutions, modifications or improvements can be made to the technical solutions and their implementation manners of the present invention, and these all fall within the scope of the present invention. The protection scope of the present invention is subject to the appended claims.

Claims

1. A functional release medium for predatory mites, characterized in that, The functional release medium for predatory mites comprises entomogenous fungi, silicon dioxide, diatomaceous earth and fillers; The entomogenous fungi are selected from one or two of Beauveria bassiana and Metarhizium anisopliae; The filler is edible fungus residue; The mass ratio of the Beauveria bassiana entomogenous fungus spore powder, Metarhizium anisopliae entomogenous fungus spore powder, silicon dioxide, diatomaceous earth and edible fungus residue is 2:2:1:30:

65.

2. The predatory mite functional release medium according to claim 1, characterized in that: The mass ratio of the beauveria bassiana entomogenous fungus spore powder, silicon dioxide, diatomaceous earth and edible fungus residue is 4:1:30:65; Or, the mass ratio of the green muscardine entomogenous fungus spore powder, silicon dioxide, diatomaceous earth and edible fungus residue is 4:1:30:

65.

3. A method for preparing the predatory mite functional release medium according to claim 1 or 2, characterized in that, The preparation method comprises the following steps: Step 1, sterilizing and drying diatomaceous earth and filler; Step 2: Mix the sterilized and dried diatomaceous earth and filler, entomogenous fungi and silicon dioxide to obtain a functional release medium for predatory mites.

4. The preparation method according to claim 3, characterized in that, In step 1, Sterilize the diatomaceous earth and filler at 100°C for 60 to 120 minutes; Dry the sterilized diatomaceous earth and filler at 50-60°C for 45-90 minutes.

5. A method for using the predatory mite functional release medium according to claim 1 or 2, characterized in that, The method of use includes: Investigate the number of spider mites in the released fields. The benefit-harm ratio of predatory mites to spider mites is 1:10-15. The application dosage of the functional release medium for predatory mites is 500g-1000g / mu. According to this dosage, fully mix the predatory mites and the functional release medium for predatory mites and spread them on the leaves of crops. Choose a cloudy day, evening or early morning as the time for spreading. Avoid using any chemical pesticides 10 days before and after spreading.

6. The method of use according to claim 5, characterized in that: The predatory mite is Phytoseiidae chilensis.

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