Biological pesticide for preventing and treating tetranychus cinnabarinus of cassava

Abstract

The invention belongs to the technical field of biopesticides, and particularly relates to a biopesticide for preventing and treating cassava tetranychus cinnabarinus. The invention relates to a biopesticide. The biopesticide is prepared by compounding cordyceps javanica, etoxazole nitrile, cnidium lactone or rotenone, wherein the cordyceps javanica is a cordyceps javanica Ij01 parent drug with 10 billion spores per gram. When the biopesticide composition is used for preventing and treating the tetranychus cinnabarinus of cassava, the prevention and treatment effect can be improved, the dosage of the pesticide is reduced, the environmental pressure and pesticide residues are reduced, meanwhile, accumulation and development of pesticide resistance of pests can be delayed, and the biopesticide composition can be used for developing a biopesticide preparation for preventing and treating the tetranychus cinnabarinus of cassava.

Description

Technical Field

[0001] The invention belongs to the technical field of biological pesticides, and in particular relates to a biological pesticide for preventing and controlling cassava spider mites. Background Art

[0002] Cassava is an important food crop and energy crop in the world. It has great development potential due to its high starch content, high yield, resistance to barrenness and easy management. It is one of the world's three major tuber crops, the third largest tropical food crop, and the sixth largest food crop in the world. It is known as the "king of starch".

[0003] Tetranychus cinnabarinus, commonly known as red spider, is a common mite in cassava cultivation in my country, with more than 1,100 host plants. It can live on the back of cassava leaves and suck juice, causing the leaves to dry and fall off, or even plant death, seriously affecting cassava yields and is one of the main factors restricting the development of the cassava industry.

[0004] At present, the control of spider mites mainly relies on chemical insecticides (mites), but due to the small size, rapid reproduction, strong adaptability, wide host range, and easy resistance of spider mites, the chemical control effect is not ideal. In addition, the long-term and large-dose use of chemical agents will increase environmental pressure and there will be problems of excessive pesticide residues. Therefore, it is particularly important to seek non-chemical control agents.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] The purpose of the present invention is to provide a biological pesticide for controlling cassava spider mites, so as to solve the problems existing in controlling spider mites by chemical insecticides (mites).

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A biological pesticide is prepared by compounding Cordyceps javanica and ethidium cypermethrin, osthole or rotenone; wherein the Cordyceps javanica is Cordyceps javanica Ij01 mother drug with 100 billion spores / gram.

[0009] Preferably, the mass ratio of the Cordyceps javanica to ethidium bromide is 1-16:4-1.

[0010] Preferably, the mass ratio of the Cordyceps javanica to osthole is 1-19:9-1.

[0011] Preferably, the mass ratio of the Cordyceps javanica to rotenone is 1-6:12-1.

[0012] The invention also provides application of the biological pesticide in preventing and controlling cassava spider mites.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] The invention compounds Javanese Cordyceps Ij01 with ethoxachlor, osthole or rotenone to form a biological pesticide, wherein within a mass ratio of 1-16:4-1, the compound combination of Javanese Cordyceps Ij01 and ethoxachlor shows a synergistic effect on cassava spider mites; within a mass ratio of 1-19:9-1, the compound combination of Javanese Cordyceps Ij01 and osthole shows a synergistic effect on cassava spider mites; within a mass ratio of 1-6:12-1, the compound combination of Javanese Cordyceps Ij01 and rotenone shows a synergistic effect on cassava spider mites. It can be seen that when the biological pesticide composition of the invention is used to control cassava spider mites, the control effect can be improved, the amount of the agent used can be reduced, the environmental pressure and the problem of pesticide residues can be alleviated, and at the same time, the accumulation and development of pest resistance can be delayed, and the biological pesticide preparation for developing control of cassava spider mites can be used. DETAILED DESCRIPTION

[0015] The following is a clear and complete description of the technical solution of the patent of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by technicians in this field without creative work are within the scope of protection of the present invention.

[0016] 1. Materials and Methods

[0017] 1.1 Test reagents

[0018] 98% ethazolin technical (Shenyang Kechuang Chemicals Co., Ltd.), 10% osthole stock solution (Inner Mongolia Qingyuanbao Biotechnology Co., Ltd.), 95% rotenone technical (Hebei Tianshun Bioengineering Co., Ltd.), 100 billion spores / g Cordyceps javanica Ij01 stock (Guangdong Dafeng Plant Protection Technology Co., Ltd.)

[0019] The mother liquid of Cnidium monnieri is diluted with a 0.05% Triton X-100 aqueous solution to form a single-dose mother liquid; the mother medicine of Cordyceps javanica Ij01 is diluted with a 0.05% Triton X-100 aqueous solution to form a suspension as a single-dose mother liquid; the original medicine of ethidium cypermethrin and the original medicine of rotenone are dissolved with dimethyl sulfoxide, and then diluted with a 0.05% Triton X-100 aqueous solution to form a single-dose mother liquid; multiple ratios are set, and each single dose and each group of mixed medicines are diluted with a 0.05% Triton X-100 aqueous solution to form 5 mass concentration gradients, and the above medicines are prepared and used immediately.

[0020] 2. Test pests

[0021] Cinnabarinus spider mites were collected from the leaves of cassava plants and were continuously raised on fresh and clean cassava leaves in the laboratory for 5 generations. Female adult mites of uniform size were selected as test pests.

[0022] 3. Test method (refer to "Guidelines for Indoor Bioassay Tests of Pesticides - Insecticides Part 12: Spider Mite Slide Dipping Method")

[0023] Cut the double-sided tape into 2cm long pieces and stick them horizontally on one end of the glass slide. Stick the back of the test insect on the double-sided tape. Stick two rows on each glass slide, 15 insects in each row, for a total of 30 insects. Place the stuck glass slide in a white porcelain plate, spread a layer of moist gauze on the bottom of the white porcelain plate, cover the white porcelain plate with a glass plate, and place it in an artificial incubator at (25±1)℃, relative humidity (60±5)%, and a photoperiod of 16L / 8D. After 2h, examine with an Olympus stereo microscope, remove dead and injured individuals, and replenish 30 insects on each glass slide. Immerse the glass slide in the drug solution and shake it gently for 5s before taking it out. Use filter paper to quickly absorb the residual drug solution around the test insect. After the drug solution is dried, place it in a white porcelain plate, cover it with a glass plate, and transfer it to the artificial incubator again. Each treatment was repeated 4 times, and the treatment with 0.05% Triton X-100 aqueous solution was set as a blank control. After 24 hours, the mortality of the test insects was checked with a stereoscope. The spider mites were gently touched with a soft brush. The spider mites whose feet did not move were considered dead. The adjusted mortality rate of each treatment was calculated.

[0024]

[0025] In the above formula: P--mortality rate, unit is %; K--number of dead insects; N--total number of insects treated.

[0026]

[0027] In the above formula: P 1 --Adjusted mortality rate, in %; P t --Treatment mortality rate, in %; P 0 --Blank control mortality rate, in %.

[0028] 4. Data Analysis

[0029] Regression analysis was performed on the logarithmic values ​​of drug concentration and the probability of efficacy to calculate the EC of each drug. 50 The synergistic effect of mixed agents was evaluated based on the synergistic coefficient SR, and the results are shown in Table 1-3.

[0030] Table 1 The combined toxicity results of Cordyceps javanica Ij01 and ethazolin on Tetranychus cinnabarinus

[0031]

[0032] As shown in Table 1, after Cordyceps javanica Ij01 and ethidium bromide are compounded, the synergistic coefficient SR against Tetranychus cinnabarinus is greater than 1.5 within the mass ratio range of 1-16:4-1, showing a synergistic effect.

[0033] Table 2 The combined toxicity results of Cordyceps javanica Ij01 and osthole against Tetranychus cinnabarinus

[0034]

[0035] As shown in Table 2, after the combination of Cordyceps javanica Ij01 and osthole, the synergistic coefficient SR on Tetranychus cinnabarinus was greater than 1.5 within the mass ratio range of 1-19:9-1, showing a synergistic effect.

[0036] Table 3 The toxicity results of the combined action of Cordyceps javanica Ij01 and rotenone on Tetranychus cinnabarinus

[0037]

[0038] As shown in Table 3, after Cordyceps javanica Ij01 and rotenone were compounded, the synergistic coefficient SR against Tetranychus cinnabarinus was greater than 1.5 within the mass ratio range of 1-6:12-1, showing a synergistic effect.

[0039] The invention compounded Javanese Cordyceps Ij01 and ethoxachlor, osthole or rotenone to form a biological pesticide, wherein within a mass ratio of 1-16:4-1, the compound combination of Javanese Cordyceps Ij01 and ethoxachlor shows a synergistic effect on cassava spider mites; within a mass ratio of 1-19:9-1, the compound combination of Javanese Cordyceps Ij01 and osthole shows a synergistic effect on cassava spider mites; within a mass ratio of 1-6:12-1, the compound combination of Javanese Cordyceps Ij01 and rotenone shows a synergistic effect on cassava spider mites. It can be seen that when the biological pesticide composition of the invention is used to control cassava spider mites, the control effect can be improved, the amount of the agent used can be reduced, the environmental pressure and the problem of pesticide residues can be solved, and at the same time, the accumulation and development of pest resistance can be delayed, and the biological pesticide preparation for developing control of cassava spider mites can be used.

[0040] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A biological pesticide, characterized in that: The biological pesticide is prepared by compounding Cordyceps javanica, ethidium bromide, osthole or rotenone; wherein the Cordyceps javanica is Cordyceps javanica Ij01 mother drug with 100 billion spores / gram.

2. The biopesticide according to claim 1, characterized in that: The mass ratio of the Cordyceps javanica to ethidium bromide is 1-16:4-1.

3. The biopesticide according to claim 1, characterized in that: The mass ratio of the Cordyceps javanica to osthole is 1-19:9-1.

4. The biopesticide according to claim 1, characterized in that: The mass ratio of the Cordyceps javanica to rotenone is 1-6:12-1.

5. Use of the biological pesticide according to claim 1 in controlling cassava spider mites.

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